连翘提取物对肉仔鸡热应激下生长性能和抗氧化活性的影响

选用1日龄健康的爱拔益加肉公雏196只,平均体重为(38.8±1.3)g,研究连翘提取物(FSE)对热应激(32±1)℃环境下肉鸡生长性能和抗氧化能力的影响。将肉仔鸡随机分为3个处理,每个处理14个重复,每个重复6只鸡。日粮处理组,分别为空白对照组(NC),维生素C组(PC):基础日粮+维生素C200mg/kg;连翘提取物组(FSE):基础日粮+FSE100mg/kg。结果表明:试验前期各处理间生长性能没有显著性差异。试验后期FSE组与NC组相比日增重显著提高(P<0.05),并且饲料转化率提高。FSE组比NC组血液总抗氧化能力(TAOC)、超氧化物歧化酶(SOD)含量显著提高(P<0.05),而丙二醛(MDA)水平下降。从试验全期看FSE组比NC组肝脏SOD含量显著提高(P<0.05)。说明FSE通过清除自由基途径,缓解活性氧对肠黏膜的损伤,改善营养物质消化率和生长性能,FSE有望成为高效天然抗氧化剂。     

五味子提取物对AA肉仔鸡抗氧化功能的影响

选用五味子提取物作为饲料添加剂,通过测定35、56日龄肉仔鸡血清、心脏、肝脏和肾组织中总超氧化物歧化酶(T-SOD)活性,谷胱甘肽还原酶(GR)活性,总抗氧化能力(T-AOC)与丙二醛(MDA)含量,研究五味子提取物对AA肉仔鸡抗氧化指标的影响。采用单因子随机分组试验设计。结果表明:添加五味子提取物可显著提高35日龄肉仔鸡血清和肝脏、56日龄肉仔鸡肝脏和心脏SOD活性。添加五味子提取物可显著降低35日龄肉仔鸡血清MDA含量,0.2%五味子提取物可显著降低35日龄肉仔鸡心脏MDA含量(P<0.05),0.4%五味子提取物可显著降低56日龄肉仔鸡肝脏MDA含量(P<0.05)。添加五味子提取物可显著提高35日龄血清和肝脏GR活性(P<0.05),并且作用效果好于黄霉素组,添加0.2%五味子提取物可提高56日龄肝脏和肾脏GR活性(P<0.05),并且作用效果好于黄霉素组。添加0.2%、0.4%五味子提取物组可显著提高35日龄肉仔鸡肾脏总抗氧化能力(P<0.05),添加五味子提取物可显著提高56日龄心脏总抗氧化能力(P<0.05)。     

桔梗多糖提取物对肉仔鸡抗氧化性能的影响

试验旨在探讨桔梗多糖提取物对肉仔鸡抗氧化性能的影响,挑选1日龄出生体重相近的1日龄AA肉鸡180只,采用单因子设计,随机分成3组.空白对照组饲喂基础日粮,试验1组、试验2组分别饲喂在基础日粮上添加1000ppm、1500ppm桔梗多糖提取物的日粮.试验结果表明,日粮里添加桔梗多糖提取物提高了肉仔鸡血清和肝脏中SOD活性,降低了血清和肝脏中MDA的含量,从而提高肉仔鸡的抗氧化能力,日粮中添加1000ppm-1500PPm桔梗多糖提取物效果较好.     

