The present study was conducted to determine the effect of buffalo milk versus cow milk on the longevity of buffalo and cow bulls semens. Two buffalo and two cow bulls were used for collection of semens. These bulls were 3-9 years of age and were maintained under similar conditions at Artificial Insemination Centre, College of Animal Husbandry, Lahore. The milk used was obtained form the same cow and buffalo throughout the study. A total of 16 samples were collected from the four bulls.Physical and Microscopical examinations were conducted to evaluate the semen and samples with 4 or above mass motility were used in the experiment. Two fractions of each extender (buffalo and cow milk) were made. First was heat treated at 90 o c but not homogenized and second was heated at 82.2o c and homogenized. The glycerol in 10 and 20% ratio was added to the diluents alongwith 1000 units of penicillin and 1 mg. of streptomycin per ml. of extended semen. The dilutions were made in 1:10, 1:20 and 1:30 extensions of both buffalo and cow-bull semen in both extenders. The semen was preserved at 5oC in the refrigerator, and observations were made on each day at even hours, for 7 days.
The data so collected were subjected to the analysis of variance, statistically and mean motility rates were also calculated to determine the comparative effects of cow milk and buffalo milk on the preservation of cow-bull and buffalo-bull semen. The study revealed:-
1. That the semen was preserved comparatively better in heat treated milk than homogenized milk both in buffalo and cow milk. This was due to the difference in heating temperature and durations in both treatments.
2. Each buffalo bull's and cow Bull's extended semen with 10% glycerol gave significantly higher motility than with 20% glycerol in both milk (buffalo and cow).
3. The motility percentage was preserved better with high concentrations of sperms than with lower concentrations. The dilution ratio in 1:10 indicated the better results than the other two extensions of 1:20 and 1:30.
4. The cow-bull semen was preserved better in both the extenders for the longer period of time than buffalo-bull semen. However the semen was preserved significantly better in buffalo milk than in cow milk.
5. That in fluid semen extension the use of buffalo milk is recommended in field for future and determination of its effects on conception rates is open for further research.