Effects of the addition of sumac extract on growth performance, serum biochemistry and intestinal microbioata in broilers at different stocking densities

In this study we aimed to evaluate the effects of dietary supplementation of sumac powder (Rhus coriaria) on growth performance, serum biochemistry and intestinal microbiota in broilers reared at different stocking densities. A total of 378 one-day-old Ross 308 male broiler chicks were subjected to a 2 stocking densities (10 and 20 chicks/m2 floor area; normal and high stocking density) x 3 sumac powder levels (0.0, 0.75 and 1.5 g/kg feed) factorial arrangement of treatments. Body weight gain and feed intake were significantly lower in chickens reared at high stocking density than normal stocking density groups (P<0.05). Moreover, feed conversion rate was negatively affected by high stocking density (P<0.05). Dietary addition of sumac powder had no effect on these variables in both stocking densities (P>0.05). Both stocking densities and the supplementation of sumac powder to the feeds had a reducing effect on intestinal weight (P<0.05). Serum total protein concentration of chickens reared at high stocking density was higher than those of the control groups (P<0.05). There was interaction between stocking density and dietary sumac powder supplementation for only body weight gain and abdominal fat variables at the end of the study (P<0.05). However, no differences were observed for the relative weight of liver, spleen, gizzard and proventriculus (P>0.05). In addition, alkaline phosphatase (ALP), aspartate amino transferase (AST) activities and high density lipoprotein (HDL), cholesterol and triglyceride concentration in the serum were not influenced by the any stocking density and sumacpowder supplementation (P>0.05). In conclusion, our results showed that broilers exhibited low performance when reared at high stocking density and dietary supplementation of sumac powder has not prevented this decline.