Effect of Dietary Acidification on Mortality Rates, General Performance, Carcass Characteristics, and Serum Chemistry of Broilers Exposed to Cycling High Ambient Temperature Stress

A 2-phase (starter and grower) experiment was conducted to evaluate efficacy of a commercial phosphoric and citric acid based dietary acidifier (Lucta’cid) on broiler performance, survivability, serum chemistry, and carcass characteristics during cycling high ambient temperature stress. Starter phase acidifier supplementation (0 and 0.2% of diet) had no impact (P > 0.1) on broiler performance. The grower phase examined the 2 starter phase acidifier exposure histories along with 5 acidifier inclusion levels (0, 0.05, 0.10, 0.20, 0.30%) under cycling high ambient temperatures. A significant starter phase acidifier history × grower phase acidifier inclusion level interaction was noted on final BW, BW gain, and mortality. Mortality for birds lacking starter phase acidifier exposure declined quadratically (P < 0.05) with acidifier level, whereas no such response was noted for chicks consuming acidifier during the starter period. Broiler performance and survivability data, combined to estimate productivity per bird placed, indicated a continued mortality-driven acidifier history × inclusion level interaction (P < 0.10) on hot carcass weight, chilled carcass weight, breast yield, and leg quarter weight. Birds lacking starter phase acidifier and consuming acidifier during grower phase exhibited increased carcass, leg quarters, and breast yield per bird placed. In conclusion, data suggest that grower acidifier supplementation has the potential to reduce economic losses attributable to heat stress.