| Dissertation note |
This project was executed to improve the semen quality during freezing process and to improve subsequent fertility rate in Nili-Ravi buffaloes with hormones (PGF2a and oxytocin) supplementation. Pooled semen from Nih Ravi buffalo bulls (n2) was divided into 8 equal parts after complete evaluation and subjected to the hormonal treatments. PGF2a (Lutalyse®) @ 2.5mg, 5.0mg and 7.5mg and oxytocin (Cintocinon®) @ 2.5 I.U, 5.0 I.U and 7.5 I.U/lOOml of diluted semen were added. One group (-ye control) received indomethacin @ 20mg + PGF2a @ 5.Omg/lOOmi of diluted semen. One group remained without any treatment (+ve control). Semen was cooled, filled in 0.5ml straws, equilibrated at 4°C for 4 h ours and frozen i n liquid nitrogen. After 24 hours of deep freezing, semen was thawed and evaluated for percentage motility of spermatozoa, plasma membrane integrity (HOS assay), acrosome integrity (NAR), viability (Live/Dead), longevity (hours) and fertility. Four (4) straws from each treatment group were thawed and pooled in 5m1 cuvette in water bath at 37°C and evaluated for quality parameters. Twenty five (25) straws from each treatment group were used to inseminate the buffaloes in standing estrus at 3 A.I centers (Phool nagar, Changa manga and Kot radlia kishen) in district Kasur. Pregnancy was checked 60 days post insemination. Data collected was presented as mean ± SEM, treatment groups were compared using ANOVA, unpaired two sample test and Pearson correlation at 5% level of confidence interval using Minitab® computer software. Results o f this study revealed that addition of both Lutalyse® (PGF2a) and Cintocinon® (oxytocin) did not show significant (P>0.05) improvement in any quality parameters measured and a non significant correlation was observed between treated groups and control except indomethacin and viability of spermatozoa where a significant negative correlati9n (r = -0.980) was found. However, blocking of seminal prostaglandins with indomethacin shows significant (P<0.05) deterioration in percentage motility, plasma membrane integrity, viability and longevity of spermatozoa but acrosome integrity remain unchanged. Results of fertility trial showed significant difference (P<0.5) among treatment groups. In conclusion, we can say that although hormonal addition did not improve semen quality but improve fertility rate, therefore, the importance of prostaglandins in semen can not be neglected. The W nature and physiological amount in buffalo semen should be investigated and maintained by exogenous addition after dilution during processing to maintain post thaw semen quality and fertility. However, it is suggested that pure forms of hormones should be used to add in semen instead of Lutalyse® as it contains 1.56% alcohol which is supposed to be detrimental to spermatozoa.
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