不同湿度和氨水平对肉仔鸡抗氧化性能及肉品质的影响

本研究旨在探讨鸡舍内不同湿度和氨浓度对肉仔鸡机体抗氧化性能和肉品质的影响.试验选用健康、体质量相近的21日龄AA雄性肉仔鸡192只,随机分为2组.一组为高氨组(暴露于70 mg·kg-1氨气,H),另一组是低氨组(暴露于30 mg·kg-1氨气,L).其中每一组的一半分别置于60％湿度(对照组,C),另一半置于35％湿度(处理组,T),这样组成4个试验组,对照1:60％湿度+30 mg·kg-1氨水平组(C+L)、对照2:60%湿度+70 mg·kg-1氨水平组(C+H)、处理1:35％湿度+30 mg·kg-1氨水平组(T+L),以及处理2:35％湿度+70 mg· kg-1氨水平组(T+H),试验期21 d.试验结束时测定肉仔鸡生产性能,血液及肌肉抗氧化性能和肉品质相关指标.试验结果表明,高氨(70 mg· kg-1)水平显著降低肉仔鸡结束体质量,平均日采食量,日增体质量,血液及肌肉中总抗氧化力及肉仔鸡宰后45 min时的胸肌a*值(P＜0.05);增加了胸肌存放5d时硫代巴比妥酸反应物水平(TBARS)含量,胸肌滴水损失率,宰后45 min时的胸肌b*值(P＜0.05)和L*值(P=0.054)及肌肉剪切力(P=0.075).低湿(35％相对湿度)处理降低了肉仔鸡试验结束体质量(P＜0.05),平均日采食量(P＜0.05)及平均日增体质量(P=0.072),胸肌中超氧化物歧化酶及谷胱甘肽过氧化物酶活性(P＜0.05)及宰后45 min时的胸肌L*值(P=0.053);增加了肌肉剪切力(P=0.057)和胸肌存放5及7d时的TBARS含量(P＜0.05).与低氨对照组(C+L)相比,高氨低湿组处理组(T+H)肉仔鸡的试验结束体质量、平均日采食量、平均日增体质量、血清总抗氧化力、胸肌中总超氧化物歧化酶及谷胱甘肽过氧化物酶活性,胸肌宰后45 min a*值均显著降低(P＜0.05),而宰后5及7d肌肉中TBARS含量、肌肉中滴水损失及肌肉剪切力均显著提高(P＜0.05).本研究结果揭示肉仔鸡舍内高氨(70 mg·kg-1)及低湿度均显著降低了肉仔鸡生产性能、机体抗氧化能力及肌肉品质,且低湿度环境加剧了高氨的不良影响.     

日粮中添加谷氨酰胺对肉仔鸡肉品质和抗氧化指标的影响

本试验旨在研究外源添加谷氨酰胺(Gln)对肉仔鸡肉品质的影响,并对肌肉中风味物质和抗氧化指标进行分析,探讨其对肉质的影响机理.选用1日龄艾维茵肉仔鸡360羽,随机分成4组(每组6个重复,每个重复15羽),对照组饲喂基础日粮,试验组饲喂在基础日粮中分别添加了0.5%、1.0%、1.5%谷氨酰胺的试验日粮.于42日龄进行屠宰取样,测定各项指标.结果表明,与对照组相比,各试验组鸡的肌肉系水力和pH均有所提高(P>0.05),皮脂厚和肌间脂肪宽度有所降低(P>0.05);肌肉中胶原蛋白含量显著增加(P<0.05);胸肌中必需氨基酸和鲜味氨基酸含量都显著增加(P<0.05),谷氨酸和苯丙氨酸含量亦显著增加(P<0.05);1.0%和1.5%添加组肌苷酸含量有所提高(P>0.05);1.0%Gln组胸肌中丙二醛(MDA)含量显著降低(P<0.05),各试验组胸肌中超氧化物歧化酶(SOD)活力有升高的趋势(P>0.05);0.5%和1.0%Gln组血清中SOD和谷胱甘肽过氧化物酶(GSH-Px)活力显著提高(P<0.05).以上表明,日粮添加Gln可改善肉仔鸡肉品质,提高鸡肉的鲜味和抗氧化能力,以0.5%的Gln添加量效果最佳.     

有机镁对肉仔鸡机体组织抗氧化机能及肉品质的影响

镁是动物生长发育及维持正常生理机能所必需的常量矿物质元素，参与体内能量代谢，催化或激活多种酶，特别是一系列的ATP酶。据D’Souza(1988)报道，在猪日粮中额外添加天冬氨酸镁，提高了猪抗应激的能力，减少了劣质肉的产生。基于此，本试验旨在研究有机镁对高温条件下肉仔鸡抗氧化机能和肉品质的影响。     

