Environment and Management I

Due to the amount of time and effort required in measurement, often only a limited number of animals are assessed for individual feed effi­ ciency traits, and this can lower the amount of genetic progress made. Measuring the surface temperatures of the unfeathered areas of turkeys has been proposed as a method to monitor the proportion of feed energy ingested and metabolized. Theoretically, a low temperature would mean a bird is utilizing feed more efficiently by partitioning a larger amount of energy in body weight gain then into heat production. The aim of this trial was to assess correlations between feed efficiency traits, such as body weight (BW), body weight gain (WG), feed intake (FI), residual feed intake (RFI) and residual body weight gain (RG) with infrared thermography (IR) traits, such as head area temperature (tHEAD), eye area temperature (tEYE) and distal metatarsus temperature (tDM). The trial assessed 175 toms for FI and BW over a 6-wk period, from 16 to 22 wk of age, with measurements taken each week.At the end of each week IR images were taken using an IR camera (ThermaCamTM SC2000). Turkeys had ad libitum access to feed and water. All traits were adjusted for the fixed effects of line and hatch according to the model: Yij = μ + linei + hatchj + eij, using the GLM procedure of SAS. Traits were then compared using the CORR procedure in SAS. Correlations were low for both tHEAD and tEYE with all feed efficiency traits, however tDM showed low to moderate correlations between FI (0.04 to 0.34), BW (0.07 to 0.20), and WG (0.11 to 0.23). In the last 3 wk of the trial, tDM showed moderate correlations with RG (0.16 to 0.23) and these Pearson correlation coefficients are shown in Table 1.