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The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Immune competence is a key factor in the health and resilience of dairy ruminants. The aim of this study was to study IgG concentration in serum shortly after birth and in colostrum of lactating animals as proxy of passive immune transfer and colostrum quality, respectively, and thus provide new health and resilience indicators for selection. Data from 424 female kids and 203 primiparous goats, reared on an INRAE experimental farm, were analyzed. The IgG concentration was measured in kid serum and goat colostrum, respectively, using the radial immunodiffusion technique. Linear models were used to identify factors of variation in serum and colostrum IgG concentration, and health events were monitored for 5 wk after birth to measure the effect of passive immune transfer on kids' health. We found a significant effect of serum IgG level on hindquarters cleanliness score (as a proxy of digestive troubles) and nasal and ocular discharge. As expected, the absorption of IgG in the days following birth is essential to ensure the passive transfer of immunity from the mother to the youngster, and provide immune protection. Genetic parameters were estimated for serum IgG concentration in kids and for colostrum characteristics in primiparous goats. Heritability of serum IgG in kids was not significantly different from zero. This low value, with large SE, may be due to the limited sample size and large environmental variability likely not accounted for. Especially, we could not adjust for the amount of IgG that was ingested by the kid, which can have a significant effect on serum IgG and possibly on heritability estimates. Heritability of colostrum traits were moderate, with estimates of 0.25 (±0.16), 0.35 (±0.16), and 0.25 (±0.16) for IgG concentration, IgG mass, and colostrum volume, respectively. Genetic correlations with milk production showed high standard errors due to small numbers. However, estimates suggest a negative genetic association between production and IgG concentration in colostrum (genetic correlation = −0.44 ± 0.33), probably linked to a positive association with total colostrum volume. The significant heritabilities that were estimated for the first time demonstrate the existence of genetic control of colostrum quality in goats, and open up opportunities for selection in this species. [ABSTRACT FROM AUTHOR]

Age at first calving (AFC) is a measure of sexual maturity associated with the start of productive life of dairy animals. Additionally, a lower AFC reduces the generation interval and early culling of females. However, AFC has low heritability, making it a trait highly influenced by environmental factors. In this scenario, one way to improve the reproductive performance of buffalo cows is to select robust animals according to estimated breeding value (EBV) using models that include genotype–environment interaction (GEI) with the application of reaction norm models (RNMs). This can be achieved by understanding the genomic basis related to GEI of AFC. Thus, in this study, we aimed to predict EBV considering GEI via the RNM and identify candidate genes related to this component in dairy buffaloes through genome‐wide association studies (GWAS). We used 1795 AFC records from three Murrah buffalo herds and formed environmental gradients (EGs) from contemporary group solutions obtained from genetic analysis of 270‐day cumulative milk yield. Heritability estimates ranged from 0.15 to 0.39 along the EG. GWAS of the RNM slope parameter identified important genomic regions. The genomic window that explained the highest percentage of genetic variance of the slope (0.67%) was located on BBU1. After functional analysis, five candidate genes were detected, involved in two biological processes. The results suggested the existence of a GEI for AFC in Murrah buffaloes, with reclassification of animals when different environmental conditions were considered. The inclusion of genomic information increased the accuracy of breeding values for the intercept and slope of the reaction norm. GWAS analysis suggested that important genes associated with the AFC reaction norm slope were possibly also involved in biological processes related to lipid metabolism and immunity. [ABSTRACT FROM AUTHOR]

In tropical beef cattle production systems, animals are commonly raised on pastures, exposing them to potential stressors. The end of gestation typically overlaps with a dry period characterized by limited food availability. Late gestation is pivotal for fetal development, making it an ideal scenario for inter‐ and transgenerational effects of the maternal gestational environment. Intergenerational effects occur due to exposure during gestation, impacting the development of the embryo and its future germline. Transgenerational effects, however, extend beyond direct exposure to the subsequent generations. The objective of the present study was to verify these effects on the post‐natal performance of zebu beef cattle. We extended the use of a reaction norm model to identify genetic variation in the animals' responses to transgenerational effects. The inter‐ and transgenerational effects were predominantly positive (−0.09% to 19.74%) for growth and reproductive traits, indicating improved animal performance on the phenotypic scale in more favourable maternal gestational environments. Additionally, these effects were more pronounced in the reproductive performance of females. On average, the ratio of direct additive genetic variances of the slope and intercept of the reaction norm ranged from 1.23% to 3.60% for direct and from 10.17% to 11.42% for maternal effects. Despite its relatively modest magnitude, this variation proved sufficient to prompt modifications in parameter estimates. The average percentage variation of direct heritability estimates ranged from 19.3% for scrotal circumference to 33.2% for yearling weight across the environmental descriptors evaluated. Genetic correlations between distant environments for the studied traits were generally high for direct effects and far from unity for maternal effects. Changes in EBV rankings of sires across different gestational environments were also observed. Due to the multifaceted nature of inter‐ and transgenerational effects of the maternal gestational environment on various traits of beef cattle raised under tropical pasture conditions, they should not be overlooked by producers and breeders. There were differences in the specific response of beef cattle to variations in the quality of the maternal gestational environment, which can be partially explained by transgenerational epigenetic inheritance. Adopting a reaction norm model to capture a portion of the additive variance induced by inter‐ or transgenerational effects could be an alternative for future research and animal genetic evaluations. [ABSTRACT FROM AUTHOR]

Temperament (docility) is a key breeding goal in the cattle industry due to its direct relationship with animal welfare, cattle handler's safety and animal productivity. Over the past six decades, numerous studies have reported heritability estimates for temperament‐related traits in cattle populations ranging from low to high values. Therefore, the primary objective of this study was to perform a comprehensive systematic review with meta‐analysis to obtain weighted estimates of heritability for temperament‐related traits in worldwide cattle populations. After data editing and quality control, 106 studies were included in the systematic review, of which 29.2% and 70.8% reported estimates of heritability for temperament‐related traits in dairy and beef cattle populations, respectively. Meta‐analyses were performed for 95 heritability estimates using a random model approach. The weighted heritability estimates were as follow: (a) flight score at weaning = 0.23 (95% CI: 0.15–0.32); (b) flight speed at weaning = 0.30 (95% CI: 0.26–0.33); (c) joint analysis of flight speed and flight score at weaning = 0.27 (95% CI: 0.22–0.31); (d) flight speed at yearling = 0.26 (95% CI: 0.21–0.30); (e) joint analysis of flight speed at weaning and yearling = 0.27 (95% CI: 0.24–0.30); (f) movement score = 0.12 (95% CI: 0.08–0.15); (g) crush score at weaning = 0.21 (95% CI: 0.17–0.25); (h) pen score at weaning = 0.27 (95% CI: 0.19–0.34); (i) pen score at yearling = 0.20 (95% CI: 0.17–0.23); (j) joint analysis of pen score at weaning and yearling = 0.22 (95% CI: 0.18–0.26); (k) cow's aggressiveness at calving = 0.10 (95% CI: 0.01–0.19); (l) general temperament = 0.13 (95% CI: 0.06–0.19); (m) milking temperament = 0.16 (95% CI: 0.11–0.21); and (n) joint analysis of general and milking temperament = 0.14 (95% CI: 0.11–0.18). The heterogeneity index ranged from 0% to 77%, and the Q‐test was significant (p < 0.05) for four single‐trait meta‐analyses. In conclusion, temperament is moderately heritable in beef cattle populations, and flight speed at weaning had the highest weighted heritability estimate. Moreover, between‐study heterogeneity was low or moderate in beef cattle traits, suggesting reasonable standardization across studies. On the other hand, low‐weighted heritability and high between‐study heterogeneity were estimated for temperament‐related traits in dairy cattle, suggesting that more studies are needed to better understand the genetic inheritance of temperament in dairy cattle populations. [ABSTRACT FROM AUTHOR]

Karan Fries (KF) cattle is India's newly developed dairy breed with high production potential. The present study was undertaken to evaluate 17 linear-type traits, behavioural and functional traits for estimating the genetic parameters and to find their association with production performance in KF cattle using a multi-trait Bayesian animal model. Among linear-type traits, stature, chest girth, body length and body depth had a high positive genetic and phenotypic correlation (ranging from 0.30 ± 0.01 to 0.74 ± 0.03) with production traits (total milk yield and 305 days milk yield). The majority of the linear-type traits, milking temperament and milking speed were moderately heritable (ranging from 0.25 ± 0.04 to 0.40 ± 0.03), while days open had low heritability (0.20 ± 0.25). This study showed the importance of reliable assessment of genetic parameters and incorporation of a few linear-type traits having high heritability and genetic correlation with production traits, can be utilized for future selection and breeding programmes in KF cattle. [ABSTRACT FROM AUTHOR]

