Assessment of the fertilizing potential of frozen bovine spermatozoa by different in vitro techniques

الملخص EN

Thirty two semen ejaculates were diluted either in Tris diluents or egg yolk citrate diluents and frozen in 0.5 ml straws.

The percentage of progressive motile sperm was assessed after dilution, just before freezing after thawing and during 3 h of incubation period at 37°C and viability index was calculated.

The integrity of sperm plasma and acrosomal membranes was assessed immediately after thawing by using different techniques (% of abnormal acrosome, % of serum induced head to head agglutination, the hypo osmotic swelling test, invitro induction of acrosome reaction, determination of aspartate aminotransferase (AST) and Malonaldehyde (MAL) in seminal plasma.

The objective of this study was to combine these tests in order to provide information about the integrity of the whole sperm surface, as well as acrosome status.

The results revealed that the percentage of acrosomal abnormalities was 15.75 and 11.19 in egg yolk citrate and Tris diluted semen samples respectively.

The percentage of semen induced head to head agglutin-ation in citrate diluted semen was 35.31vs 44.06 in Tris diluted samples.

The percentage of swollen sperm tail in HOST positive sperm cells was significantly higher (p < 0.01) in semen samples diluted in Tris diluents than in citrate diluents (58.44 vs 51.56%).

Percentage of spermatozoa induced acrosome reaction was 40.3 and 49.3% in thawed semen diluted in citrate and Tris diluents respectively.