Relationship of age, breed and libido with semen traits of cattle bulls

The present study was conducted to determine correlation of semen quality with libido in different breeds of bulls. Four mature cattle bulls from each of Friesian, Jersey, Achai, Cross (Friesian x Sahiwal) and Sahiwal in different age (1-3, 3-5 and above 5 years) were selected. For age grouping, data of the entire breed was pooled. Libido was measured in terms of time (seconds) taken for the entering arena until mounting (P1), time (seconds) taken from mounting the teaser until erection (P2) and reaction time (seconds) (P3). Semen was collected twice a week and analyzed for semen volume, sperm concentration, sperm motility, dead sperm percentage and hyposmotic swelling test (membrane integrity). The results revealed that libido score in term of P1 (6.6±0.46 Sec), P2 (1.88±0.07 Sec) and P3 (9.57±0.49 Sec) was significantly high (P<0.05) in Jersey breed, while crossbred bulls showed the lowest libido score. Jersey bulls showed significantly high (P<0.05) semen characteristics including sperm concentration (1560.0±59.00 x106/ml), membrane integrity (77.42±0.97%) and livability (83.32±8.32%). Libido calculated at different age groups showed that older animals having age above five years exhibited the best libido (P1, P2 and P3) compared to the younger animals. Similarly, semen characteristics including semen volume (6.50±0.73 ml) and membrane integrity (74.00±1.40%) were significantly high (P<0.05) in older bulls (above 5 years) compared to the young animals with no significant effect (P>0.05) on sperm concentration, motility and dead sperm percentage. Membrane integrity showed significantly high positive correlation with sperm concentration (r=0.52) and significantly low negative correlation with dead sperm percentage (r= -0.28). We concluded from the results that Jersey breed showed higher libido score and semen quality. Libido and semen quality were higher in Jersey bulls compared to the other breeds. Moreover, libido and semen quality increased with increasing age (up to 8 years).