Fisher M W, Muir P D, Gregory N G, Thomson B C, Smith N B, Johnstone P D, Bicknell N
a Kotare Bioethics , Wellington , New Zealand.
N Z Vet J. 2015 Sep;63(5):260-4. doi: 10.1080/00480169.2015.1024779. Epub 2015 Jun 15.
To determine the ability of sheep to mobilise their body reserves after being deprived of feed prior to transport for slaughter.
A total of 240 3- and 4-year-old cull ewes were held off pasture for 0, 9, 18 or 30 hours (n=60 per group) then transported 1 hour by road, unloaded and washed, held in lairage for 3 hours then slaughtered. Blood samples were collected from a subsample of 60 unfasted ewes 1 week earlier, and from all ewes at exsanguination to determine concentrations of serum metabolites indicative of adaptation to fasting. In addition, several attributes of carcass quality were measured.
At slaughter, increased time off pasture prior to transport resulted in no change in glucose concentrations in serum (p=0.140). There were differences (p<0.001) between the group fasted for 30 compared with 0 hours in mean concentrations of free fatty acids (0.98 (SD 0.32) vs. 0.58 (SD 0.23) mmol/L), β-hydroxybutyrate (0.69 (SD 0.17) vs. 0.42 (SD 0.11) mmol/L), triglycerides (0.29 (min 0.13, max 0.83) vs. 0.22 (min 0.06, max 0.96) mmol/L) and urea (10.17 (SD 1.80) vs. 6.94 (SD 2.03) mmol/L). Different periods of feed deprivation had no effect (p>0.05) on carcass weights (mean 22.7, min 13.2, max 32.9 kg) or dressing out percentages (mean 40.9, min 27, max 49%). Meat ultimate pH was unaffected (p>0.05) by the period of feed deprivation but meat became darker (p<0.05) and had reduced redness (p<0.001) with increasing time off feed.
The results suggest that sheep in variable body condition adapted to the periods of feed deprivation by mobilising their energy reserves without any evidence of metabolic depletion (e.g. depleted blood glucose or high meat pH). However, being deprived of feed they probably experience a degree of hunger.
确定绵羊在运输屠宰前禁食后动用身体储备的能力。
将总共240只3至4岁的淘汰母羊在牧场外分别禁食0、9、18或30小时（每组n = 60只），然后通过公路运输1小时，卸载并清洗，在牲畜栏中饲养3小时后屠宰。在1周前从60只未禁食的母羊子样本中采集血样，并在放血时从所有母羊采集血样，以测定指示禁食适应情况的血清代谢物浓度。此外，还测量了胴体品质的几个属性。
屠宰时，运输前在牧场外禁食时间增加，血清葡萄糖浓度无变化（p = 0.140）。禁食30小时组与禁食0小时组相比，游离脂肪酸平均浓度（0.98（标准差0.32）对0.58（标准差0.23）mmol/L）、β-羟基丁酸（0.69（标准差0.17）对0.42（标准差0.11）mmol/L）、甘油三酯（0.29（最小值0.13，最大值0.83）对0.22（最小值0.06，最大值0.96）mmol/L）和尿素（10.17（标准差1.80）对6.94（标准差2.03）mmol/L）存在差异（p < 0.001）。不同的禁食期对胴体重量（平均22.7，最小值13.2，最大值32.9 kg）或屠宰率（平均40.9，最小值27，最大值49%）没有影响（p > 0.05）。肉的最终pH值不受禁食期的影响（p > 0.05），但随着禁食时间增加，肉色变深（p < 0.05）且红色度降低（p < 0.001）。
结果表明，身体状况各异的绵羊通过动用能量储备适应了禁食期，没有任何代谢耗竭的迹象（如血糖耗尽或肉的pH值过高）。然而，由于被剥夺了食物，它们可能会经历一定程度的饥饿。
