Mitigation strategies are vital in minimizing the health and economic risks associated with dairy cattle exposure to aflatoxin (AF). The objective of this study was to determine the effects of a commercially available aluminosilicate clay in a lactation diet on production responses, blood chemistry, and liver inflammatory markers of multiparous lactating Holstein cows during an AF challenge. Sixteen multiparous lactating Holstein cows [body weight (mean ± SD) = 758 ± 76 kg; days in milk = 157 ± 43 d] were assigned to 1 of 4 treatments in a replicated 4 × 4 Latin square design with 21-d periods: no adsorbent and no AF challenge (CON), no adsorbent and an AF challenge (POS), 113 g of aluminosilicate clay top-dressed on the total mixed ration (adsorbent; FloMatrix, PMI Nutritional Additives, Arden Hills, MN) with an AF challenge (F4), or 227 g of adsorbent with an AF challenge (F8). The challenge consisted of 100 μg of AFB₁/kg of dietary dry matter intake administered orally. For each period, milk was sampled 3× daily from d 14 to 21; blood, feces, and urine were sampled on d 14, 18, and 21; and liver samples were taken on d 18. Liver tissue was assessed for gene expression and histological hepatocyte inflammation. Statistical analysis was preformed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). Fat-corrected milk (POS = 37.2, F4 = 39.2, and F8 = 38.9 kg/d) increased as concentration of adsorbent in the diet increased. There was a decrease in milk AFM₁ concentration at d 18 as concentration of adsorbent in the diet increased (POS = 0.33, F4 = 0.32, and F8 = 0.27 µg/kg). There was a decrease in AFM₁ concentration in urine (POS = 2.10, F4 = 1.89, and F8 = 1.78 µg/kg) and AFB₁ concentration in feces (POS = 4.68, F4 = 3.44, and F8 = 3.17 µg/kg) as concentration of adsorbent in the diet increased. Cows in CON had greater concentrations of serum cholesterol (202 mg/dL) and plasma superoxide dismutase (2.8 U/mL) compared with cows in POS (196 mg/dL and 2.6 U/mL, respectively). Plasma glutamate dehydrogenase increased as concentration of adsorbent in the diet increased (POS = 37.8, F4 = 39.3, and F8 = 39.1 U/L). The expression of NFKB1 was greater in the liver of cows in POS (0.78) compared with cows in CON (0.70). The expression of MTOR was greater in the liver of cows in CON (1.19) compared with cows in POS (0.96). When compared with cows in CON, cows in POS had greater odds ratio for hepatocyte inflammation (odds ratio = 5.14). In conclusion, the adsorbent used in this study had a positive effect on milk production and hepatocyte inflammation and reduced AF transfer.

缓解策略对于最大程度地降低与奶牛接触黄曲霉毒素（AF）有关的健康和经济风险至关重要。这项研究的目的是确定在哺乳期日粮中市售的硅铝酸盐粘土对房颤激发期间多头泌乳荷斯坦奶牛的生产反应，血液化学和肝炎性标志物的影响。16头产奶的荷斯坦奶牛[体重（平均值±标准差）= 758±76 kg；牛奶中的天数= 157±43 d]被分配到重复处理的4×4拉丁方设计中，其中21天为4天的4种处理中的1种：无吸附剂，无AF激发（CON），无吸附剂和AF激发（POS） ，将113 g铝硅酸盐粘土按总混合日粮（吸附剂； FloMatrix，PMI营养添加剂，明尼苏达州Arden Hills）追肥，并进行AF挑战（F4），或227 g带有AF激发剂（F8）的吸附剂。挑战包括100μgAFB口服给予₁ / kg饮食干物质摄入量。对于每个时期，从第14天到21天每天3次采样牛奶；在第14、18和21天采集血液，粪便和尿液；并在第18天采集肝脏样品。评估肝组织的基因表达和组织学肝细胞炎症。统计分析是使用SAS（SAS Institute Inc.，Cary，NC）的MIXED和GLIMMIX程序进行的。随着饮食中吸附剂浓度的增加，经过脂肪校正的牛奶（POS = 37.2，F4 = 39.2和F8 = 38.9 kg / d）增加。随着日粮中吸附剂浓度的增加（POS = 0.33，F4 = 0.32和F8 = 0.27 µg / kg），牛奶AFM _1的浓度会降低。AFM ₁减少饮食中吸附剂的浓度（尿= POS = 2.10，F4 = 1.89和F8 = 1.78 µg / kg）和粪便中的AFB ₁浓度（POS = 4.68，F4 = 3.44和F8 = 3.17 µg / kg）增加。与POS奶牛（分别为196 mg / dL和2.6 U / mL）相比，CON奶牛的血清胆固醇（202 mg / dL）和血浆超氧化物歧化酶（2.8 U / mL）浓度更高。随着饮食中吸附剂浓度的增加，血浆谷氨酸脱氢酶增加（POS = 37.8，F4 = 39.3，F8 = 39.1 U / L）。POS（0.78）的母牛肝脏中NFKB1的表达高于CON（0.70）的母牛肝脏中的表达。MTOR的表达CON（1.19）奶牛肝脏中的脂肪含量高于POS（0.96）奶牛肝脏中的含量。与CON奶牛相比，POS奶牛肝细胞炎症的优势比更高（优势比= 5.14）。总之，本研究中使用的吸附剂对产奶和肝细胞炎症具有积极作用，并减少了AF转移。