DefinePK

Abstract

The study evaluated the impact of enzyme-treated soybean meal with yeast (HP AviStart; HPA) on broiler performance, nutrient digestibility, and carcass quality. A total of 900 Ross 308 chickens of mixed sexes were randomly allocated to six treatments, each with six repetitions. The dietary treatments were corn-soybean diet with HPA 5% replacement soybean meal in four treatments: 1-10d for pre-starter; 1-21d for both pre-and starter in combination with methylene disalicylate (BMD) in pre-starter (1-10d) and 1-21d for both pre- and starter compared with the control (corn soybean diet) and the control with BMD in feeding. The overall study (1–42d) showed that the overall feed conversion ratio values were similar to those of BMD or HPA, but they were much better than the control group (P<0.05). They were also better for the percentage of survival rate, the productive index, and the drop in feed cost per gain, but these differences were not significant. However, supplemental HPA, including 5% replacement of SBM in the control diet, showed evidence of economic returns and showed a higher return on investment than the control group; it was higher when supplementing HPA for the whole period of the pre-starter and starter diets (1-21d). For nutrient digestibility in 21-year-old broilers, the results showed better significant digestibility of crude protein, ether extract, calcium, and phosphorus when broilers were fed with HPA or HPA plus BMD in the diets (P<0.05). There were no big differences in the carcass’s quality or the organs’ weight between the treatments. However, the white stripes on the breast meat got significantly less noticeable (P<0.05), and footpad lesion scores decreased in all treatments that included HPA in the feed. Supplementation with HPA showed a significant increase in fat deposition in the small intestine at 42d of age versus the control and antibiotic BMD groups (P<0.05). HPA supplementation (1-10d or 1-21d) promotes antibiotic growth with improved broiler performance and carcass quality and, thus, a higher return on investment. These data indicate that HPA provided both a high quality of protein and metabolizable energy value compared to a control diet.Keywords:Broiler, Enzyme treated soybean meal, Performance, Nutrients digestibility, Carcass quality.