Simple Summary: Reproductive performance is a critical factor for the economic success and long-term viability of dairy herds. Intense selection for milk production has resulted in a decline in fertility traits in Holstein cows, leading to negative consequences for the industry. To combat this, incorporating fertility traits into the genetic evaluation is a potential solution. However, fertility data are often incomplete due to a variety of reasons; in this study, which has a limited dataset, it is essential to address this issue. The study utilized three methods to handle censorship: a linear model, a penalty method, and a threshold linear model with a penalty. The findings revealed that the penalized threshold model showed a slightly higher heritability compared to linear models. Moreover, both the penalty method and the threshold method exhibited comparable predictive abilities and substantial overlap in common animals, suggesting that both methods can be employed to impute days open censored data in this population. Reproductive efficiency is a key element of profitability in dairy herds. However, the genetic evaluation of fertility traits is often challenged by the presence of high censorship rates due to various reasons. An easy approach to address this challenge is to remove the censored data from the dataset. However, removing data might bias the genetic evaluation. Therefore, addressing this issue is crucial, particularly for small populations and populations with limited size. This study uses a Moroccan Holstein dataset to compare two Gaussian linear models and a threshold linear model to handle censored records of days open (DO). Data contained 8646 records of days open across the first three parities of 6337 Holstein cows. The pedigree file comprised 11,555 animals and 14.51% of the dataset was censored. The genetic parameters and breeding values of DO were computed using three different methods: a linear model where all censored records were omitted (LM), a penalty method in which a constant equal to one estrus cycle in cattle was added to the maximum value of DO in each contemporary group to impute the censored records (PLM), and a bivariate threshold model with a penalty (PTM). The heritability estimates were equal to 0.021 ± 0.01 (PLM), 0.029 ± 0.01 (LM), and 0.033 ± 0.01 (PTM). The penalty method and the threshold linear model with a penalty showed better prediction accuracy calculated using the LR method (0.21, and 0.20, respectively). PLM and PTM had a high Spearman correlation (0.99) between the estimated breeding values of the validation dataset, which explains the high percentage of common animals in the top 20% of selected animals. The lack of changes in the ranking of animals between PLM and PTM suggests that both methods can be used to address censored data in this population. [ABSTRACT FROM AUTHOR]

ABSTRACT The aim was to estimate the heritabilities for accumulated weight gain between 60 and 90 days (WG1), 90 and 120 days (WG2) and 120 and 150 days of age (WG3), pre‐slaughter body weight (PRE), meat‐to‐shell ratio (MS), carcass yield (CY) and age at first oviposition (AFO) in a population of snails Cornu aspersum maximum. Single (for heritabilities) and bi‐trait (for genetic correlations) analyses were performed using Bayesian inference. The animal model included the random effect of animal and systematic effects of contemporary groups and covariates. The heritability estimates for WG1, WG2 and WG3 were 0.59, 0.60 and 0.32, respectively. Heritabilities for PRE, MS, CY and AFO ranged from 0.22 to 0.51. Environmental factors mostly influenced PRE among the studied traits. However, for carcass traits and age at first oviposition, the 95% HPD intervals of estimates were large. Only the genetic correlations between weight gains reached chain convergence. The correlation between WG1 and WG2 was 0.74, between WG2 and WG3 was 0.57, and between WG1 and WG3 was 0.22 (not statistically significant). In this sense, WG1 appears to be the optimal period for evaluating the body performance of snails. Genetic improvement in WG2 may be obtained by direct selection for WG1 in this population of Cornu aspersum maximum. [ABSTRACT FROM AUTHOR]

Background: Originating from the cold and arid regions of northwestern China, Kazakh sheep are dual-purpose breeds optimized for both meat and fat production. In contrast, Texel sheep are internationally recognized for their high-quality meat and exceptional flavor. Previous studies have indicated that the hybrids of Texel and Kazakh sheep exhibit significant quality advantages. Additionally, body weight is a crucial indicator of sheep production performance, directly correlating with meat yield and economic returns. Objective: This study aims to identify genetic variations and related genes associated with the body weight traits of hybrid lambs, thereby revealing their genetic mechanisms. Methods: This study genotyped hybrid lambs using a 50K chip and performed rigorous quality control on both genotypic and phenotypic data. The traits examined include body weight traits of lambs at various stages such as birth, pre-weaning, and post-weaning. Various genome-wide association study (GWAS) models were utilized to analyze the association between lamb body weight traits and genetic markers. The study then employed an Ensemble-like GWAS (E-GWAS) strategy to integrate these models, achieving a stable list of SNPs, rather than a mere aggregation. Multiple annotation databases were consulted to further investigate the mechanisms by which genetic markers affect body weight traits. All study results were validated through an extensive literature review. Results: Analyses with multiple statistical models revealed that 48 SNPs were significantly associated with body weight traits. The annotation process identified 24 related genes (including 4 unknown genes) and 9 quantitative trait loci (QTLs). Additionally, 6 Gene Ontology (GO) terms and 22 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were determined. Conclusions: This study identified key genes and pathways in the body weight traits of hybrids between Texel and Kazakh sheep, enhancing our understanding of their genetic mechanisms. [ABSTRACT FROM AUTHOR]

Plant breeding of Coffea canephora is based on the characterization and use of the natural genetic variability of the species. Thus, the objective of this study was to quantify the genetic diversity and gains from selection of the fruit and bean physical traits of the C. canephora plant, seeking to understand the relations among the yield components and identify genotypes with superior traits. For this purpose, 42 genotypes were evaluated over two crop years while considering a randomized block design in a factorial arrangement to quantify the effects of genotypes, crop years, and the interaction between these two factors. Coffee fruit samples in the cherry stage were used to evaluate the weights, volumes, and dimensions of the fresh fruit and beans after drying. Genotypic variance prevailed over environmental variance for all of the fruit and bean physical traits of the coffee plants, except for the greatest fruit width (FWG). These associations indicate that the constituent parts of the fruit increased in a manner proportional to an increase in weight. Such associations can facilitate or hinder plant selection. The total gains obtained through the selection indices were similar to those obtained through direct selection for greater bean weights. However, the use of selection indices made it possible to identify clones with more balanced traits. [ABSTRACT FROM AUTHOR]

Inner Mongolia Cashmere goats are excellent genetic resources in China. Cashmere yield/body weight (g/kg), staple diameter (It is the cross-sectional diameter of coarse wool)/staple length (μm/cm), and fiber diameter (It is the cross-sectional diameter of fluff)/fiber length(μm/cm) were studied as secondary traits. Using the CORR and REG programs of SAS9.2, it was found that there is a significant phenotypic correlation and regression between the three secondary traits. The variance components analysis and genetic parameters estimation using the AIREML of the WOMBAT software. The results showed that all secondary traits have moderate heritability (0.17–0.30), and the heritability of each secondary trait of the long staple type is higher than other types. The genetic correlation of each secondary trait is between −0.39 and 0.27, and the genetic correlation of each secondary trait increases with the increase of staple length. Therefore, selection staple length can be to indirect selection of secondary traits. [ABSTRACT FROM AUTHOR]

