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ABSTRACT The present study aimed to evaluate the growth of Criollo foals from birth to 800 days of age using Brody, Gompertz, Logistic, and Von Bertalanffy nonlinear models. The data utilized consisted of weight, height, chest circumference, and shin circumference taken from 75 foals kept in southern Brazil. Morphometric traits analyzed showed mean values ranging from 63 to 325 kg for weight, 0.92 to 1.32 m for height, 0.88 to 1.58 m for chest circumference, and 0.12 to 0.18 m for shin circumference. For the evaluated traits, all applied nonlinear models achieved convergence. The results indicated that the Brody model provided the best adjustments for weight, height, and chest circumference. Gompertz model was found to be the most suitable for describing the growth curve of shin circumference. The animals exhibited an increase in weight during the evaluated period. Height showed the most rapid increase until approximately 365 days of age, followed by a decrease, and a more homogeneous growth pattern thereafter. Chest circumference exhibited more uniform growth in animals from 365 days of age onwards, with slower growth and greater variability observed from 400 days of age. Shin circumference showed greater growth in the first months of age, remaining stable thereafter. We observed that 94 and 5% of the animals in the studied population did not meet the minimum values for height and chest circumference, respectively, according to the breed standards from 24 months of age. Our results can assist in selection and future studies with the Criollo breed.

Resumo Este estudo teve como objetivo avaliar o desempenho de métodos para estimativa da evapotranspiração de referência (ETo) nas escalas diária e decendial em sete municípios do Rio Grande do Sul. Foram utilizados dados meteorológicos diários de janeiro de 2015 a dezembro de 2020, para estimar a ETo por Penman-Monteith como padrão e para 32 métodos a serem avaliados com o uso de seis indicadores (índices de confiança e de concordância, coeficientes de correlação e de determinação, erro quadrático médio e erro médio). Os métodos baseados na radiação de Ritchie, Stephens-Stew, Souza-Silva, Valiantzas-3 e Hargreaves são indicados em todos os municípios para estimar a ETo diária e decendial. Baseado no índice de confiança, todos tiveram um ‘ótimo’ desempenho e apresentaram uma variação na estimativa inferior a 1 mm e tendência em subestimar a ETo. Na ausência de dados de radiação, há possibilidade de estimar a ETo diária usando alguns métodos baseados na temperatura do ar, como o de Romanenko, apenas para o município de Bagé. Na escala decendial, pode-se recorrer ao método aerodinâmico de Brockamp, nos municípios de Bagé e do Rio Grande e nos métodos fundamentados na temperatura de Hargreaves-Samani 1 e 2 e de Baier-Rob em todos os municípios, exceto de Santa Rosa.

ABSTRACT: In beef cattle breeding programs, various selection criteria have been proposed and employed with the aim of improving traits related to carcass composition and the quality of the final product, meat. However, the importance of genotype by environment interaction (G×E) for such traits is still not well understood. Our objectives were: 1) to investigate the importance of G×E on ultrasound carcass traits, growth and visual scores and 2) to estimate the genetic correlation of ultrasound carcass traits with growth and visual scores taking into account the G×E in Hereford and Braford cattle. A multiple-trait reaction norm model was fitted to the field records of 37,948 animals. With the exception of postweaning average daily weight gain (ADG), the G×E can lead to important changes in the ranking of estimated breeding values of sires across environments for all traits. Thus, models that consider heterogeneity of genetic variances along an environmental gradient may be considered more appropriate for genetic evaluations of animals reared under conditions similar to the present study. Based on estimates of genetic correlation, the quality of visual scores or ADG as indicators of carcass quality assessed by ultrasonography is dependent on the production environment.

ABSTRACT Data from 83,088 Hereford and Braford cattle were used to compare parameters and breeding values obtained using linear and threshold models for visual scores of limb conformation (LCW and LCY), breed traits (BTW and BTY), sexual traits (STW and STY), eye pigmentation (EPW and EPY), and navel size (NSW and NSY) at weaning and yearling, respectively. Additionally, principal component analysis was applied to investigate the relationship among the estimated breeding values. Higher direct heritability were estimated using the threshold model (ranging from 0.134±0.021 to 0.194±0.023) compared with the linear model (ranging from 0.085±0.008 to 0.120±0.009). Rank correlations between breeding values predicted using linear and threshold models ranged from 0.61 to 0.88 (LCW), 0.53 to 0.91 (BTW), 0.66 to 0.87 (STW), 0.80 to 0.96 (EPW), 0.87 to 0.95 (NSW), 0.70 to 0.92 (LCY), 0.49 to 0.93 (BTY), 0.56 to 0.95 (STY), 0.88 to 0.97 (EPY), and 0.80 to 0.95 (NSY). The low genetic variability of the studied traits suggests a small genetic gain in the morphology and adaptation. According to the results obtained in the rank correlation, the percentage of coincident animals and the cross-validation analyses, it is recommended to use the threshold model for limb conformation, breed, and sexual traits. For eye pigmentation and navel size scores, both models can be used. In practical terms, the producer will be able to carry out his own selection, considering other traits that are not currently incorporated in the selection indexes, but that can lead to simultaneous gains in the morphology and adaptation of Hereford and Braford cattle.

