The effects of chronic handling on the incidence of leg abnormalities and several blood parameters in turkeys.
Twelve hundred day-old Nicholas toms were randomly distributed among 47 pens as part of two experiments designed to evaluate the effects of chronic handling on leg weakness and several blood parameters. From 5 until 19 weeks of age, one half of the birds, designated as the handled group, was subjected to physical examination once each day, 5 days a week, in an effort to detect the development of leg abnormalities. They were also removed from their pens and weighed at 5, 10, 15, and 20 weeks of age. The remaining birds, referred to as nonhandled, were exposed to the minimum amount of human contact necessary for proper management. Experiment 1 involved only birds in the handled group. When a leg weakness was detected, the afflicted bird and a healthy control from the same pen were bled. Determinations were made of packed cell volume, hemoglobin concentration, total leukocyte count, and the plasma levels of uric acid, inorganic phosphate, calcium, alkaline phosphatase activity, testosterone, and corticosterone. Lame birds were found to have significantly higher total leukocyte counts and plasma corticosterone concentrations than healthy controls, the other parameters being unaffected. Experiment 2 was performed using both handled and nonhandled birds, 19 weeks of age. Lame and healthy subjects from each group were selected. Blood parameters identical to those in Experiment 1 were measured; it was found that lame birds had significantly higher plasma corticosterone levels than healthy controls and that chronic handling caused significant decreases in packed cell volume, uric acid, alkaline phosphatase activity, and corticosterone. Handling did not affect the incidence of leg weakness or mean final body weight.