摘要
Two experiments were conducted to evaluate the inclusion of cotton byproducts in feedlot finishing diets on the performance and carcass traits of steers and to evaluate the in situ ruminal degradability of the individual diet components and treatment diets. In experiment 1, crossbred beef steers (n = 64; BW = 318 ± 12.3 kg) were assigned to 1 of 2 experimental treatments in a randomized complete block design (8 pens/treatment; 4 steers/pen). Treatments included a control diet (CON; prairie hay (PH), Sweet Bran, dry-rolled corn, and a liquid fat supplement), and a cotton byproduct diet (CTN; cotton gin trash (CGT), whole cottonseed, dry-rolled corn, and water). Both contained urea and a vitamin and mineral supplement. Over the entire feeding period, DMI (P = 0.04), and ADG (P = 0.08) was greater for CTN steers than CON steers with no difference in G:F (P = 0.86). The CTN steers tended to have heavier final BW (P = 0.09) and had a heavier hot carcass weight (P = 0.02), and greater fat thickness (P = 0.03) than CON steers. The CON steers tended to have a lower USDA Yield Grade (P = 0.07), less KPH (P = 0.09), and decreased dressing percentage (P = 0.10) than CTN steers. In experiment 2, six ruminally cannulated steers were used in a crossover design. In-situ bags containing individual ingredients and whole diet samples were incubated in the rumen for up to 96 h in steers consuming the same diets as experiment 1. The A, B, and C fractions, Kd and effective degradability of DM and OM were not different between CON and CTN substrates (P ≥ 0.25). No differences (P ≥ 0.37) were detected for the % NDF disappearance at 48 h between CON and CTN substrates. When the CON substrate was incubated in steers consuming the CON diet, effective degradability of starch was not different (P = 0.84) from when the CTN diet was incubated in steers consuming the CTN diet. These experiments suggests that cotton byproducts can be utilized in finishing diets of beef cattle with no adverse effects on performance or digestibility.
摘要译文
进行了两个实验，以评估育肥场育成日粮中的棉花副产品对ste牛皮的性能和car体特性的影响，并评估单个日粮成分和处理日粮的瘤胃可降解性。在实验1中，杂交牛ste牛（n = 64； BW = 318±12.3千克）分配给随机完全块设计的2种实验处理之一（8笔/处理； 4圈/笔）。治疗包括对照饮食（CON；草原干草（PH），甜麸皮，干轧玉米和液态脂肪补充剂，以及棉花副产品饮食（CTN；轧棉废料（CGT），全棉种子，干轧玉米和水）。两者都包含尿素以及维生素和矿物质补充剂。在整个饲喂期间，CTN ers牛的DMI（P = 0.04）和ADG（P = 0.08）大于CON ers牛，G：F无差异（P = 0.86）。 CTN ers牛皮的最终体重较CON ers牛皮的偏重（P = 0.09），热car体重量（P = 0.02）和脂肪厚度（P = 0.03）更重。与CTN ers牛皮相比，CON ers牛皮的USDA产量等级较低（P = 0.07），KPH较低（P = 0.09），而选矿百分比降低（P = 0.10）。在实验2中，在交叉设计中使用了六个瘤胃插管的ste牛皮。在装有与实验1相同饮食的公牛中，将盛有单个成分和全部饮食样品的原位袋在瘤胃中保温长达96小时。DM，OM的A，B和C成分，Kd以及有效降解能力不佳CON和CTN基板之间的差异（P≥0.25）。 CON和CTN底物在48 h的NDF消失百分比没有差异（P≥0.37）。当CON底物在食用CON日粮的公牛中孵育时，淀粉的有效降解率与CTN日粮在食用CTN日粮的公牛中孵育时没有差异（P = 0.84）。这些实验表明，棉花副产品可用于肥育牛的日粮，对生产性能或消化率没有不利影响。
Warner, Andrea. Utilization of Cotton Byproducts in Cattle Finishing Diets: Impacts on Performance, Carcass Traits, and Ruminal Degradability of Diet Components[D]. US: Oklahoma State University, 2020