Antioxidant Responses,Neurotoxicity, and Metallothionein Gene Expression in Juvenile Korean Rockfish Sebastes schlegelii under Dietary Lead Exposure

Abstract

This study was conducted to assess toxic effects of dietary lead (Pb) exposure on Korean Rockfish Sebastes schlegelii. Juvenile rockfish were used to evaluate the oxidative stress, neurotoxicity, and metallothionein (MT) gene expression after dietary exposure to lead (as Pb²⁺; 0, 30, 60, 120 and 240 mg/kg). Superoxide dismutase (SOD) activity, a measure of oxidative stress, was substantially elevated in the livers and gills of fish given dietary Pb greater than 60 mg/kg. Glutathione S-transferase (GST) activity in the liver and gill was significantly increased by dietary Pb > 60 mg/kg. A significant decrease in glutathione (GSH) level was observed in fish liver after exposure to dietary Pb > 30 mg/kg and in the gill after treatment with dietary Pb > 120 mg/kg. Acecyltholinesterase (AChE) was noticeably decreased in the brain by dietary Pb > 120 mg/kg and in the muscle by dietary Pb > 60 mg/kg. Metallothionein gene expression in the liver was stimulated significantly by the Pb exposure. Because dietary Pb exposure had a toxic effect on antioxidant responses, a neurotransmitter, and a specific immune expression in rockfish, the results of this study can be used to determine potential useful markers of Pb toxicity.

Received June 11, 2016; accepted March 10, 2017 Published online May 3, 2017     

Influence of Ascorbic Acid and Glutathione Antioxidants on Frozen-Thawed Canine Semen

Poor sperm viability post-thaw has resulted in constant research into methods of cryopreservation of canine semen. One factor that may be involved in poor viability is sperm oxidative stress caused by excessive formation of reactive oxygen species. The present study was performed in order to evaluate the effect of different concentrations of ascorbic acid (AA) and glutathione (Glu) added to an extender for the freeze-thawing of dog sperm. Semen from five mature dogs was collected and frozen in two studies. Prior to and after freezing, sperm motility, morphology and membrane status were examined. In addition, sperm motility was examined up to 120 min after thawing to evaluate thermo-resistance. In study I, semen was collected twice from each dog. On both occasions, semen was divided into three aliquots: control, Glu 1 m m and Glu 5 m m . In study II, semen was collected twice and divided into three aliquots; control, AA 50 μ m and AA 250 μ m . Initial sperm motility was significantly higher in sperm diluted with AA 50 μ m ; sperm longevity, however, measured by a thermal-resistance test (TRT), was higher for Glu treatments. Higher concentration of Glu produced significant improvement in TRT and membrane status, whereas higher concentration of AA had a negative impact in sperm longevity. Antioxidant supplementation to semen freezing extenders improved semen quality post-thaw. Moreover, Glu had the most beneficial effect when supplemented at 5 m m .     

An Elevated Dietary Level of Ascorbic Acid Fails to Influence the Response of Anterior Kidney Neutrophils to Edwardsiella ictaluri in Channel Catfish

Abstract

Channel catfish Ictalurus punctatus (weight, 320–420 g) were fed diets with 100 or 1,000 mg ascorbic acid/kg of diet for 7 weeks in ponds. Anterior kidney neutrophil function was assessed by incubating the neutrophils with Edwardsiella ictaluri. Percent phagocytosis, phagocytic index (the mean number of bacteria phagocytized per cell by all neutrophils, including nonphagocytic ones), and bactericidal capabilities of the anterior kidney neutrophils were measured at 0, 90, 180, 270, and 360 min. Serum cortisol was also measured. No significant difference was observed between the two diets with respect to anterior kidney neutrophil function or serum cortisol levels. However, serum cortisol levels did affect mean phagocytic index of anterior kidney neutrophils. Catfish that had serum cortisol levels greater than 10 μg/dL displayed a significant decrease in the phagocytic index when compared with catfish that had cortisol levels less than 5 μg/dL.     

