For assessing the genetic diversity and genetic characterization of five Egyptian buffalo populations a total of 12 microsatellite markers were used. The total number of buffaloes sampled was 80, collected at random from five farms in five different governorates; Cairo, Kafr El-Sheikh, Shebeen El-Kom, Menoufia, and Beni Suef. The genetic parameters (allelic diversity, allelic frequencies, observed heterozygosity, unbiased expected heterozygosity, and polymorphic information content) were calculated using three different programs. All used microsatellites were polymorphic and ranged from four alleles (Loci; CSSM029, CSSM036, CSSM038, CSSM043, CSSM046, and ILSTS005) to nine alleles (Loci; BM1818 and CSSM047) with a total of 64 alleles in the whole population. Allelic richness for the whole population ranged between 3.297 (in locus CSSM029) and 6.806 (in locus CSSM047) with overall mean 4.574. Within populations, Kafr El-Sheikh population had the highest average of allelic richness (4.384). This indicates the potential of this population to adapt with environmental changes in future compared with other populations. BMC1013, BM1818, CSSM019, and CSSM047 showed the highest allelic richness. PIC estimates were high and ranged between 0.65 (in locus CSSM029) and 0.92 (in locus CSSM022) with an average of 0.82. Values of H o were lower than values of H Nb for all populations, which denoting depression of heterozygotes in these populations and may be attributable to existence of null alleles and inbreeding. This study as well proves the usefulness of heterologous bovine microsatellite markers in evaluation of the genetic variability in Egyptian buffalo populations due to high polymorphism, informativeness of these markers which can be used to develop future breeding strategies and conservation decisions on our indigenous breed.

The present study aimed to estimate the genetic parameters of first lactation milk yield (FLMY), first lactation period (FLP), first dry period (FDP) and first calving interval (FCI) and inclusion these studied traits in selection indices through different animal models. The data utilized in this study were obtained from 1821 normal first lactation of Friesian cows belong to Sakha and EI-Karada Experimental stations of Animal Production Research Institute (APRI), Dokki, Cairo, Egypt. Data were collected during the period from 1990 to 2016 and analyzed using the MTDFREML program. Covariance components were used to construct the different selection indices for FLMY kg, FLP day, FDP day and FCI day with four multiple animal models. Means for FLMY, FLP, FDP and FCI were 2425 kg, 304 d, 170 d and 474 d, respectively. Direct heritability (h 2 a) for the above-mentioned traits were 0.32, 0.29, 0.27 and 0.18, respectively. The corresponding estimates of the maternal heritability (h 2 m) for the same traits were 0.25, 0.22, 0.30 and 0.27, successively. Estimates of direct genetic correlations among studied traits ranged from -0.52 to 0.61. The phenotypic correlations among investigated traits were ranging from -0.20 to 0.23. Animal model number two that included the additive and permanent effects had the highest accuracy. On the contrary, model number three that included additive and maternal effects. The ranking correlations among four animal models were higher than 0.93. This indicates that using one of the studied models can be achieved the genetic improvement. We would however recommend that included the permanent environmental effects on analytical models when selection for these traits in Friesian cows under Egyptian condition.

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To detect the linkage between single markers of microsatellite type and mastitis incidence in Egyptian buffalo three markers (BM1258, BM1443 and BM1818) and one hundred twenty-three lactating animals were used. The selected animals were tested using Modified White Side Test (MWT) to screen animals for mastitis. Non-denatured polyacrylamide gel was used to determine the sizes of the PCR amplified products using reference animal to verify the allelic sizes obtained. For each marker, the frequencies of alleles and genotypes for both positive and negative animal groups were compared by using the chi-square test and the Fisher's exact test. The odds ratios calculated as an estimate of relative risk of mastitis incidence associated with each microsatellite genotypes. A positive mastitis test reaction (MWT) was revealed in 19.5% of total samples. For BM1258, BM1443, and BM1818, the number of alleles was found to be 4, 3 and 5, respectively. The polymorphism in all three studied loci was high (PIC>0.5). The genetic parameters of these loci, including observed and expected heterozygosity, were estimated using full characterizations of this set of three polymorphic loci. The polymorphic information content, heterozygosity, and number of successful alleles of the studied loci showed that BM1443 had the lowest variability and BM1818 had the highest variability, with 0.597 and 0.757, respectively. The overall effects of the three studied markers on mastitis incidence were significantly (P<0.05) different. The genotypes combination '72/79 ', '74/74', and '79/82' at BM1258 loci; '78/78' and '88/88' at BM1443 loci, were observed only in the mastitis free animals. On the other hand, BM4505 loci genotypes were found in the positive populations except the combination of genotypes 134/134, 134/140 and 134/144 animals. The information observed in the present study, could be valuable for improving mastitis resistance in Egyptian buffalo breeds through using molecular tools.

The aims of the current study were to estimate the effect of inbreeding and genetic parameters of birth weight (BW), preweaning daily gain (PDG) and weaning weight (WW) in buffalo calves. Data were collected from weight records of buffalo calves raised at Mahallet Mousa Farms belonging to the Animal Production Research Institute. It included 2015 progeny of 125 sires, through 17 consecutive years. Effect of inbreeding was highly significant for all studied traits. The overall average of inbreeding coefficient was 0.53% in whole population and 15% in the inbred animals. The means of BW, PDG and WW in non-inbred group were 37.318, 0.490 and 88.86 Kg, respectively. While, the means of the same traits in inbred group were 31.96, 0.446 and 78.82 Kg, respectively. Corresponding the inbreeding depression as overall means of levels for above traits were -0.350, -0.003 and -0.716, respectively. Direct heritability (h 2 a ) in inbred animals for BW, PDG and WW were 0.28, 0.25 and 0.19, respectively. On the other hand, the h 2 a of studied traits in non-inbred animals were 0.32, 0.30 and 0.23, respectively. The maternal heritability (h 2 m ) for mentioned traits were 0.25, 0.26 and 0.21 within inbred animals and 0.29, 0.28 and 0.22 within non-inbred animals, respectively. Likewise, the genetic correlations (r g ) among studied traits were ranged from (0.12 to 0.56) in inbred animals and were ranged from (0.16 to 0.63) in non-bred animals. As well the phenotypic correlation (r p ) among studied traits were ranged from (0.04 to 0.50) for inbreds and were varied between (0.04 and 0.54) for non-inbreds. The inbreeding was pronounced detrimental effects of studied traits in buffalo calves. Therefore, breeding strategies should be develop for reduce the inbreeding effects and inclusion the effects of inbreeding in genetic evaluation programs in Egyptian buffalo calves.