纳米氧化锌对肉仔鸡抗氧化性能的影响

本试验旨在研究纳米氧化锌对肉仔鸡抗氧化性能的影响.选用1日龄爱拔益加肉仔鸡192只,随机分为4个组,每个组4个重复,每个重复12只鸡.以添加硫酸锌(含锌80 mg/kg)的口粮为对照组,即A组,添加含锌40、80、120 mg/kg的3个纳米氧化锌水平组为试验组,即B、C、D组,试验期6周.试验结果表明:40 mg/kg锌添加水平的纳米氧化锌组能够显著提高(21、42 d)肉仔鸡血清中谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05、P<0.01),极显著提高(21、42 d)血清中总抗氧化能力(T-AOC)(P<0.01、P<0.01),减少(21 d)血清中一氧化氮(NO)生成(P<0.05).80 mg/kg锌添加水平的纳米氧化锌组能够极显著提高(42 d)肉仔鸡血清中GSH-Px活性(P<0.01),显著提高(42 d)肝组织中过氧化氢酶(CAT)和T-AOC活性(P<0.05、P<0.01),极显著提高(21 d)血清中T-AOC(P<0.01),减少(21、42 d)血清中NO生成(P<0.05、P<0.01),并能提高(42 d)血清抑制羟自由基能力(P<0.05),提高(21 d)肝组织中抗超氧阴离子自由基活性(P<0.05).由此可知,日粮添加纳米氧化锌可在一定程度上提高肉仔鸡机体的抗氧化性能,增强抗氧化酶活性,降低自由基的产生,以40、80 mg/kg添加量效果较佳.     

银杏叶提取物对肉仔鸡血脂、蛋白质水平和抗氧化功能的影响

试验旨在研究银杏叶提取物(EGB)对肉仔鸡血脂、蛋白质水平和抗氧化功能的影响。试验选用360只1日龄健康AA肉用母雏,随机分成5组,每组6个重复,分别饲喂添加0、0.15%、0.20%、0.25%EGB或90 mg/kg金霉素的玉米-豆粕型日粮。试验期为42 d。结果表明:添加0.20%、0.25%EGB可显著降低21日龄和42日龄肉仔鸡血清总胆固醇、甘油三酯和低密度脂蛋白胆固醇含量(P<0.05);显著提高血清球蛋白水平、血清过氧化氢酶和谷胱甘肽过氧化物酶活性(P<0.05),显著降低血清丙二醛含量(P<0.05),并且作用效果明显好于金霉素组(P<0.05)。另外,EGB使肉仔鸡血清总蛋白含量、总超氧化物歧化酶活性呈增加趋势。本试验表明日粮中添加0.20%、0.25%EGB可降低肉仔鸡血脂含量、提高血清球蛋白水平和抗氧化能力。     

热应激对肉仔鸡肉品质及抗氧化能力的影响

为探讨热应激对AA肉仔鸡肉品质及抗氧化能力的影响,试验选用35日龄体重相近的健康AA肉仔鸡（公）120只,随机分成2组,一组高温组（34℃）,一组为适温组（21℃）,每组5个重复,每个重复12只。试验期为7 d。结果表明：高温应激组胸肌和腿肌pH值显著低于适温对照组（P ＜0.05）,滴水损失显著高于适温对照组（P ＜0.05）,但两试验组间剪切力无显著差异（P＞0.05）。高温应激组胸肌超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性均低于对照组,且差异显著（P＜0.05）;GSH-Px活性两试验组间无显著差异（P＞0.05）。同时与对照组比较,高温可显著降低腿肌SOD、CAT和GSH-Px活性（P＜0.05）。高温应激组胸肌和腿肌MDA水平显著高于对照组（P＜0.05）。由此可见,热应激可使AA肉鸡肉品质下降,肌肉氧化程度增加,抗氧化能力降低。     

Forsythia suspensa extract attenuates lipopolysaccharide‐induced inflammatory liver injury in rats via promoting antioxidant defense mechanisms