White markings are characteristic of many equine breeds, being quite common in the Pura Raza Español horses (PRE). These white markings are the result of a lack of melanocytes in the skin and hair. In certain horse breeds, such as the PRE, the presence and extension of white facial markings is penalised in the breed's patron and morphological competitions, so it would be interesting to include it in their selection genetics programs to select against the presence of this special feature. The aim of this study was to calculate the prevalence of white facial markings in a representative population sample of PRE and determine its prevalence depending on the coat colour, its genetic parameters and the influence of systematic effects. The white facial markings have been classified into 5 score. A total of 42,080 PRE horses were analysed. Genetic parameters were estimated using a Bayesian procedure with the BLUPF90 software. Systematic effects included in the model were: birth period, sex, birth stud geographical area and inbreeding coefficient. The pedigree information included 93,322 horses. The prevalence was 34.2%. Systematics factors were significant in the presentation of facial white markings. Heritability in real scale ranged from 0.53 for black to 0.32 for the chestnut coat colour population, both in the linear heterogeneity model. White facial markings were more prevalent in inbred chestnut males of Spain. The additive genetic base shows that the prevalence could be managed by genetic selection. HIGHLIGHTS: PRE with white marks produce financial losses and those that invade a large portion of the eye orbit cannot registered as animals of the breed The prevalence was 34.2%, being the large white markings more affected by systematic risk effects. Genetic base of white facial markings in PRE is very related with the coat colour, and presents high-moderate heritability. White markings could be reduced by genetic selection using breeding values in all the PRE horses as a selection criterion into its breeding program. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the most important risk factors that influence productive life (PL) and to estimate genetic parameters for PL using a Weibull proportional hazards model in two Spanish dairy goat breeds belonging to different production systems. The dataset consisted of 70,695 and 49,176 lactation records of Florida and Payoya females, respectively, collected over the last two decades. A total of 6,227 (24.21%) Florida and 3,452 (20.42%) Payoya females had censored information. The pedigree included a total of 56,901 animals for Florida and 59,957 for Payoya. The effects included in the model for both breeds were the age at first kidding and the herd-year-season of birth of the doe as time-independent effects; and the age at kidding, the herd-year-season of kidding, the within-herd class of milk production deviation and the combination between the lactation number and the duration of lactation as time-dependent effects. Estimation of genetic parameters was made using a Weibull proportional hazards model using Survival Kit V6.0 software. The results from the Weibull animal models gave estimates of additive genetic variances of 0.99 ± 0.0003 and 0.156 ± 0.021, which corresponds to a heritability of 0.43 ± 0.025 and 0.11 ± 0.021 for Florida and Payoya, respectively. The magnitude of heritability obtained for PL suggests that a substantial response to selection may be expected for longevity, especially in the Florida breed. These results may contribute to the development of a routine genetic evaluation to improve PL in Spanish dairy goat breeds. HIGHLIGHTS: A Weibull proportional hazards model has been used to analyse productive life in Spanish goat breeds raised under different production systems. Productive life is influenced by many factors, with milk production the most important. According to the heritability estimated, a significant genetic response could be obtained by direct selection for productive life, especially in the Florida breed. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to estimate genetic parameters for serum insulin-like growth factor I concentrations and their correlations with performance traits in beef cattle. A divergent selection experiment for this important hormone began in 1989. From the 2009 through to the 2017 breeding season, the selection criterion in the two lines was changed to high vs. low maintenance energy expected progeny differences. Estimates of direct heritability were moderate, ranging from 0.34 ± 0.07 to 0.46 ± 0.07 for insulin-like growth factor I concentrations and from 0.32 ± 0.05 to 0.39 ± 0.07 for the growth traits. The heritability of maternal genetic effects for insulin-like growth factor I concentration ranged from 0.02 ± 0.11 to 0.17 ± 0.05 and was similarly low for the weight traits. Maternal permanent environmental effects were negligible for insulin-like growth factor I but were somewhat larger for the weight traits. Direct maternal correlations for postweaning insulin-like growth factor I concentrations were approximately −0.90. The genetic correlations of insulin-like growth factor I with weight traits were generally positive but small. Environmental and phenotypic correlations between insulin-like growth factor I concentrations and growth traits were generally low, indicating that shared environmental influences are minimal, and that this hormone has a modest impact on growth traits. These findings suggest that while IGF-I concentration has some influence, it is not the primary determinant of weight gain or hip height. This study investigated the genetic parameters for serum IGF-I concentrations and growth traits in beef cattle. A divergent selection experiment for serum IGF-I concentration was initiated in 1989. One hundred spring-calving (50 high line and 50 low line) and 100 fall-calving (50 high line and 50 low line) black Angus cows with unknown IGF-I concentrations were randomly assigned to the two divergent selection lines. For the 2009 through 2017 breeding seasons, the selection criterion in the two lines was changed from serum IGF-I concentration to high vs. low maintenance energy expected progeny differences (ME EPDs). The number of records available for analysis varied from 2056 for IGF-I concentration on day 42 of the postweaning performance test to 2988 for birth weight, with the exception that only 617 records were available for IGF-I concentration at weaning. (Co)variance components were estimated for direct and maternal additive genetic effects using an animal model and multiple-trait, derivative-free, restricted maximum likelihood (MTDFREML) computer programs. Direct heritability estimates for serum IGF-I concentrations ranged from 0.34 ± 0.07 to 0.46 ± 0.07, whereas direct heritability estimates for weight traits ranged from 0.32 ± 0.05 to 0.39 ± 0.07. Maternal genetic effects on IGF-I were low, with estimates ranging from 0.02 ± 0.11 to 0.17 ± 0.05, and were similarly low for weight traits. Maternal permanent environmental effects were negligible for IGF-I but were larger for weight traits, especially for weaning weight (0.22 ± 0.04). Direct maternal correlations for postweaning IGF-I concentrations were approximately −0.90. The genetic correlations of IGF-I with weight traits were generally low, with negative correlations observed for birth weight and small positive correlations for the other weight traits. Environmental and phenotypic correlations between IGF-I concentrations and growth traits were generally small, indicating circulating IGF-I has a modest impact on growth traits in beef cattle. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate the best covariance function structure, by means of Legendre polynomials using random regression models (RRM) to describe the genetic variability of the weight growth trajectory of quails and to estimate the genetic parameters. Body weight records of animals at 7, 14, 21, 28, 35, and 42 days of age were used. The orders of fit of the polynomials were gradually increased in orders from 3 to 6 for comparison between the models the Akaike information criteria were used. The models included fixed effects of the contemporary group, the fixed regression coefficient of weight on the Legendre polynomial, random regression coefficients of the direct additive genetic, and the permanent environment effects of the animal, in addition to the residual random effect. The RRM with orders five for the additive genetic effect and six for the permanent environment effect, under the assumption of homogeneity, was the most suitable to describe the genetic variability of the birds’ ponderal growth. There was greater expression of additive genetic variability after 21 days, resulting in distinct and increasing heritability estimates between two periods in ponderal development. Estimates of additive genetic correlations for weights between the ages evaluated indicated that genetic associations are more correlated between body weights at closer ages when compared to ages more distant along the growth trajectory. Thus, it is concluded that selection in birds is more efficient from 28 days of age due to the higher heritability values. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The aims of this study were to estimate the genetic parameters of clinical mastitis (CM) and SCS traits, and to compare the performance of genetic evaluations of CM traits using univariate and bivariate analyses (CM-SCS). Data were edited according to the Udder Health Golden Standard harmonization, and then 6 CM traits and 6 SCS traits were considered, as the result of combining 3 lactation classifications (1, 2, ≥3) and 2 milking periods (early, late). The linear mixed animal models included the ratio of period at risk as a covariate, herd-year of calving, month of calving, and lactation-age as fixed effects, and the permanent environmental effect for traits of ≥3 lactations. Prevalence of CM in early lactation was similar regardless the lactation number (5%–6%), and the estimated heritabilities were 0.01. Prevalences in late lactation ranged from 10% to 24% and heritabilities ranged from 0.03 to 0.05. Estimated heritabilities of SCS ranged from 0.06 to 0.16 with univariate analyses. Somatic cell count (therefore its log-transformation SCS) showed a higher probability of correctly identifying healthy cows than infected cows but there was still up to 36% of healthy cows for which CM was not detected by SCS. Genetic correlations between CM-SCS traits ranged from 0.36 to 0.95, and SCS in lactation 3 and later did not add extra information to SCS in the second lactation for predicting CM. Regarding reliabilities of EBVs for CM traits, bivariate CM-SCS analyses led to substantial increases with respect to the single-trait model for sires (7%–12% more in first lactation and 16%–28% more for second lactation). Sire's rank correlations for CM between univariate and bivariate analyses (0.47–0.92) suggest that discarding sires could be more accurate than selecting candidates for sires of dams. We can conclude that SCS in first lactation could be useful to supplement CM data in first and second lactations to improve udder health genetic evaluation. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Traits related to calving have a significant impact on animal welfare and farm profitability in dairy production systems. Identifying genomic regions associated with calving traits could contribute to refining dairy cattle breeding programs and management practices in the dairy industry. Therefore, the primary objectives of this study were to estimate genetic parameters and perform GWAS and functional enrichment analyses for stillbirth, gestation length, calf size, and calving ease traits in North American Jersey cattle. A total of 40,503 animals with phenotypic records and 5,398 animals genotyped for 45,101 SNPs were included in the analyses. Genetic parameters were estimated based on animal models and Bayesian methods. The effects of SNPs were estimated using the single-step GBLUP method. The heritability (SE) estimates ranged from 0.01 (0.01) for stillbirths in heifers to 0.11 (0.01) for gestation length in cows. The genetic correlations ranged from −0.58 (0.11) between calving ease and stillbirths in heifers to 0.44 (0.14) between calving ease and calf size in cows. Calving ease showed the highest genetic correlation between heifers and cows, 0.8 (0.22) respectively. The candidate genes identified, including MTHFR , SERPINA5 , IGFBP3 , and ZRANB1 , are involved in key biological processes and metabolic pathways related to the studied traits. Reducing environmental variation and identifying novel indicators of reproduction traits in the Jersey breed are needed given the low heritability estimates for most traits evaluated in this study. In conclusion, this study provides a characterization of the genetic background of calving-related traits in Jersey cattle. The estimates obtained can be used to improve or build selection indexes in Jersey cattle breeding programs in North America. [ABSTRACT FROM AUTHOR]

Insect production for food and feed presents a promising supplement to ensure food safety and address the adverse impacts of agriculture on climate and environment in the future. However, optimisation is required for insect production to realise its full potential. This can be by targeted improvement of traits of interest through selective breeding, an approach which has so far been underexplored and underutilised in insect farming. Here, we present a comprehensive review of the selective breeding framework in the context of insect production. We systematically evaluate adjustments of selective breeding techniques to the realm of insects and highlight the essential components integral to the breeding process. The discussion covers every step of a conventional breeding scheme, such as formulation of breeding objectives, phenotyping, estimation of genetic parameters and breeding values, selection of appropriate breeding strategies, and mitigation of issues associated with genetic diversity depletion and inbreeding. This review combines knowledge from diverse disciplines, bridging the gap between animal breeding, quantitative genetics, evolutionary biology and entomology, offering an integrated view of the insect breeding research area and uniting knowledge which has previously remained scattered across diverse fields of expertise. [ABSTRACT FROM AUTHOR]

Increasing global temperatures and the incidence of extreme weather conditions will result in heat stress becoming a greater issue in production animals. Genetic selection and breeding for heat-tolerant animals have been promoted as a possible mitigation strategy in dairy cattle. The objectives of this study were to obtain in-field skin temperature measurements of the eye, muzzle and udder using infra-red thermography to examine the genetic variation in skin temperature within cows of a dairy herd and to estimate the genetic correlations between skin temperature and production traits. Thermal images and herd test records were obtained for the dairy herd at Massey University’s dairy farm 1. Estimates of (co)variances were obtained using the JWAS program with univariate and bivariate animal models. The heritability estimates for the eye, muzzle and udder temperature were low to moderate at 0.20, 0.24 and 0.39, respectively. All genetic correlations between production and temperature traits were positive except for eye temperature with milk yield and protein yield which was negative and weak. These results indicate that it may be possible to select for a greater skin temperature, however, these results need to be validated using a larger sample size. [ABSTRACT FROM AUTHOR]

