Effects of replacing soybean meal protein with cottonseed protein concentrate on the growth condition and intestinal health of Nile tilapia ( Oreochromis niloticus )

Abstract

With the development of processing technology, cottonseed protein concentrate (CPC) has been widely used as a new protein source to replace fish meal in aquaculture. But whether CPC can replace soybean meal still needs investigation. A ten-week experiment was designed to evaluate the impact of replacing soybean meal (SBM)[45%], CPC75 [75%] and CPC100 [100%]) on Nile tilapia (Oreochromis niloticus). The results showed that 45% or higher CPC substitution significantly retarded the growth performance. Increased intestinal permeability was found in the CPC75 and CPC100 treatments. To investigate whether the residual gossypol is account for the intestinal dysfunction, an 8-week feeding trial including a control diet (CON), a control diet supplemented with 150 mg/kg gossypol (ML) and 300 mg/kg gossypol (MH) treatments, was conducted. The results showed that the transepithelial resistance (TER) was significantly decreased in MH treatment. In conclusion, the replacement of 30% SBM protein by CPC can be used for Nile tilapia's dietary needs, while 45% or higher CPC substitution of SBM influenced the intestinal health and growth condition of Nile tilapia.

Intestinal Microbiota Mediates Gossypol-Induced Intestinal Inflammation, Oxidative Stress, and Apoptosis in Fish

“…The previous results in cell experiments suggested that the aldehyde group of gossypol induced apoptosis via the ROS-SIRT1-p53-PUMA pathway in male germline stem cell, and gossypol induced apoptosis in ovarian cancer cells through oxidative stress . Studies from ruminants suggested that the gossypol-degrading bacteria in the rumen play a critical role in the tolerance to gossypol. , However, dietary gossypol could affect the growth condition and intestinal health of aquatic animals, including poor growth conditions, morphological damage to the midintestine, and decreased antioxidant capacity. − Studies showed that dietary gossypol could aggravate enteritis, damage the structure of intestinal epithelial cells, and increase the intestinal permeability. , However, it is not clear how the negative effects of gossypol are exerted in the intestine and whether intestinal microbiota of fish is involved in this progress.…”

“…CPC has been used to replace fish meal in the feed of several aquatic animals, ,, and our previous study also showed the feasibility of CPC in replacing soybean meal in omnivores . However, the presence of gossypol in CPC greatly limits its application in aquafeed.…”

“…A study in turbot ( Scophthalmus maximus L.) showed that gossypol in the diet had little impact on digestive enzyme activities and intestine morphology but it caused liver fibrosis and induced chemokine and proinflammatory cytokine secretions, while another study showed that dietary gossypol could aggravate enteritis and damage the structure of intestinal epithelial cells in grass carp ( Ctenopharyngodon idella ) by up-regulating the pro-inflammation cytokines and down-regulating the anti-inflammatory cytokines in the intestine . In our previous study, we also found that gossypol remaining in the CPC was the main cause of weight loss and intestinal structure damage in Nile tilapia ( Oreochromis niloticus ) . However, the underlying mechanism of the negative effects of gossypol in fish gut remains unclear.…”

“…3 CPC has been used to replace fish meal in the feed of several aquatic animals, 2,4,5 and our previous study also showed the feasibility of CPC in replacing soybean meal in omnivores. 6 However, the presence of gossypol in CPC greatly limits its application in aquafeed. A study in turbot (Scophthalmus maximus L.) showed that gossypol in the diet had little impact on digestive enzyme activities and intestine morphology but it caused liver fibrosis and induced chemokine and proinflammatory cytokine secretions, 7 while another study showed that dietary gossypol could aggravate enteritis and damage the structure of intestinal epithelial cells in grass carp (Ctenopharyngodon idella) by up-regulating the pro-inflammation cytokines and down-regulating the anti-inflammatory cytokines in the intestine.…”

“…8 In our previous study, we also found that gossypol remaining in the CPC was the main cause of weight loss and intestinal structure damage in Nile tilapia (Oreochromis niloticus). 6 However, the underlying mechanism of the negative effects of gossypol in fish gut remains unclear.…”