Greathead K D
Aust Vet J. 1984 Jan;61(1):20-2. doi: 10.1111/j.1751-0813.1984.tb07124.x.
Four-month-old beef calves were implanted with 36 mg zeranol, and their growth compared with untreated calves. Treated steer and heifer calves gained 10 kg more bodyweight to weaning at 7.5 months of age. The trial was conducted at 2 research centres and calves at both centres showed significant responses for the first 45 days (P less than 0.001) after treatment but during the following 30 days only calves at one centre showed a continued response (P less than 0.05). No differences in growth rate occurred between treated and untreated calves over the final 30 days before weaning at either centre. The backfat measurement of untreated animals increased more than that of the implanted animals (P less than 0.05) at one centre but not at the other.
给4月龄的肉牛犊植入36毫克玉米赤霉醇，并将它们的生长情况与未处理的牛犊进行比较。经处理的公牛犊和母牛犊在7.5月龄断奶时体重增加了10千克。该试验在2个研究中心进行，两个中心的牛犊在处理后的前45天均表现出显著反应（P小于0.001），但在接下来的30天里，只有一个中心的牛犊表现出持续反应（P小于0.05）。在任何一个中心，断奶前最后30天里，经处理和未处理的牛犊在生长速率上均无差异。在一个中心，未处理动物的背膘厚度增加量比植入动物的更多（P小于0.05），但在另一个中心并非如此。
