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


     

J. Anim Sci. 1975. 40:1130-1135.
© 1975 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 Anderson, R. R.
Right arrow Articles by Harness, J. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Anderson, R. R.
Right arrow Articles by Harness, J. R.

Thyroid Hormone Secretion Rates in Growing and Mature Goats1

R. R. Anderson2 and J. R. Harness

University of Missouri Columbia, 65201

Abstract

Dairy goats of four major breeds were used to determine the relationship between thyroid hormone secretion rate (TSR) and body weight. Goats ranged from 2 weeks to 6 years of age and 3 kg to 95 kg body weight. Twenty females were subjected to a total of 105 TSR determinations, while 14 males had 39 determinations. TSR was run every 3 months. TSR (mg/day) was related to body weight (kg) and the 3 primary measures used to calculate TSR (concentration in body pool, size of pool in liters, and rate of disposal of thyroxine from the body pool). Correlation coefficients were: thyroxine concentration and pool size, .038; thyroxine concentration and disposal rate, —.40; thyroxine concentration and TSR, .53; pool size and disposal rate, —.41; pool size and TSR, .72; and disposal rate and TSR, —.26. Age and TSR had a R2value of .35, while for body weight and TSR it was .53. When body weight and TSR were expressed as logarithms to comply with the mathematical expression Y = aXb, the R2 value was increased to .64. Pooling linear and quadratic effects of the logarithmic data resulted in R2 of .65, indicating no significant quadratic effect. A prediction equation developed for all 144 determinations was the following: Y (TSR, mg/day) = .010 x (body weight, kg).69. In other words, for every unit increase in body weight, there was a .69 unit increase in TSR. Prediction equation for 39 determinations on males was Y = .013 x .63 with R2 of .64, while it was Y = .010 X .70 for 105 tests in females with R2 of .63.

Footnotes

1 Contribution from the Missouri Agricultural Experiment Station. Journal Series No. 7124. Approved by the Director.

2 Department of Dairy Husbandry, University of Missouri, Columbia 65201.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1975 by the American Society of Animal Science.