Simple Summary: The pH is an important indicator in evaluating the quality of goose meat. SNP genotyping combined with genome-wide association studies (GWAS) is a common method for gene mining related to meat quality traits and has been widely applied in animal breeding research. However, gene mining studies focusing on goose meat quality traits have not yet been conducted. To explore the genetic characteristics of pH traits in goose meat, it is essential to study the SNPs and key candidate genes associated with the pH traits of Sichuan White Goose. In this study, we analyzed 203 male Sichuan White Geese. The results showed that 30 SNPs were associated with the pH traits of Sichuan White Goose meat, and 14 key candidate genes were identified. Our research provides a new perspective for improving goose meat quality and advancing molecular breeding practices. The genetic regulation of goose meat quality traits remains relatively unexplored, and the underlying mechanisms are yet to be elucidated. This study aims to employ single nucleotide polymorphism (SNP) genotyping in conjunction with genome-wide association studies (GWAS) to investigate critical candidate regions and genes associated with the pH trait of meat in Sichuan white geese. A cohort of 203 healthy male Sichuan white geese was randomly selected and slaughtered at 70 days of age. Measurements were taken of meat pH, growth parameters, body dimensions, and post-slaughter traits. High-throughput sequencing on the Illumina HiSeq X Ten platform facilitated gene resequencing and SNP evaluation, and GWAS was employed to detect key genes within quantitative trait loci (QTL) intervals. The sequencing of 203 individuals yielded a total of 2601.19 Gb of genomic data, with an average sequencing depth of 10.89×. Through GWAS analysis, a total of 30 SNPs associated with pH were identified. These SNPs were identified on multiple chromosomes, including on chromosome 17 (chr: 23.57–23.68 Mb) and chromosome 13 (chr13: 31.52–31.61 Mb). By annotating these associated SNPs, nine candidate genes (including C19L2, AMFR, POL, RERGL, ZN484, GMDS, WAC) associated with the pH of goose meat were identified. The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) genotyping of 10 SNPs centered on these nine candidate genes was confirmed. GO enrichment analysis revealed that genes within 1 Mb of the associated SNPs are significantly enriched in pathways involved in lymphocyte activation, in response to hydrogen peroxide, Salmonella infection, and other metabolic processes. This study explores the gene regulatory pathways influencing pH traits in goose meat and provides molecular markers for enhancing meat quality. These findings are expected to facilitate the advancement of molecular breeding programs in geese. [ABSTRACT FROM AUTHOR]

The study of adaptability, stability, and productivity is essential for selecting and recommending superior genotypes. This fact is particularly the case for the introduction of common bean cultivars in Rio de Janeiro, Brazil, whose production is negligible and does not meet the internal demand. Thus, this study estimated genetic parameters and selection gains and undertake a simultaneous selection for adaptability, stability, and productivity in black bean genotypes via mixed models. The investigation was carried out in three municipalities in the state of Rio de Janeiro during three crop years. The trials were set up in a randomized block design with 11 genotypes and three replications. High mean heritability (81%) and selection accuracy (90%), as well as good selection prospects, were observed. Gains between 1.03 and 9.49% were achieved for grain yield. Simultaneous selection was efficient, indicating two black bean lines (CNFP 15290 and CNFP 15361) as the most productive, adaptable, and stable. As such, these lines have the potential to be released as new black bean cultivars for the state of Rio de Janeiro. [ABSTRACT FROM AUTHOR]

ABSTRACT Electronic feeders record feeding behaviour as feed events by tracking the animal's in‐out visits to the feeder. Another way to measure feeding behaviour is based on meals. However, the two approaches provide different outcomes. The objectives of this study were to estimate genetic parameters (heritabilities and genetic and phenotypic correlations) for feed event and meal traits, and their genetic and phenotypic correlations with feed efficiency traits in Nellore cattle. The present study analysed six feed event traits (DMIFE: dry matter intake per feed event, FED: feed event duration, TBFE: time between feed events, FTd: feeding time per day, FEd: feed events per day, and FR: feeding rate), six meal traits (DMIME: DMI per meal, MED: meal duration, TBME: time between meals, MC: meal criterion, MTd: meal time per day, and MEd: meals per day), and three feed efficiency traits (ADG: average daily gain, DMI, and RFI: residual feed intake). The traits were measured in feed efficiency tests of Nellore cattle (age = 280 ± 41 days and body weight = 258 ± 47 kg at enrolment). The MC was calculated for each animal and ranged from 1.70 to 64.0 min, i.e., any pair of feed events separated by less than the MC value was considered part of the same meal. The heritabilities and correlations were estimated by fitting univariate and bivariate animal models, respectively, using single‐step genomic BLUP. The highest heritabilities for feed event traits were 0.35 ± 0.06 (FED), 0.39 ± 0.06 (FTd), and 0.50 ± 0.05 (FTd), and for meal traits were 0.31 ± 0.06 (MED) and 0.45 ± 0.06 (MTd). The genetic correlation between feed event traits and meal traits were weak. FR, FED, and FTd had moderate genetic correlations with RFI (−0.56 ± 0.11, 0.44 ± 0.11, 0.60 ± 0.08, respectively). These results indicate that more efficient animals spent less time at the feeder per feed event and per day, and eat faster compared to less efficient animals. In conclusion, feed event and meal traits must be treated as distinct groups of traits since the genetic and phenotypic correlations were, in general, weak to moderate. Among feed event versus meal traits, feed event traits are more favourable to explain the genetic relationships of feeding behaviour with feed efficiency‐related traits. [ABSTRACT FROM AUTHOR]

To evaluate the expression of drought tolerance for bread wheat, six parents diverse in their response to drought i.e., Giza 171 (P1), Sakha 95 (P2), Bohouth 6 (P3), Cham 8 (P4), Gemmiza 12 (P5) and Masr 3 (P6) and their 15 F1 crosses at 100% water requirements, and 70% water requirements sown in randomized complete blocks design season 2023/24 to estimate some genetic parameters for day to heading, days to maturity, chlorophyll pigments, superoxide dismutase activity, the activity of ascorbate peroxidase, proline content, number of spikes/plant, number of grains/spike, 100-kernel weight, and grain yield/plant. slightly significant differences were shown for most studied traits across all water regimes. The ratios of general combining ability to specific combining ability exceeded one for the examined traits, with some exceptions, signifying the influence of additive gene effects on the inheritance. The parental genotypes as good combiners, for earliness were P1 under both treatments, as well as P1, P2, and P3 at 70% water requirements, for physiologic and agronomic traits. The crosses P3 × P4 and P4 × P6 were the best combinations across the two treatments depending on physiological response and yield attributes. Most hybrids had significant heterotic values for agronomic and biophysiological traits. The genotypic and phenotypic coefficients of variation varied from 1.71% for days to maturity to 14.83% for proline content, and from 1.90% for days to maturity to 16.64% for the activity of ascorbate peroxidase under well-watered, respectively; likewise, from 2.03% and 1.80% for days to maturity to 14.69% and 14.05% for chlorophyll a, respectively under water deficit. [ABSTRACT FROM AUTHOR]

The six-population model supports the development of strategies for selecting genotypes with enhanced heat tolerance and yield stability, which are crucial for wheat improvement programs targeting adverse climate conditions. This study was dedicated to exploring the genetic control and heterosis of earliness, physiological, and yield traits under optimum and late sowing dates. The used plant material was six populations (P1, P2, F1, F2, BC1, and BC2) derived from two crosses of bread wheat; Cross І (Line 606 × Sakha 95) and Cross П (Cham 8 × Masr 3). The results displayed highly significant mean squares due to generations. Heterosis estimates were negative and significant for earliness traits and positively significant for the remaining traits, with a few exceptions. Moreover, at least one of the non-allelic interactions is significant or highly significant, proving the appropriateness of the six parameters model to estimate the different gene effect types governing most studied characters. However, the simple additive-dominance genetic model clarified the inheritance of the number of spikes/plant and days to maturity in cross І (Line 606 × Sakha 95), and number of spikes/plant and number of grains/spike in cross П (Cham 8 × Masr 3) at late sowing. Heritability estimates are labeled as very high to moderately high in the broad sense and, in the meantime, varied as low, medium, and high in the narrow sense. The expected genetic advance had varied values, which ranged from 4.55% days to maturity at the recommended sowing in the cross П (Cham 8 × Masr 3) to 76.07% for the weight of 100-kernel at the late date in the cross І (Line 606 × Sakha 95). Our findings provide valuable insights for wheat breeding programs targeting enhanced yield and heat tolerance. [ABSTRACT FROM AUTHOR]

The aim of pumpkin breeding programs is to develop cultivars that meet the production, commercial quality, and nutritional value, considering several attributes. Therefore, the objective of this study was to select pumpkin genotypes with high fruit quality for future use in genetic breeding programs. Two production cycles were carried out. The evaluations included the determination of genetic parameters (the additive genetic variance, environmental variance between residual variances and individual phenotypic variance, accuracy of progeny selection, restricted heritability, coefficient of individual additive genetic variation, coefficient of genotypic variation between progenies, coefficient of residual variation, coefficient of relative variation, variance of the prediction error of the genotypic values of the progeny), the prediction of genetic gains, and the selection of genotypes with fruits of better physical and chemical quality attributes. The carotenoid and β-carotene contents of the pulp were distinguished by high values of additive genetic variance, residual variance and individual variance. Additionally, genetic gains were achieved for the main carotenoid compounds, as xanthophyll (68%), lycopene (58%) and β-carotene (49%). In the second production cycle, using the technique of Mulamba and Mock, a new ranking method was used to select the best genotypes. These genetic parameters, especially restricted heritability, indicate the potential for advancing new selection stages to develop pumpkin cultivars with superior qualities, including fruit length (0.976), skin thickness (0.951) and orange pigments, particularly β-carotene (0.894). Additionally, firmer fruits with high ascorbic acid content and a pulp hue angle representing an orange color were ranked among the best genotypes. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. In this paper, we present a comprehensive study of gestation length (GL) in 16 cattle breeds by using large genotype and animal record databases. Data included over 20 million gestations since 2000 and genotypes from one million calves. The study addressed the GL variability within and between breeds, estimation of its direct and maternal heritability coefficients, association with fitness and several economic traits, and QTL detection. The breed average GL varied from 279.7 to 294.4 d in Holstein and Blonde d'Aquitaine breeds, respectively. Standard deviations per breed were similar and ranged from 5.2 to 5.8 d. Direct heritability (i.e., for GL defined as a trait of the calf) was moderate to high (h2 = 0.40–0.67), whereas the maternal heritability was low (0.04–0.06). Extreme breeding values for GL were strongly associated with a higher mortality during the first 2 d of life and were associated with milk production of dams for dairy breeds and precocity of females. Finally, several QTL were detected affecting GL with cumulated effects up to a few days, and at least 2 QTL were found to be shared between different breeds. Our study highlights the risks that would be associated with selection toward a reduced GL. Further genomic studies are needed to identify the causal variants and their association with juvenile mortality and other economic traits. [ABSTRACT FROM AUTHOR]

