Requirement Of Water-soluble Vitamin B1, B2 And B6 Of Juvenile Chinese Mitten Crab, Eriocheir Sinensis

Using vitamin-free casein as the protein source,fish oil as fat source,and dextrin as carbohydrate source to formulate the basel diet,and add different levels of vitamin B₁,B₂ and B₆.The feeding trials were undertaken to determine the effect of vitamin B₁,B₂,and B₆ on the nutrition physiology of Chinese mitten crab,Eriocheir sinensis, and the optimum requirement of the there vitamins respectively according to the growth performence,some metabolism factors and body compositon.1.Dietary vitamin B₁ Requirement of junvenile Chinese mitten crab,Eriocheir sinensisThe objective of the study was to determine vitamin B₁ requirement of junvenile Chinese mitten crab,Eriocheir sinensis.The basal diet was formulated using vitamin B₁-free casein as the protein source.Eight graded levels(0,10,20,40,80,160 and 320mg vitamin B₁/kg diet) of vitamin B₁ were added to the basal diet.Each diet was fed to three replicate groups of E.sinensis(1.32±0.15 g) for 10 weeks.Results showed that survival rate,crude fat and ash content didn't have significant changes among Eriocheir sinensis fed different diet with different vitamin B₁content,but vitamin B₁ could significantly increase weight gain(WG),protein efficiency ratio(PER),crude protein content and hepatopancreas vitamin B₁ content,and decrease feed effeciency and water content.When the dietary vitamin B₁ reached to 80mg/kg treatment,WG and PER of the crab reached to a significant higher level than the other group(except 20mg/kg),and feed effeciency and water content of the crab reached to the lowest levels.Crab fed diets with 80 and 160mg/kg vitamin B₁ had a significant higher crude protein content than the crabs fed diets with 0,10 and 20mg/kg vitamin B₁.With the increase of dietary vitamin B₁,hepatopancreas amylase activity increased significantly,and the maximum amylase activitiy was observed in crab fed the 80 mg vitamin B₁/kg diet,and it was significantly higher than the crabs fed diets with 0,10,160 and 320 mg B₁/kg diet.The hepatopancreas lactate content had the opposite variation tendency with amylase activitiy.The maximum amylase activitiy was observed in crab fed the 80 mg vitamin B₁/kg diet,and it was significantly higher than the other groups.Brcken-line regression analysis showed that the optimum dietary thiamine requirement for obtaining maximum weight gain,hepatopancreas vitamin B₁ content and amylase activity of E.sinensis under these experimental conditions was 55.08-66.71mg vitamin B₁/kg diet.2.Dietary vitamin B₂ Requirement of junvenile Chinese mitten crab,Eriocheir sinensisThe objective of the study was to determine vitamin B₁ requirement of junvenile Chinese mitten crab,Eriocheir sinensis.The basal diet was formulated using vitamin B₂-free casein as the protein source.Eight graded levels(0,3,6,12,24,48 and 96mg vitamin B₂/kg diet)of vitamin B₂ were added to the basal diet.Each diet was fed to three replicate groups of E.sinensis(1.32±0.11g) for 10 weeks.Results showed that different dietary vitamin B₂ content didn't have significant effect on survival rate, feed effeciency,protein efficiency ratio,hepatopancreas vitamin B₂ content and water,ash and crude protein content.But with the increase of dietary vitamin B₂, weight gain of the crab increased first,and then decreased.Crabs fed 12 mg vitamin B₂/kg diet had a significantly higher weight gain than that fed 0,3,48 and 96mg vitamin B₂/kg diet.The crude fat content of crab had the opposite variation tendency, and the lowest crude protein content was observed in the crab fed diet with 12mg/kg vitamin B₂.Besides,the diet without vitamin B₂ could also inhibit the D-amino acid oxidase(DAAO) of hepatopancreas.Broken-line regression analysis showed that the optimum dietary pyridoxine requirement for maximum weight gain and hepatopancreas DAAO activity of E. sinensis under these experimental conditions was 8.25-10.02 mg pyridoxine/kg diet.3.Effect of dietary vitamin B₂ on the serum lipid and oxidation resistance capability of Chinese mitten crab,Eriocheir sinensis The objective of the study was to determine the effect of dietary vitamin B₂ on the oxidation resistance capability of Chinese mitten crab,Eriocheir sinensis.The basal diet was formulated using vitamin B₂-free casein as the protein source.Eight graded levels(0,3,6,12,24,48 and 96mg vitamin B₂/kg diet) of vitamin B₂ were added to the basal diet.Each diet was fed to triplicate groups of E.sinensis(1.32±0.11g) for 10 weeks.Results showed that serum triglyceride content didn't have significant change with the increase of dietary vitamin B₂ content,but serum cholesterol and LDL-C content decreased significantly with the increase of dietary vitamin B₂ content.Crabs fed 12,24,and 48 mg vitamin B₂/kg diet had a significant lower serum cholesterol content than the other group,and serum low density lipoprotein cholesterol(LDL-C) content also significant lower than the crabs fed 0,3, and 96mg vitamin B₂/kg diet.With the increase of dietary vitamin B₂ content, hepatopancreas glutathione reductase(GR) activity increased significantly.The maximum activity was observed in the crab fed diet with 12 vitamin B₂ mg/kg diet, and was significantly higher than the crabs fed with the other diets.4.Dietary vitamin B₆ requirement of junvenile Chinese mitten crab,Eriocheir sinensisThe objective of the study was to determine the dietary vitamin B₆ requirement of Chinese mitten crab,Eriocheir sinensis,in a ten-week feeding trial.The basal diet was formulated using vitamin B₆-free casein as the protein source.Eight graded levels (0,10,30,60,100,150,200and 400mg vitamin B₆/kg diet) of vitamin B₆ were added to the basal diet yielding final vitamin B6 contents of 8.31,25.56,34.43,70.02,111.70, 160.47,219.72 and 419.27mg/kg,respectively.Each diet was fed to three replicate groups of E.sinensis(2.12±0.56 g) for 10 weeks.Results showed that there were no significant differences in survival,weight gain,and the content of water and ash between crabs fed different diets.But protein utilization ratio(PUR) increased significantly with the increase of dietary vitamin B₆.The hightest PUR was found in crabs fed diet with 100mg vitamin B₆/kg diet,followed by crabs fed the diets with 60, 150,200,30,10,and 400 mg vitamin B₆/kg diet,and finally the control group. Patterns of the content of crude protein and crude fat were similar to that of PUR. With the increase of dietary vitamin B₆,both of them increased first,and then decreased.Crabs fed 100mg vitamin B₆/kg diet had a significantly higher protein and fat content than that fed 0 and 400mg vitamin B₆/kg diet.Besides,different dietary vitamin B₆ content also had significant effect on the activities of hepatopancreas glutama(?)e pyruvate transaminase(ALT) and glutamate aspartate transaminase(AST). They both increased with the increase of dietary vitamin B₆.The maximum hepatopancreas ALT activitiy was observed in crab fed the 100 mg vitamin B₆/kg diet, and it was significantly higher than all of the other groups.Combined,results in this study indicated that through stimulating the activity of transaminase,vitamin B₆ could assist the anabolism of protein,and then improved the accumulation of body protein and fat in crabs.Broken-line regression analysis showed that the optimum dietary pyridoxine requirement for maximum PUR and hepatopancreas ALT activity of E.sinensis under these experimental conditions was 81.675-85.74 mg pyridoxine/kg diet.