Baruah, AnubhaAbedin, Sayed Nabil2023-12-212023-12-212022https://krishikosh.egranth.ac.in/handle/1/5810204107Nanoparticles (NPs), due to their smaller size and unique surface properties can be incorporated into a variety of reproductive biology procedures. The present investigation was carried out from September, 2021 to July, 2022 on four (4) Assam Hill Goat bucks (10 ejaculates per buck) to investigate the effect of supplementing zinc oxide (ZnO) and selenium (Se) NPs in TRIS extender on seminal attributes, lipid peroxidation (LPO) profile, antioxidant enzyme activities viz., superoxide dismutase (SOD), catalase (CAT) and Glutathione-S-transferase (GST), relative heat shock protein (HSP) mRNA levels and fertility of cryopreserved Assam Hill Goat semen. The size morphology and zeta potential values of ZnO and Se NPs were evaluated. Qualified semen samples were divided into five (5) aliquots and then diluted in TRIS extender containing ZnO and Se NP supplementation at different concentrations (T0: control; T1: 0.1mg/mL ZnO NPs; T2: 0.5 mg/mL ZnO NPs; T3: 0.5 μg/mL Se NPs and T4: 1 μg/mL Se NPs). Diluted semen was packed in 0.25 mL straws and then stored in liquid nitrogen. After thawing, post-thaw attributes viz., motility, viability, morphology, plasma membrane integrity (PMI), DNA integrity and mitochondrial membrane potential (MMP) were evaluated. The different treatment groups were also checked for potential NP internalization under transmission electron microscope (TEM). Lastly, straws from the best among the ZnO and Se NP treatments were used for artificial insemination (AI) in does (n=35) synchronized by Ovsynch protocol. Results showed that ZnO and Se NPs were poly-crystalline in nature with particle size below 100 nanometers. The evaluated post-thaw sperm in vitro attributes were significantly (p<0.05) higher in groups containing ZnO and Se NPs supplementation in comparison to control group. Overall, ZnO NPs @ 0.1 mg/mL (T1) had significantly (p<0.05) higher post-thaw sperm in vitro attributes in comparison to Se NPs @ 1 μg/mL. ZnO and Se NP supplementation also significantly (p<0.01) lowered cryocapacitated (B and AR pattern) spermatozoa in comparison to control. The antioxidant enzyme activities (SOD, CAT and GST) were significantly (p<0.001) higher in T1 in comparison to T0. The LPO was significantly (p<0.001) lowered in T1, T2, T3 and T4 in comparison to T0. The leakages of functional enzymes viz., aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) were significantly (p<0.001) lower in T1 in comparison to other groups. Post-thaw sperm motility and MMP had a highly significant(r=0.580, p<0.05) association in T1. SOD (r=0.445) and CAT (r=0.949) had a highly significant (p<0.05) correlation with sperm motility in T1. No internalization of ZnO and Se NPs were observed under TEM. HSP70 and HSP90 mRNA levels were significantly (p<0.001) higher in T1 in comparison to other groups. HSP70 and HSP90 expression levels had a significant (p<0.05) positive correlation with motility in group T1. No significant (p>0.05) differences in pregnancy rates following AI were recorded among the different treatment groups in comparison to control. In conclusion, extender supplemented with 0.1 mg/mL ZnO NPs improved post-thaw semen quality of cryopreserved Assam Hill goat spermatozoa consequently by lowering lipid peroxidation and increasing expression of cryostress associated heat shock genes.EnglishThesis