Texas A&M AgriLife Research, Amarillo, TX.
Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS.
J Anim Sci. 2020 Dec 1;98(12). doi: 10.1093/jas/skaa390.
To address the gaps in current scientific knowledge, the objective of the present study was to investigate the impact of fumonisin exposure on feedlot cattle intake and performance. Fifty steers were received (day 0; 361 ± 6.4 kg), housed individually and fed once daily at 0800 hours. All steers were transitioned to a dry-rolled corn-based finishing diet from days 0 to 21 and then were fed the control finishing diet until day 50. Treatment diets were formulated to achieve ≤5 (CON), 15 (15PPM), 30 (30PPM), 60 (60PPM), or 90 ppm (90PPM) of total dietary fumonisin. Steers were fed the fumonisin treatment diets from day 50 until harvest on day 160; individual animal body weights (BW) were measured on days 0, 50, 100, 150, 159, and 160. Liver, kidney, and skeletal muscle tissue samples were collected at harvest for histopathological analyses, and liver samples were further analyzed for sphinganine (SA) and sphingosine (SO) concentration. Animal performance, carcass data, and liver enzyme concentration were analyzed using a mixed model; categorical data were analyzed via nonparametric models. Contrasts were used to test for linear and quadratic responses. Throughout the study, there was no effect of treatment (P > 0.60), or a linear response (P > 0.16) from increasing fumonisin levels, on BW or dry matter intake (DMI). However, CON tended to have a lower average daily gain (ADG) than the fumonisin treatments during the fumonisin treatment period (P = 0.10), and there was a positive linear response (P = 0.02) of ADG to fumonisin during the treatment period. There were no treatment differences in hot carcass weight, dressing percentage, marbling score, ribeye area, or yield grade. There were no effects of treatment on either liver abscesses (P = 0.95) or telangiectasis (P = 0.13). We observed a treatment difference for SA and SA:SO (P < 0.01), as well as a quadratic response (P < 0.02); both SA and SA:SO increased as dietary fumonisin increased. There were no observed differences between treatments for histopathology scores of kidney (P = 0.16), liver (P = 0.25), or skeletal muscle (P = 0.59) tissue. No adverse effects were observed in steers fed increasing dietary levels of fumonisin for 110 d prior to harvest. While elevated liver amino alcohol concentration did occur, negative effects on growth and carcass characters were not observed.
为了弥补当前科学知识的空白，本研究的目的是调查伏马菌素暴露对育肥牛采食量和性能的影响。将 50 头公牛（第 0 天；361 ± 6.4kg）接收，单独饲养，每天 0800 时一次性喂食。所有的牛都从第 0 天到第 21 天过渡到干压玉米基础育肥日粮，然后用对照育肥日粮喂养，直到第 50 天。处理日粮的配方旨在实现≤5（CON）、15（15PPM）、30（30PPM）、60（60PPM）或 90ppm（90PPM）的总膳食伏马菌素。牛从第 50 天开始喂食伏马菌素处理日粮，直到第 160 天收获；在第 0、50、100、150、159 和 160 天测量牛的个体体重（BW）。在收获时采集肝脏、肾脏和骨骼肌组织样本进行组织病理学分析，并进一步分析肝脏样本中的鞘氨醇（SA）和神经鞘氨醇（SO）浓度。使用混合模型分析动物性能、胴体数据和肝脏酶浓度；通过非参数模型分析分类数据。使用对比来测试线性和二次响应。在整个研究过程中，处理（P > 0.60）或随着伏马菌素水平的增加而呈线性响应（P > 0.16）对 BW 或干物质采食量（DMI）没有影响。然而，与伏马菌素处理相比，CON 在伏马菌素处理期间的平均日增重（ADG）较低（P = 0.10），并且 ADG 对处理期间的伏马菌素呈正线性响应（P = 0.02）。胴体重量、屠宰率、大理石花纹评分、肋眼面积或产肉等级无处理差异。处理对肝脓肿（P = 0.95）或血管扩张（P = 0.13）均无影响。我们观察到鞘氨醇和鞘氨醇：SO（P < 0.01）以及二次响应（P < 0.02）存在处理差异；随着日粮伏马菌素的增加，SA 和 SA：SO 均增加。在肾脏（P = 0.16）、肝脏（P = 0.25）或骨骼肌（P = 0.59）组织的组织病理学评分方面，处理之间无差异。在收获前 110 天，牛喂食逐渐增加的膳食伏马菌素水平，没有观察到不良反应。虽然肝脏氨基酸醇浓度升高，但未观察到生长和胴体特性的负面影响。