This study characterizes rosé veal from 412 Danish Blue × Holstein heifer and bull calves and beef from 183 highly marbled culled Holstein dairy cows. Furthermore, it investigates the potential for breeding higher meat quality in dairy crossbreeds via genetic parameter estimation. Carcasses were split between the 5th and 6th thoracic vertebra and the meat quality of M. longissimus thoracis was evaluated for pH, color, cooking loss, Warner-Bratzler shear force (WBSF), and chemical intramuscular fat concentration (IMF%). Genetic parameters were estimated using an animal model. The crossbred bull calves outperformed heifers in carcass characteristics, while heifers were superior in redness, cooking loss, WBSF and IMF%. Heritability was significant for WBSF, cooking loss, and IMF%, indicating that meat quality can be improved through selective breeding. The meat quality of highly marbled Holstein cows did not vary across parities, highlighting them as an under-utilized potential source of high-quality beef from a beef-on-dairy system. [ABSTRACT FROM AUTHOR]

This study aimed to identify stable and productive genotypes of rubber tree [Hevea brasiliensis (Willd. ex. Adr. de Juss. Müell-Arg.)] in water stress using the linear mixed model approach and to compare genetic parameters estimates of different genotypes groups in different years. The experiment was composed of 58 test clones and control clones (RRIM 600, GT 1 and PB 235) distributed across four trials evaluated in the Centro Avançado de Pesquisa e Desenvolvimento de Seringueira e Sistemas Agroflorestais, Votuporanga, São Paulo, Brazil. Rubber yield was evaluated over four years. The crop water stress index (CWSI) was used to evaluate water conditions over the period. The rubber yield data were analysed by the Restricted Maximum Likelihood model and Best Linear Unbiased Prediction (REML/BLUP) procedure. The plant development conditions were inadequate throughout the period. The effect of genotypes was significant in all analyses, indicating conditions favourable to the selection. The superior clones were V 051, V 006, and V 123 (Trial 1); V 227, V 263, and V 288 (Trial 2); V 744, V 619, and V 582 (Trial 3) and C 311, C 344, and C 33 (Trial 4). These genotypes can be used as parental clones in future breeding cycles. There are clones capable of maintaining yield stability in water deficit periods. The annual genetic variability estimated for rubber yield varies from year to year but is maintained during the breeding cycle. This contributes to the maintenance of the genetic variability among productive genotypes. [ABSTRACT FROM AUTHOR]

Simple Summary: Horse body conformation is an important aspect to evaluate in sport horse selection since the overall body shape determines the limits of the range of movement and function of the horse and, ultimately, its future performance. The genetic improvement of this breed is under the control of the National Association of Maremmano Breeders (ANAM), the first Italian association to use a continuous evaluation scale to evaluate the horses enrolled in the Studbook in the early 1990s. Morphological scoring is a common evaluation method for domestic animals. People employed in this type of role must be able to translate their judgements regarding certain features of the animal's body into numbers or letters, thus avoiding the need to measure the animal. Only a few aspects of the horse's body conformation are actually measured since this activity is difficult and expensive. This study proposes an easier approach to horse scoring in order to obtain genetic proof of morphological traits and, consequently, to support breeders in making targeted selection decisions. Three new factors were computed and summed through an unique New Estimated Breeding Value (NEBV1), with the purpose of supporting breeders in adopting an easier and more accurate selection approach. Morphological scoring is a common evaluation method for domestic animals. The National Association of Maremmano Breeders (ANAM) has provided a dataset containing the records of 600 horses, four metric measurements (cm) and 24 traits with a continuous evaluation scale, each one with 15 classes. Moreover, a body condition score (BCS) with five classes is included. In this study, factor analysis was conducted to create a small number of informative factors (3) obtained from these traits, and a new BLUP-AM-MT index was established. The New Estimated Breeding Value (NEBV1) of each horse was computed by adding the genetic indexes of the three factors, with each one multiplied using a coefficient indicated by ANAM. The practical feasibility of the NEBV1 was evaluated through Spearman correlations between the rankings of the NEBV1 and the rankings of the BLUP-AM-MT, estimated through the four biometric measures and the morphological score (MS) assigned to each horse by the ANAM judges. The factorial analysis was used to estimate three factors: the "Trunk Dimension", "Legs" and "Length". As the explained variance was only 32%, the model was rotated, and the heritability of the three factors were 0.51, 0.05 and 0.41, respectively. After rotation, the estimated correlations between the new NEBV1 and the biometric measures were improved. These results should encourage breeders to adopt a breeding value index that takes into consideration the factors derived from all the variables observed in the morphological evaluation of the Maremmano. In this way, breeders can use it to select the best animals for breeding. [ABSTRACT FROM AUTHOR]

There is growing interest in selective breeding of the honeybee, resulting in the emergence of new breeding projects, often with an emphasis on improving resilience traits, in particular toward brood diseases. Lately, feed autonomy is also gaining importance. Here, we use data from a small breeding nucleus in France to estimate genetic parameters for common bee breeding traits and a novel trait reflecting honey reserves in the brood chamber. Open-mated queens were produced each year from inseminated dams between 2019 and 2021, and ~330 colonies were phenotyped each following year at three periods during the entire beekeeping season. Genetic parameters were estimated using ReML with an animal model. Narrow-sense heritability estimates ranged from low (around 0.15) for calmness and total capped brood surface both measured in early summer, to moderate (0.30 to 0.40) for hygienic behavior in spring, honey yield, and phoretic V. destructor load in early summer. Honey reserves in the brood chamber showed an intermediate heritability throughout the season (around 0.25). Gentleness had a null heritability. Most correlations between phenotypes adjusted for environmental fixed effects were close to zero. Among exceptions, there were honey reserves in the brood chamber in early summer with honey yield (around −0.2) and with the total capped brood surface in early summer (around −0.3). These estimates, although uncertain due to the dataset size, suggest that selection for production and resilience will be effective, even though simultaneous selection for honey yield and feed reserves might be difficult due to a possible genetic antagonism between both traits. [ABSTRACT FROM AUTHOR]

This study carried out early selection of soybean progenies that are productive and resilient to environmental conditions. The experiment took place at the Genetic Breeding Program of UNIJUI (University of the Northwest of the State of Rio Grande do Sul), located in Ijuí - RS, Brazil. The experiment used augmented blocks design with interim checks. The regular treatments correspond to 24 soybean F2 populations and the common treatments were 18 commercial checks, arranged in four replications. At full physiological maturity, in each experimental unit, five plants were randomly collected to obtain seed weight per plant (SWP, g). The Jinks and Pooni methodology was used to calculate the probability of extracting superior lineages from the evaluated populations. The best control and promising cultivars to compose the parent bank are BMX FORÇA RR, FUNDACEP 66 RR and TMG 7062 IPRO. Jinks and Pooni's methodology identified populations IRC001, IRC002, IRC017, IRC019, IRC028, IRC030, IRC032, IRC033, IRC035, IRC036, IRC039 and IRC040 as having high potential for extraction of superior lineages. [ABSTRACT FROM AUTHOR]

This paper aimed to estimate the heritability and genetic correlations for processability (milk coagulation properties, cheese yield, and heat stability), milk production, and milk composition of dairy sheep in a New Zealand flock. Test-day records from 169 ewes were obtained during the 2021–2022 season. Heritability estimates for yield traits (milk, fat, protein, and lactose yield) were moderate and ranged from 0.33 to 0.38. Whereas heritability estimates for processability traits were lower and ranged from 0.17 to 0.27. The genetic correlations indicated that poorer milk coagulation properties were associated with lower mammary health indicated by higher SCS, higher pH, and lower lactose content. Additionally, a higher ratio of casein to calcium i.e. lower availability of soluble calcium was associated with poorer milk coagulation properties. Higher yields of milk, fat, protein, and lactose were associated, but to a smaller degree, with better MCP. It is proposed that genetic improvement of dairy sheep for higher yields of fat and protein, and for lower SCS, could indirectly improve milk processability for cheese-making. However, it is recommended that larger studies involving more dairy sheep flocks are conducted to validate the present results before developing a selection index for this industry. [ABSTRACT FROM AUTHOR]

