Effect of Organic Zinc Supplementation on Semen Production and Quality in Kankrej Bulls

Background: Zinc is found in very high concentration in semen and male reproductive tract and acts as a hormone receptor modulator for testosterone production in Leydig cells. Thus, it plays a very important role in male reproduction. Moreover, Indian soils are very deficient in zinc as per earlier reports and recent studies have shown that supplementation of zinc has improved qualitative as well as the quantitative aspects of semen quality in bulls. So, a study has been planned to study the effect of organic zinc supplementation on semen production and quality in kankrej bulls.
Methods: A total of 8 healthy Kankrej bulls under semen collection were selected for the study. Basal diet (concentrate mixture, green and dry fodder) was fed during pre-supplementation and zinc propionate @ 100 ppm/bull was supplemented to the basal diet during post-supplementation for a period of 60 days to complete one spermatogenic cycle. A total of 128 ejaculates (64 pre-supplementation and 64 post-supplementation) were collected. Result: Mean semen volume was non-significant (P greater than 0.05) between the treatment groups. Mean sperm concentration was 1325.68±80.08 and 2162.36±112.0 million/ml pre- and post-supplementation, respectively. Feeding of zinc propionate significantly (P less than 0.01) increased semen sperm concentration. The average mass motility of sperms was significantly (P less than 0.01) higher during post-supplementation (3.92%) than the pre-supplementation (3.78%). The overall live sperms were significantly (P less than 0.01) higher during post-supplementation (73.33±0.91%) than the pre-supplementation (63.53±1.03%). It may be concluded that supplementation of 100 ppm of zinc propionate in the diet of Kankrej bulls improved semen quality in terms of quantitative and qualitative characteristics of semen.
