Effects of dietary pyridoxine on disease resistance,immune responses and intestinal microflora in juvenile Jian carp (Cyprinus carpio var. Jian)

This experiment was conducted to evaluate the effects of dietary pyridoxine on disease resistance, immune responses and intestinal microflora of fish. A total of 1050 Jian carp (11.71 ± 0.05 g) were randomly distributed into seven groups, feeding diets containing graded levels of pyridoxine (0.2, 1.7, 3.2, 5.0, 6.3, 8.6 and 12.4 mg kg^?1 diet). After 80 days of feeding, a challenge trial was conducted by injection of Aeromonas hydrophila for 17 days. Results indicated that with increasing dietary pyridoxine concentration up to 5.0 mg kg^?1 diet, survival rate after challenge with A.hydrophila and phagocytic activity of leukocyte were improved (P < 0.05), and plateaued thereafter (P > 0.05). Red blood cell and white blood cell counts were lowest when fed the diet containing 1.7 mg pyridoxine kg^?1 diet. Haemagglutination titre, lysozyme activity, acid phosphatase activity, total iron‐binding capacity, antibody titre and immunoglobulin M content followed the similar pattern to that observed with survival rate. Aeromonas hydrophila, Escherichia coli and Lactobacillus counts in intestine were not affected by dietary pyridoxine concentration (P > 0.05). These results suggested that pyridoxine could enhance immune response of fish.     

The antioxidant status,apoptosis, intercellular integrity and immune function of grass carp (Ctenopharyngodon idella) head kidney and spleen fed different levels of pyridoxine

This study was carried out to investigate the effects of dietary pyridoxine (PN) on the antioxidant status, apoptosis, intercellular integrity and immune function of head kidney and spleen in young grass carp (Ctenopharyngodon idella). Results showed that compared with the optimal PN level, (a) PN deficiency decreased antioxidant enzyme activities and down‐regulated the mRNA levels of antioxidant enzymes, NF‐E2‐related factor 2 (Nrf2), myeloid cell leukaemia‐1 (Mcl‐1) and tight junction proteins, whereas it increased the contents of reactive oxygen species (ROS), malondialdehyde (MDA) and protein carbonyl (PC), and up‐regulated the mRNA levels of cysteinyl aspartic acid‐protease (caspase), Fas ligand (FasL), p38 mitogen‐activated protein kinase (p38MAPK) and myosin light chain kinase (MLCK) in the head kidney and spleen of fish (p < .05). (b) PN deficiency decreased lysozyme (LZ) and acid phosphatase (ACP) activities, and complement contents, and down‐regulated the mRNA levels of antibacterial peptides, anti‐inflammatory cytokines, inhibitor of κBα (IκBα) and target of rapamycin (TOR), whereas it up‐regulated the mRNA levels of pro‐inflammatory cytokines and nuclear factor kappa B p65 (NF‐κBp65) in the head kidney and spleen of fish (p < .05). (c) Dietary PN requirements of grass carp based on the malondialdehyde content and lysozyme activity were estimated as 4.97 and 4.99 mg/kg diet, respectively.     

Dietary thiamin and pyridoxine requirements of fingerling Indian major carp,Cirrhinus mrigala (Hamilton)

Two experiments were conducted to quantify the dietary thiamin (experiment I) and pyridoxine (experiment II) requirements of fingerling Cirrhinus mrigala for 16 weeks. In experiment I, dietary thiamin requirement was determined by feeding seven casein–gelatin‐based diets (400 g kg^?1 CP; 18.69 kJ g^?1 GE) with graded levels of thiamin (0, 0.5, 1, 2, 4, 8 and 16 mg kg^?1 diet) to triplicate groups of fish (6.15 ± 0.37 cm; 1.89 ± 0.12 g). Fish fed diet with 2 mg kg^?1 thiamin had highest specific growth rate (SGR), protein retention (PR), RNA/DNA ratio, haemoglobin (Hb), haematocrit (Hct), RBCs and best feed conversion ratio (FCR). However, highest liver thiamin concentration was recorded in fish fed 4 mg thiamin kg^?1 diet. Broken‐line analysis of SGR, PR and liver thiamin concentrations exhibited the thiamin requirement in the range of 1.79–3.34 mg kg^?1 diet (0.096–0.179 μg thiamin kJ^?1 gross energy). In experiment II, six casein–gelatin‐based diets (400 g kg^?1 CP; 18.69 kJ g^?1 GE) containing graded levels of pyridoxine (0, 2, 4, 6, 8 and 10 mg kg^?1 diet) were fed to triplicate groups of fish (6.35 ± 0.37 cm; 1.97 ± 0.12 g). Fish fed diet containing 6 mg kg^?1 pyridoxine showed best SGR, FCR, PR, RNA/DNA ratio, Hb, Hct and RBCs, whereas maximum liver pyridoxine concentration was recorded in fish fed 8 mg kg^?1 dietary pyridoxine. Broken‐line analysis of SGR, PR and liver pyridoxine concentrations reflected the pyridoxine requirement from 5.63 to 8.61 mg kg^?1 diet. Data generated during this study would be useful in formulating thiamin‐ and pyridoxine‐balanced feeds for the intensive culture of this fish.     

