Korean J Vet Res.  2011 Mar;51(1):1-6.

Efficacy test of sustained-release somatotropin by implantation in steer, cow and barrow

• Kim NJ

Abstract

Sixteen steers were used to investigate the efficacy of the sustained-release implant of bovine somatotropin (bST) in improving growth and feed:gain ratio during 12 weeks. Administration of the 400 mg bST implant resulted in a 16.1% increase in growth rate, and this increase was significant (p < .05). The use of the sustained-release implant did not alter (p > .05) feed intake and feed:gain ratio. Thirty-four cows were used to investigate the efficacy of the sustained-release implant of bST in milk production during 4 weeks. Administration of the 200 mg bST implant resulted in an 8.7% increase in milk production, and this increase was significant (p < .05). Twenty-four barrows were used to investigate the efficacy of the sustained-release implant of porcine somatotropin (pST) in improving growth, feed:gain ratio and backfat thickness during 6 weeks. Administration of the 120 mg pST implant resulted in a 11.4% increase in feed:gain ratio and a 60% decrease in backfat thickness, and these results were significant (p < .05). But the use of the sustained-release implant did not alter (p > .05) growth rate and feed intake.

Keyword

feed:gain ratio; growth rate; implant; milk production; somatotropin; sustained-release

MeSH Terms

Growth Hormone
Milk
Growth Hormone