有机硒和维生素E对寿隐杂交鸡抗热应激性能的影响

通过向日粮中添加不同水平有机硒(0,0.15mg/kg)和维生素E(10,30,100IU/kg),测定热应激不同阶段试验鸡肝脏、肾脏及血清中丙二醛(MDA)含量、谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)活性。结果表明,日粮中添加有机硒和维生素E可明显降低肝脏、肾脏及血清中MDA的含量(P<0.05),提高GSH-Px活性,增强机体的抗氧化能力,提高试验鸡的抗热应激性能。     

维生素E在应激敏感猪的应用

应激敏感猪血浆中的肌酶和氧化基团的活性增高,这反映了抗氧化能力发生异常。日粮中添加维生素E则可降低对细胞膜的损害。本文即讨论了维生素E对应激敏感猪及其免疫应答的影响。     

维生素E和维生素C对热应激时肉仔鸡某些血液生化指标的影响

主要研究日粮中不同水平的VE、VC对肉仔鸡某些血液生化指标的影响.结果表明在日粮中添加50 mg/kg VE、200 mg/kg VC或200mg/kg VE、50 mg/kg VC可显著提高热应激时肉仔鸡血清中γ-球蛋白值;在日粮中添加50 mg/kg VE、50 mg/kg VC对提高乳酸脱氢酶、碱性磷酸酶活性效果较好;热应激时添加VE、VC对肉仔鸡谷丙转氨酶活性的影响有待探讨.     

热应激与鸡营养因子维生素C

在养鸡生产中,由于热应激而引起的增重速度、饲料利用率和存活力的降低,其损失是巨大的。炎热环境可使鸡采食量减少,继而引起生长率下降。为此,国内外学者从营养方面作了较深入的研究,发现热应激与AA 鸡维生素 C 营养有密切关系,日粮添加维生素 C 有助于消除热应激对鸡的不利影响。本文就热应激与日粮添加维生素 C 对鸡热应激的调整问题作一概述。一、鸡热应激反应鸡适宜的环境区域比较狭窄,且随年龄或体重的变化而变异。例如,1日龄肉用雏     

维生素E和维生素C对热应激时肉仔鸡某些血液生化指标的影响

主要研究日粮中不同水平的VE、VC对肉仔鸡某些血液生化指标的影响。结果表明：在日粮中添加50mg/kg VE、200mg/kg VC或200mg/kg VE、50mg/kg VC可显著提高热应激时肉仔鸡血清中γ－球蛋白值；在日粮中添加50mg/kg VE、50mg/kg VC对提高乳酸脱氢酶、碱性磷酸酶活性效果较好；热应激时添加VE、VC对肉仔鸡谷丙转氨酶活性的影响有待探讨。     

维生素C缓解动物热应激机理的探讨

热应激给畜牧业生产造成一定的损失。维生素C对缓解动物热应激有一定作用。作者就动物热应激的机理、维生素C的生理功能及维生素C缓解热应激的机理进行综述。     

专题策划：缓解动物热应激——维生素E降低鸡热应激的研究进展

维生素E是家禽营养中一种重要的微量营养素,在家禽的不同生理阶段部起到了重要作用,尤其是热应激时。许多文献报道了热应激时期动物体内的维生素水平大大降低,因此,该时期添加维生素来抵抗热应激就有了理论依据。本文主要通过论述维生素E与热应激的关系采探讨怎样降低热应激对鸡的影响。     

维生素C缓解蛋鸡热应激研究及其应用

夏季高温会导致蛋鸡出现热应激,给生产造成一定的损失.维生素C是一种水溶性维生素,具有抗氧化活性,可保护处于热应激状态下的动物.文章综述了维生素C在高温下蛋鸡体内的作用以及在蛋鸡生产中的应用研究进展,旨在为维生素C在蛋鸡生产中的应用提供参考.     

维生素C和维生素E的抗鸡热应激作用

1　热应激对鸡的影响11　热应激　鸡作为恒温动物,仅在严格的环境温度范围内保持体温。10～32℃是鸡维持正常体温的环境温度范围,21～26℃是鸡生存的适宜环境温度,此时鸡用于维持体温所付出的代谢能最少;26～32℃是尚能维持正常体温的温度范围;高于32℃则是鸡生理功能趋于紊乱的温度范围,即出现热应激。12　鸡热应激时的组织、生理、生化及免疫反应121　呼吸频率提高,肺通气量加大,发生热喘息,ＣＯ2排出量增加,致使血液中ＣＯ2分压下降,ｐＨ值升高,严重时出现呼吸性碱中毒。122　心律加快,肝、肾、胃肠道血液流量相对减少,血钙、血钾、血磷…     

