棉酚对家畜繁殖性能的影响

棉酚是棉籽中的一种芳香酚,由于分子中含有活泼的羟基和醛基,故能发生多种反应,生成半缩醛、酚酮类似物等。早在本世纪初已发现单胃动物采食过量的棉籽饲料会中毒,这与棉酚的毒性有关。许多研究表明,棉酚能够干扰各种单胃家畜的发情周期、妊娠以及胚胎的生长发育,一定剂量的棉酚能够导致雄性不育。反刍动物对棉酚的毒性耐受力虽较单胃动物强,但也会产生不利影响。     

棉籽饼饲料中棉酚生殖毒性的研究进展

棉籽饼作为一种优质、廉价的动物饲料蛋白得到广泛的应用。但是,棉籽饼中含有的棉酚在一定程度上限制了其使用量。动物长期采食含有棉酚的饲料易引起生殖毒性。对棉酚的理化性质、限量使用及其对动物生殖毒性的研究现状进行了综述。     

棉酚在肉禽体内的毒性和残留及其营养对策的研究进展

棉酚是棉籽饼粕含有的主要毒性物质,其对畜禽存在蓄积性毒性,在畜产品中残留量高,除了直接影响到动物生长性能外,也间接影响到人类健康。同时,棉酚也限制了棉籽饼粕在动物生产中的广泛应用。因此,本文拟对棉酚的结构与分类,棉酚对肉禽的毒性效应及其在禽体内的残留与消除规律、营养对策等作一简要综述,并进一步指出有待研究的问题,为后续开展棉酚对家禽健康及畜产品安全的影响及其机理研究提供参考。     

棉酚对反刍动物的危害性及其瘤胃微生物学脱毒机理探讨

棉花在加工过程中所产生的棉籽、棉花壳、棉仁粉、棉粕等副产品是畜禽养殖业重要的饲料资源。与单胃动物相比,反刍家畜对棉副产品中棉酚毒性具有一定耐受性,但目前与棉酚相关的瘤胃微生物学脱毒机制尚不清楚。本文针对棉酚的危害性,重点综述了棉酚脱毒相关的化学与微生物学机理研究进展,以期为今后开展瘤胃微生物棉酚脱毒机制研究提供参考依据。     

育肥猪棉酚中毒的诊断和治疗

棉酚是存在于棉花色素腺中的一种不溶于水而溶于有机溶剂的黄褐色聚酚色素。结合棉酚在动物消化道内不被动物吸收，毒性很小；而游离棉酚则易被动物吸收，对动物毒性较大，尤其单胃动物过量摄取和摄取时间较长，可导致生长迟缓、繁殖性能及生产性能下降，甚至导致死亡。现将我团某猪场2002年发生此病的诊断治疗情况报告如下：     

饲料中游离棉酚测定方法的探讨

棉籽饼粕是重要的蛋白质饲料资源,是畜禽饲料中常用的饲料原料之一,但由于饼粕中含有棉酚,对动物具有毒性,因而使用上受到一定限制。棉籽饼粕中的棉酚按其存在形式可分为游离棉酚和结合棉酚。游离棉酚其分子结构中的活性基团(醛基与羟基)未被其他物质“封闭”,能损害动物的细胞     

饲料产品卫生指标检测方法注解

饲料产品卫生指标检测方法注解（４）胡冬生７．游离棉酚的测定游离棉酚对单胃动物有一定毒性，但对反刍类动物的毒性就小。因棉酚在瘤胃中与蛋白质的结合有关，游离棉酚在饲料中含量不高时（０．０１５％以下）对家禽是安全的，然而蛋鸡料中少量棉酚（０．００５％左右）...     

游离棉酚对奶牛繁殖性能的影响

<正>棉籽壳、棉籽饼粕等棉花副产品富含蛋白质,其中也含有有毒物质棉酚及其衍生物,如果未经脱毒处理或调制不当大量或长期饲喂,可引起棉酚慢性中毒。由于棉酚从动物体内排出周期较长,因此食用棉酚后的毒性是积累性的、渐进     

棉酚对蛋鸡的影响

棉酚是棉籽饼粕中的主要的有毒物质．蛋鸡日粮中游离棉酚含量过高会给动物健康、生产性能及蛋品质带来负面影响．日粮添加硫酸亚铁在一定程度上可缓解游离棉酚的毒性。本文综述了游离棉酚对蛋鸡生产性能及蛋品质影响以及日粮硫酸亚铁对游离棉酚的脱毒效果。     