饲料中不同亚麻酸/亚油酸比对凡纳滨对虾幼虾生长性能和脂肪酸组成的影响

本试验旨在研究饲料中不同亚麻酸(C18:3n-3)/亚油酸(C18:2n-6)比对凡纳滨对虾(Litopenaeus van-namei)幼虾生长性能和脂肪酸组成的影响.采用鱼油、亚麻油和豆油作为脂肪源,以不同的比例配制4种粗脂肪水平约为7.2%的等氮饲料,饲料中C18:3n-3/C18:2n-6比值为0.17、0.30、0.56和0.68.选用平均体重为(0.573±0.002)g的凡纳滨对虾幼虾480尾,随机分为4组(每组3个重复.每个重复40尾虾),分别记为L0.17、L0.30、L0.56和L0.68.试验期为8周.结果显示,随着饲料中C18:3n-3/C18:2n-6比的升高,凡纳滨对虾幼虾增重率呈现先升高后降低的趋势,而饲料系数则呈现先下降后上升的趋势,但组间的差异均不显著(P>0.05).通过二元回归分析得出增重率(y)与C18:3n-3/C18:2n-6比(x)的关系为Y=-1 333.2x2+1 175.5x+785.66(R2=0.723 8),并得出当C18:3n-3/C18:2n-6比为0.44时,增重率最高.全虾粗蛋白质含量以L0.68组为最高,显著高于其他3组(P<0.05).全虾水分和粗脂肪含量以及肝胰指数组间差异均不显著(P>0.05).各组对虾肌肉中C18:2n-6和C18:3n-3含量低于它们在肝胰腺中的含量,而C20:4n-6,C20:5n-3(EPA)、C22:6n-3(DHA)在肌肉中的含量高于其在肝胰腺中的含量.L0.68组肝胰腺EPA含量显著高于L0.30组(P<0.05),DHA含量显著高于其他3组(P<0.05).肌肉EPA、DHA含量以L0.30组最高,但组间差异不显著(P>0.05).由此得出,饲料中C18:3n-3/C18:2n-6比一定程度地影响凡纳滨对虾幼虾的生长性能,显著影响肝胰腺和肌肉中C18:3n-3和C18:2n-6系列脂肪酸的含量.以增重率作为判定指标,建议饲料中C18:3n-3/C18:2n-6比值为0.44.     

日粮中添加抗坏血酸和锌对高温下肉仔鸡生长的影响

120只21日龄Ross-Ⅰ肉仔鸡随机分为A、B、C、D组。D组为对照组,喂以标准日粮;A组在此基础上添加300ppm抗坏血酸(AA),B组加100ppm锌(Zn);C组加300PPm AA和100 ppmZn。舍温控制在32.2℃(7-19时)和30.0℃(19-7时)。试验共进行5周。结果,各组鸡增重和饲料效率的顺序为A→C→B→D。添加AA的仔鸡血清T3、T3/T4及GH高于对照组,而直肠温,冠温及呼吸率相反。本实验表明,日粮中添加AA能减轻高温所致的仔鸡甲状腺减小及功能低下,有利于维持仔鸡的正常生理机能,增强对高温的耐受性,促进高温下仔鸡的生长,补加锌的效果不明显。     

Effect of Dietary Vitamin E on Cortisol and Glucose Responses to Handling Stress in Juvenile Beluga Huso huso

Abstract

An 8-week feeding experiment was conducted to investigate the effect of dietary vitamin E on the physiological response to handling stress in juvenile beluga Huso huso. Fish were fed six experimental diets supplemented with 0, 25, 50, 100, 200, or 400 mg Dl-all-rac-α-tocopherol acetate/kg diet. At the end of the experiment, the fish in each tank were subjected to acute handling and air exposure stress. Cortisol and glucose were measured as the primary hormonal and secondary metabolic responses to the stressors, both before and 3 h after application of the stressors. The growth parameters and feed utilization rates were significantly lower in fish fed the diet not supplemented with vitamin E than in fish fed diets supplemented with vitamin E. Cortisol concentration was not affected by dietary treatment but glucose concentration was. Fish fed vitamin E at 0, 25, 100, and 400 mg/kg diet had higher concentrations of glucose than those fed vitamin E at 50 and 200 mg/kg. However, fish fed diets with 50 and 200 mg/kg exhibited higher growth rates. These results indicate that dietary vitamin E has some effect on plasma glucose but no effect on plasma cortisol. In general, when the stressors were applied to belugas, the glucose and cortisol responses were relatively low. This may be due to higher resistance and lower physiological responses to these types of stressors by this species or by chondrosteans in general.

Received January 10, 2011; accepted August 4, 2011     

Erythrocyte Osmotic Fragility and Hematological Responses of Horses Administered Ascorbic Acid and Exposed to Road Transportation

The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties.     