Pyridoxine induced neuropathy by subcutaneous administration in dogs

To construct a sensory neuropathy model, excess pyridoxine (150 mg/kg s.i.d.) was injected subcutaneously in dogs over a period of 7 days. During the administrations period, the dogs experienced body weight reduction and proprioceptive loss involving the hindquarters. After pyridoxine administration was completed, electrophysiological recordings showed that the M wave remained at a normal state, but the H-reflex of the treated dogs disappeared at 7 days. The dorsal funiculus of L₄ was disrupted irregularly in the axons and myelin with vacuolation. The dorsal root ganglia of L₄, and sciatic and tibial nerves showed degenerative changes and vacuolation. However, the lateral and ventral funiculi of L₄ showed a normal histopathologic pattern. Although this subcutaneous administration method did not cause systemic toxicity and effectively induced sensory neuropathy, this study confirmed the possibility of producing a pyridoxine-induced sensory neuropathy model in dogs with short-term administration.     

中国对虾对维生素B2、B5、B6营养需要的研究

研究了三种水溶性维生素Ｂ２，Ｂ５和Ｂ６在以酪蛋白为蛋白源的饲料中的不同含量对中国对虾的存活率，体重增重率，体长增长率，蛋白质消化率及实验维生素在体内的累积量等方面的影响。结果表明，在每１００ｇ饲料中维生素Ｂ２、Ｂ５和Ｂ６的含量分别在１０（体重１．５３ｇ）－２０ｍｇ（体重６．００ｇ）、４０ｍｇ、１４ｍｇ时，上述指标均达最佳，维生素缺乏或过量都会阻碍对虾生长，在适宜添加量范围中，随着饲料中维生素Ｂ６的     

Pyridoxine deficiency of grouper, <Emphasis Type="Italic">Epinephelus coioides</Emphasis>: physiological and biochemical alteration

Pyridoxine is essential for animals. The purpose of this study was to investigate the pyridoxine deficiency symptoms and the fit dose of pyridoxine to keep normal physiological function in grouper, Epinephelus coioides. Graded levels of pyridoxine (0, 1, 2, 4, 8, 16, 32 mg pyridoxine kg⁻¹ diet) were fed to grouper juveniles (14.83±0.31 g) for 8 weeks, and then some physiological and biochemical parameters were measured. Pyridoxine deficiency symptoms such as anorexia, poor survival, convulsion, helically swimming and hyperirritability were observed in fish fed the pyridoxine-deficient diet, and these fish also showed low whole blood haemoglobin level, liver glutamic-pyruvic transaminase (GPT) and superoxide dismutase (SOD) activities. Slight symptoms of pyridoxine deficiency also appeared among fish fed the diet with very low dose (1 mg pyridoxine kg⁻¹ diet) of pyridoxine in 6 weeks. Broken-line regression analysis showed that the optimal pyridoxine levels for these fish to keep normal survival, whole blood haemoglobin level, liver GPT and SOD activities were approximately 1.75, 1.87, 2.22 and 2.05 mg kg⁻¹, respectively.     

Effects of pyridoxine on antioxidative parameters in juvenile Jian carp (Cyprinus carpio var. Jian)

To investigate the effects of dietary pyridoxine (PN) on antioxidant status of fish in serum, intestine and trunk kidney, 1050 juvenile Jian carp (11.7 ± 0.1 g) were used for the experiment. The carp were divided into seven groups and fed diets containing graded levels of PN (0.20, 1.71, 3.23, 4.96, 6.32, 8.58 and 12.39 mg kg^?1 of diet) for 80 days. Results of the study showed that content of malondialdehyde in serum, intestine and kidney tissues was the highest when fed the diet containing 1.71 mg PN kg^?1 diet (P < 0.05). Meanwhile, the protein carbonyl content of intestine and kidney tissue showed a downward trend to a point (P < 0.05). Conversely, activities of superoxide dismutase, catalase, glutathione peroxidase (GSH‐Px), glutathione S‐transferase, glutathione reductase and glutathione (GSH) content in serum, intestine and kidney tissue were generally higher in PN‐supplemented diets than unsupplemented diet (P < 0.05). The present results indicated that the PN decreased lipid peroxidation and protein oxidation in fish, and partly because of its improved antioxidant enzymes activities and levels of GSH.     

