Growth performance, breeding behavior and semen characteristics of purebred and crossbred boars [Philippines]
1985
Alcantara, P.F.
The number of feeding days to reach the desired weight of 90 kg, feed consumption, and feed efficiency were not significantly different among breeds. The crossbred boars were slightly younger than the purebreds at first successful semen collection. Semen characteristics at different ages of the boars were also not significantly different among breeds. However, semen volume and number of sperm per ejaculate were significantly greater in crossbred boars at 7 months old. The crossbred boars were also faster in mounting the gilt and in thrusting their penis, and stayed longer on top of the gilt during ejaculation. Moreover, crossbred boars persistently performed better on successive semen collections than purebred boars. The quality of semen of older boars was better than that of younger ones. Semen collected every other day was also better in quality than the semen which was collected daily. The results also indicated that successive semen collection adversely affects semen characteristics. Frequent semen collection was also observed to reduce sperm production and semen quality. Boars subjected to daily semen collection required longer time for their semen to return to normal compared to boars on skip-a-day semen collection
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