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Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude VII. Sexual activity in relation to age of ram

Published online by Cambridge University Press:  27 March 2009

R. B. Symington
Affiliation:
Department of Agriculture, University College of Rhodesia and Nyasaland

Extract

The effect of age on attainment of puberty and on seminal characteristics in yearling and mature rams was studied in German Merino, Persian Blackhead and indigenous Native rams living on Rhodesian highveld.

1. Puberty occurred at age and live weight proportional to mature live weight. Well-grown Native lambs ejaculated first at 169 days of age and 46 lb. live weight; Merino lambs when 250 days old and 79 lb. live weight and Persians were intermediate. Onset of sexual maturity was related more closely to live weight than to age, since runts ejaculated first at live weights close to those of well-grown lambs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1961

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