The effect of thyroxine on lactation in ewes

Summary

During the years 1955–57 inclusive measurements of growth rates have been obtained from some 289 lambs. Approximately half of these have been suckled on ewes implanted with l-thyroxine.

Growth rates of the lambs have been used to indicate the lactation level of the treated and control ewes.

Evidence of lactation response from the treated ewes has been obtained from (1) mature ewes implanted with thyroxine (a) six weeks before lambing, (b) two-three days after lambing, and (2) two-tooth ewes implanted about the time of mating.