摘要
Plant secondary metabolites (PSM) such as condensed tannins, hydrolysable tannins, saponins and essential oils purportedly impact rumen fermentation at low inclusion rates in beef cattle diets. Twelve steers (347 ± 23 kg BW) of British and continental influence were allocated to 1 of 4 replicated 3 x 3 Latin squares. Latin squares each had 14 d periods (10 d adaptation and 4 d for sample collection). All cattle were fed ground warm-season hay (89.5% DM, 92.8% OM, 65.9% NDF, 43.6% ADF, 6.70% CP) at 1.5% of BW (DM-basis) and supplemented with soybean meal at 0.18% of BW (DM-basis) once daily. Treatments consisted of a blend of tannins, saponins and essential oils provided at 0% (Control), 0.1% (Low) and 0.3% (High) of hay offering. Treatments were mixed with daily soybean meal allotment and provided before feeding of hay. Urine and feces were completely collected from d 11 through 14 at 0730 h and daily amounts of urine and feces produced were measured gravimetrically. Measures of gaseous exchange were determined via indirect calorimetry on d 13 and 14. Open-circuit respiration calorimeters (91.4 × 91.4 × 191.2 cm) were used to collect respired gas and ruminal methane production. Total oxygen consumption and production of carbon dioxide and methane were calculated from the difference in concentration of oxygen, carbon dioxide, and methane from air exhausted from each calorimeter and concentration of oxygen, carbon dioxide, and methane in ambient air and multiplied by amounts of air flowing from each calorimeter standardized for temperature, pressure, and humidity. Data were analyzed for a Latin square using the MIXED procedure of SAS with fixed effect of treatment, period and square and random effect of steer. Linear and quadratic contrast coefficients were assigned using PROC IML for uneven spacing of treatments. Significance was declared when P ≤ 0.05. Per experimental design, forage N and OM intake did not differ (P ≥ 0.77). Apparent total tract digestion of OM, NDF and ADF did not differ (P ≥ 0.66) among treatments. Fecal nitrogen excretion, and the percentage of N excreted in feces increased linearly (P = 0.01). N balance tended (P = 0.08) to decrease linearly with increasing PSM supplemented. Methane (L/kg DMI) was not affected (P = 0.28) by treatments. Methane, GE, DE, and ME (mcal/kg DMI) was unaffected (P = 0.19) by treatment. Under the conditions of this experiment, a blend of PSM had little effect on rumen fermentation or energy metabolism in beef steers.
摘要译文
植物二次代谢产物（PSM），例如凝结的单宁，可水解的单宁，皂苷和精油，据称在牛奶饮食中以低包含率影响瘤胃发酵。将英国影响的十二个牛头（347±23 kg bw）分配给了4个复制的3 x 3拉丁正方形中的1个。拉丁正方形每个有14 d期（10 d适应，4 d用于样品收集）。所有牛都在BW（DM-BASIS）的1.5％（DM-BASIS）的1.5％，供应地面暖季干草（89.5％DM，92.8％OM，65.9％NDF，43.6％的ADF，6.70％CP），并补充了BW的0.18％的BW（DM-BASIS）每天一次。处理由单宁，皂苷和精油的混合物组成，分别为0％（对照），0.1％（低）和0.3％（高）干草产品。将治疗与每日大豆餐分配混合，并在干草喂食之前提供。在0730 h时从d 11到14完全收集尿液和粪便，每天测量每天产生的尿液和粪便。通过在D 13和14上的间接量热法确定气态交换的度量。使用开路呼吸量热法（91.4×91.4×191.2 cm）用于收集呼吸气和瘤胃甲烷的产生。根据氧气，二氧化碳和甲烷的浓度差异，从每种热量计和氧气浓度耗尽的空气中，计算二氧化碳和甲烷的总氧气和产生从每个热量表中流动，以温度，压力和湿度为准。使用SAS的混合程序分析了数据的数据，并具有固定的治疗，周期和正方形以及转向的随机效应。使用PROC IML分配了线性和二次对比系数，以进行处理不平衡。p≤0.05时宣布了显着性。根据实验设计，草料N和OM摄入量没有差异（P≥0.77）。在处理中，OM，NDF和ADF的明显总道消化没有差异（p≥0.66）。粪便氮的排泄，粪便中排泄的N百分比线性增加（p = 0.01）。n平衡倾向于（p = 0.08），随着补充PSM的增加而降低线性。甲烷（L/kg DMI）不受治疗影响（p = 0.28）。甲烷，GE，DE和ME（MCAL/KG DMI）未通过治疗受到影响（p = 0.19）。在该实验的条件下，PSM的混合物对牛肉ste牛的瘤胃发酵或能量代谢几乎没有影响。
Emily A Petzel [1]; Eric Bailey [1]; Derek W Brake [1]. 145 The effect of a plant secondary metabolite blend on energy metabolism and nutrient balance of beef cattle consuming low-quality warm season grass hay[J]. Journal of Animal Science, 2024,102(Sup1): 71-72