Germplasm collections for breeding purposes must initially be characterized to evaluate the diversity and allow the selection of materials for specific environments and uses. Stylosanthes scabra Vog. is a legume forage from the Brazilian Tropical Semiarid region, which might have potential, but is still underknown. The treatments consisted of eight S. scabra accesses (F1 generation) from Bom Jardim Municipality, in the tropical semiarid region in Brazil, on a complete randomized block design, with three replications. Qualitative and quantitative morphological descriptors and anthracnose incidence were evaluated at 30-day intervals, while forage mass was evaluated through cuts every 60 days, totaling three cuts. Frequency analysis by access was performed on qualitative variables and analysis of variance and Friedman on quantitative variables with subsequent Tukey test (p < 0.05) when appropriate. Genetic parameters were estimated for qualitative and quantitative descriptors. The accesses of S. scabra were different (p < 0.05) for all evaluated descriptors except for plant height, with high heritability (> 62.8%) and low repeatability (0.2 to 0.6). The high morphological diversity, even on a relatively small collection from a single tropical semiarid municipality, indicates the possibility of selecting superior materials. [ABSTRACT FROM AUTHOR]

We estimated genetic parameters of two Pinus caribaea var. caribaea progeny tests based on growth traits aiming at the identification of the best selection strategy. This study was conducted in two progeny tests located in Selvíria (MS), Brazil. Tests were set up in block design, one with 76 progenies (area 1) and the other with 99 progenies (area 2). Genetic parameters were estimated using the SELEGEN software through REML/BLUP method. To estimate the genetic gain through selection, four selection methods and ten selection intensities were tested. The intensity of selection that maximizes genetic gain and genetic diversity was calculated by the optimization point. Significant variation was observed between and with progeny for all traits in area 2 and only within plots for height in area 1. Higher values of heritability were observed in area 1. Considering the optimization of selection, the best selection method for both areas was the individual. [ABSTRACT FROM AUTHOR]

Eucalyptus pilularis Smith is renowned for its high-quality wood, rapid growth, and adaptability to diverse soil conditions. This study aimed to evaluate the use of the molecular kinship matrix to estimate genetic parameters for E. pilularis selection and the potential establishment of a base population. The experiment involved 13 provenances and 115 progenies, using a randomized complete block design with five replicates and linear plots consisting of five plants each. Genetic parameters for the traits diameter at breast height (DBH), total height, and volume were evaluated at five years of age using the linear mixed model. Results indicated a survival rate for the population of 73.11%, an average total height of 18.65 m, DBH of 14.28 cm, and volume of 14.57 cm3. By adjusting the kinship matrix, the estimated values of heritability and genetic coefficients of variation decreased, indicating that there would be errors in these estimates and in the genetic gains if the progenies were assumed to be half-siblings. The discrepancy in rankings derived from the conventional half-sibling matrix versus molecular kinship matrix poses a significant challenge for experts in forest species genetic improvement. Our findings indicate not only inflated estimations of genetic parameters and gains, but also disparities in rankings when accounting for true levels of relatedness among individuals based on the molecular matrix. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate genetic effects on parameters of the Brody and Richards growth curves using body weight records from birth to 12 months of age on 2287 Muzaffarnagari lamb for a period of 29 years (1976–2004). Estimated growth curve parameters were analysed using six univariate animal models, and genetic correlations among and between the parameters of each function and between parameters of the functions and observed birth and yearling weights were estimated using bivariate analyses. Significant environmental factors including birth year, sex, season, birth status and dam parity were included as fixed effects in all models. Likelihood ratio tests indicated that maternal genetic effects were significant only for birth weight (BW) and degree of maturity at birth (u0) for the Brody and Richards functions. For these traits, direct heritabilities were similar (0.21, 0.19 and 0.17, respectively), but the estimated maternal heritability for BW (0.18) was twice that of u0 for both functions. Heritabilites for yearling weight and asymptotic final body weights for the Brody and Richards functions were 0.28, 0.17 and 0.21, respectively. The remaining growth curve parameters were lowly heritable, ranging from zero for the predicted degree of maturity at the age of maximum growth rate for the Richards function to 0.08 for the maturing rate parameter of the Brody function. Genetic correlations between corresponding parameters for different growth functions exceeded 0.88. Our results showed that the Brody and Richards functions had similar genetic architecture, but the Richards function had no apparent advantages over the more easily interpreted Brody function. Failure to identify maternal genetic effects on maturing rate parameters suggested that both functions failed to identify potentially important maternal genetic effects. Therefore, there is no usefulness of estimated growth curve parameters in selection compared to the simple multi‐trait genetic evaluations of individual body weights. [ABSTRACT FROM AUTHOR]

The study aimed to assess performance traits in Hardhenu cattle by analysing data from 445 animals born to 59 sires and 227 dams. The investigation focused on estimating (co)variance components and genetic parameters for reproduction and production traits in dairy cattle. Results from least‐squares analysis indicated a significant effect (p <.01) of the period of calving (POC) on key production traits, including first lactation milk yield (FLMY), 300‐day milk yield (FLMY300), first peak yield (FPY) and total lactation milk yield (TLMY) in studied population. The least squares means for these traits were reported as follows: FLMY (2665.68 ± 45.66 kg), FLMY300 (2425.52 ± 34.41 kg), FLL (312.95 ± 3.83 days), FPY (11.52 ± 0.15 kg) and TLMY (9282.44 ± 167.03 kg) in Hardhenu cattle. In the studied population, only additive genetic variability was found to be present and there was absence of any significant maternal effect with respect to targeted traits in the resource population. Direct heritability estimates (h2) for FLMY, FLMY300, FLL, FPY, TLMY and other traits ranged from 0.03 to 0.41 in Hardhenu cattle. These findings offer valuable insights into the genetic factors influencing performance traits, contributing to the enhancement of breeding and management practices in Hardhenu cattle. [ABSTRACT FROM AUTHOR]

Simple Summary: Luzhong mutton sheep, a new breed of sheep used for meat production, are characterized by a fast growth rate, high adaptability, and roughage tolerance. The aim of this study was to estimate the genetic parameters and analyze the genetic trends of early growth traits in Luzhong mutton sheep using different animal models, and Model 4 was identified as the best model. In this study, the greater heritability of weaning weight and higher genetic correlation with key production traits indicated that weaning weight could be used as a selection criterion for late weight traits. In addition, the results of this study indicated that maternal effects had a great influence on early growth traits in Luzhong mutton sheep. In this study, six different animal models were fitted, and the constrained maximum likelihood method was used to assess the genetic parameters and genetic trends of early growth traits in Luzhong mutton sheep. The experimental data of this study included the newborn weight (BWT, N = 2464), weaning weight (WWT, N = 2923), weight at 6 months of age (6WT, N = 2428), average daily weight gain from birth to weaning (ADG1, N = 2424), and average daily weight gain from weaning to 6 months of age (ADG2, N = 1836) in Luzhong mutton sheep (2015~2019). The best model for the genetic parameters of the five traits in Luzhong mutton sheep was identified as Model 4 using the Akaike information criterion (AIC) and likelihood ratio test (LRT) methods, in which the estimated values of direct heritability for the BWT, WWT, 6WT, ADG1, and ADG2 were 0.156 ± 0.057, 0.547 ± 0.031, 0.653 ± 0.031, 0.531 ± 0.035, and 0.052 ± 0.046, respectively, and the values for maternal heritability were 0.201 ± 0.100, 0.280 ± 0.047, 0.197 ± 0.053, 0.275 ± 0.052, and 0.081 ± 0.092, respectively. The genetic correlation between the ADG2 and WWT was negative, and the genetic and phenotypic correlations among the remaining traits were positive. In this study, maternal effects had a more significant influence on early growth traits in Luzhong mutton sheep. In conclusion, to effectively improve the accuracy of genetic parameter estimation, maternal effects must be fully considered to ensure more accurate and better breeding planning. [ABSTRACT FROM AUTHOR]

In this study, a dataset comprising 20,328 body weight records from birth to 360 days of age was utilized to compare five growth curve models and genetic analysis of growth curve parameters in Iran-Black sheep. The data and genealogical information were collected between 1981 and 2007 from the Breeding Station of Abbasabad in the Khorasan Razavi province of northeast Iran. The performance of five statistical models including Brody, negative exponential, von Bertalanffy, Logistic, and Gompertz for describing the growth curve of the studied population was evaluated by applying the SAS software. The statistical measures used for model comparisons were Akaike's information criterion (AIC), root mean square error (RMSE), and adjusted coefficient of determination (R²adj). The Brody model, exhibiting the highest R²adj and the lowest values for both AIC and RMSE, was selected as the best model for characterizing the growth curve in this breed. Consequently, the parameters of the growth curve, including parameter A (considered as weight at maturity), B (considered as an integration constant), and K (maturation rate) were predicted by applying the Brody model. To investigate the effect of maternal components on the growth curve parameters, nine univariate animal models, including different combinations of the direct additive genetic, maternal additive genetic, maternal permanent environmental, and maternal temporary environmental effects, were fitted. Subsequently, two multivariate animal models, comprising the standard (SMM) and fully recursive (FRM) models were analyzed by using the Bayesian inference. The FRM outperformed SMM in terms of lower means square error (MSE) and higher Pearson's correlation coefficients between the actual and predicted records (r(y, y)) values, indicating better goodness of fit. The posterior means for heritability of A, B, and K parameters were low but statistically significant under SMM and FRM. It may be concluded that the growth trajectory traits of Iran-Black sheep are influenced mainly by non-additive genetic and environmental effects, emphasizing the importance of considering these effects for developing the corresponding breeding strategies. The Spearman's rank correlation coefficients between the estimated breeding values for growth curve traits under SMM and FRM indicated significant re-ranking of animals, favoring FRM for genetic evaluation in Iran-Black sheep. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the genetic parameters for age at first calving in Charolais and Limousine cattle breeds using animal model. The reproduction traits are influenced by genetic factors and environmental factors. The genetic factors are breed, individual and environmental factors are: climate condition and nutrition. The data consisted on 239 records for Charolais breed and 309 records for age at the first calving for Limousine breed. The data were from Romanian Breeding Association for Beef cattle. The age at the first calving was 792.92±6.77 days for Charolais breed and 813.83±6.09 days for Limousine breed. The heritability value for age at the first calving was 0.273 for Charolais and for Limousine breed was 0.275. The breeding values of cows with records for age at first calving were between −30.697 and 40.929 for Limousine breed were between −46.64 and 42.65. For improvement the reproduction traits it is necessary to improve the environmental conditions and supervision of reproduction activity in the farms and the selection of the best cows. The selection based on the breeding values of the cows determined the improvement of age at first calving. Improvement the reproduction traits increase the profitability of farms. [ABSTRACT FROM AUTHOR]

