J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J. Anim Sci. 1988. 66:1179-1185.
© 1988 American Society of Animal Science
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Jenkins, T. G.
Right arrow Articles by Klindt, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Jenkins, T. G.
Right arrow Articles by Klindt, J.

Postweaning Growth, Feed Efficiency and Chemical Composition of Sheep as Affected by Prenatal and Postnatal Testosterone

T. G. Jenkins, J. J. Ford and J. Klindt

U.S. Department of Agriculture1, Clay Center, NE 68933

Abstract

Data were collected from intact males, castrated males and ewe lambs to investigate the effect of presence or absence of testosterone prenatally and during the postweaning period on postweaning growth, feed intake and carcass chemical composition. Half the lambs from each sex were the progeny of dams that had received five injections of testosterone cyprionate from d 32 through d 87 of gestation. Linear contrasts were used to detect differences. Postweaning daily gain of intact males was greater (P < .01) than that of male castrates. Ewe lambs from treated dams had approximately 12% greater rate of growth (P < .04) than ewe lambs from control dams. Ewe lambs from dams that had been treated were 28% more efficient (P < .01) in the conversion of food to weightthan those from untreated dams. Ewe lambs from treated dams had heavier livers (P < .07). Carcass protein for intact males was greater (P < .11) than for castrates, and extractable fat was less (P < .05). Masculinization of growth characteristics of ewe lambs affected the quantity of carcass fat relative to control ewes (7.59 vs 8.92 kg). These ewe lambs also had more water in the carcass than did the control ewes (13.93 vs 12.29 kg). Administration of exogenous testosterone to pregnant ewes over an interval of time approximating time of sexual differentiation in the fetus enhances postweaning growth rate, feed conversion efficiency and chemical composition of genetic females.

Footnotes

1 Agric. Res. Serv., Roman L. Hruska U.S. Meat Animal Research Center, P.O. Box 166, Clay Center, NE 68933.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1988 by the American Society of Animal Science.