棉籽蛋白如何脱毒

<正> 我国年产棉仁饼粕五十多亿斤,含粗蛋白二十多亿斤,是一项重要的植物蛋白资源。普通棉籽中含棉酚1.6～2.8％,游离状态的棉酚对单胃动物有毒性。因此,要使棉籽蛋白充分发挥利用价值,必须消除棉籽中的棉酚毒素。解决的途径:一是培育不含棉酚(或含量极少)的“无毒棉”;二是从棉籽加工工艺方面采取消除或降低棉酚毒素的措施,使其含量降低到适于食用或饲用的安全标准以下。对含有棉酚的普通棉饼,除可以直接限量     

Gossypol as a toxicant in livestock

Many cases of gossypol toxicity have been misdiagnosed. The long-held belief that gossypol toxicity did not occur in ruminants has been a major hurdle to overcome. Field necropsies in which pulmonary congestion and edema were attributed to shipping-fever pneumonia, failure to examine the heart either grossly or microscopically, failure to believe that 200 ppm free gossypol could kill a calf, failure to believe that any age of sheep could suffer gossypol toxicity, and failure to believe that just because you fed the same thing last year, it will not cause a problem this year, all were factors in causing the misdiagnosis of this toxicity. Gossypol toxicity cases diagnosed will increase each year because of increased awareness among veterinarians. Continued research will help to increase our understanding of this multifactored toxin and, possibly, devise ways to detoxify it before it is utilized in a feed. Until then, it will have to be considered because it will continue to be present as a potential toxicant in the feed.     

育肥牛棉酚中毒的诊断与治疗

棉酚中毒是由于长期、过量饲喂含游离棉酚超标的棉副产品,引起的以出血性胃肠炎、血红蛋白尿以及雄性生殖毒性和母畜流产为主要特征的中毒病。新疆是我国的棉花主产区,棉花加工过程中产生了大量的棉籽饼、棉籽粕、棉壳等副产品,这些副产品是优质的动物饲料来源,具有产量多、来源广、价格便宜、适口性好的特点,广泛应用于肉牛和肉羊的育肥。本文通过对育肥牛棉酚中毒的诊断与治疗,重点阐述棉酚中毒的发病机理、治疗手段与预防措施,以期为棉酚中毒的预防治疗及有效脱毒合理饲喂提供一定的参考。     

Heart failure caused by gossypol poisoning in two dogs

Two hound-type dogs from the same kennel were admitted in terminal stages of congestive heart failure. An investigation revealed the owner had been feeding the dogs cottonseed meal daily with their kibbled meal. Gossypol toxicosis from feeding this meal caused marked abnormalities in myocardial contractility. Although in severe congestive heart failure, one dog had only minimal dilatation of its heart, as revealed by thoracic radiography. Disseminated intravascular coagulopathy also was diagnosed in this dog. Gossypol is a cumulative toxin; the amount of free gossypol fed was approximately 5.4 to 5.7 mg/kg/day for an unknown duration.     

Gossypol detoxification in the rumen and Helicoverpa armigera larvae: A review

Gossypol, a phenolic compound found in the cotton plant, is widely distributed in cottonseed by-products. Although ruminant animals are believed to be more tolerant of gossypol toxicity than monogastric animals due to rumen microbial fermentation, the actual mechanisms of detoxification remain unclear. In contrast, the metabolic detoxification of gossypol by Helicoverpa armigera (Lepidoptera: Noctuidae) larvae has achieved great advances. The present review discusses the clinical signs of gossypol in ruminant animals, as well as summarizing advances in the study of gossypol detoxification in the rumen. It also examines the regulatory roles of several key enzymes in gossypol detoxification and transformation known in H. armigera. With the rapid development of modern molecular biotechnology and -omics technology strategies, evidence increasingly indicates that research into the biological degradation of gossypol in H. armigera larvae and some microbes, in terms of these key enzymes, could provide scientific insights that would underpin future work on microbial gossypol detoxification in the rumen, with the ultimate aim of further alleviating gossypol toxicity in ruminant animals.     

Gossypol inhibits LH‐induced steroidogenesis in bovine theca cells

Gossypol, a polyphenolic aldehyde found in cottonseed, has been shown to perturb steroidogenesis in granulosa and luteal cells of rats, pigs and cattle. However, little is known about the direct effect of gossypol on theca cell functions in any species. The present study was conducted to investigate the effect of gossypol on the steroidogenesis and the expression of genes involved in it in cultured bovine theca cells. Theca cells were isolated from healthy preovulatory follicles and were cultured in the presence of luteinizing hormone (LH) for up to 7 days. During the culture period, main steroid products of the theca cells shifted from androstenedione (A4) at day 1 to progesterone (P4) from day 2 onward. At days 1 and 7, theca cells were treated with gossypol (0‐25 μg/mL) for 24 h. Gossypol inhibited LH‐stimulated theca cell A4 and P4 production in a dose‐dependent manner at both occasions. The viability of theca cells was not affected by gossypol at any doses used. Gossypol down‐regulated expressions of steroidogenic enzymes CYP11A1, HSD3B1 and CYP17A1, but not that of LHR. These results indicate that gossypol inhibits thecal steroidogenesis through down‐regulating gene expressions of steroidogenic enzymes but without affecting cell viability in cattle.     