Dietary Amino Acid Responses of Mixed-Sex Broiler Chickens From Two to Four Kilograms

Two experiments were conducted to assess dietary amino acid density responses on mixed-sex broiler live performance, meat yields, and economics from 36 to 60 d. In experiment 1, broilers were fed a common feeding program to 35 d. Dietary treatments were high (H), moderate (M), and low (L) amino acid density from 36 to 47 d of age and H or L amino acid density from 48 to 60 d of age. Dietary treatments were high-high (HH), high-low (HL), moderate-low (ML), and low-low (LL) during a 60-d production period. In experiment 2, common diets were provided from 1 to 47 d of age. Dietary treatments were H, M, L, and suboptimum (S) amino acid density and fed from 48 to 60 d of age. In experiment 1, increasing dietary amino acid density to HH improved cumulative feed conversion (1 to 60 d) by 4 points over the ML- and LL-fed birds. Broilers provided the HH regimen had 0.6% more total breast meat yield than the LL-fed birds. In experiment 2, broilers fed the H feeding regimen lowered cumulative (1 to 60 d) feed conversion by 3, 5, and 6 points and reduced abdominal fat percentage by 0.28, 0.23, and 0.23%, respectively, compared with the M-, L-, and S-fed birds. Decreasing dietary amino acid density from H to S reduced total breast meat weight and yield by 47 g and 0.82%, respectively. In general, feeding HL (experiment 1) and H (experiment 2) diets increased gross feed margins over the other dietary treatments with diverse diet cost and meat price scenarios.     

硒与抗坏血酸的生理作用

用红外光谱法分析硒蛋白的分布状态及硒蛋白与有机化合物作用关系。为研究硒与抗坏血酸的生理作用提供合理信息数据,硒是人和动物不可缺少的一种稀有分散性元素,由于其在生物体中生理作用比较特殊,已成为国内外学者重要研究课题之一,尽管人们将大部分注意力集中于硒与其它元素的相互作用,但硒与有机化合物之间的相互作用还是相当重要的。     

共轭亚油酸对断奶仔猪生产性能和免疫功能的影响

试验选用 72头 (2 3± 2 )d的断奶仔猪 ,随机分为 4个处理组 ,分别添加 0 ,1% ,2 %和 3%的共轭亚油酸 (CLA) ,研究CLA对断奶仔猪生产性能和免疫功能的影响。结果表明 ,随CLA添加剂量的增加 ,全期日增重和日采食量呈二次曲线增加 (P <0 .0 5 ) ,饲料转化效率线性改善 (P <0 .0 5 ) ;在第 2 8d ,特异的卵清白蛋白抗体产生量呈二次曲线增加(P <0 .0 5 ) ;在试验第 14和 2 8d ,外周血淋巴细胞转化率呈二次曲线提高 (P <0 .0 5 )。本试验表明 ,CLA对断奶仔猪有改善生长性能和增强免疫功能的作用。综合生长性能与免疫反应考虑 ,CLA的最佳添加剂量为 2 %。     

日粮中添加不同水平壳聚糖对天山雪鹅生长性能和免疫器官的影响

本试验采用单因子试验设计,选用100只健康1日龄天山雪鹅,随机分为5组,以研究日粮中添加不同水平的壳聚糖（0、100、200、300、400 g/t）对天山雪鹅生长性能及免疫器官的影响。结果表明,添加不同水平壳聚糖对天山雪鹅平均日增重（average daily gain, ADG）的影响差异均不显著（P＞0.05）;添加300 g/t水平的壳聚糖料重比最低,可显著提高饲料利用率;试验组与对照组血清总蛋白与血清白蛋白水平差异显著（P＜0.05）,对血清球蛋白水平与对免疫器官的影响及盲肠内大肠杆菌的影响差异不显著（P＞0.05）。     

不同ω6/ω3多不饱和脂肪酸日粮对AA肉鸡脂多糖免疫应激的影响

选用90只AA肉鸡母雏,饲喂30∶1、20∶1、10∶1、5∶1、2.5∶1 5种不同的不饱和脂肪酸（PUFA）日粮到56日龄,进行大肠杆菌脂多糖（LPS）和生理盐水连续3 d注射应激,研究不同比例ω6/ω3 PUFA对免疫机能的影响。试验结果表明,不同比例ω6/ω3 PUFA对应激前后体增重、应激后第1 d和第7 d血清总蛋白（TP）和IgG含量没有显著影响(P>0.05),但对血清白蛋白（Alb）含量、应激后第1 d新城疫抗体滴度、第7 d血浆皮质酮含量有显著影响(P<0.05)。LPS应激和对照相比,除对体增重的影响达到显著水平（P<0.05）外,对其他性状的影响均未达到显著水平(P>0.05)。与应激后第1 d相比,应激后第7 d的皮质酮水平下降,白蛋白、总蛋白含量和IgG含量上升,表现出机体缓解应激的变化。因此,不同比例的ω6/ω3 PUFA日粮对机体体液免疫功能产生不同程度的影响,其中20∶1日粮的平均血清TP和Alb含量在5种日粮中最高,2.5∶1日粮的平均血清IgG含量和ND抗体水平在5种日粮中最高。但随着5种日粮ω6/ω3 PUFA比值的降低,日粮间缓解应激的作用没有呈现明显的变化趋势。     