维生素E对冷应激雏鸡血清NO含量及GSH-Px活性的影响

用含不同水平维生素E的日粮饲喂慢性冷应激(12℃±1℃)条件下的雏鸡。通过检测雏鸡血清NO含量、谷胱甘肽过氧化物酶(GSH-Px)活性等指标,探索维生素E对其抗氧化功能的影响。结果表明,应用维生素E后冷应激雏鸡血清NO含量极明显下降(P<0.01)、GSH-Px活性极显著升高(P<0.01)。表明维生素E可使冷应激引起的雏鸡血清NO含量、GSH-Px活性明显发生变化,具有缓解应激促进抗氧化功能的作用。     

Influence of supplemental magnesium, tryptophan, vitamin C, and vitamin E on stress responses of pigs to vibration

Our objectives were to investigate and compare the effects of supplemental Mg, Trp, vitamin E (vit E), and vitamin C (vit C) on stress responses of pigs undergoing transport simulation. In this study, 126 pigs (25.1 +/- 4.4 kg BW) were allocated to one of the six following treatments: 1) negative control (no supplementation); 2) positive control (i.m. injection with 0.5 mg of carazolol/20 kg BW 12 h before vibration, beta-blocker); 3) Trp (additional amount of 6 g/kg of feed for 5 d, as-fed basis); 4) Mg (3 g/L drinking water for 2 d); 5) vit E (additional amount of 150 mg/kg of feed for 21 d, as-fed basis); 6) or vit C (additional amount of 300 mg/kg of feed for 21 d, as-fed basis). Pigs were treated in groups of three, and each treatment was replicated seven times. Feed and water intake were not different among treatments. Heart rate variables (mean, peak, and minimum heart rate, ventricular ectopic beats, and ST elevation of Channels A and B) and heart rate variability were registered from the night before vibration. Pigs were subjected to vibration in a transport simulator (8 Hz, 3 m/s) for 2 h and allowed to recover for 2 h. Generally, the positive control pigs had the lowest heart rate values (mean, peak, minimum heart rate, ST elevation of Channel A; P < 0.05), whereas Mg and Trp decreased ventricular ectopic beats and ST elevation of Channel B, respectively. The effect of vit C and E as vagal stimulators was clearly visible, whereas carazolol and Mg clearly blocked the sympathetic pathways of the autonomic nervous system. During vibration, the negative control pigs lay the least, and Mg pigs the most (P < 0.05). Salivary cortisol concentrations (taken before and after vibration and after recovery) showed that vit E pigs produced the least cortisol during stress periods. Intermediary metabolites (glucose, lactate, creatine kinase, and NEFA) were analyzed in plasma from blood taken before and after vibration. At the two sampling points, the vit E and Mg pigs had the lowest NEFA concentrations (P < 0.05), and the vit E pigs also had the lowest lactate concentrations before vibration. Urine samples were collected before and after vibration to determine catecholamine concentrations; only negative control pigs had an increase (P = 0.04) in epinephrine concentration, despite large individual variation. In general, these results indicate that the supplementation of Trp, Mg, vit E, or vit C improved coping ability of pigs during vibration comparison with the negative control treatment. A muscular injection of carazolol influenced only the heart rate variables.     

维生素E的生物学功能及在鸡生产中的应用

维生素E是动物机体内必需的一类脂溶性维生素,它具有抗氧化、抗应激、增强机体免疫力及繁殖力等生物学功能,在饲粮中添加适量的维生素E,能够有效地缓解鸡群应激反应、提高生产性能、改善繁殖性能等。本文就维生素E的生物学功能及在鸡生产中的应用进行综述,旨在为进一步研究维生素E在鸡生产中的应用提供理论指导及参考依据。     

鸡热应激与热应激蛋白的作用机理研究

高温导致畜禽热应激问题的危害正日益突出并倍受关注。针对这些问题本刊推出“热应激专栏”,目的是为缓解夏季普遍存在的畜禽热应激提供理论和技术支持,使从业者能通过一些技术手段来规避热应激带来的损失。由于时间的仓促,本期组织的稿件内容覆盖面不是很全,但是以后会陆续推出有关内容,希望大家能继续关注。同时我们也希望专家、学者能踊跃地发表真知灼见与广大读者分享,把热应激理论、防制调控推到一个更高的阶段。     

鸡热应激的危害及防治措施

我国大部分地区夏季炎热期达3个月之久，长江以南地区高温持续时间更长，严重影响鸡群的生长和生产性能，导致鸡群采食量减少，体重下降，肉仔鸡生长缓慢，蛋鸡产蛋率下降，给养鸡业带来重大经济损失。因此，在夏季必须重视鸡舍的防暑降温，加强饲养管理，并通过某些营养素的调节来改善热应激造成的鸡群生产性能的下降，确保鸡群能安全渡夏，从而提高鸡群在热应激状态下的经济效益。     

Meat quality of heat stress exposed broilers and effect of protein and vitamin E

1. This study was designed to determine the effects of heat stress exposure on broiler fattening performance, meat quality and microbial counts.

2. Six groups were established: CHP (24°C?+?210?g/kg crude protein (CP)), SHP (34°C?+?210?g/kg CP), CLP (24°C?+?190?g/kg CP), SLP (34°C?+?190?g/kg CP), SHPVE (34°C?+?210?g/kg CP?+?Vitamin E) and SLPVE (34°C?+?190?g/kg CP?+?Vitamin E) groups.

