Study On The Apparent Digestibility Of Major Protein Sources And Optimum Requirement Of Protein To Lipid Ratio For Procambarus Clarkii

Procambarus clarkii is an important economic shrimp in China,and it has a high meat quality and high protein content.At present,there is a large demand for the Procambarus clarkii market,but there are few studies on nutrition and feed.Therefore,this study starts from the protein source and protein-lipid ratio,aim to screen out the high-quality protein source of Procambarus clarkii by the test and study its suitable protein-lipid ratio.Therefore,the research on the nutritional needs of Procambarus clarkii is perfected,which provides a scientific basis for the development of the special compound feed for Procambarus clarkii,and the development and production of Procambarus clarkii compound feed.A 30 days feeding trial was conducted to evaluate the theapparent digestibility of nutrient and amino acids of six ingredients were determined for Procambarus clarkii,to find a solution to the lumen of new protein feed raw materials.The results showed as follow,the total digestibility of raw materials of Procambarus clarkii was the highest in the imported fishmeal group,shrimp powder was significantly lower than other groups(P<0.05);the apparent digestibility of crude protein,the appearance of the rapeseed group The highest digestibility rate,soybean meal and shrimp powder group were significantly lower than other groups(P<0.05);apparent fat digestibility of crude fat was significantly lower than other groups(P<0.05),the highest in the meat group.For the shrimps of the original crayfish,the apparent digestibility of 17 kinds of amino acids in the imported fish meal,rapeseed meal and meat powder group exceeded 80%.The apparent digestibility of 17 kinds of amino acids in the shrimp feed group of the 6 feed ingredients was the lowest,except for the glycine table.In addition to the digestibility,the apparent digestibility of amino acids in the rapeseed group was the highest.A 90-day feeding trial was conducted to explore the appropriate protein and fat ratio of Procambarus clarkii.Results are as follows:With the increase of the ratio of protein-lipid in meal,the survival rate of Procambarus clarkii had no significant effect(P>0.05),and the body weight,weight gain rate,specific growth rate and feed coefficient of Procambarus clarkii were significantly different(P<0.05).).The meat content of Procambarus clarkii with a protein-lipid ratio of 2.92 was significantly higher than that of the protein-lipid ratio of 6.81(P<0.05),and the difference between the other groups was not significant(P>0.05).The increase of feed protein-lipid ratio had no significant effect on the crude ash of Procambarus clarkii(P>0.05).The crude lipid content protein-lipid ratio of 8.91 were significantly higher than the protein-lipid ratio of 2.92.Group,protein-lipid ratio of 3.5,protein-lipid ratio of 5.39,protein-lipid ratio of 2.92(P <0.05);protein-lipid ratio of 3.5 group of crude crayfish crude protein content was significant The group with a protein-lipid ratio of 2.92,the protein-lipid ratio of 4.3,the protein-lipid ratio of 5.39,the protein-lipid ratio of 8.91(P<0.05);the crude shrimp protein of Procambarus clarkii The lowest group(2.9%)with ratio of 5.39.The ratio of protein-lipid ratio in feed had no significant effect on the protein of Procambarus clarkii(P>0.05);the group with protein-lipid ratio of 2.92,the protein-lipid ratio of 2.92,the serum creatinine of Procambarus clarkii was significantly lower than protein and lipid The group with a ratio of 3.5,the protein-lipid ratio of 4.3,the protein-lipid ratio of 5.39(P<0.05);the protozoa crayfish alanine aminotransferase and aspartate aminotransferase decreased first and then increased;protein-lipid.The total protein content of Procambarus clarks in the ratio of 2.92 was significantly lower than that in the group with protein-lipid ratio of 2.92,the group with protein-lipid ratio of 3.5,and the protein-lipid ratio of 2.92(P<0.05).The group difference was not significant(P>0.05).The ratio of protein-lipid in meal had significant effects on intestinal lipase,protease and hepatopancreatic lipase and protease of Procambarus clarkii(P<0.05).As the ratio of protein-lipid in feed increased,the intestinal lipid of Procambarus clarkii The enzyme activity gradually decreased,the intestinal protease activity increased gradually;the hepatic pancreatic lipase gradually decreased,the hepatic pancreatic protease increased gradually;the feed protein-lipid ratio to the original crayfish intestinal,hepatopancreatic amylase have no effect.With the increase of the ratio of protein to lipid in feed,the acid phosphatase of 3 grams of Procambarus clarks in protein-lipid group was significantly higher than other groups(P<0.05),showing an upward trend;the protein-lipid ratio of 3.5,8.39,8.91,the alkaline phosphatase activity of Procambarus clarkii was significantly higher than that of the group with protein-lipid ratio of 2.92,the group with protein-lipid ratio of 4.3,and the group protein-lipid ratio of 6.91(P< 0.05);the highest ratio of lysozyme and superoxide dismutase active protein-lipid ratio was 5.39,which was 80.56 U/ML and 291.8 U/ML,respectively,and was significantly higher than the other groups(P<0.05).Conclusion: Imported fishmeal and meat powder are high-quality animal protein sources of Procambarus clarkii.Rapeseed is a high-quality plant protein source of Procambarus clarkii;suitable protein-lipid ratio ratio of feed can improve the immune performance of Procambarus clarkii and reduce liver function damage;The optimum protein-lipid ratio of Procambarus clarkii is between 5.81-5.94.