Rogers G M, Poore M H, Ferko B L, Brown T T, Deaton T G, Bawden J W
Department of Food Animal, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
J Am Vet Med Assoc. 1999 Mar 1;214(5):681-7.
To determine whether feeding sweetpotato cannery waste (SPCW) to cattle had adverse effects on dental wear, growth performance, or ruminal tissues.
Clinical trial.
36 Holstein steers.
Steers were assigned to 1 of 3 groups. All steers received ryegrass hay ad libitum. In addition, steers in group 1 were fed 3.2 kg of corn and soybean meal/steer/d, steers in group 2 were fed 0.45 kg of soybean meal/steer/d and SPCW ad libitum, and steers in group 3 were fed a mixture of SPCW and broiler litter ad libitum. Samples of rumen fluid were collected on day 56. Steers were slaughtered on day 84, and samples of rumen were submitted for histologic examination. Teeth from control steers were removed, and calcium ion loss in response to etching with 2.28% lactic acid solutions buffered to pH of 3.75, 4.0, 4.25, 4.5, and 4.75 was determined.
Average daily gain was lower for steers fed SPCW than for steers in the other 2 groups. Steers fed the SPCW-broiler litter mixture had only mild increases in tooth wear and tooth color scores, compared with control steers, whereas steers fed unbuffered SPCW had substantial increases in tooth wear and tooth color scores. Histologic abnormalities were detected in rumens from steers fed diets containing SPCW. Calcium ion loss decreased as pH of the etching solution increased.
Results indicate that feeding cattle unbuffered SPCW can cause dental erosion, ruminal epithelial changes, and poor growth; however, SPCW buffered with broiler litter can be used as a cattle feed.
确定用甘薯罐头厂废料（SPCW）喂牛是否会对牙齿磨损、生长性能或瘤胃组织产生不良影响。
临床试验。
36头荷斯坦公牛。
将公牛分为3组。所有公牛均自由采食黑麦草干草。此外，第1组公牛每头每天喂3.2千克玉米和豆粕，第2组公牛每头每天喂0.45千克豆粕并自由采食SPCW，第3组公牛自由采食SPCW与肉鸡垫料的混合物。在第56天采集瘤胃液样本。在第84天宰杀公牛，并将瘤胃样本送去做组织学检查。取出对照公牛的牙齿，测定用pH值为3.75、4.0、4.25、4.5和4.75的2.28%乳酸溶液蚀刻后钙离子的流失情况。
采食SPCW的公牛平均日增重低于其他两组公牛。与对照公牛相比，采食SPCW与肉鸡垫料混合物的公牛牙齿磨损和牙齿颜色评分仅略有增加，而采食未缓冲SPCW的公牛牙齿磨损和牙齿颜色评分大幅增加。在采食含SPCW日粮的公牛瘤胃中检测到组织学异常。随着蚀刻溶液pH值的升高，钙离子流失减少。
结果表明，用未缓冲的SPCW喂牛会导致牙齿侵蚀、瘤胃上皮变化和生长不良；然而，用肉鸡垫料缓冲的SPCW可用作牛饲料。
