Applegate T J, Schatzmayr G, Prickel K, Troche C, Jiang Z
Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Poult Sci. 2009 Jun;88(6):1235-41. doi: 10.3382/ps.2008-00494.
The negative effects of aflatoxins (AFLA) on hepatic necrosis and total tract digestibility of energy, N, and amino acids have been well documented. However, the question remains if this is an effect on nutrient metabolizability alone or an effect on the intestine, or both, resulting in increased endogenous nutrient loss or reduced nutrient retention, or both. Therefore, a 2-wk feeding study with a crude AFLA culture was conducted with laying hens to measure endogenous losses and digestive functionality of the intestine. Hy-Line W36 hens were fed 1 of 4 experimental diets containing a crude AFLA culture from 20 to 22 wk of age. Diets were analyzed to contain 0, 0.6, 1.2, or 2.5 mg/kg of AFLA B(1). Dietary AFLA concentration had no effect on BW, egg production, or feed intake. Intestinal crypt depth (but not villus length) increased linearly with increasing AFLA concentration. Similarly, specific activity of the intestinal disaccharidase, maltase, increased quadratically by feeding up to 1.2 mg/kg of AFLA and declined at 2.5 mg/kg of AFLA (P <or= 0.022). Although there was no effect of AFLA on goblet cell number, density, or crude mucin excretion (P > 0.05), sialic acid excretion increased quadradically such that it was increased 12% when 0.6 and 1.2 mg/kg of AFLA was fed versus the control (P <or= 0.025). Digestibility of DM and N per hen per day were unaffected by AFLA. Feeding of 0.6 and 1.2 mg/kg reduced the apparent digestible and AME(n) of the hen by 10 and 4%, respectively (P <or= 0.025). Because intestinal characteristics (intestinal morphology, sialic acid production, and apparent digestible energy) were altered by AFLA feeding, it can be surmised that AFLA can have a direct or indirect effect, or both, on functionality of the gastrointestinal tract.
黄曲霉毒素（AFLA）对肝脏坏死以及能量、氮和氨基酸的全肠道消化率的负面影响已有充分记录。然而，问题依然存在：这仅仅是对营养物质代谢率的影响，还是对肠道的影响，抑或是两者皆有，从而导致内源性营养物质损失增加或营养物质保留减少，或两者兼而有之。因此，用粗制AFLA培养物对蛋鸡进行了为期2周的饲养研究，以测定内源性损失和肠道消化功能。海兰W36蛋鸡在20至22周龄时饲喂4种含粗制AFLA培养物的实验日粮中的一种。分析日粮中AFLA B(1)的含量为0、0.6、1.2或2.5毫克/千克。日粮AFLA浓度对体重、产蛋量或采食量没有影响。肠道隐窝深度（而非绒毛长度）随AFLA浓度增加呈线性增加。同样，肠道双糖酶麦芽糖酶的比活性在饲喂高达1.2毫克/千克AFLA时呈二次方增加，而在2.5毫克/千克AFLA时下降（P≤0.022）。尽管AFLA对杯状细胞数量、密度或粗粘蛋白排泄没有影响（P＞0.05），但唾液酸排泄呈二次方增加，以至于饲喂0.6和1.2毫克/千克AFLA时比对照组增加了12%（P≤0.025）。每只母鸡每天的干物质和氮消化率不受AFLA影响。饲喂0.6和1.2毫克/千克分别使母鸡的表观可消化能和氮校正代谢能降低了10%和4%（P≤0.025）。由于饲喂AFLA会改变肠道特征（肠道形态、唾液酸产生和表观可消化能），可以推测AFLA可能对胃肠道功能有直接或间接影响，或两者皆有。
