Department of Animal Science, Colorado State University, Fort Collins, CO 80523,
J Anim Sci. 2011 Feb;89(2):538-48. doi: 10.2527/jas.2009-2675. Epub 2010 Oct 8.
During marketing, cattle may be exposed to periods of water deprivation. The impact of water and feed access and health status on the physiological well-being and carcass characteristics of Holstein slaughter cows during preslaughter marketing was studied through analysis of serum components, BW loss percentage, and fresh meat composition. Ninety-one multiparous Holstein cows (609 ± 89 kg mean BW, 2.9 ± 0.5 mean BCS, varying stage of lactation) were purchased over 3 wk in 3 groups (n = 31, 29, and 31) at a terminal market in central Wisconsin. Each cow was screened to determine health status (sick or not sick) and randomly assigned to 1 of 3 water and feed withdrawal treatment pens (AL, ad libitum access to water for 36 h; 18H, 18 h of ad libitum access to water followed by 18 h of water withdrawal; 36H, 36 h of water withdrawal; all 3 treatments included 36 h of feed withdrawal) in a randomized complete block arrangement with repeated measures for serum components. Blood samples were collected by tail venipuncture at 0, 9, 18, 27, and 36 h of each treatment. Ambient temperatures were 1.9 ± 6.2°C during the trial period, which occurred over a 3-wk period in March and April 2007 near Arlington, WI. No difference (P > 0.05) was observed in mean serum cortisol in AL (18.41 ± 2.17 ng/mL) or 36H (22.98 ± 2.17 ng/mL). Mean serum glucose was greater (P < 0.05) in 36H pens (78.15 ± 0.77 mg/dL) than AL (75.91 ± 0.77 mg/dL). Mean serum creatinine was greater (P < 0.05) in 36H pens (0.71 ± 0.03 mg/dL) than AL (0.60 ± 0.03 mg/dL). The 36H pens also displayed increased (P < 0.05) serum albumin, anion gap, Ca, Cl, Na, cholesterol, and aspartate aminotransferase over AL. Greater (P < 0.05) mean percentage BW loss was observed in 36H pens (5.2 ± 0.6%) than AL (3.1 ± 0.6%). Mean muscle protein (%) was greater (P < 0.05) in 36H (22.2 ± 0.4%) than 18H (21.3 ± 0.4%). Mean muscle moisture (%) was greater (P < 0.05) in AL and 18H (75.3 ± 0.4% and 75.2 ± 0.4%) than 36H. Mean 24-h pH values were 5.92 (AL), 5.92 (18H), and 5.81 (36H; SE = 0.04) and were not different (P < 0.05). Observed pH and color values indicated a borderline dark-cutter state across all cattle in the study, regardless of water and feed access treatment. Based on these results, water and feed withdrawal in lairage should not exceed 18 h during the marketing of Holstein slaughter cows acclimated to springtime conditions to maintain BW, serum component concentrations, and fresh meat composition.
在营销过程中,牛可能会经历一段时间的缺水。本研究通过分析血清成分、BW 损失百分比和鲜肉成分,研究了水和饲料供应以及健康状况对荷斯坦屠宰牛在预屠宰营销期间生理健康和胴体特征的影响。在威斯康星州中部的一个终端市场,3 组(每组 31、29 和 31 头)共购买了 91 头经产荷斯坦奶牛(平均体重 609±89kg,平均体况评分 2.9±0.5,泌乳期不同阶段)。每头牛都经过筛选以确定健康状况(患病或未患病),并随机分配到 3 个水和饲料撤出处理栏(AL,36 小时内自由饮水;18H,18 小时自由饮水,然后 18 小时断水;36H,36 小时断水;所有 3 种处理均包括 36 小时禁食),采用随机完全区组设计,血清成分进行重复测量。在每个处理的 0、9、18、27 和 36 小时通过尾静脉采血。试验期间环境温度为 1.9±6.2°C,试验于 2007 年 3 月和 4 月在威斯康星州阿灵顿附近进行,持续 3 周。AL(18.41±2.17ng/mL)或 36H(22.98±2.17ng/mL)中皮质醇的平均值没有差异(P>0.05)。36H 栏中的血清葡萄糖平均值(78.15±0.77mg/dL)高于 AL(75.91±0.77mg/dL)(P<0.05)。36H 栏中的血清肌酐平均值(0.71±0.03mg/dL)高于 AL(0.60±0.03mg/dL)(P<0.05)。36H 栏还显示血清白蛋白、阴离子间隙、Ca、Cl、Na、胆固醇和天门冬氨酸转氨酶增加(P<0.05)。36H 栏的平均 BW 损失百分比(5.2±0.6%)高于 AL(3.1±0.6%)(P<0.05)。36H 栏的肌肉蛋白质(%)平均值(22.2±0.4%)高于 18H(21.3±0.4%)(P<0.05)。AL 和 18H 栏的肌肉水分平均值(75.3±0.4%和 75.2±0.4%)高于 36H(P<0.05)。24 小时平均 pH 值为 5.92(AL)、5.92(18H)和 5.81(36H;SE=0.04),且无差异(P<0.05)。研究中所有牛的观察 pH 值和颜色值表明处于边缘暗切割状态,无论水和饲料供应处理如何。基于这些结果,在适应春季条件的荷斯坦屠宰牛的营销过程中,水和饲料的撤出不应超过 18 小时,以维持 BW、血清成分浓度和鲜肉成分。