van Schalkwyk S J, Hoffman L C, Cloete S W P, Mellett F D
Department of Animal Sciences, University of Stellenbosch, Private Bag XI, Matieland 7602, South Africa; Klein Karoo Agricultural Development Centre, P.O. Box 351, Oudtshoorn 6620, South Africa.
Meat Sci. 2005 Apr;69(4):647-51. doi: 10.1016/j.meatsci.2004.10.016. Epub 2004 Dec 15.
Commercially reared ostriches (n=84) were randomly allocated to one of two groups. The first group (stressed: n=38) was deprived of food for a period of 2.5 days prior to slaughter, to simulate the stress experienced by slaughter ostriches held in holding pens (lairage) at a commercial ostrich abattoir over a weekend. The second group (control: n=46) was fed normally until 24 h prior to slaughter. Initial live weight as well as hot and cold drumstick weight were independent (P>0.05) of treatment. Stressed birds lost on average (±SE) approximately three times more weight than control birds over the experimental period (-3.2±0.6 vs. -1.0±0.5 kg, respectively). Full stomach and alimentary tract weights did not differ between treatments although there was a tendency for that derived from stressed birds to have lower stomach contents. The intra-muscular (Muscularis iliofibularis) pH(f) of stressed birds was 0.22 units higher (P<0.01) than that of contemporaries in the control group 1 h post-slaughter (6.03±0.06 vs. 5.81±0.05, respectively). After 26.5 h in a refrigerated room, this difference still remained at 0.25 units (6.46±0.07 vs. 6.21±0.07, respectively; P<0.05). Post-slaughter changes in intra-muscular pH followed approximately the same trend in stressed and control birds. Intra-muscular temperature was largely independent of treatment, although there was a suggestion of a slightly higher (P=0.18) temperature in stressed birds immediately post-slaughter. Cooking loss, drip loss and shearing values were not affected (P>0.05) by the withholding of food for 2.5 days. It can thus be concluded that withholding feed from ostriches on lairage over a period of 2.5 days does not have any negative influence on the meat yield or physical quality traits thereof.
商业养殖的鸵鸟(n = 84)被随机分为两组。第一组(应激组:n = 38)在屠宰前禁食2.5天,以模拟商业鸵鸟屠宰场周末圈栏(待宰栏)中待宰鸵鸟所经历的应激。第二组(对照组:n = 46)在屠宰前24小时正常喂食。初始活重以及热、冷鸡腿重量与处理方式无关(P>0.05)。在实验期间,应激组的鸟平均(±标准误)体重损失比对照组大约多三倍(分别为-3.2±0.6千克和-1.0±0.5千克)。尽管应激组的鸟胃内容物有减少的趋势,但两组间全胃和消化道重量并无差异。应激组的鸟在屠宰后1小时,其肌内(髂胫束肌)pH(f)比对照组的同期鸟高0.22个单位(P<0.01)(分别为6.03±0.06和5.81±0.05)。在冷藏室放置26.5小时后,这种差异仍为0.25个单位(分别为6.46±0.07和6.21±0.07;P<0.05)。应激组和对照组的鸟屠宰后肌内pH的变化趋势大致相同。肌内温度在很大程度上与处理方式无关,尽管有迹象表明应激组的鸟在屠宰后即刻温度略高(P = 0.18)。禁食2.5天对烹饪损失、滴水损失和剪切值没有影响(P>0.05)。因此可以得出结论,鸵鸟在待宰栏中禁食2.5天对其肉产量或肉质特性没有任何负面影响。