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This investigation was carried out in three winter seasons 2019/20, 2020/21 and 2021/2022at Sakha Agricultural Research Station, Kafr El-Sheikh Governorate, Egypt to estimate some genetic parameters of yield and its components as well as the extent of heterosis, inbreeding depression, heritability, genetic advance, and behavior of gene action in three faba bean crosses. The analysis of gene effects was done using means of Six populations (P1, P2, F1, F2, Bc1 and Bc2) of three faba bean crosses were used in this study. These crosses were (Sakha 3 x R V 322), (Nubaria 1 x RV 322) and (Giza 429 x Marina). Analysis of variance showed significant differences among the generations for all traits. Scaling test showed that most studied characters were significant, indicating the presence of non-allelic interactions. Both dominance and additive gene effects were important but mostly dominance higher than additive ones, indicating that dominant genes playing an important role in the inheritance of such traits beside the additive one. The second cross (Nubaria 1 x RV 322) gave a highly significant (aa) with negative values for flowering, maturity, chocolate spot and rust diseases traits, these indicate that the materials used in this study have a decreasing alleles expression which makes it improving through selection in the early generations. Significant positive inbreeding depression and heterotic effect values were detected for most studied traits. Crosses, especially the first cross (Sakha 3 x R V 322) gave the highest heritability in narrow-sense and genetic advance for number of branches, number of pods/plants, number of seeds/pod and seed yield. Therefore, selection in these populations should be effective and satisfactory in the successful breeding purposes. [ABSTRACT FROM AUTHOR]

This study carried out during two successive seasons 2019 and 2020 at Elbaramun experimental Farm, Horticulture Research Station, Dakahlia, Egypt to select superior genotypes with a good performance in traits of interest from a tomatillo heterogeneous population of the local variety “Balady”. In addition, estimation the genetic gains with the simultaneous selection of yield component traits and soluble solids content. A population derived from “Balady” was used in current study as a basic material. The experimental design used was a randomized complete block design with three replicates. Different vegetative growth and fruit characters were estimated. Results showed that, moderate to high positive genetic gains (ΔG %) were obtained along the evaluated traits ranged from 0.086% to 32.33% for shape index and marketable fruit yield. Regarding earliness traits, genetic gain by selection estimated by 6.862% and 12.97% for early fruit number and early yield, respectively. In addition, the great genetic gain observed was for the marketable fruit yield that recorded 32.33%.Regarding the total soluble solids, a selection gain with 5.616% at 60 old days was obtained after first cycle of selection comparing with the original population. Twenty individuals for each studied trait represent about 8% of selection intensity, showed best values regarding each evaluated trait. The results revealed that the selection for TSS in tomatillo at 45 old days did not gave remarkable gain by selection, (1.538 %) indicating that the selection for this trait would be better at advanced stage of maturity. [ABSTRACT FROM AUTHOR]

This study utilized a dataset comprising 3023 lactation records for Friesian cows, 596 records for Native cows (Baladi), and 1189 records for Crossbred cows spanning from 1994 to 2015. The objective was to estimate and assess genetic and phenotypic parameters and breeding values for 305-day milk yield (305-DMY), lactation period (LP), calving interval (CI), and days open (DO) within the Egyptian dairy context. The motivation for this research stemmed from the need to understand the genetic potential of different cattle genotypes in Egypt and identify opportunities for enhancing dairy production. Data were analyzed using the linear mixed model least squares and maximum likelihood (LSMLMW) and multiple-trait derivative-free restricted maximum likelihood (MTDFREML) programs. The analytical model included fixed effects such as season and year of calving, parity, and genotype groups, while random effects included animal and error. Unadjusted means for 305-DMY, LP, CI, and DO were calculated for each genotype group. Genotype groups significantly impacted all studied traits. Heritability estimates varied across genotype groups, with higher estimates observed in Crossbred (0.32, 0.26, 0.25, 0.23) and Native cows (0.26, 0.28, 0.28) compared to Friesian cows (0.24, 0.22, 0.16, 0.17) for productive and reproductive traits, respectively. Genetic correlations among traits ranged from 0.10 to 0.86 for the three genotype groups, while corresponding phenotypic correlations were generally small to moderate and positive. Regarding breeding values, the accuracy estimates suggested that both sires and cows could contribute to genetic improvement. This indicates the potential for enhancing dairy production through selective breeding strategies., (© 2024. The Author(s).)

