The use of enzymes as additives in broiler chicks diets

Abstract

TWO EXPERIMENTS WERE CONDUCTED IN ORDER TO EVALUATE THE USE OF ENZYMES (ALPHA-AMYLASES, XILANASES AND PROTEASES) AS FEED ADDITIVES ON THE PERFORMANCE OF BROILER CHICKEN. ONE THOUSAND PETERSON BROILER CHICKS AGED 1 DAY WERE EMPLOYED IN THE FIRST EXPERIMENT. THIS STUDY INCLUDED FOUR TREATMENTS: A) CORN SOYBEAN MEAL CONTROL DIET, B) CONTROL DIET ENZYMES, C) DIET 3 % LOWER IN BOTH CRUDE PROTEIN (CP) AND METABOLIZABLE ENERGY (ME), AND D) DIET 3 ENZYMES. EACH TREATMENT HAD FIVE REPLICATES OF 50 CHICKS EACH. THE SECOND EXPERIMENT WAS SIMILAR TO THE FIRST ONE, BUT THIS TIME SORGHUM SOYBEAN MEAL DIETS WERE EMPLOYED. EIGHT HUNDRED AND FORTY ARBOR ACRES CHICKEN AGED ONE DAY WERE USED WITH SEVEN REPLICATES OF 30 CHICKS PER TREATMENT. A COMPLETELY RANDOMIZED DESIGN WITH A 2 €” 2 FACTORIAL ARRANGEMENT OF TREATMENTS WAS USED IN BOTH EXPERIMENTS. FACTORS INCLUDED A LEVEL OF CP-, ME- AND ENZYMES INCLUSION. RESULTS OF THE FIRST EXPERIMENT FOR THE FOUR TREATMENTS AT 49 DAYS OF AGE WERE AS FOLLOWS: WEIGHT GAIN (2 372A, 2 425B, 2 154A AND 2 369B G) WAS DIFFERENT AMONG TREATMENTS (P < 0.01) WITH ENZYMES ADDITION; FEED CONVERSION (2.33A, 2.12B, 2.49 AND 2.24B) IMPROVED (P < 0.01) WITH THE ENZYMES ADDITION. IN THE SECOND EXPERIMENT, WEIGHT GAIN RESULTS (2 393, 2 408, 2 374 AND 2 387 G) AND BREAST YIELD PERCENTAGE WERE SIMILAR AMONG TREATMENTS (P > 0.05). HOWEVER, FEED CONSUMPTION (5 115A, 5 017B, 5 170A AND 5 008B) AND FEED CONVERSION (2.14A, 2.05B, 2.18A AND 2.10B) SHOWED SIGNIFICANT IMPROVEMENT WITH THE ENZYMES ADDITION. DATA OBTAINED SHOWED THAT THE ENZYMES INCLUSION ON CORN ORSORGHUM SOYBEAN MEAL DIETS FOR BROILERS IMPROVED WEIGHT GAIN, AND/OR FEED CONVERSION IN STANDARD DIETS, AND ALSO IN THOSE WITH LOWER CP AND ME CONTENT.