Meeting Abstract

P3.139  Thursday, Jan. 6  Dietary fatty acid composition influences tissue lipid profiles and regulation of body temperature, but not metabolic rates, of hypothermic Japanese quail BEN-HAMO, Miriam*; MCCUE, Marshall D.; MCWILLIAMS, Scott R.; PINSHOW, Berry; Ben-Gurion University of the Negev, Israel; St. Mary’s University, San Antonio, Texas; University of Rhode Island, Kingston, Rhode Island; Ben-Gurion University of the Negev, Israel miriammi@bgu.ac.il

Many birds reduce their body temperature (T_b) to conserve energy during periods of inactivity, and we recently characterized how ambient temperature and nutritional stress interact with one another to influence hypothermic responses in Japanese quail (Coturnix japonica). Here, we examined how the fatty acid (FA) composition of the diet influences the FA composition of phospholipids in major organs and how these changes affect hypothermic responses and metabolic rates in fasted birds. For five weeks prior to fasting, quail were fed a standard diet and orally gavaged each morning with 0.7 ml of water (control) or a vegetable oil comprised of different predominant fatty acids, namely saturated fatty acids (SFA; coconut oil), unsaturated fatty acids (UFA; canola oil). Birds were then fasted for 4 d at an ambient temperature of 15 °C. We found that the SFA treatment group down regulated T_b during fasting, decreasing both photophase and scotophase T_b significantly more than the control group. Surprisingly, the greater decline in T_b of the SFA treatment group was not accompanied by a concomitant decrease in metabolic rate, and all three groups consistently had similar metabolic rates. This deeper hypothermic response was correlated with changes in the phospholipid composition of the skeletal muscle and liver that contained significantly more oleic acid (18:1) and less arachidonic acid (20:4), respectively. Our data implies that these two FAs may be involved in thermoregulation.