HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Cox, J. L. Articles by Jensen, A. H. Search for Related Content PubMed PubMed Citation Articles by Cox, J. L. Articles by Jensen, A. H.

Influence of Ambient Temperature Stress on Response of Pregnant Rats to Dietary Protein Levels

Illinois Agricultural Experiment Station, Urbana

Abstract

Three experiments involving 192 pregnant rats were conducted to determine the influence of temperature on the response to protein levels. Dietary protein levels were 5, 10, 20 and 30% in all experiments. Temperature treatments were 7, 23 or 33° C. in experiments 1 and 2, and 7 and 23° C.in experiment 3. Temperature, protein level and time of initial exposure were observed to have little influence on embryo survival. Weight gain of the dam was less at 7 and 33 than at 23° C. and increased with increasing protein levels except at 33° C.

Nitrogen retention of the dam was linearly correlated with protein intake during early gestation. The amount of nitrogen retained by the rats decreased as gestation progressed with rats consuming the high protein diets showing the greatest decline. This decline in nitrogen retention may reflect an increased energy requirement during midgestation.

In the latter stages of gestation, the amount of nitrogen retained increased over the preceding period. Nitrogen retention was the greatest in rats fed the 20% protein diet at 23 and 33° C. However, at 7° C. it appeared that consumption of the 20% protein diet did not always support the greatest nitrogen retention. However, feeding the 10% protein diet generally resulted in greater nitrogen retention than feeding the 5% protein diet at all stages of gestation at each temperature.

¹ Present address: Merck Institute for Therapeutic Research, Rahway, New Jersey.

² This paper represents part of a thesis submitted by the senior author to the Graduate College of the University of Illinois as partial fulfillment of the requirements for the Ph.D. degree.