No abstract

Background: Addition of the antioxidant to extender media is the most appropriate attempt to reduce structural losses encounter during the process of cryopreservation. Hence semen excellence could be maintained for longer duration without adverse impact. Additionally antioxidants are not only capturing the reactive oxygen species but also improve the sperm quality indicators and fertility. Accordingly, current elucidation has been executed to explore the dose depended appraisal of varied concentration of α-tocopherol in Tris-based extender on frozen-thawed bull semen quality parameters for enhancement of bull semen cryopreservation in the subtropical ecosystem of Peshawar. Materials, Methods & Results:Experiments were carried out on semen that has been collected from both Achai-an indigenous breed and Holstein Friesian (HF) -the exotic breed in artificial vagina maintained at 42°C from the experimental bulls of either breed and processed independently breed wise. Semen specimens with above 70% motility were evaluated separately breed-wise under same environmental condition. Standard procedure was adopted to extend the collected semen in the experimental extenders and frozen subsequently. After thawing, further Analysis of the frozen straws of semen was carried out for sperm excellence indicators that include motility, viability, acrosomal integrity and functional integrity of spermatozoa under the subtropical condition. Sperm viability and acrosomal integrity were determined by dual staining procedure i.e. Trypan-blue and Giemsa stains. The hypo-osmotic swelling (HOS) test was used to assess plasma membrane integrity. The current elucidation demonstrated that α-tocopherol 1.5 mg/mL supplemented in extender had significantly (P < 0.05) increased sperm excellence gauge that includes motility, viability, acrosomal integrity and functional membrane integrity in both the breeds. On the other hand, the result further elucidated those concentrations higher or lower than 1.5 -1 mg/mL α-tocopherol supplemented in the present study resulted in a lower semen functional attributes subsequent to freezing. Discussion: Biological samples were preserved by various methods such cryopreservation at low temperature to maintain them intact and facilitate downstream experiments. Antioxidants were associated with the chemical breakage of the substrate consequential from oxidation and counterbalance the free radicals thus diminish the damaging impacts to spermatozoa in cryopreservation. There is lack of data with respect to lipid peroxidation and cell reinforcement limit in cryopreserved semen, and cryopreservation is related with the generation of receptive oxygen species (ROS) which lead to lipid peroxidation (LPO) of sperm membranes, bringing about lost motility, viability and fertility of sperm. Recently, in the reproductive management of the dairy animals, an important focus of research is to overcome the deleterious impact associated with semen cryopreservation. Elucidation of differential dose depended expression of α-tocopherol...

No abstract

The present study was designed to investigate the effects of single nucleotide polymorphisms (SNPs) in the JAK2 gene on the production and mastitis related traits in dairy cattle. Blood and milk samples were collected from 201 lactating dairy cattle of three breeds, i.e. Holstein Friesian (HF), Jersey (J) and Achai (A) and their crosses maintained at well-established dairy farms in Khyber Pakhtunkhwa, Pakistan. Generalized linear model was used to evaluate the association between genotypes and the studied traits. A DNA pool was made from randomly selected 30 samples which revealed three SNPs, i.e. SNP 1 in 5’ upstream region (G>A, rs379754157), SNP 2 in intron 15 (A>G, rs134192265), and SNP 3 in exon 20 (A>G, rs110298451) that were further validated in the population under study using SNaPshot technique. Of the three SNPs, SNP 1 did not obey Hardy-Weinberg equilibrium (P<0.05). SNP 2 and SNP 3 were found to be in strong linkage disequilibrium and allele G was highly prevalent compared to allele A in these SNPs. in SNP 1, the GG genotype was associated with significantly (P<0.01) higher SCC, whereas SNP 2 and SNP 3 were significantly (P<0.01) associated with higher lactose percentage compared to the other geno-types. The haplogroups association analysis revealed that H1H2 (GG GG AG) has significantly lower SCC than H2H2 (GG GG GG). The results infer that JAK2 could be an important candidate gene and the studied SNPs might be useful genetic markers for production and mastitis related traits.

No abstract