饲料中的霉菌毒素

霉菌毒素是真菌在田间、贮运中适宜条件下生长、产生的有毒物质。产生霉菌毒素的三种主要真菌有:曲霉菌、镰刀菌和青霉菌。 对霉菌毒素和中毒症的深入研究始于60年代。当时从一批有毒花生饼中分离出黄曲霉     

亚太地区霉菌毒素:普遍性、负面影响、经济后果及控制策略

抗营养因子影响饲料中营养成分的质量 ,最终降低畜禽的健康状况和生产性能。霉菌毒素就是一种存在于饲料原料和配合饲料中的抗营养因子 ,它们是由不同类属的真菌所产生的二级有毒的代谢产物。在家禽业中 ,产生霉菌毒素的真菌包括 :曲霉菌、镰刀菌、青霉菌。尽管如此多的霉菌毒素参与或导致了动物的代谢失调 ,而在亚太地区最为严重的包括 :黄曲霉毒素、赭曲霉素、橘霉素、T - 2毒素、呕吐毒素 (DON)、串珠镰孢菌毒素和玉米赤霉烯酮 (见表 1 )。由于缺乏系统分析的手段 ,更多的霉菌毒素在动物饲料中通常也无法检测出来 ,黄曲霉的存在也就意…     

警惕——霉菌毒素

霉菌毒素中毒症是由有毒真菌代谢产物(真菌毒素)所致的一种疾病。在所有霉菌中，92％的霉菌是无毒的；4％会造成家禽的霉菌性疾病，如禽的曲霉菌病等；4％的霉菌会产生霉菌毒素，如串珠镰刀菌毒素会产生串珠镰刀菌毒素、赭曲霉能产生赭曲霉毒素等。据有关资料报道，全世界供应的谷物中有25％受到霉菌毒素污染。中国禽场所使用的饲料中大部分存在不同程度的霉菌污染情况，此应引起广大同行的注意。     

饲料中的霉菌毒素

饲料中的霉菌毒素美国里查德·Ａ·默罗鲁克霉菌毒素是霉菌在田间或贮运过程中适宜条件下生长，产生的有毒物质。曲霉菌、镰刀菌和青霉菌是三种主要产毒素霉菌。一但湿度、温度和其它条件，如ＰＨ和植物逆境反应等适宜时，霉菌就会在谷物或饲料上生长，产生有毒代谢物。虽...     

青贮饲料中霉菌毒素的产生、毒性作用及脱毒研究进展

青贮饲料是反刍动物日粮中重要的组成部分,但青贮饲料在收获前、发酵期间及青贮完成后都会受到多种霉菌毒素污染。反刍动物摄入霉菌毒素后会对其健康和生产性能产生不利影响,并对食品安全及人类健康构成威胁。青贮饲料中优势霉菌包括镰刀菌属(Fusarium)、曲霉属(Aspergillus)、青霉属(Penicillium)和链格孢属(Alternaria)真菌,所产生的主要霉菌毒素包括单端孢霉烯族毒素、伏马菌素、玉米赤霉烯酮、黄曲霉毒素、赭曲霉毒素、蓝酪霉菌毒素、霉酚酸和麦角生物碱等。本文将对上述毒素在青贮饲料中的产生、影响、预防和脱毒的方法进行简要综述,以期为生产优质青贮饲料提供理论支持。     

饲料中霉菌毒素脱毒方法的研究进展

1主要产毒霉菌现在已明确能产生对人体毒害作用的霉菌有300多种,主要是曲霉菌属(aspergillus)、青霉菌属(pe nicilli-um)和镰刀菌属(fusarium)的霉菌产生。1.1曲霉菌属包括黄曲霉、杂色曲霉、构巢曲霉、棕曲毒、寄生曲霉、棒曲霉等。表面一般是绒毛状,开始为灰白色或白色,长出孢子后因菌种不同而呈现不同颜色。它们在生长繁殖过程中会产生黄曲霉毒素、赫曲霉毒素、杂色曲霉毒素等多种毒菌毒素。1.2镰刀菌属包括禾谷镰刀菌、三线镰刀菌、孢镰刀菌、梨孢镰刀菌、串珠镰刀菌、木贼镰刀菌、前病镰刀菌、粉红镰刀菌、尖孢镰刀菌等。一般呈白色绒…     

家禽饲料中霉菌及霉菌毒素的控制

Nyco意为真菌．mycotoxin为真菌毒素，而生产中常用于指常见的几种霉菌毒素，所以又称为霉菌毒素。现已知霉菌毒素超过300种，而对其中的大部分毒素相对毒性还不知道。产生毒素的真菌可在不同环节污染谷物类如玉米、高粱且产生毒素，如田间、收获期间、仓储期间。谷物在收获、仓储、饲料加工、农场不同环节霉菌毒素浓度通常逐步增加(表1)。对霉菌毒素水平的早期控制对降低到达禽舍前的饲料霉菌霉素浓度极为重要。根据联合国粮农组织资料，全世界每年有约25％的谷物遭受霉菌不同程度的污染。     

霉菌毒素对猪的危害及诊治

1基本情况 霉菌毒素是由谷物在田间、加工处理和仓储过程中生长的真菌产生的次级代谢产物。真菌在大田作物上产生霉菌毒素,称为＂大田毒素＂、＂镰刀菌毒素＂;在贮存过程中产生的毒素称为＂贮存毒素＂、     

饲料和饲草中霉菌毒素对动物生产性能的威胁

霉菌毒素是由真菌所产生的代谢产物，当采食生物显著量时，它对动物是有毒的，因此而得的疾病叫霉菌毒素中毒症。饲料谷物中霉菌的生长和霉菌毒素的产生受到许多因素的影响，但水分是最重要的因素。谷物贮存时，水分应保持在１５％以最大限度地抑制霉菌的生长。最普通的、最被人们所认识的、自由繁殖的霉菌毒素是黄曲霉毒素和镰刀菌霉菌毒素。饲草也可能含有复合的真菌生物碱。我们对黄曲霉毒素中毒症病因学的理解远远比对镰刀菌霉菌毒素中毒症的病因学了解得多。对因采食霉菌毒素污染的饲草而导致的中毒症的病因学更了解甚少。这可能是因为…     

常见霉菌毒素对猪的危害及防控策略

霉菌毒素是真菌产生的次级代谢产物,常见的霉菌包括,曲霉菌、镰刀菌和青霉菌,它们可在农作物生长和收获期间及加工后的作物上生长。猪饲料中最常见的霉菌毒素有黄曲霉毒素、呕吐毒素、玉米赤霉烯酮、烟曲霉毒素和赭曲霉毒素等,偶尔还伴有其他霉菌毒素的污染。霉菌毒素不但对猪产     

电感耦合等离子-质谱法测定饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅

应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。     

Supplementation of broodmares with copper, zinc, iron, manganese, cobalt, iodine, and selenium

In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum.     

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.     

液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估

采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度.     

Granulocyte isolation from whole blood of goat, sheep, cattle, horse, dog, pig, and man

A simple two step procedure for the isolation of caprine, ovine, bovine, equine, canine, porcine and human peripheral blood granulocytes is described. After enrichment of granulocytes by centrifugation, contaminating erythrocytes are lysed hypotonically. Recovery, purity, and viability of the granulocyte suspensions are determined. FACScan analysis of the cell suspensions measuring cellular size by forward and sideward light scatter is compared with the corresponding analysis of whole blood leukocytes. Constituencies of the isolated cell suspensions and loss of granulocyte subpopulations through isolation procedure is discussed with regard to granulocyte function assays.