三颗针提取物和γ-氨基丁酸对肉仔鸡生长性能及免疫性能的影响

本文旨在研究饲粮中添加三颗针提取物和γ -氨基丁酸对肉仔鸡生长性能、养分表观消化率和免疫性能的影响.试验选用1日龄健康爱拔益加(AA)肉仔鸡240只,随机分为4组,每组6个重复,每个重复10羽.采用单因子试验设计,4组分别为在玉米～豆粕型饲粮中添加0.20％三颗针提取物、0.01％γ-氨基丁酸、0.20％三颗针提取物+...     

饲料中维生素A水平对凡纳滨对虾生长、饲料利用、体组成成分及非特异性免疫反应的影响

本文旨在研究5种等氮等能饲料中,维生素A添加水平对凡纳滨对虾(Penaeus vannameiBoone)生长、饲料利用、体组成成分及非特异性免疫反应的影响。试验选用平均初始体重为(0.069±0.005)g的凡纳滨对虾450尾,随机分为5个处理组,每组90尾,每组设3个重复,每个重复30尾。试验采用单因素设计,以维生素A醋酸酯为维生素A源,用添加不同水平维生素A(添加量分别为0、18、365、4和72 mg/kg)的饲料喂养凡纳滨对虾,试验期11周。结果表明:在养殖前4周,饲料中添加维生素A显著促进凡纳滨对虾的生长(P<0.05),提高其对饲料利用效率(P<0.05),而对对虾的成活率不产生显著的影响(P>0.05);第11周的结果表明,饲料中添加维生素A并不能显著影响凡纳滨对虾的生长、饲料利用效率和成活率(P>0.05)。维生素A对对虾体脂肪、蛋白质含量的影响显著(P<0.05),对对虾体水分和灰分含量无显著影响(P>0.05)。维生素A对对虾血清中溶菌酶活力、酚氧化酶活力和血液红细胞数量的影响显著(P<0.05),饲料中未添加维生素A或过量添加(超过36 mg/kg)均导致血清中溶菌酶活力、酚氧化酶活力和血细胞总数显著下降(P<0.0 5),而对血清超氧化物歧化酶活力无显著影响(P>0.0 5)。用折线回归模型分析饲料维生素A添加量与对虾增重率的变化关系,表明在试验前4周,凡纳滨对虾饲料中维生素A的适宜添加量为2 2.5 0 mg/kg;1 1周试验期间,凡纳滨对虾饲料中维生素A适宜添加量为1 8 mg/kg;以溶菌酶、酚氧化酶活力为指标,凡纳滨对虾饲料中维生素A最适添加量为5 9.5 1 mg/kg。     

饲料脂肪源对大菱鲆幼鱼生长性能和肌肉脂肪酸组成的影响

以不同脂肪源配制成等氮等脂的7种试验饲料,对体重为(27.31±0.10)g的大菱鲆幼鱼进行40 d的饲养试验,旨在探讨饲料脂肪源对大菱鲆幼鱼生长性能和肌肉脂肪酸组成的影响。7种试验饲料的脂肪源分别为鱼油、豆油、菜籽油、花生油、猪油、鱼油+豆油(鱼油∶豆油=1∶1)和鱼油+豆油+猪油(鱼油∶豆油∶猪油=3∶4∶3)。每种饲料设3个重复,每个重复12尾鱼。结果表明:鱼油+豆油组的增重率和特定生长率显著高于鱼油组、豆油组和菜籽油组(P0.05),花生油组、猪油组和鱼油+豆油+猪油组的增重率和特定生长率则显著低于其他各组(P0.05)。饲料系数以鱼油+豆油组最低,猪油组最高。各组干物质和总磷表观消化率差异不显著(P0.05),猪油组和鱼油+豆油+猪油组的粗脂肪表观消化率显著低于其他各组(P0.05)。花生油组、鱼油+豆油组和豆油组的粗蛋白质表观消化率显著高于猪油组(P0.05)。摄食不同脂肪源饲料的大菱鲆幼鱼鱼体水分、粗脂肪和粗灰分含量差异不显著(P0.05)。猪油组鱼体粗蛋白质含量显著低于菜籽油组、花生油组和鱼油组(P0.05),其余各组间无显著差异(P0.05)。除C14∶0以外,各组大菱鲆肌肉中的脂肪酸含量和相应饲料中脂肪酸含量呈正相关。大菱鲆幼鱼肌肉中n-3多不饱和脂肪酸(PUFA)含量以鱼油组和鱼油+豆油组较高,而以花生油组和猪油组较低。结果提示:豆油和菜籽油是大菱鲆幼鱼饲料良好的脂肪源,鱼油和豆油按1∶1混合添加则能使大菱鲆幼鱼更好地生长。     

