The Effect of Using Organic Acid as an Alternative to Antibiotics Drugs on Productive and Physiological Performance of Broilers Ross 308

摘要

An experiment was conducted to study the effect of graded levels of butyric acid (butyrate) on performance, gastrointestinal tract health and carcass characteristics in young broiler chickens. Control starter (0-3 wk.) and finisher (4-6wk.) diets were formulated to contain 2,900 kcal ME/kg and 23% CP, and 3,100 kcal ME/kg and 21% CP, respectively. Subsequently, four groups of diets were formulated as following (T1: Positive Control contain 0.05% antibiotic maudramycin), (T2 : Negative Control without maudramycin), (T3 : T2 + 0.3% butyric acid) and (T4 : T2 + 0.6% butyric acid). Each diet was fed at random to 4 replicates of 30 chicks each throughout the experimental period (0-6wk). The results showed that 0.3% and 0.6% butyrate in the diet was improvement the body weights more than other treatments, and superior for feed conversion ratio. Feed intake were not influenced by the dietary treatments. A reduction in pH of the upper GI tract (crop, proventiculus and gizzard) was observed by inclusion of butyrate in the diets of broilers compared to either control or antibiotic-fed group. Butyrate at 0.6% was more effective in reducing the pH than 0.3%. Within the lower GI tract, 0.6% butyrate was effective in lowering pH in the jejunum, but no effect was found in either the duodenum or ileum. Dressing percentage was higher in all the butyrate treatment groups compared to the positive control or negative group also Increasing of histomorphological response. The best rate of villi length was recorded in the fourth and third treatments compared to the lowest length of treatment in the second and first treatment. From these findings, it is concluded that 0.3 and 0.6% butyric acid supplementation lead to more high villi and mucosal thickness at small intestine, and increasing dressing percentage in broiler chickens.