In beef cattle, the selection for higher weights at young ages has been questioned with the argument that this criterion may increase the adult weight of cows, resulting in higher costs. Therefore, selection criteria should be employed to increase weights at young ages with minimal impact on the adult weight of cows. Additionally, the relationship between measures of cow production efficiency and other well-established selection criteria in breeding programs remains poorly understood. The objective of this study was to longitudinally evaluate the relationship between the weaning index (WIndex) as a measure of efficiency and growth traits of the cows. Possible changes over time in WIndex due to selection applied for yearling weight (YW) were also investigated. The WIndex was proposed to maximize genetic response in the weaning weight of the calf while maintaining genetic gain in BW of the cow at zero. A random regression model was adopted to estimate correlations between WIndex, BW, hip height (HH), and body condition score (BCS) using records of Nelore cows from three lines. Genetic trends were calculated for the control line (NeC) and lines selected for greater YW (NeS and NeT). The age of 3 years was the most critical for the weaning efficiency of the cows. At this stage, young cows are still growing and wean lighter calves than their adult counterparts. The genetic correlation estimates between WIndex and BW (−0.58 to 0.04), HH (−0.05 to −0.34), and BCS (−0.51 to −0.17) were close to zero or negative. BW and HH were strongly correlated genetically across all ages (0.73–0.76). In general, HH exhibited a weak and negative genetic relationship with BCS. The genetic correlation between BW and BCS was stronger for advanced ages (0.45–0.68). In lines selected for YW, important increases in WIndex were observed. However, NeS has been selected since the 1980s until the present for YW, and thus, it showed a more pronounced trend of increasing BW and, consequently, a more modest trend of increasing WIndex compared to NeT. In contrast, WIndex exhibited a trend close to zero for NeC. In this context, monitoring HH and BCS can be useful to avoid losses in the weaning efficiency of cows. Furthermore, we suggest that one way to mitigate efficiency losses in calf production could involve stabilizing the BW of cows and increasing the weaning weight of calves using the WIndex.

This study utilized Bayesian inference in a genome‐wide association study (GWAS) to identify genetic markers associated with traits relevant to the adaptation of Hereford and Braford cattle breeds. We focused on eye pigmentation (EP), weaning hair coat (WHC), yearling hair coat (YHC), and breeding standard (BS). Our dataset comprised 126,290 animals in the pedigree. Out of these, 233 sires were genotyped using high‐density (HD) chips, and 3750 animals with medium‐density (50 K) single‐nucleotide polymorphism (SNP) chips. Employing the Bayes B method with a prior probability of π = 0.99, we identified and tagged single nucleotide polymorphisms (Tag SNPs), ranging from 18 to 117 SNPs depending on the trait. These Tag SNPs facilitated the construction of reduced SNP panels. We then evaluated the predictive accuracy of these panels in comparison to traditional medium‐density SNP chips. The accuracy of genomic predictions using these reduced panels varied significantly depending on the clustering method, ranging from 0.13 to 0.65. Additionally, we conducted functional enrichment analysis that found genes associated with the most informative SNP markers in the current study, thereby providing biological insights into the genomic basis of these traits. [ABSTRACT FROM AUTHOR]