Nitrogen Retention and Plasma Amino Acid Responses in Mature Geldings Fed Three Dietary Concentrations of Lysine

Six mature Quarter Horse geldings (age, 11.5 ± 4.7 years; body weight [BW], 526 ± 9.2 kg) were used in a replicated 3 × 3 Latin square design to determine the effects of three dietary lysine (Lys) levels on nitrogen (N) retention and plasma amino acid (AA) concentrations. The geldings were fed a basal diet of concentrate and Bermuda grass hay supplemented with synthetic essential amino acids (EAA) to meet estimated requirements for EAA. Geldings were fed one of three dietary treatments: (1) a basal diet deficient in Lys (L−; 0.027 g of Lys•kg⁻¹ BW•d⁻¹); (2) a basal diet supplemented with synthetic Lys to meet National Research Council (NRC; 2007) requirements (L+; 0.036 g of Lys•kg⁻¹ BW•d⁻¹); or (3) a basal diet supplemented at twice the recommended Lys requirement (2 × L; 0.070 g Lys•kg⁻¹ BW•d⁻¹). Horses fed the 2 × L diet had higher N intakes (P = .0056) than horses fed either the L− or L+ diet. However N retention (P = .63) was not different between treatments. Plasma Lys was greater (P < .0001) in 2 × L than L− and L+ diets. Plasma threonine (Thr; P < .01), methionine (Met; P = .03), and total plasma non-EAA (P < .05) concentrations decreased as dietary Lys increased. These results suggest N retention is not a good response criterion for evaluating the AA requirements of mature horses. However, plasma AA data indicated more efficient use of Thr and Met when horses were fed dietary Lys in concentrations greater than the current requirement recommended by the Nutrient Requirements of Horses (National Research Council, 2007).     

日粮营养素对水产动物免疫机能的影晌

现代营养学证明,水产动物营养与免疫关系密切,营养因素在水产动物免疫方面有着不可忽视的作用.本文主要介绍了日粮中主要营养物质如蛋白质、脂肪、维生素及矿物质等对水产动物免疫机能的影响.     

日粮苏氨酸水平对蛋鸡免疫机能的影响

本试验以玉米-豆粕型为基础日粮,按0.49%、0.52%、0.55%、0.58%和0.61%梯度添加苏氨酸,即T1、T2、T3、T4和T5处理组,研究苏氨酸对蛋鸡体液免疫、细胞免疫以及非特异性免疫机能的影响。结果表明:第1次注射小牛血清白蛋白(BSA)后,血清BSA抗体滴度第7天达到峰值,第2次注射BSA后,第4天达到峰值,T3处理组血清BSA抗体显著高于T1处理组(P<0.05)。由趋势分析得出,当BSA抗体为极值点时,日粮苏氨酸供给量为0.56%～0.6%。日粮苏氨酸水平也影响淋巴细胞增殖转化率,趋势分析得出,当刀豆素(ConA)指数为极大值时,苏氨酸含量为0.54%;苏氨酸添加量与LPS指数呈现显著的二次曲线关系(P<0.05),当LPS指数为极大值时,苏氨酸含量为0.55%;说明日粮中苏氨酸含量为0.55%时能增强T淋巴细胞转化率和B淋巴细胞增殖转化能力,处理组T4溶菌酶含量最大。各处理组间溶菌酶含量没有显著差异(P>0.05)。本试验表明,日粮中添加0.54%～0.57%苏氨酸能够提高蛋鸡细胞免疫和体液免疫反应,增强机体的抗菌防御机能。