Key words:Clinical mastitis, Reproductive Performance, Dairy CowsThe objectives of this study were to determine the incidence of clinical mastitis (CM) in relation to some risk factors and its impact on reproductive performance of Holstein cows. Lactation records (n = 1875) were obtained from Dina farms covering the period between 2013 and 2016. One third of cows (647/1875) had contracted at least one episode of CM throughout the entire lactation. Frequency of CM decreased progressively with the month of lactation, and approximately half of the cases occurred within the first three months postpartum. Incidence decreased (P<0.001) with level of milk yield, but increased (P<0.001) with parity. CM significantly (P<0.05) increased calving to first estrus (+ 7.7 days), and to calving first insemination intervals (+6.5 days) compared to non-affected ones. Furthermore, cows contracted CM before conception required 31 days more and +0.47 inseminations to conceive than cows without mastitis. In brief, CM has a negative impact on reproductive performance of Holstein cows, and its occurrence is associated with level of milk yield, lactation order and stage of lactation.

The present study looks for components in seminal plasma (SP) and/or serum that are closely related to in vivo fertility of buffalo bulls. Fourteen healthy mature buffalo bulls were classified according to their in vivo fertility into fertile (n = 10) and subfertile (n = 4) groups. Semen and serum samples were collected from all animals for 12 replicates. The collected ejaculates were examined for sperm characteristics before being centrifuged to collect SP for hormonal (FSH, LH, testosterone, and IGF-1), biochemical [total antioxidant capacity (TAC), catalase (CAT), glutathione peroxidase (GPx), nitric oxide (NO), malondialdehyde (MDA), fructose, total protein, albumin, triglycerides, cholesterol, and high-density lipoprotein (HDL)] and proteomic (SDS-PAGE) analyses. Likewise, serum levels of FSH, LH, testosterone, IGF-1, glucose, total protein, albumin, triglycerides, cholesterol, and HDL were determined. All sperm characteristics and the majority of sperm kinematics were (P &lt; 0.01) different between fertile and subfertile groups. Seminal and serum levels of FSH, LH, testosterone, and IGF-1 were higher (P &lt; 0.01) in the fertile group, but only seminal fructose, total protein, albumin, triglycerides, cholesterol, and HDL were higher (P &lt; 0.01) in the fertile group. Moreover, the fertile group had greater TAC, CAT, GPx, and NO, but the subfertile group had greater MDA. Protein bands of 14, 15, 26, 30, and 55 kDa were larger and denser in the SP of the fertile group but were smaller and faint to absent in that of the subfertile group. Also, the protein fractions of detected protein bands demonstrated a substantial influence of fertility on those of 16, 26, 30, and 55 kDa. In conclusion, sperm characteristics and kinematics with serum, and/or seminal hormonal and biochemical components, should be evaluated for reliable prediction of buffalo bull fertility. Furthermore, protein bands of 26, 30, and 55 kDa may represent fertility-associated proteins in buffalo bull SP.

Single Nucleotide polymorphism (SNP) techniques were used to study the associate polymorphism in exon 1 of growth hormone receptor (GHR) gene and marketing body weights in three rabbit breeds; New Zealand White rabbit breed (pure breed), V-line (Hybrid breeds from New Zealand and California rabbit), and Alexandria breed (Hybrid from V-Line and black Egyptian Baladi rabbit). DNA from blood samples of each kit of the three rabbit breeds were extracted to amplify 263-bp of the gene encoding GHR1. The purified PCR products were sequenced in those had the highest and lowest body weight in each breed. Sixteen new SNPs were detected in GHR1 gene in New Zealand rabbits. In V-line rabbits, three SNPs were detected. Also two SNPs were found in Alex. breed. All these SNPs were related to high body weight as they were reported in higher body weights in the three breeds, and were non synonymous, which led to amino acids substitution. Restriction analysis of PCR product using MSP1 do not produce restriction fragments. Statistically, the results indicated that there were significant correlation between growth performance and GHR1 gene polymorphisms. The results were effective in selection for rabbits that have high growth performance (marker assisted selection). Also, the analysis of this study confirmed that GHR1 gene could be a candidate gene for application in marker assisted selection (MAS) in rabbits.

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Animal feeding research has revealed a close relationship between the chemical composition and nutritional value of cow rations, the number of rumen bacterial communities and animal productivity. Our present research aimed to investigate the outcome of inclusion of different levels of protein concentrate in rations of Ayrshire dairy cows in relation to the rumen microbiome, reproductive traits and economic value. Forty-five Ayrshire cows were divided into three groups (15 in each). The first control group 0 AM was fed the basal ration, while the second 1 AM and third 2 AM groups were fed the basic ration with the sunflower cake replaced by different levels of protein concentrate Agro-Matic (1 and 1.5 kg/head/day, respectively). Ruminal fluid samples, reproductive parameters and economic value were studied. During the early lactation period, 120 days in milk (DIM), the number of pathogenic microorganisms decreased in both the 1 AM and 2 AM groups when compared with the control group 0 AM; moreover, a significant decrease in Peptococcus bacteria was recorded in the 1 AM group, while Fusobacterium decreased in the 2 AM group. At the end of lactation, the total number of cellulolytic bacteria increased with the use of protein concentrate in animals of the 1 AM group when compared with the control group. Regarding undesirable bacteria, the 2 AM group recorded the highest value for Lactobacilli and Actinobacteria when compared with the 0 AM group (0.18 and 8.90 vs. 0.04 and 4.24), and the differences were significant (p < 0.05). The insemination index and the duration of the days open period decreased in the 2 AM group, while the differences were p > 0.05. The profitability of milk production increased by 2.76% and 6.28% in both supplemented groups, and the differences compared to the 0 AM group were significant. We conclude that the supplementation of Agro-Matic caused no deviations from the normal standards of cellulolytic, amylolytic, transit and pathogenic bacteria, no impact on reproductive functions and significantly improved the profitability of the milk production process of Ayrshire dairy cows.