Palm oil is the world's second most consumed vegetable oil, sourced from the tropical palm tree Elaeis guineensis. Its consumption has been associated with a higher incidence of cardiovascular disease, largely due to its elevated palmitic acid content, however those studies are contradictory and inconclusive. Wishing to contribute to this issue, the present study aims to investigate the molecular and toxicological effects of this oil and the involvement of oxidative stress, given its role in metabolic dysfunctions using Drosophila melanogaster. This study examines survival rates, and locomotor performance, oxidative status by analysis of lipid peroxidation, ROS formation, thiol levels and antioxidant enzyme activity, and metabolic parameters such as cholesterol and triglycerides, glucose, trehalose and glycogen levels. Exposure to palm oil concentrations of 10% and 30% resulted in a shortened lifespan, reduced locomotor performance, and increased lipid peroxidation, with lower thiol levels and antioxidant enzyme modulation. Cholesterol levels was increased whereas energetic fuels as glucose and glycogen and trehalose were decreased mainly after 10 days of exposure. These findings underscore the detrimental effects of high‐fat diets containing palm oil on lifespan, antioxidant defenses, and metabolism in Drosophila melanogaster. This data highlights the potential risk associated with the habitual consumption of palm oil in the daily diet by population, particularly concerning cardiovascular health and metabolic function. Summary: This manuscript explores the impact of consuming commercial palm oil on the diet of Drosophila Melanogaster, a reliable model for studying diet effects on metabolism, behavior, and biochemistry. Despite being a natural substitute for trans fats, the widespread incorporation of palm oil into diets raises concerns. Despite its natural origin, palm oil has been shown to affect behavior, reduce metabolic activity, and elevate cholesterol levels, alongside inducing oxidative stress, linked to various pathologies. Therefore, individuals should be cautious about excessive palm oil consumption, as it may contribute to cardiovascular and neurological conditions, despite its natural sourcing. [ABSTRACT FROM AUTHOR]

The growth of Nelore cattle was analysed considering the following performance parameters; the effect of the calving order of cows on the phenotypic expression of birth weight (BW), average daily gain from birth to weaning (BWG), and weaning weight (WW), the estimated genetic parameters for the traits, including the covariance components between direct and maternal genetic effects. Genetic trends and correlated responses were also obtained for the studied traits. The calving order of cows, as well as other fixed effects used to obtain the adjusted phenotypic means, were statistically significant (p < 0.001) for studied traits. Direct heritability was estimated at 0.24 ± 0.01 (BW), 0.15 ± 0.01 (BWG), and 0.18 ± 0.01 (WW), while maternal heritability was 0.06 ± 0.01 (BW), 0.12 ± 0.01 (BWG), and 0.11 ± 0.01 (WW). The correlations between direct and maternal effects within the same trait were negligible. Moderate to higher direct genetic correlations (ranging from 0.54 ± 0.04 to 0.98 ± 0.01) and maternal genetic correlations (ranging from 0.34 ± 0.09 to 0.99 ± 0.002) were estimated between the studied traits. Unlike direct genetic effects, there was no significant change in maternal genetic effects over time (p > 0.05). These results indicated the need for revising selection indexes for enhancing maternal ability. Correlated responses were generally lower compared to direct responses, except for BWG. The selection for BWG, considering the maternal genetic effect, would be more efficient to improve maternal ability of the cows for pre-weaning growth in relation to selection for WW. Our results found that direct genetic merit improves pre-weaning weight and this trait can be incorporated into the breeding goal as reflected in the WW. [ABSTRACT FROM AUTHOR]

Context. The knowledge of the genetic variability of gestation length and its correlations with other traits is relevant for selection decisions in beef cattle. Aims. Genetic parameters and trends were estimated for gestation length (first (GL1), repeated measures range of 1--6 (GL)) and traits currently used as selection criteria (birth weight (BW), weight gain from birth to weaning (BWG), weight gain from weaning to yearling (WYG), scrotal circumference (SC), score of conformation (YC), score of precocity (YP), and score of muscling (YM)) in Brazilian Angus cattle. In addition, direct and correlated selection responses were predicted. Methods. A series of single- and two-trait Bayesian analyses were performed on beef cattle data from14 farms across different regions of Brazil, by using linear and threshold animal models. Key results. A moderate heritability was estimated for GL1 (0.356 ± 0.058); however, the estimate for GL was low (0.189 ± 0.028) as was that for repeatability (0.204 ± 0.027). Lower accuracies of breeding values were obtained for GL than for GL1, ranging from0.490 ± 0.161 to 0.687 ± 0.037. Direct heritability estimates for growth and body composition traits were low, except for SC and BWG (0.301 ± 0.060 and 0.241 ± 0.019 respectively). Genetic correlations of 0.558 ± 0.121 and 0.739 ± 0.131 were estimated between GL1 and BW, and between GL and BW respectively. The other traits studied were estimated to have weak or nearzero genetic correlations with gestation length traits. Positive and moderate genetic associations were estimated between BW and BWG, SC, and visual scores (ranging from 0.338 ± 0.095 to 0.458 ± 0.092), but a near-zero estimate was obtained with WYG (0.127 ± 0.150). Weight gains were more highly genetically correlated with visual scores than between themselves (BWG and WYG) and with SC. The SC was highly genetically correlated with visual scores (0.684 ± 0.054 to 0.714 ± 0.050). Genetic trends showed that all traits studied have been changing in a positive direction, being unfavourable for BW and GL. Higher genetic gains were expected from using direct selection than from using indirect selection for GL1. Conclusions. Rapid growth is genetically associated with superior conformation, precocity and musculature, as well as a large scrotal circumference in males. However, selection decisions that heavily focus on these traits are likely to lead to more calving difficulties in the longer term. Implications. Selection indices should incorporate traits that measure calving difficulty directly if relevant records are available. Currently, considering its practical implications in primiparous anoestrus, the first-gestation length could serve as a viable alternative for inclusion in selection indices. Due to the low repeatability of the gestation length, decisions to cull on the basis of only one or two records of GL are highly inaccurate. [ABSTRACT FROM AUTHOR]

