Abstract:
Three-year-old Hereford steers on winter pasture were implanted with 30 mg or 60 mg hexoestrol or two dosage levels of a paste formulation containing long-acting testosterone, progesterone, and oestradiol. In the 11- week experimental period all treated groups made significantly greater gains than controls (average gain, 0.93 Ib. a day), but in addition, variation in response differed between treatments. The importance of this aspect of hormonally-induced growth of cattle is discussed.