Effects Of Dietary Oil Sources On Growth Perfomance, Lipid Deposition And Blood Biochemical Index Of Carassius Auratus Gibelio

Lipid is the main nutrient elements in aquatic animals and plays an important role in aquatic feed, fish oil has historically been the dominant raw materials in the production of fish feeds. However, the limiting supply and high cost of fish oils, along with the possible accumulation of dioxins and dioxins-like PCBs in fish oils have forced the industry to investigate alternative lipid sources for use in fish diets. The objective of this study was to determine the impact of dietary lipid sources on growth, lipid deposition, blood biochemical index and fatty acid profile of Carassius auratus gibelio (average initial weight:6.04±0.05g). For the production of Carassius auratus gibelio feed, providing the nutrient composition of fat type and content of the choice of basis.1 Effects of dietary oil sources on growth performance and body composition of Carassius auratus gibelioFive experimental diets were formulated to contain 4% lipid originated from fish oil, soybean oil, lard, peanut oil and an mixed oil (fish oil:soybean oil:lard,3:4:3), respectfully. 525 healthy fish were randomly divided into five groups in the experiment. The feeding trial lasted for 60 days. Weight gain and specific growth rate (SGR) of fish fed mixed oil was significantly (P<0.05) higher than that of fish fed fish oil and lard, but not different from that of other groups. No significant difference was found among all treatments in protein efficiency ratio (PER) and feed conversion ratio (FCR). Mesenteric length/length of fish fed soybean oil was significantly (P<0.05) higher than that of fish fed fish oil and lard. Hepatosomatic index (HSI) of fish fed lard was significantly (P<0.05) higher than that of fish fed fish oil. However, visceralsomatic index (VSI) of fish fed lard was significantly (P<0.05) higher than that of fish fed mixed oil.Muscle protein content of fish fed lard was significantly (P<0.05) lower than that of other groups. However, no significant difference was observed among all treatments in moisture, lipid, ash and phosphorus content. Liver lipid content of fish fed lard was significantly (P<0.05) higher than that of fish fed fish oil and peanut oil, and liver protein content of fish fed fish oil and soybean oil were significantly (P<0.05) higher than that of fish fed lard and peanut oil. The results of this study indicated no significant difference on growth performance and body composition of Carassius auratus gibelio when soybean oil, peanut oil and fish oil were used solely. It also suggested that fish oil, soybean oil and lard could be mixed together as a better oil source for Carassius auratus gibelio, which not only reduced feed costs but also enhanced fish growth.2 Effects of dietary oil sources on activities of digestive enzymes, apparent digestibility and blood biochemical index of Carassius auratus gibelioThe conceputual design of raising was the same as that of the One. Intestine and liver protease activities of fish fed fish oil and soybean oil were significantly (P<0.05) higher than that of fish fed lard, but not different from that of the rest groups. Liver lipase activities of fish fed soybean oil and the oil mixture were significantly (P<0.05) higher than that of fish fed lard; whereas, the highest intestine lipid activities was found in fish fed the oil mixture. No significant difference was observed in intestine and liver amylase activities among all the treatments. Apparent protein and lipid digestibility of fish fed lard were significantly (P<0.05) lower than that of other groups.Total protein(TP) and albumin (ALB) of fish fed fish oil were significantly (P<0.05) larger than that of fish fed lard, group were lowest, but not different from that of the rest groups. The activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) of fish fed lard were significantly (P<0.05) higher than that of fish fed fish oil, there were no significant differences between other groups (P>0.05). The concentration of the triglyceride(TG) of fish fed fish oil was significantly (P<0.05) lower than that of fish fed lard, however, the concentration of the high density lipoprotein-cholesterol (HDL-C) of fish fed fish oil was significantly (P<0.05) higher than that of fish fed lard. No significant difference was observed in concentrations of albumin (ALB), total cholesterol (TC), blood glucose (BGLU), low density lipoprotein-cholesterol (LDL-C), and activities of alkaline phosphatase (AKP). In addition, the concentrations of cortisol, insulin (Ins) and glucagons (Glu) were no significant difference among all treatments (P>0.05). The results showed that lard is not conducive to fat metabolism, while fish oil can adjust and balance fat metabolism of fish, which promoted healthy growth of Carassius auratus gibelio.3 Lipid deposition, lipid metabolism enzymes and fatty acid profile of Carassius auratus gibelio fed different dietary lipid sourcesThe conceputual design of raising was the same as that of the One. Liver lipid content of fish fed fish oil was significantly (P<0.05) lower than that of the other groups; whereas, little difference was observed in intraperitoneal fat (IPF) ratio, muscle and viscera lipid content among all the treatments. Lipoprotein lipase (LPL) and hepatic lipase (HL) activities of fish fed fish oil was significantly (P<0.05) higher than that of fish fed lard and peanut oil. Saturated fatty acids (SFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of fish fed fish oil was significantly (P<0.05) higher than that of the other groups. In addition, the highest linoleic acid was found in fish fed soybean oil while the lowest in fish fed fish oil, no obvious differences from that of the rest groups. The results of this study indicated that fish oil can enhance the LPL and HL activities of Carassius auratus gibelio coupled with the relatively low liver lipid content; whereas, the opposite is ture for lard. Tissue fatty acid profile was significantly influenced by dietary FA composition.