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This research was aimed to investigate the production and reproduction traits and their genetic parameters of Egyptian buffaloes under subtropical environment. Heritability, phenotypic, and genetic parameters were estimated for productive and reproduction traits of first parity This study revealed the averages TMY, 305-dMY, LL, BW, DP, SP, CI, and AFC were 2260, 2150 kg, 271 days, 38.63 kg, 210.50 days, 195.20 days, 586.86 days, and 36.61 months, respectively. The heritability estimates for productive traits of the first lactation were 0.61, 0.52, 0.47, 0.20, and 0.23 for TMY, 305-dMY, LL, DP, and BW, respectively. Heritability estimates for reproductive traits SP, CI, and AFC were 0.07, 0.09, and 0.35, respectively. Genetic correlations of most of the investigated first parity traits were positive, with an exception of DP. The genetic correlation was negative between SP and BW, and between AFC and LL. Phenotypic correlations of the first parity among all investigated traits were positive except between DP and TMY, 305-dMY, LL, BW, and AFC. High and moderate heritability estimates indicated that the opportunity of genetic upgrading of these parameters could be achieved owing to sire selection. Selection for high milk yield will be associated with genetic improvement in lactation period and birth weight., (© 2022. The Author(s).)

Genetic parameters and predicting breeding values for some productive traits were estimated using data on 712 Egyptian buffaloes, from 121 sires born between 1990 and 2004, kept at Mehallet Mousa and El -Natafe farms, belonging to Animal Production Research Institute, Ministry of Agriculture, Egypt. Variance components for total milk yield (TMY), lactation period (LP) and body weight of cow at calving (BWC) were estimated by the restricted maximum likelihood method, using multi trait animal model, considering herd- year - season of calving and parity as a fixed effects and individual, permanent and errors as a random effects. Unadjusted means for TMY, LP and BWC were 1591 kg, 203 d, and 479 kg, respectively. Estimates of heritability were 0.115, 0.059 and 0.154 for TMY, LP and BWC, respectively. All genetic and permanent correlations among all traits studied were positive and highly significant (P < 0.01), except the permanent correlations between BWC and each of TMY and LP were negative. Predicted breeding values for TMY, LP and BWC estimated from cows, sire and dams are presented. [ABSTRACT FROM AUTHOR]

• Low direct heritability estimates were reported for pre-weaning mortality in Barki sheep. • A considerable contribution of maternal effects in the genetic variability of the pre-weaning mortality traits. • The birth weight of lamb, year of birth and damage were the most important risk factors affecting the pre-weaning mortality traits. • This information may help breeders to reduce lamb mortality in Barki sheep. Pre-weaning mortality (PM) of lambs is a worldwide economically trait of interest. It has a negative impact on the profitability of sheep farms. However, little is known about the genetic contribution of PM in Egypt and worldwide. In this study, a total of 21,280 records of 5317 Barki lambs descended from 153 rams and 1887 ewes were included. Based on the time of death, 4 binary traits were recorded; D 0 – 3 was animals that were dead immediately or within 72 h after delivery, D 4 – 60 , D 61 – 90 , and D 0 – 90 were lambs that were dead during 4–60 days, 61–90 days after birth and the full period (0–90 days), respectively. The average rate of mortalities for the corresponding traits was 4.6%, 5.4%, 4.3%, 2.2%, and 16.3%, respectively. A logistic regression model with a logit function implemented in R was used to assess the impact of the non-genetic factors on PM in Barki lambs. Bayesian threshold model and Gibbs sampling were used to investigate the genetic parameters and (co)variance components of the studied traits. Results showed that the PM traits were significantly (P < 0.05) influenced by damage, type of birth and birth weight of lamb. Direct heritabilities for PM traits ranged from 0.011 ± 0.01 to 0.02 ± 0.01. Maternal genetic effects for PM traits ranged from 0.13 ± 0.02 to 0.23 ± 0.01. Considerably, maternal effects had a large influence on variance estimates in case of PM trait, but these effects have declined as the lamb age increased. Permanent environmental effects for PM traits ranged from 0.06 ± 0.02 to 0.11 ± 0.02. The genetic correlations between the pairs of studied traits were positively moderate to high and ranged from 0.72 ± 0.07 to 0.95 ± 0.03, which suggested that different genes are contributed to lamb mortality at different ages. Notably, lamb mortality trait was found to be heritable and could be used as important criteria in breeding programs and genetic improvement strategies in Barki sheep. Additionally, improving management practices could also reduce lamb mortality. Results of this study may help animal breeders to reduce lamb mortality in Barki sheep. [ABSTRACT FROM AUTHOR]