
TY  - JOUR
A1  - Tudor, GD 
A1  - James, T 
A1  - Hunter, RA 
T1  - Seasonal growth and carcass characteristics of grazing steers implanted with trenbolone acetate and oestradiol
JF  - Australian Journal of Experimental Agriculture
JO  - Aust. J. Exp. Agric.
Y1  - 1992
VL  - 32
IS  - 6
SP  - 683
EP  - 687
KW  - 
UR  - https://doi.org/10.1071/EA9920683 
N2  - Measurements were made of the effects of Revalor on the seasonal growth, carcass weight and fatness of Zebu crossbred steers in central Queensland. Ninety-three steers were grazed on improved pastures for 15 months prior to slaughter. Half the animals were implanted with Revalor (140 mg trenbolone acetate plus 28 mg oestradiol-17B mixed with cholesterol) for the first 25 weeks (September-March) and the balance left as controls. During this period, treated steers gained weight significantly (P<0.001) faster than untreated steers (0.57 v. 0.42 kg/day). In March, the 2 groups were further divided into 2 subgroups and 1 subgroup from each group was either implanted for the first time or reimplanted with Revalor. The animals implanted in March were reimplanted again 4 months later. The other subgroups were not implanted. After implantation in March, steers implanted for the first time gained weight significantly (P<0.001) faster (1.27 kg/day) than all other treatment groups. Steers implanted at the beginning of the experiment in September, but not reimplanted in March, continued to gain significantly (P<0.05) faster in the period March-May than steers which had never been implanted (1.01 v. 0.85 kg/day). This suggests that the implant was still having an anabolic action at least 6 months after implantation. The experiment ended with the slaughter of the steers in December. Animals treated with Revalor at some time during the experiment were significantly (P<0.05) heavier at slaughter (about 22 kg) and had significantly (P<0.001) heavier carcasses (about 13 kg) than those left untreated. Steers implanted throughout the experiment and those implanted for the 9 months before slaughter had significantly (P<0.001) less subcutaneous fat at the P8 rump site than those either not treated or implanted earlier than 9 months prior to slaughter. 
ER  -