Dietary pyridoxine promotes growth and cellular metabolic plasticity of Chanos chanos fingerlings exposed to endosulfan induced stress

An attempt was made to assess the effect of dietary pyridoxine supplementation on growth performance and cellular metabolic enzymes of Chanos chanos fingerlings under endosulfan induced stress. Two‐hundred and twenty‐five fish were randomly distributed into five treatments, each with three replicates and fed four isocaloric and isonitrogenous diets with graded levels of pyridoxine for 45 days. Endosulfan concentration in the water was maintained at sublethal level of 1/40th of 96 h LC₅₀ (0.52 ppb). Dietary pyridoxine supplementation significantly enhanced growth performance viz. weight gain (%), specific growth rate, feed conversion ratio and protein efficiency ratio of fish compared to control diet fed group. The results of this experiment revealed that the activities of digestive and metabolic enzymes were significantly improved after feeding with dietary pyridoxine supplementation in C. chanos. Significantly increased muscle and brain ascorbic acid content was observed in fish fed diets containing pyridoxine. Histological studies on liver of fish fed pyridoxine‐supplemented diet showed the normal architecture of hepatocytes compared to non‐pyridoxine fed group. The results obtained in this study revealed that the inclusion of pyridoxine in diet has a protective effect against endosulfan induced stress in C. chanos fingerlings through metabolic enzyme activities and vitamin C content. This study has a potential in ameliorating the toxic effect of endosulfan induced stress using dietary supplementation of pyridoxine.     

Dietary pyridoxine requirement of juvenile Jian carp (Cyprinus carpio var. Jian)

In a 80-day feeding trial, a total of 1050 juvenile Jian carp ( Cyprinus carpio var. Jian) with an average initial weight of 10.71 ± 0.05 g were fed semi-purified diets containing seven graded levels of pyridoxine (0.20, 1.71, 3.23, 4.96, 6.32, 8.58 and 12.39 mg pyridoxine kg⁻¹ diet). Results indicated that with increasing dietary pyridoxine levels up to 4.96 mg kg⁻¹ diet, percent weight gain (PWG) and specific growth rate (SGR) were improved, and no differences were found with further increase of pyridoxine levels. Feed intake also followed the similar pattern to that observed with PWG and SGR when dietary pyridoxine levels were ≤6.32 mg kg⁻¹ diet. But feed efficiency and protein efficiency ratio were not affected by pyridoxine levels. Crude protein of carcass, productive protein value and plasma ammonia concentration were improved with increasing dietary pyridoxine levels up to 4.96 mg kg⁻¹ diet. Amylase activities in the intestine were improved with increasing dietary pyridoxine levels up to 4.96 mg kg⁻¹ diet, but protease and lipase activities in the intestine were not affected by pyridoxine levels. Na⁺, K⁺-ATPase and Gamma-glutamyl transpeptidase activities in proximal intestine, mid intestine (MI) and distal intestine (DI) were lowest when fed the diet containing 1.71 mg pyridoxine kg⁻¹ diet. The alkaline phosphatase activities in MI and DI followed the same pattern. The dietary pyridoxine requirement of juvenile Jian carp based on PWG estimated by broken line model was 6.07 mg pyridoxine kg⁻¹ diet.     

军曹鱼幼鱼对吡哆醇的需要量

以初始体重(3.23±0.06)g的军曹鱼为研究对象,以酪蛋白(不含维生素)、明胶、鱼肉浓缩蛋白为蛋白源,在基础饲料中分别添加0、2、4、8、16和32mgPN/kg,配制出6种实验饲料,使饲料中吡哆醇的水平分别达到0.22、1.89、3.87、7.54、14.75和29.88mgPN/kg,研究军曹鱼对吡哆醇的需要量。养殖实验在室内流水系统中(250L)进行,每个处理设3个重复,每个重复放养军曹鱼25尾。养殖实验过程中,海水盐度为30～34,水温28～32℃,溶氧>7mg/L,养殖实验持续9周。实验结果显示,在0.22～3.87mgPN/kg水平范围内,随着饲料中吡哆醇含量的升高,实验鱼特定生长率显著升高,当饲料吡哆醇水平达到或高于3.87mg/kg时,各饲料组实验鱼的特定生长率(2.68～2.71%/d)无显著差异,而都显著高于0.22和1.89mg/kg饲料组的特定生长率(1.17～2.06%/d)P<0.05)。军曹鱼肝脏吡哆醇含量、吡哆醛含量、谷丙转氨酶活力、谷草转氨酶活力均与特定生长率有相似的变化趋势,即在3.87mg/kg饲料组接近或者达到最大值,在达到或超过3.87mg/kg时达到或近似达到一...