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Abstract Background There are no studies belong NOTCH2 gene polymorphism in relation to reproductive and productive traits in Holstein cattle. The objective of the present study was to investigate the effect of NOTCH2 gene polymorphisms on productive and reproductive performance of fertile and anestrum cattle. Methods The cattle were classified into anestrus for 3–12 months postpartum (n = 115, 37.7%) and normal cyclic fertile (n = 190, 62.3%). Age at 1st calving, calving interval, calf birth weight, milk yield and days of milking data were obtained from the farm records for all animals. Blood samples were collected from fertile and anestrum animals for DNA extraction and the PCR as well as single-strand conformation polymorphism techniques (SSCP) were performed for detection of the NOTCH2 gene polymorphism. Results The sequencing results showed that NOTCH2 gene in cattle is polymorphic with 5 genotypes AA, AG, GG, CC and CT. Four novel SNPs as transition single base substitution mutations were detected at 3: 23,192,033 (A/G), 3:23192149 (C/T), 3:23192071 (C/T) and 3:23192143 (G/A). GG genotype of NOTCH2 gene was associated with shorter calving interval and heavier calf birth weight in both fertile and anestrum cattle. Conclusions NOTCH2 gene in cattle could be used as a genetic marker involved in reproductive traits in both fertile and anestrum cattle.

Abstract Background Vancomycin-resistant enterococci (VRE) are among the most common causative pathogens for nosocomial infections worldwide. Moreover, strains of VRE have been isolated from several domestic livestock in Egypt. Methods This study examined if healthy dogs are a potential source of VRE infection by isolating and characterizing Enterococcus faecium strains from stool samples on a morphological basis and biochemical activities. Subsequently, it was confirmed by genotypic characterization using polymerase chain reaction (PCR), followed by the detection of antibiotic resistance genes, virulence determinants, and genes contributing to enterocin production by PCR. Furthermore, the phylogenetic relationships among vanB and tetL genes were analyzed. Results All ten fecal samples were identified as E. faecium and confirmed by PCR. In addition, 90% of the isolates tested were positive for the virulence genes gelE and esp, and all the isolates tested were positive for the antibiotic resistance genes tetL and vanB. Only three of the five enterocin genes examined were detected. Ent As-48, bacteriocin 31, and Ent L50 were identified in 100%, 80%, and 60% of the samples, respectively. Conclusion Dogs should be regarded as a reservoir of E. faecium that carries vancomycin resistance and virulence determinants that may affect public health in Egypt, considering a "One Health" task force approach to restrict their spread.

Fresh semen from fifty bulls was evaluated for ejaculate volume, individual motility, concentration, lives sperm and abnormalities as well as acrosome integrity. Bulls were classified according to semen motility into two groups; good and poor. DNA was extracted from semen of both groups, then the PCR followed by single-strand conformation polymorphism (SSCP) techniques were performed for mutation detection in gonadotropin releasing hormone receptor (GnRHR) gene through multiple sequence alignment. The results showed that the percentages of sperm motility, sperm concentration and live sperm, were significantly higher in good than poor semen quality bulls. However, semen volume, percentage of acrosome integrity and abnormalities did not differ between good and poor. The PCR amplification of 240-bp fragment and the results of SSCP appeared a genetic polymorphism with two patterns. Pattern I was seen in all good bulls, with incidence of 100%. Pattern II appeared only in poor semen quality bulls with a frequency of 31.25%. The sequence analysis of the PCR product for the two patterns showed two single nucleotide polymorphisms (SNPs) as a transversion base substitution mutation at positions 20 (T/A) and 193 (A/T). The GnRHR gene could be used as a genetic marker related to semen quality in buffalo due to the good semen bulls had a unique pattern.