Effects Of Dietary Vitamin K On Digestive And Absorptive Function,Immune Function And Antioxidative Status Of Juvenile Jian Carp(Cyprinus Carpio Var. Jian)

This experiment was conducted to study the effects of dietary vitamin K levels on growth performance, digestive and absorptive function, immune function and antioxidant status of juvenile Jian carp(Cyprinus carpio var. Jian). A total of1400juvenile Jian carp (8.93±0.03g) were fed diets with six levels of vitamin K0.027(basal diet),1.522,3.015,4.511,6.018and7.519mg kg-1diet; and one basal diet contained the antibiotic sulfamidinum (11000mg kg-1diet) without vitamin K supplementation. Addition of this antibiotic was designed to suppress intestinal synthesis of vitamin K. After the feeding trial (60d),30fish with similar body weight obtained from each treatment to conduct a challenge trial (17d).Vitamin K deficiency syndrome-ulceration hemorrhage in the skin was observed in the present study. Percentage weight gain (PWG), special growth ratio (SGR), feed intake (FI), feed efficiency (FE), protein production value (PPV), lipid production value (LPV) and ash production value (APV) were improved by vitamin K (P<0.05). Correlation analysis showed that PWG has great significant positive correlation with FI and FE (r1=+0.985, P<0.01, r2=+0.963, P<0.01). Hepatopancreas weight (HW), hepatopancreas protein content (HPC), intestine length (IL), intestine weight (IW), intestine protein content (IPC), the activities of amylase (AMS), lipase (LPS), trypsin, chymotrypsin in the hepatopancreas and intestine, cholecystokinin (CCK) content in proximal intestine (PIS), creatinekinase (CK) activities, y-glutamyl transpeptidase (γ-GT), Na+, K+-ATPase and alkaline phosphatase (AKP) in PIS, mid intestine (MIS) and distal intestine (DIS) were increased with vitamin K supplement (P<0.05). The data showed that certain level of vitamin K increased the counts of intestinal Lactobacillus (LB), and decreased the counts of Escherichia coli (EC) and Aeromonas (P<0.05). The dietary vitamin K decreased the malondialdehyde (MDA) and protein carbonyl (PC) content in the serum, intestine, hepatopancreas, muscle, head kidney and spleen (P<0.05). The activities of anti-superoxide anion (ASA), anti-hydroxy radical (AHR), catalase (CAT), glutathione-iS-transferase (GST), glutathione reducase (GR), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione (GSH) content in the serum, intestine, muscle, hepatopancreas, head kidney and spleen were increased by vitamin K (P<0.05). Meanwhile, vitamin K improved survival rate, head kidney weight, spleen weight, erythrocytes and leukocyte count. T-AOC, addiment C3content, activities of lysozyme and IgM content in the serum, intestine, head kidney and spleen were increased with vitamin K supplement (P<0.05).In conclusion, vitamin K deficiency results in anorexia, poor growth and ulceration hemorrhage in the skin. Vitamin K promoted the growth and increased the FE of juvenile Jian carp, and the enhanced FE is correlated with the improved utilization of nutrition; vitamin K could enhanced the capacity of digestive enzymes synthesis and secretion, as well as absorptive ability by promoting the growth development of the hepatopancreas and intestine; vitamin K could optimize the intestinal microflora by increasing the counts of LB and decreasing the counts of EC and Aeromonas; vitamin K enhanced the growth of the hepatopancreas and intestine may partly due to the depressed lipid peroxidation and protein oxidative damage by vitamin K, and the improved enzymatic antioxidative and non-enzymatic antioxygen capability; meanwhile, vitamin K has the ability to improve the growth develepment of immune organ by improving the antioxidant abilities, and enhance the immunity ability of the serum, intestine, head kidney and spleen. The dietary vitamin K requirement of juvenile Jian carp (8.93-73.65g) based on PWG was3.15mg kg-1diet.