Use of a fat probe to assess variation in abdominal fat in broilers

Four trials were conducted to compare the fat probe measure of abdominal fat with that of actual abdominal fat weights and percentage abdominal fat. Various ages, diets, and genetic groups were used to provide experimental chickens with a wide range in body weights and abdominal fat percentages. Mean values obtained by two operators using the probe on the same bird were similar (correlations of .70 to .79). Considering all comparisons, the arithmetic mean of the correlations between fat probe values and percentage abdominal fat was .24; values ranged from .01 to .44. In five comparisons of groups differing significantly in percentage abdominal fat, there were no significant differences in probe values, and correlations between fat and probe values were low. In three other comparisons of groups differing significantly in percentage abdominal fat, differences between probe values were significant and correlations between fat and probe values were moderate. In the comparison groups in which there was an association between probe and fat values, the magnitude of the differences in fat values was about four times as great as that of differences in probe values and the correlations were moderate (.28 to .44). In the comparisons in which higher abdominal fat. In comparisons where higher probe values were not associated with higher abdominal fat, higher body weights were not associated with higher percentage fat.