Artificial insemination (AI) is an important tool for genetic up-gradation of cows and buffaloes. Usual method for long term storage of bull semen is to add extenders/preservatives in freshly collected semen and store it in Liquid Nitrogen (at –196°C). This semen can then be stored for indefinite period.
Artificial insemination (AI) is an important tool for genetic up-gradation of cows and buffaloes. Usual method for long term storage of bull semen is to add extenders/preservatives in freshly collected semen and store it in Liquid Nitrogen (at –196°C). This semen can then be stored for indefinite period. The technique of AI was introduced in Pakistan a few decades ago; however it did not gain popularity in buffaloes due to poor pregnancy rate with frozen semen. One of the possible reasons has been inappropriate techniques used for freezing buffalo semen.
Detailed work was done to compare different preservatives, extenders and freezing techniques for buffalo semen. The preserved semen was evaluated for quality using the modern laboratory techniques. Based upon circular motility, curvilinear velocity, and lateral head displacement of sperm as evaluated by Computer Assisted Semen Analyzer, it was noted that post-thaw quality of buffalo semen could be improved using the Tris
Citric Acid buffering system. An optimum freezing rate was also determined for buffalo semen using computerized semen freezer. Furthermore, a new combination of antibiotics (gentamycin, tylosin and linco-spectin) to protect semen from germs proved to be better (conception rate on first service, 55%) than the conventional antibiotics (penicillin and streptomycin) (conception rate, 41.7%).
The newly developed technology was shared with provincial and regional semen production units through training courses, workshops and seminars. Presently this improved protocol is being practiced to freeze semen by a number of semen production units in the country.
Key References
Rasul Z, Anzar M, Jalali S, Ahmad N. (2000). Effect of buffering systems on post-thaw motion characteristics, plasma membrane integrity, and acrosome morphology of buffalo spermatozoa. Animal Reproduction Science 59:31–41
Andrabi SMH, Ahmad N, Abbas A and Anzar M. (2001). Effect of two different antibiotic combinations on fertility of frozen buffalo and Sahiwal bull semen. Pakistan Veterinary Journal. 21:166-169
