Submitted to: Animal Science Progress Report
Publication Type: Other
Publication Acceptance Date: October 12, 1999
Publication Date: N/A
Technical Abstract: Anabolic implants are an integral part of beef production. This study was to test similar implants in pigs. Fifty-four crossbred barrows were blocked by weight at 53 d and randomly assigned within block to treatment. Treatments were one of three compounds implanted in the ear at 56 d. Implants were a sham implant (control), 120 mg trenbolone acetate (TBA)/24 mg estradiol (E2)(TBA/E2,5:1) or 120 mg TBA/12 mg E2 (TBA/E2,10:1). At 56 d pigs were penned in trios by weight within treatment. Feed disappearance and ADG were measured weekly and used to calculate the gain to feed ratio (G:F). There were no differences among treatments for ADG or real-time ultrasound LEA. Least-squares means and standard errors for G:F from 56 d to slaughter at 118 kg were 0.333 +/ .010, 0.36 +/ .010 and 0.357 +/ .010 for controls, TBA/E2,10:1 and TBA/E2,5:1, respectively. Covariance analysis of this trait revealed no significant treatment effect (P=0.1239). .Pairwise comparisons showed tendencies for treatment differences which wer not significant (P=0.059 and P=0.113 for control vs TBA/E2,10:1 and control vs TBA/E2,5:1, respectively). When control was compared to the mean of the other two treatments combined, a difference was detected in G:F (P=0.048). If approved for use in swine, TBA/E2 may prove to be a valuable tool to enhance efficiency of swine production.