The present study aimed to use detailed phenotyping for the claw disorder digital dermatitis (DD) considering specific DD stages in 2 housing systems (conventional cubicle barns [CON] and compost-bedded pack barns [CBPB]) to infer possible genotype × housing system interactions. The DD stages included 2,980 observations for the 3 traits DD-sick, DD-acute, and DD-chronic from 1,311 Holstein-Friesian and 399 Fleckvieh-Simmental cows. Selection of the 5 CBPB and 5 CON herds was based on a specific protocol to achieve a high level of herd similarity with regard to climate, feeding, milking system, and location, but with pronounced housing-system differences. Five other farms had a "mixed system" with 2 subherds, one representing CBPB and the other one CON. The CBPB system was represented by 899 cows (1,530 observations), and 811 cows (1,450 observations) represented the CON system. The average disease prevalence was 20.47% for DD-sick, 13.88% for DD-acute, and 5.34% for DD-chronic, with a higher prevalence in CON than in CBPB. After quality control of 50K genotypes, 38,495 SNPs from 926 cows remained for the ongoing genomic analyses. Genetic parameters for DD-sick, DD-acute, and DD-chronic were estimated by applying single-step approaches for single-trait repeatability animal models considering the whole dataset, and separately for the CON and CBPB subsets. Genetic correlations between same DD traits from different housing systems, and between DD-sick, DD-chronic, and DD-acute, were estimated via bivariate animal models. Heritabilities based on the whole dataset were 0.16 for DD-sick, 0.14 for DD-acute, and 0.11 for DD-chronic. A slight increase of heritabilities and genetic variances was observed in CON compared with the "well-being" CBPB system, indicating a stronger genetic differentiation of diseases in a more challenging environment. Genetic correlations between same DD traits recorded in CON or CBPB were close to 0.80, disproving obvious genotype × housing system interactions. Genetic correlations among DD-sick, DD-acute and DD-chronic ranged from 0.58 to 0.81. SNP main effects and SNP × housing system interaction effects were estimated simultaneously via GWAS, considering only the phenotypes from genotyped cows. Ongoing annotations of potential candidate genes focused on chromosomal segments 100 kb upstream and downstream from the significantly associated candidate SNP. GWAS for main effects indicated heterogeneous Manhattan plots especially for DD-acute and DD-chronic, indicating particularities in disease pathogenesis. Nevertheless, a few shared annotated potential candidate genes, that is, METTL25, AFF3, PRKG1 , and TENM4 for DD-sick and DD-acute, were identified. These genes have direct or indirect effects on disease resistance or immunology. For the SNP × housing system interaction, the annotated genes ASXL1 and NOL4L on BTA 13 were relevant for DD-sick and DD-acute. Overall, the very similar genetic parameters for the same traits in different environments and negligible genotype × housing system interactions indicate only minor effects on genetic evaluations for DD due to housing-system particularities. [ABSTRACT FROM AUTHOR]

Rice length and shape are the important quality traits in rice that affect consumer acceptance and price. Rice length and shape can be improved through crosses followed by selection. Genetic parameters influence effective selection. The research objectives are to estimate genetic parameters for rice length and shape in the F2 population of Basmati Delta 9 x Koshihikari and Basmati Pakistan x Inpago Unsoed 1. F2 rice population from crosses of Basmati Delta 9 (extra-long, slender) x Koshihikari (short, round), Basmati Pakistan (extra-long, slender) x Inpago Unsoed 1 (medium, medium), and the parents are used for research material. The genotype is planted using an experimental design with no replication. Rice length and shape data were collected from each plant. The collected data is used to estimate the genetic parameters of rice length and shape. The results show that polygenes control rice length and shape. Transgressive segregation is obtained in the F2 population of Pakistan Basmati x Inpago Unsoed 1. The genetic diversity of rice length and shape is low, so reducing the selection intensity of these traits is suggested. The estimate of broad sense heritability and genetic gain of rice length and shape was high. [ABSTRACT FROM AUTHOR]

Kale is one of the main leafy vegetables grown in Brazil. However, genetic breeding programs for the development of superior cultivars are scarce. Thus, the objective of this study was to select promising genotypes and to obtain strategic information for the genetic improvement of kale from plant biometrics. The study was conducted in two stages in the horticulture sector of Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) during 2018 and 2019. The university is located in the municipality of Diamantina, state of Minas Gerais, Brazil. The seeds used were obtained from 25 pre-selected half-sib progenies. In 2018, these progenies were recombined, selecting the seeds from plants with superior agronomic performance. Subsequently, in the year 2019, the seeds harvested in the first stage were sown, and the agronomic evaluation of the resulting plants was conducted. The experimental design was randomized blocks with four replicates and six plants per plot. At this stage, agronomic biometrics of the plants were conducted, identifying those with higher productivity and leaf quality. The genetic parameters were estimated, and the genetic gains with selection were predicted. The highest individual heritability in the narrow sense (h2a) was observed for plant height, followed by the mean mass per leaf. The yield of leaves showed gains of 11.80, 10.39, and 7.68% at selection intensities of 10, 15, and 30%, respectively, indicating the possibility of genetic progress with the selection of superior genotypes. The individual selection approach proved effective in improving the population, however, indirect selection for increased leaf number resulted in a reduction in leaf size. [ABSTRACT FROM AUTHOR]

Simple Summary: Limb alignments significantly impact the performance and overall well-being of horses, which means that the identification and management of limb-conformation defects is vital for horse owners and breeders. Our study investigates the prevalence of 14 defects in Menorca Purebred horses, along with the environmental factors influencing their occurrence and the genetic parameters for potential inclusion in the official breeding program. Analysis of data from 1120 records from 509 animals reveals a higher prevalence of defects in older females from breeder studs dedicated to breeding, possibly due to limited care. Notably, splay-footed forelimb, closed hocks, camped under, pigeon-toed forelimb and coon foot are the commonest, with a prevalence exceeding that of other equine populations. These defects significantly influence gait scores, particularly in trotting. Heritability estimates range from 0.12 to 0.30, suggesting genetic influence. Genetic correlations show that careful consideration is needed in selective breeding to avoid unintended outcomes. It is therefore advisable to focus selective efforts on the more prevalent defects with higher heritability, as well as to evaluate the inter-defect relationships. Limb-conformation defects significantly influence equine performance and welfare, necessitating thorough investigation for effective management. This study examines the prevalence and genetic parameters of 14 limb-conformation defects in Menorca Purebred horses using data from 1120 records (509 animals with an average age of 101.87 ± 1.74 months) collected between 2015 and 2023. Defects were evaluated using a three-class scale by three appraisers, and a Bayesian approach via Gibbs sampling was employed to estimate genetic parameters including gender, birth period, stud selection criteria, evaluation age and appraiser as fixed effects. Splay-footed forelimb and closed hocks were the most prevalent defects (67.20% and 62.53%, respectively). Horses with any of the defects analyzed have been observed to obtain significantly lower scores for both walk and trot. Heritability estimates range from 0.12 (s.d.: 0.025) for closed hock to 0.30 (s.d.: 0.054) for base narrow, confirming the genetic influences on the expression of limb conformation defects. The divergent defect in hind limbs showed the highest genetic correlations with forelimb defects (camped under, −0.69; s.d: 0.32 and camped out, 0.70; s.d: 0.27). The significant genetic correlations between defects highlight the complexity of the relationships, which requires careful consideration. [ABSTRACT FROM AUTHOR]

Amylose content (AC) and percentage of chalkiness (PC) are the two most important quality parameters of rice (Oryza sativa L.). Breeding for high-quality medium-grain rice has been a decisive demand for the current market and consumption. This research aimed to study the crossing populations and the selection of early generations of promising combinations for evaluation in the next generations. The crossing populations' assessment ensued for genetic variability (PCV and GCV), heritability (h²BS), and genetic advance (GAM) for the related traits. The promising rice population's election for pure lines employed marker-assisted selection (MAS). The result showed three promising maternal cultivars (PY2, Sieu Ham Chau, and ML202) and paternal cultivars (M-202, Saturn, and Palmyra). Through the analysis of genetic parameters in the rice F2 populations, the cross combination of ML202/M-202 was the choice because of its valuable genetic parameters expected with PCV and GCV ≥ 20%, h²BS ≥ 60%, and GAM ≥ 20% for both traits of AC and PC. The Chi-square test of the variables AC and PC in the cross-population ML202/M-202 indicated the segregated ratios of 3:1 in the phenotype and 1:2:1 in the genotype. Applying MAS to select the promising rice F2 populations resulted in 92 individuals carrying genes identified with low AC and PC simultaneously. These individual rice genotypes became options for evaluation in the next generations. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate genetic parameters of somatic cell score (SCS) and fat plus protein yield (FPY) using repeatability (RM) and random regression (RRM) models in Florida goats. The data consisted of 340,654 test-day controls of the first three lactations, and the pedigree contained 36,144 animals. Covariance components were estimated with a bivariate RM and RRM using the REML approach. Both models included as fixed effects the combination of herd and control date, litter size, kidding number and lactation length, and as random effects, the additive genetic and permanent environmental effects. A variation in the shape of the genetic parameters along the lactation curve was observed for both traits, and h2 oscillated between 0.272 and 0.279 for SCS and 0.099 and 0.138 for FPY. The genetic correlation between SCS and FPY was negative and medium (−0.304 to −0.477), indicating that a low-SCS EBV is associated with a genetic predisposition to high FPY production. Our results showed that given the magnitude of h2 for SCS and its rg with FPY, the SCS could be used as a selection criterion to increase resistance to mastitis, thus obtaining an improved dairy and cheese aptitude in this breed. [ABSTRACT FROM AUTHOR]

