Dietary dried periphyton can improve growth, digestive enzyme, serum biochemical, antioxidant response and intestinal morphometric of Nile tilapia

The present trial was conducted to investigate the effect of inclusion of dried periphyton in Nile tilapia diets on growth, digestive enzymes activity, haematological, oxidative stress and intestinal morphometric parameters. Five isoproteic (32%), isolipidic (5%) experimental diets were formulated, to comprise graded levels of dried periphyton (0, 2.5, 5, 7.5 and 10 g kg(-1) diet). At the end of the feeding trial, the highest (P < 0.05) performance, feed utilization and survival rate were noticed in fish fed diet contained 7.5 and 10 g dried periphyton kg(-1) diet. Also, intestinal amylase and lipase activity were markedly (P < 0.5) higher in fish fed 7.5 and 10 g dried periphyton kg(-1) diet. Fish fed 10 g dried periphyton kg(-1) recorded the highest (P < 0.05) value of haemoglobin, haematocrit, red, white blood cells, neutrocyte, lymphocytes, monocytes and eosinophil count. The lowest level of alanine aminotransferase, aspartate aminotransferase and Alkaline phosphatas (AP) were observed in fish fed 10 and 7.5 g dried periphyton kg(-1) diet. Serum total protein, albumin, globulin, phosphorus and calcium were higher (P <= 0.05) in fish fed diets 5, 7.5 and 10 g dried periphyton kg(-1) diet. However, the lowest (P < 0.05) content of creatinine, cholesterol, triglycerides and low-density lipoprotein-cholesterol was noted in fish fed diets 7.5 and 10. Higher (P < 0.05) values of superoxide dismutase and catalase were observed in fish fed diet contained 10 g dried periphyton kg(-1) diet compared with other treatments. The lowest (P < 0.05) content of malondialdehyde content was attained by fish fed diets contained 7.5 and 10 g dried periphyton kg(-1) diet. The current feeding trial showed the suitability of periphyton as a dietary supplement and its supplementation up to 7 g kg(-1) diet in tilapia for improving growth, digestive enzyme, serum biochemical, antioxidant response and intestinal morphometric in Nile tilapia.