棉酚对奶牛繁殖性能的影响研究

棉酚是一种存在于棉族植物的棉籽、根、茎杆色素腺里的黄色有毒多酚物质,是棉族植物抵御害虫的保护剂,但是棉籽产品用作动物饲料时,长时间或超剂量使用棉酚就会导致中毒,尤其是损坏动物的繁殖性能,本文综述了棉酚对奶牛繁殖性能的影响以及部分试验报道的安全剂量,以亟为合理配制饲料提供理论依据。     

Pathology and histopathology of gossypol toxicity in broiler chicks

Two experiments were conducted to determine the toxicity, pathology, and histopathology of purified gossypol in broiler chicks. Gossypol was added to broiler feed at 0, 100, 200, and 400 mg/kg of feed in Experiment 1 and at 0, 800, and 1600 mg/kg of feed in Experiment 2. Day-old broiler chicks were fed these diets from 1 to 21 days in Experiment 1 and from 1 to 23 days in Experiment 2. In Experiment 1, body weight and feed intake at 21 days were not significantly affected by dietary gossypol. However, chicks fed gossypol at 400 mg/kg of feed had poor feed conversion ratio compared with the other treatment. Feed conversion ratios were 1.493, 1.564, 1.471, and 1.60 for chicks fed gossypol at 0, 100, 200, and 400 mg/kg of feed, respectively (Experiment 1). Chicks fed 400 mg/kg gossypol also had mild perivascular lymphoid aggregate formations and bilary hyperplasia in the liver. In Experiment 2, gossypol at 1600 mg/kg resulted in 28.1% mortality. Gossypol at 800 and 1600 mg/kg feed resulted in significant decreases in body weight and feed intake of chicks. The average body weights of 23-day-old chicks in Experiment 2 were 676, 224, and 111 g for 0, 800, and 1600 mg/kg gossypol, respectively. Feed conversion ratios of chicks fed 800 and 1600 mg/kg gossypol were significantly higher than those of chicks fed control diets (1.383 vs. 1.564 vs. 1.745 for 0, 800, and 1600 mg/kg gossypol, respectively). Plasma iron and hematocrit values were significantly reduced by gossypol at 800 and 1600 mg/kg of feed. Enlarged gallbladder was the only gross pathology symptom associated with gossypol levels. Severe cases of perivascular lymphoid aggregate formation, biliary hyperplasia, and hepatic cholestasis were observed in chicks fed 800 and 1600 mg/kg of gossypol in feed. No gossypol-related changes were observed in kidney tissues of chicks. These results show that gossypol is toxic to broiler chicks at high levels. This study also shows that histopathologic changes in liver due to gossypol also occur at levels lower than the levels that affect body weight.     

Gossypol toxicosis in a herd of beef calves

A 6-month-old crossbred calf was examined as representative of a herd of calves experiencing dyspnea and death, with few other clinical signs of illness. Physical examination of the calf identified pleural and peritoneal effusion and poor body condition. The calf did not respond to supportive treatment, and necropsy of it and another calf from the herd identified congestive heart failure as the cause of death. Gossypol toxicosis was the cause of congestive heart failure in this herd; the source of the toxin was a cottonseed meal and cottonseed hull ration fed by the owner.     

棉酚对猪原代培养黄体细胞增殖和凋亡的影响

采用长大杂母猪原代培养的黄体细胞,通过MTT法、DNA Ladder和TUNEL检测法,探讨了0、0.4、2、10、50 mg/L棉酚对猪原代培养黄体细胞增殖和凋亡的影响.结果表明,棉酚分别染毒24、48 h后,与对照组比较,各浓度组对黄体细胞增殖具有明显的抑制作用(P<0.05,P<0.01),黄体细胞的凋亡率达5%～23%;这种细胞毒性作用呈剂量相关性,在一定剂量下,具有时间依赖关系.     

Inhibition by gossypol of cyclic nucleotide-independent phosvitin kinase from pig testis

Gossypol, a male anti-fertility agent, was found to be an inhibitor of cyclic nucleotide-independent phosvitin kinase from pig testis. The IC50 value (concentration causing 50% inhibition) was 42 microM using phosvitin as substrate. Kinetic analysis indicated that the compound inhibited the enzyme noncompetitively with respect to ATP (Ki = 17 microM) and competitively with respect to phosvitin (Ki = 11 microM). The gossypol inhibition was reversed by the addition of polyamines. The compound also inhibited phosphorylation of high mobility group (HMG) proteins HMG 14 and 17 (the endogenous substrates in the testis located in nucleosome), with an IC50 value of 48 microM.