The aim of this study was to infer the effects of heat stress (HS) of dams during late gestation on direct and maternal genetic parameters for traits related to milk production and milk quality parameters (90,558 records) in Italian Brown Swiss cattle (12,072 cows in 617 herds). Daily average temperature-humidity indices (THI) during the last 56 d of pregnancy were calculated, using the climate data from the nearest public weather station for each herd. Heat load effects were considered as the average across the entire periods considering a thermoneutrality condition for data below the THI 60. For parameter estimation a random regression model using the second-order Legendre polynomial regression coefficient for THI considering both animal and maternal effect for heat load. Direct heritability increased sharply from THI 60 to 65, then decreased gradually up to THI ∼72, and sharply thereafter. Maternal heritability showed a different trend, with values close to 0 up until to THI 65 and slightly increasing toward extreme THI values. The study suggests a lower threshold of THI 60 for the onset of HS. Higher heritability values indicate greater selective efficiency in the THI range of 65 to 70, even if a higher standard deviation value have been detected. The effects of high THI during intrauterine life varied among traits with different heritability levels. Genetic correlations for milk, fat, and protein content at 60 THI with increasing value of environmental variable, remained constant (∼0.90) until THI >75, where they slightly decreased (∼0.85). Fat and protein yields, as well as milk and energy-corrected milk, showed correlations dropping to 0.80 around THI 67 to 68 and stabilizing between 0.75 and 0.85 at extreme THI values. Maternal component correlations dropped close to zero, with negative values for protein content at THI 65 to 70. Antagonism between direct and maternal components was stronger for intermediate THI values but less divergent for extremes. Genotype by environment interaction was observed, indicating the selection of resilient animals would be theoretically possible. In the future, the application of climate variables in selection schemes first should take into account the dimensions of the genetic correlations to be able to decide between the simple inclusion of the environmental effect in the statistical models, rather than a real parallel genetic evaluation. [ABSTRACT FROM AUTHOR]

Pecan (Peganum harmala L.) has many characteristics, such as antibacterial, antioxidant, antifungal, anticancer drugs, etc. In different genetic analyses, the calculation of the genotype correlation coefficient is more important than the phenotype correlation coefficient. Similarly, the use of other genetic parameters (such as heritability, etc.) is very useful in plant breeding projects. Therefore, it is not correct to choose the ecotype (genotype) with the help of other traits without considering the relationship and calculating the correlation between the traits, it strongly affects the desired results. For this research, First, pecan plant samples were identified and collected simultaneously. In this study, the pecan ecotypes identified in habitats (Three habitats in Asadabad-Hamedan including Mousi-Abad Village 1, Mousi-Abad Village 2 and Najaf-Abad Village, and the fourth habitat in Kangavar -Kermanshah include Karkhaneh Village (located in the west of Iran) traits related to the morphology of the pecan plant were evaluated. In order to calculate the genetic correlation and other genetic parameters, the form of random complete block design is designed and implemented with three replications. The genetic correlation coefficients calculated in this study indicated that there is a genetic correlation between traits associated with yield. In addition, the maximum percentage of heritability was assigned to the traits of number of branches per plant (0.99%) and stem diameter (0.99%), and the minimum percentage of heritability was assigned to the traits of number of nodes (0.24%) and fresh weight of a single stem (0.0009%), respectively. The stem diameter trait had the maximal heritability value and also had the maximal genetic advance rate. Also, the traits of number of nodes, fresh weight of whole plant and fresh weight of single stem, in addition to having the lowest heritability, had the lowest genetic advances. [ABSTRACT FROM AUTHOR]

The main goal of the Belgian Warmblood horse studbook (BWP) is to breed successful competition horses, with emphasis on show jumping. However, competition results are only available later in life and competition traits are lowly heritable. Hence, the use of phenotypes that record performance‐related traits at an early life stage could help increase genetic progress. In this study, we evaluated the potential of eleven linear scored early life jumping traits assessed during jumping in freedom (2–5 years old) or under the saddle (4–6 years old) as proxies for later success in show jumping competitions. To this end, we estimated their heritabilities and genetic correlations with the competition trait, adjusted fence height, by using 2170 free jumping records, 1588 jumping under saddle records, 674,527 show jumping competition records and almost 81,000 informative horses in the pedigree. As participation of young horses in these contests is on a voluntary basis, a pre‐selection most probably exists. To verify this hypothesis, we investigated the association between participation to young horse contests and participation to show jumping competitions later on (called here start status phenotype). We also estimated heritabilities for "start status in free jumping contest", "start status in jumping under saddle contest" and "start status in free jumping or jumping under saddle contest" by fitting threshold models. Furthermore, we calculated genetic correlations between these traits and adjusted fence height and calculated the correlations between EBVs for start status in young horse contests and EBVs for success in competitions. Estimated heritabilities of early life jumping traits ranged between 0.05 and 0.30. Their genetic correlations with adjusted fence height were moderate to high (rg = 0.37–0.63). Relatively more horses that participated in young horse contests competed later on compared to horses that did not participate in young horse contests (p‐value < 0.001). They were also significantly more successful in show jumping competitions. Furthermore, start status in young horse contests was moderately heritable in BWP horses (h2 = 0.56–0.65) and moderately to highly correlated with later success in competitions (rg = 0.30–0.77). Hence, we showed that ELJ traits are good proxies for later success in competitions and that a pre‐selection of horses occurs in young horse contests. It is suggested to stimulate participation to young horse contests to achieve a more representative sample of the population. Early life jumping traits can therefore optimize the genetic progress for show jumping performance. [ABSTRACT FROM AUTHOR]

As the swine industry continues to explore pork quality traits alongside growth, feed efficiency and carcass leanness traits, it becomes imperative to understand their underlying genetic relationships. Due to this increase in the number of desirable traits, animal breeders must also consider methods to efficiently perform direct genetic changes for each trait and evaluate alternative selection indexes with different sets of phenotypic measurements. Principal component analysis (PCA) and genome‐wide association studies (GWAS) can be combined to understand the genetic architecture and biological mechanisms by defining biological types (biotypes) that relate these valuable traits. Therefore, the main objectives of this study were to: (1) estimate genomic‐based genetic parameters; (2) define animal biotypes utilizing PCA; and (3) utilize GWAS to link the biotypes to candidate genes and quantitative trait loci (QTL). The phenotypic dataset included 2583 phenotypic records from female Duroc pigs from a terminal sire line. The pedigree file contained 193,764 animals and the genotype file included 21,309 animals with 35,651 single nucleotide polymorphisms (SNPs). Eight principal components (PCs), accounting for a total of 99.7% of the population variation, were defined for three growth, eight conventional carcass, 10 pork quality and 18 novel carcass traits. The eight biotypes defined from the PCs were found to be related to growth rate, maturity, meat quality and body structure, which were then related to candidate genes. Of the 175 candidate genes found, six of them [LDHA (SSC1), PIK3C3 (SSC6), PRKAG3 (SSC15), VRTN (SSC7), DLST (SSC7) and PAPPA (SSC1)] related to four PCs were found to be associated with previously defined QTL, linking the biotypes with biological processes involved with muscle growth, fat deposition, glycogen levels and skeletal development. Further functional analyses helped to make connections between biotypes, relating them through common KEGG pathways and gene ontology (GO) terms. These findings contribute to a better understanding of the genetic relationships between growth, carcass and meat quality traits in Duroc pigs, enabling breeders to better understand the biological mechanisms underlying the phenotypic expression of these traits. [ABSTRACT FROM AUTHOR]

Qianhua Mutton Merino is a dual-purpose (meat and wool) breed of sheep that has been newly developed in China. In this study, we assessed the growth and development of the Qianhua Mutton Merino sheep breed under house feeding conditions by measuring the body weight and chest circumference of 2300 rams and ewes of this breed aged 0–24 months. Based on the fitting results of three nonlinear growth models, namely Logistic, Gompertz, and von Bertalanffy, in Qianhua Mutton Merino, we selected the von Bertalanffy model because of its highest fitting degree among all models (R2 > 0.977). The significant analysis of the combined fixation of each sheep body's weight and bust took place (A: mature body weight, B: adjustment parameter, K: instant relative growth rate). The results revealed that parameters A, B, and K of body weight and chest circumference have high heritability and thus could be used as target traits for genetic improvement. Moreover, the correlation strength among A, B, and K suggested that these parameters can be used as a reference to adjust the genetic parameters in the growth model to genetically improve the body size of Qianhua Mutton Merino during breeding. [ABSTRACT FROM AUTHOR]