3. It was determined that the body weights of the male animals included in Group CHP displayed statistically significant differences in comparison to those of Groups SHP, CLP and SLP. Furthermore, it was ascertained that the values of Group CLP also displayed statistically significant differences in comparison to those of Groups CHP, SHP and SLP. The feed consumptions in Groups CHP and CLP were significantly different from those of the remaining groups, excluding Group SHP. The highest feed conversion rate was determined in Group SHPVE.

4. When evaluated for chicken drumstick TBA values, Group CHP differed significantly from Groups SHP, SHPVE, CLP and SLP, whilst Group CLP differed significantly from Groups SHP, SHPVE and SLP. On the other hand, when evaluated for breast meat TBA values, Group CHP displayed statistically significant differences in comparison to Groups SHP, SLP and SLPVE, whilst Group CLP differed significantly from Groups CHP, SHP, SLP and SLPVE.

5. The sensitivity of breast meat to colour susceptibility was greater than that of chicken drumsticks. While storage period affected the TBA values and microbial counts of meat significantly, its effect on colour parameters was found to be variable. Trial groups significantly affected total aerobic mesophilic bacteria counts in chicken drumsticks, and Enterobacteriaceae and total aerobic mesophilic bacteria counts in breast meat.

6. In conclusion, heat stress adversely affected final body weights and the lipid oxidation of meat, whilst vitamin E alleviated these adverse effects.     

Effects of vitamin C and vitamin E on performance, digestion of nutrients and carcass characteristics of Japanese quails reared under chronic heat stress (34 degrees C)

This study was conducted to determine the effects of vitamin C (L-ascorbic acid) and vitamin E (DL-alpha-Tocopheryl acetate) on performance, digestion of nutrients and carcass characteristics of Japanese quails reared under chronic heat stress (34 degrees C). A total of 180 10-day-old Japanese quails were randomly assigned to six treatment groups, three replicates of 10 birds each. The birds with a 2 x 3 factorial design received either two levels of vitamin C (100 and 200 mg/kg of diet) or three levels of vitamin E (125, 250, or 500 mg/kg of diet). Then, 200-mg vitamin C/kg of diet, compared with that of 100 mg/kg of diet, and higher dietary vitamin E inclusions resulted in a higher performance. The interaction between vitamin C and vitamin E for final body weight change (p=0.01) and feed efficiency (p=0.02) was detected. Final body weight change and feed efficiency increased to a higher extent by increasing dietary vitamin C when higher vitamin E levels were fed. Carcass characteristics improved with an increase of both dietary vitamin C and vitamin E (p=0.004). The interactions on carcass characteristics were all significant (p=0.02) and manifested themselves in a way that they were improved to a higher extent by an increase of dietary vitamin C when higher vitamin E levels were fed. Digestibility of nutrients (DM, OM, CP and EE) was greater with higher dietary vitamin C (p < 0.02) and also with higher vitamin E (p=0.07). There were no interactions detected for digestibility of nutrients (p=0.32). Taken together, the results of the present study conclude that a combination of 200 mg of vitamin C and 250 mg of vitamin E provides the greatest performance in Japanese quails reared under heat stress and can be considered as a protective management practice in poultry diet, alleviating the negative effects of heat stress.     

Effect of vitamin E and copper on the vitamin E status and performance of growing pigs

A 13-wk trial was conducted with 32 pigs to determine the effects of dietary Cu (250 ppm) and alpha-tocopheryl acetate (ATA, 22 IU/kg) on the performance, serum enzymes, serum and tissue tocopherols, and antibody production in growing pigs. Pigs were fed corn-soybean meal diets containing 21% CP the first 4 wk and 18% CP during the rest of the trial. All feed was stored a minimum of 14 d before it was fed. The addition of Cu decreased (P less than .01) the concentration of alpha-tocopherol in the feed. alpha-Tocopherol concentrations were less than .01 mg/kg in the starter diet and less than 2 mg/kg in the grower diet after 14 d of storage. Supplemental Cu or ATA had no effect on ADG, feed intake, or gain:feed during the first 4 wk. During wk 5 to 13, the addition of Cu to diets containing no ATA increased daily feed intake and decreased gain:feed, but with ATA addition, feed intake decreased and gain:feed increased, resulting in a Cu x ATA interaction (P less than .05). The addition of Cu or ATA had no effect (P greater than .1) on serum glutathione peroxidase or lactic dehydrogenase activity. Serum tocopherols were reduced (P less than .05) by the addition of Cu during wk 1 to 4, 6 (P less than .01), and 7 (P less than .05) and increased (P less than .01) by ATA addition during the entire experiment. The addition of ATA increased the tocopherol concentrations in bile, ham, heart, pancreas, kidney, spleen, liver, psoas and longissimus muscle (P less than .01), kidney fat, backfat, and adrenal gland (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)