Study On The Application Of Different Oil Sources In The Channel Catfish Feed

The paper was conducted to study on the effect of tallow,fish oil, soybean oil and mixture of these in different proportion on nutrient digestibility and growth performance of channel catfish.Experiment 1 Effect of different oil source on nutrient digestibility of Channel Catfish240 channel catfish were chosen, the body weight was about 15g, and the fish were divided into 8 groups randomly, each group was consisted of 3 repeats and of 10 fish. Each group was feed with the same basal diet, but tallow, fish oil, soybean oil, mixed oil I (Tallow:Soybean oil=1:1), mixed oilⅡ(Tallow:Soybean oil.Fish oil=1:1:1), mixed oilⅢ(Soybean oil:Fish oil=2:3),mixed oil IV (Soybean oil:Fish oil=3:2), mixed oil V (Soybean oil:Fish oil=4:1) all were added in proportion of 4%Exogenous indicator method was adopted to study the effects of different oil sources on nutrient digestibility of channel catfish. The results showed that:the apparent digestibility of feed dry matter, fat, protein and energy of fish oil group were all higher than other groups; The apparent digestibility of fat,protein and energy of tallow group were all lower than fish oil group, soybean oil group and mixture group; The apparent digestibility of feed dry matter of soybean oil group was lower than fish oil group but higher than tallow group; The apparent digestibility of fat of soybean oil group was significant higher than tallow (P＜0.01),the apparent digestibility of protein and energy of soybean oil group were approach fish oil group and the two groups higher than the tallow group (P<0.05).The apparent digestibility of protein of mixed oil I group was significant higher than mixed oilⅡand mixed oil IV (P<0.05)Experiment 2 Effect of different oil source on growth performance of Channel CatfishExperimental diets and experimental treatment are same as Experimental 1. Study on the effects of different lipids on growth performance,physical indicators,back nutritional composition, biochmical indicators,metabolic enzyme activity of fat,blood physiological parameters of channel catfish. The results suggested that: (1) The effects of different oil source on growth performance of channel catfish is significant (P＜0.05).The growth rate and specific growth rate of fish oil group are the highest, but the bait coefficient is the lest among all groups. The soybean oil group is opposite to the fish oil group exactly.(2) The effects of different oil source on intestinal fat index of channel catfish is signifficant(P<0.05),but the fatness,visceral index,liver and pancreas index are all not signifficant (P>0.05)(3) The effects of different oil source on water,crude protein,crude ash of muscles of back are significant (P＜0.05),but the crude fat is not significant (P>0.05).The contents of water of mixed oil groupⅤis lowest among all groups, the different is significant (P＜0.05), but thecrude protein is higher than tallow group, fish oil,mixed oil group I and mixed oil IV (P＜0.05)(4) The effects of different oil source on blood serum biochemical parameters, such as GPT,GOT,AKP,TC,TG,HDL is all significant, the GPT of mixed oil group IV is highest and the mixed-oil group II was lower among the all groups. The GOT of mixed oil group I is highest and the mixed-oil groupⅢwas lower among the all groups.The AKP of fish oil group is highest,but the soybean-oil group was lowest The TC,TG of fish-oil group and mixed-oil groupIII were less than other groups significant (P<0.05). The HDL of tallow group was less than soybean-oil group, mixed-oil groupⅠ,mixed-oil groupIII (P<0.05).The LDL was not significant between each other (P>0.05)(5) The effect of different oil source on fatty acid synthase (FAS) activity is significant (P＜0.05). The FAS levels of fish oil group and mixed-oil group IV are less than tallow group and mixed-oil group I significantly (P＜0.05),the other groups have no significant different (P>0.05). The Lipase(LP) are not significant each other (P>0.05). The activity of serum lipase of tallow group is the highest among all groups, and the different is significant (P＜0.01).Meanwhile, the serum lipase of mixed oil groupⅣwas significant higher than the mixed-oil group II, mixed-oil groupIII (P＜0.01), but the fish oil group was significant less than mixed-oil groupⅣ(P＜0.05)(6) The effect of different oil source on the activity of SOD was not significant (P>0.05). The activity of CAT of soybean oil group was the highest, and was higher than fish oil group significantly(P<0.05), the other groups have no significant difference (P>0.05). At the same time, the activity of lysozyme(LSZ) of soybean oil group was significant higher than mixed-oil group I, mixed-oil group II, mixed-oil groupIII, mixed-oil groupⅣ(P<0.05). The MDA level of mixed-oil group I was the highest, then tallow group followed, the minimum was mixed oil group II and signifficant less than mixed-oil group I.(7) In all treatments, mixed-oil groupIV have the highest blood WBC,the lowest was mixed oil group II and the difference is significant between two groups (P＜0.01).At the same time, mixed oil group II was significantly lower than mixed-oil groupIII(P<0.05), there were not significant different between others(P>0.05). The hemoglobin of tallow group was the lest, it was significantly lower than mixed-oil group I, there were not significant different between others(P>0.05). The erythrocyte of fish oil group was the most,and significantly more than the mixed-oil groupⅡ, mixed-oil groupⅤ,the other groups have no signifficant difference.