Reactive oxygen species (ROS) have been shown to have a role in inflammation. We investigated whether Forsythia suspensa extract (FSE) could exert its antioxidant potential against lipopolysaccharide (LPS)‐induced inflammatory liver injury in rats. Rats were orally fed FSE once daily for 7 consecutive days prior to LPS (Escherichia coli, serotype O55:B5) injection. LPS treatment caused liver dysfunction as evidenced by massive histopathological changes and increased serum alanine aminotransferase and aspartate aminotransferase activities which were ameliorated by FSE pretreatment. FSE attenuated LPS‐induced depletion of cytosolic nuclear factor‐erythroid 2‐related factor 2 (Nrf2) and suppression of Nrf2 nuclear translocation in liver, and the generation of ROS and malondialdehyde in serum and liver. FSE increased the Nrf2‐mediated induction of heme oxygenase‐1 in liver, as well as superoxide dismutase and glutathione peroxidase activities in serum and liver. Importantly, FSE attenuated LPS‐induced nuclear factor‐кB (NF‐кB) nuclear translocation in liver, and subsequently decreased tumor necrosis factor‐α, interleukin (IL)‐1β and IL‐6 levels in serum and liver, which were associated with FSE‐induced activation of Nrf2 in liver. These results indicate that the protective mechanisms of FSE may be involved in the attenuation of oxidative stress and the inhibition of the NF‐кB‐mediated inflammatory response by modulating the Nrf2‐mediated antioxidant response against LPS‐induced inflammatory liver injury.     

The effect of dietary turmeric on antioxidant properties of thigh meat in broiler chickens after slaughter

Two hundred and fifty‐day‐old male broiler chicks (Ross 308) were used to investigate the dietary supplementation effects of different levels of 0.0 turmeric rhizome powder (TRP) (free TRP, F.TRP), 0.25 (low TRP, L.TRP), 0.5 (medium TRP, M.TRP) and 0.75% TRP (high TRP, H.TRP) or 50 mg/kg vitamin E (VE) on antioxidant properties of thigh meat in broiler chickens after slaughter. No effect of treatment was observed for the activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) and total antioxidant status (TAS) in thigh meat (P > 0.05) but all were reduced over time (P < 0.0001). A significant treatment*time interaction was observed for thigh meat GPX activity (P = 0.02). Significant effects of treatment and time were observed for malondialdehyde (MDA) content (P < 0.05). There was no significant difference between the treatments for thigh meat MDA content at slaughter (P > 0.05). Three days after refrigerator storage, MDA content in thigh meat of M.TRP birds was lower than that of F.TRP birds (P < 0.05). Both the M.TRP and VE birds showed a lower MDA content in thigh meat as compared with F.TRP birds 7 days after storage (P < 0.05). In conclusion, dietary consumption of 5 mg/kg TRP can increases the thigh meat shelf‐life storage and quality in broiler chickens after slaughter.     

Comparison of calpain and calpastatin activities in skeletal muscle of broiler and layer chickens

1. The objective of this study was to estimate the difference between broiler and layer chicks in the activities of calpain and calpastatin (inhibitor of calpain) in breast muscle. Differences between broilers and layers in body weight, daily gain at 3 weeks of age and fractional growth rate (FGR) during 2 and 3 weeks of age were statistically significant (P < 0.01).

2. Calpain and calpastatin activities were measured at three weeks of age with alkali‐denatured casein as a substrate. The m‐calpain (calpain activated by millimolar calcium concentration) activities in units/g muscle and units/ mg extractable muscle protein were 0.779 and 0.353 for broilers, and 1.042 and 0.440 for layers, respectively. The calpastatin activities in units/g muscle and units/mg extractable muscle protein were 0.332 and 0.153 for broilers, and 0.262 and 0.112 for layers, respectively.

3. Broilers with high FGR showed low m‐calpain and high calpastatin activities. In contrast, layers with low FGR showed high m‐calpain and low calpastatin activities.

4. These results suggest that m‐calpain and calpastatin activities in skeletal muscle vary between breeds which have different rates of muscle production.     

The effect of continuous ultraviolet irradiation on broiler chickens.

1.Continuous ultraviolet irradiation (10.45 muW/cm2) did not affect the growth or food conversion efficiency of broilers. 2. The cornea of the eye was roughened by the treatment and there was a loss of the regular arrangement of the corneal cells: vision was not significantly affected after 49 d exposure.     

