Promoting growth and controlling diseases has always been the two main directions of aquatic animal research. Proteins and amino acids play an important role in fish body composition and metabolism. However, fish cannot synthesize all the amino acids they need, and the lack of essential amino acids will lead to a decrease in fish growth performance and feed efficiency [1-2] . Arginine is one of the 10 essential amino acids in fish [3] . It is involved in protein synthesis, promotes endocrine and regulates body immunity in fish. In recent years, studies have shown that arginine also has a good regulatory effect on animal fat, and it is currently believed to play its role mainly through the nitric oxide pathway [4] .
N-carbamoylglutamic acid (NCG) is a structural analog of N-acetylglutamate (NAG) that acts in the body of the animal to participate in the urea cycle of the body like NAG. Studies have shown that NAG is an essential cofactor and limiting factor for the endogenous synthetic pathway of arginine [5] . In terrestrial animals, NO can be produced through the urea cycle, thereby regulating the cardiovascular system and immune system. The role of NCG in fish and lower organisms is less studied.
Cheng Weixuan et al [6] conducted a two-month test on fat deposition of tilapia juveniles (3 cm in length) by NCG, and found that the addition of 0.25 g NCG/ton of feed liver was reduced by about 1/3. Table 1).
Table 1 - Effect of test feed on Nile tilapia visceral index
Based on this, our company also carried out NCG experiments on the liver index and the body index of juvenile turbot (full length 8cm). The results showed that the liver of the NCG group was significantly higher than that of the control group. Decline, the decline is above 14%. The liver-to-body ratio and the visceral ratio showed a downward trend with the addition of NCG, and the 0.8 group (ie, adding 0.8 g NCG/ton of feed) was the best (see Table 2).
Table 2 - Comparison of visceral indicators between different concentrations of NCG additive and control group
Wang Liansheng et al [7] used NCG-added corn gluten meal instead of fish meal to raise hybrid carp. It was found that the average terminal weight, weight gain rate and protein efficiency of the hybrid carp of the experimental group with 500gNCG/ton of feed increased by 12.2% and 13.73, respectively. % and 9.58%; the feed coefficient decreased by 10%; the average dead weight, weight gain rate and protein efficiency of the hybrids in the experimental group supplemented with 1000g NCG/ton of feed increased by 18.93%, 21.5% and 19.58%, respectively; 19.28% (see Table 3).
Table 3 - Effect of adding different doses of NCG on the growth of hybrid
Because the application of arginine in aquatic products is limited by many factors such as crystal moisture absorption, water solubility, storage difficulties, arginine-lysine antagonism [8] . NCG can effectively replace NAG, and further produce NO by producing endogenous arginine, which can improve the growth rate of fish on the one hand, and regulate the fat synthesis and decomposition of liver and viscera through nitric oxide pathway on the other hand, in case Control the occurrence of fatty liver and hepatobiliary syndrome.
References:
[1] Alam MS, Teshima S, Koshio S, etal. Arginine requirement of juvenile Japanese flounder Paralichthys olivaceus estimated by growth and biochemical parameters [J]. Aquaculture, 2002, 205:127-140.
[2] Masagounder K, Hayward RS, Firman J D. Comparison of dietary essential amino acid requirements determined from group-housed versus individually-housed juvenile bluegill, Lepomis macrochirus [J]. Aquaculture Nutrition, 2010, 17: 559-571.
[3] NRC (National Research Council). Nutrient requirements of fish
And shrimps[S]. Washington, DC National Academy Press, 2011.
[4] Jobgen WS, Fried SK , Fu WJ, et al.Regulatory role for the arginine-nitric oxide pathway in metabolism of energy substrates [J] .Journal of Nutritional Biochemistry, 2006,17 (9): 571-588 7vW
[5] HALL LM, METZENBERG RL, COHEN P P.Isolation and characterization of a naturally occurring cofactor of carbamyl phosphate biosynthesis EJ].J Biol Chem, 1958, 230:1013-1021.
[6] Guangdong Institute of Microbiology. Application of N-carbamoyl glutamic acid in the preparation of preparations for reducing liver fat content and/or increasing muscle fat content in fish: China, CN 104000023 A[P], 2014.08.27.
[7] Heilongjiang Fisheries Research Institute, Chinese Academy of Fishery Sciences. Adding N-carbamoyl glutamic acid squid high corn protein powder feed: China, CN104431436 A[P], 2015.03.25.
[8] Buentello JA, Gatlin D M.Effects of elevated dietary arginine on resistance of channel catfish to Edwardsiella intaluri [J]. of Aquatic Animal Health, 2001, : 194-201.
Komatsu Filter,Komatsu Fuel Filter,Komatsu Excavator Filter,Komatsu Genuine Filter
JINING SHANTE SONGZHENG CONSTRUCTION MACHINERY CO.LTD , https://www.sdkomatsugenuineparts.com