Processing Yields as Affected by Dietary Potassium Chloride Concentration and Energy Level in Summer and Winter

Abstract

Equal numbers of male and female Cobb color-sexed broilers (28 days of age) were fed finisher diets containing 2665, 3056, or 3335 kcal ME/kg of diet. One-half of the birds on each dietary energy treatment were fed .75% potassium chloride (KCl) the last 5 days prior to slaughter. The experiments were conducted in winter (Feb to Mar) and in summer (Jul to Aug). Birds were processed and various yield parameters calculated. Raw ready-to-cook carcass composition was also determined.During winter, decreasing dietary energy level significantly decreased percent yield due to increased shrink. The addition of KCl to the diet in winter had no effect on yield characteristics and composition was affected only slightly by KCl treatment. In summer, percent shrink was significantly decreased as dietary energy level was decreased, whereas water uptake was significantly increased. This resulted in no dietary energy effect on ready-to-cook yield. Adding KCl to the diet in summer increased ready-to-cook yield by decreasing shrink. Fat was increased as dietary energy level was increased in both summer and winter. Moisture was inversely related to fat.