Research results reporting the effect of under periods of induced salt stress on biomass production, yield and composition of the essential oil of rosemary are scarce. The aim of this study was to evaluate phytomass production and essential oil yield of basil plants (Ocimum basilicum L. 'Basilicão') in soilless cultivation under different levels of salt stress, in addition to analyzing their phytochemistry. Four periods of salt stress were evaluated in summer and winter experiments: 0, 10, 20 and 30 days. The analyzed variables were fresh mass (FM), dry mass (DM), number of inflorescences (NI), essential oil yield (EOY), and phytochemistry. A completely randomized design was used, and the data were submitted to analysis of variance and evaluated by polynomial regression. Salt stress reduces leaf and stem FM and DM and the FM of total aerial part, in summer and in winter; it increases FM, DM, and NI in summer; there is no difference in FM, DM or NI in winter; and no difference in DM of total aerial part in both seasons. Leaf EOY reduces under salt stress during both seasons, as well as total EOY in winter. Inflorescence EOY increases in summer. Linalool, the main component of the oil, increases under salt stress. [ABSTRACT FROM AUTHOR]

• Selection for higher yearling weight impacts cow-calf efficiency. • Genetic trends reflect the correlated effects on cow and calf traits. • Monitoring cow hip height and body condition avoids efficiency losses. • WIndex optimizes calf weaning weight while stabilizing the cow's mature weight. • Proposed strategies mitigate calf production losses from weight-focused selection. In beef cattle, the selection for higher weights at young ages has been questioned with the argument that this criterion may increase the adult weight of cows, resulting in higher costs. Therefore, selection criteria should be employed to increase weights at young ages with minimal impact on the adult weight of cows. Additionally, the relationship between measures of cow production efficiency and other well-established selection criteria in breeding programs remains poorly understood. The objective of this study was to longitudinally evaluate the relationship between the weaning index (WIndex) as a measure of efficiency and growth traits of the cows. Possible changes over time in WIndex due to selection applied for yearling weight (YW) were also investigated. The WIndex was proposed to maximize genetic response in the weaning weight of the calf while maintaining genetic gain in BW of the cow at zero. A random regression model was adopted to estimate correlations between WIndex, BW, hip height (HH), and body condition score (BCS) using records of Nelore cows from three lines. Genetic trends were calculated for the control line (NeC) and lines selected for greater YW (NeS and NeT). The age of 3 years was the most critical for the weaning efficiency of the cows. At this stage, young cows are still growing and wean lighter calves than their adult counterparts. The genetic correlation estimates between WIndex and BW (−0.58 to 0.04), HH (−0.05 to −0.34), and BCS (−0.51 to −0.17) were close to zero or negative. BW and HH were strongly correlated genetically across all ages (0.73–0.76). In general, HH exhibited a weak and negative genetic relationship with BCS. The genetic correlation between BW and BCS was stronger for advanced ages (0.45–0.68). In lines selected for YW, important increases in WIndex were observed. However, NeS has been selected since the 1980s until the present for YW, and thus, it showed a more pronounced trend of increasing BW and, consequently, a more modest trend of increasing WIndex compared to NeT. In contrast, WIndex exhibited a trend close to zero for NeC. In this context, monitoring HH and BCS can be useful to avoid losses in the weaning efficiency of cows. Furthermore, we suggest that one way to mitigate efficiency losses in calf production could involve stabilizing the BW of cows and increasing the weaning weight of calves using the WIndex. [ABSTRACT FROM AUTHOR]