The value of plant extracts with antioxidant activity in attenuating coccidiosis in broiler chickens

Coccidiosis remains one of the most important diseases in the poultry industry and results in the annual loss of millions of US dollars by the poultry industry. In South Africa and other developing countries where a large percentage of the population is unemployed, cheap food production is necessary. If the control of the coccidian parasite could be made more economical, these savings could be passed on to the consumer. In Europe, where the economics are different, people are becoming more aware of the potential dangers of using antimicrobials in producing animal protein. A solution to both these problems could be the use of plant products that function by mechanisms other than those of chemotherapeutics, with the additional advantage of a natural origin. Antioxidant compounds could hold promise for the control of Eimeria infections due to the association of coccidial infection with lipid peroxidation of the intestinal mucosa. Four plant extracts with antioxidant activity were screened for their anticoccidial activity in vivo with toltrazuril as the positive control. Combretum woodii (160 mg/kg) proved to be extremely toxic to the birds, while treatment with Tulbaghia violacea (35 g/kg), Vitis vinifera (75 mg/kg) and Artemisia afra (150 mg/kg) resulted in feed conversion ratios similar to toltrazuril, and higher than the untreated control. T. violacea also significantly decreased the oocyst production in the birds. From this study we conclude that antioxidant-rich plant extracts have potential benefits in treating coccidial infections. The promising results obtained with T. violacea justify further studies on the potential value of the plant as a therapeutic or prophylactic anticoccidial agent.     

不同抗氧化剂和添加水平对肉仔鸡生产性能和抗氧化性影响的研究

为了研究不同抗氧化剂产品和添加水平对肉仔鸡生产性能和抗氧化性能的影响,本研究选用1日龄爱拔益加(AA)肉仔鸡96只,随机分为3个处理,每个处理4个重复,每个重复8只鸡。对照组(CTR)饲喂不添加任何抗氧化剂的基础日粮;SQM6组饲喂基础日粮+48mg/kgSQM6;SQMax组饲喂基础日粮+80mg/kgSQMax。记录肉仔鸡的日均采食量和平均日增重,并于28日龄时,随机在每个重复中选取1只鸡进行翅静脉采血,测定血清抗氧化指标。研究结果表明:与CTR相比,肉仔鸡日粮中添加抗氧化剂有改善饲料转化率的趋势(P>0.05);添加SQM6显著提高了血清中超氧化物歧化酶(SOD)的活性(P<0.05),并显著降低了丙二醛(MDA)的含量(P<0.05);日粮中添加SQMax显著提高了肉仔鸡血清超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05)。以上结果表明,肉仔鸡日粮中添加抗氧化剂SQM6和SQMax能够提高血清中超氧化物歧化酶和谷胱甘肽过氧化物酶活性,降低丙二醛含量,改善肉仔鸡机体抗氧化功能。     

Effect of Forsythia suspensa extract and chito‐oligosaccharide alone or in combination on performance,intestinal barrier function,antioxidant capacity and immune characteristics of weaned piglets

We investigated the effects of Forsythia suspensa extract (FSE) and chito‐oligosaccharide (COS), alone or together, on performance and health status of weaned piglets. The treatments included a basal diet and three diets with 160 mg/kg COS, 100 mg/kg FSE, or 100 mg/kg FSE and 160 mg/kg COS. Supplementation with COS or FSE alone improved (P < 0.01) average daily gain and feed conversion ratio compared with the basal diet in the first 2 weeks. On day 14, COS or FSE supplementation separately produced stronger (P < 0.01) serum total antioxidant capacity and glutathione peroxidase activities and lower serum endotoxin (P < 0.05) and malondialdehyde (P < 0.01) concentrations, generated higher (P < 0.01) serum complement 4 concentration, peripheral blood lymphocyte proliferation and serum‐specific ovalbumin antibody level than the basal diet. No differences in oxidative injury and immunity indices were detected on day 28. The combined FSE and COS produced similar results compared with FSE or COS when given alone. These data indicate FSE or COS can increase performance by modulating intestinal permeability, antioxidant status and immune function in younger pigs. There appears to be similar advantage in feeding the additives in combination over those obtained from feeding them separately.