Effects of Synovex C® implants on growth rate, pelvic area, reproduction, and calving performance of replacement heifers

R. F. Hancock, G. H. Deutscher, M. K. Nielsen, D. J. Colburn
1994 Journal of Animal Science  
Two trials were conducted to evaluate one trial, pregnancy first 21 d and total pregnancy in effects of Synovex C@ implants on replacement heifers, 63-d breeding season were decreased ( P = . 0 5 ) by given at two different ages. Crossbred heifer calves ( n implanting at 6 mo. At subsequent calving, an = 370) were allotted t o four treatments: 1) non-interaction existed between the effects of the implanted controls, 2) implanted at 2 mo, 3 ) im-2-and the 6-mo implant for calf birth weight and
more » ... anted at 6 mo, and 4) implanted at both 2 and 6 mo pelvic area:birth weight ratio. A single implant at of age. Heifers implanted at 2 mo gained 7 kg more ( P either 2 or 6 mo decreased ( P = . O l ) calving difficulty = .01) by 6 mo than those not implanted at 2 mo. No score; and implanting at both 2 and 6 mo showed the differences were found in 22-mo weights. All im-greatest reduction in calving difficulty. Implants had planted heifers had larger ( P = .01) yearling pelvic no significant long-term effects on reproduction or calf area than controls. All heifers implanted at 6 mo production of 2-yr-old cows. Results showed implantcontinued to have larger ( P = .01) pelvic area at 22 ing at 2 mo of age increased early weight gain and mo. All implanted heifers had higher ( P = ,051 decreased calving difficulty scores; implanting at 6 mo occurrence of non-ovulatory estrus. No differences increased precalving pelvic area and decreased calving were found among treatments in percentage of heifers difficulty scores; and implanting at both 2 and 6 mo puberal before breeding, in estrus first 21 d of increased early weight gain, decreased calving diffibreeding, or in first-service conception rate. In only culty scores, but tended to reduce early fertility.
doi:10.2527/1994.722292x pmid:8157513 fatcat:voigxxrqxvbi5phvtoiarisa6i