Hadley P J, Holder J S, Hinton M H
Meat Hygiene Service, Central England Regional Office, Tettenhall, Wolverhampton.
Vet Rec. 1997 May 31;140(22):570-4. doi: 10.1136/vr.140.22.570.
The fleece of sheep becomes soiled primarily on the abdomen and on the legs. A five-category scoring scale for soiling of the fleece was defined, with score 1 being clean and dry and score 5 being wet and heavily soiled with faecal material. Twenty sheep with each fleece score were slaughtered and dressed on a commercial 'inverted' slaughter line. Swab samples were taken from the shoulder and the abdomen of the carcases immediately after skinning, and total viable counts and the numbers of Enterobacteriaceae were determined. The condition of the fleece significantly affected the microbial load on these parts of the dressed carcase, with the carcases derived from sheep with increasingly dirty fleeces carrying up to 1000 times more microorganisms, and a higher proportion of the carcases being contaminated with Enterobacteriaceae. Modifications to the dressing procedure were made to try to reduce carcase contamination at the shoulder. The application of bulldog clips to prevent direct contact between the fleece and the underlying muscles resulted in higher counts on carcases with a fleece score of 3, probably owing to contamination from the hands of the slaughterman and the problems with ensuring that the clips were in place before contamination had occurred. Delaying the skinning of the shoulder until later in the pelt removal process achieved worthwhile reductions in the contamination of the shoulder of carcases with a fleece score of 4, although the total viable counts were still higher than carcases with a score of 3.
绵羊的羊毛主要在腹部和腿部弄脏。定义了一个用于评估羊毛弄脏程度的五级评分量表，1分表示干净干燥，5分表示潮湿且被粪便严重污染。对每只羊毛评分为各个等级的20只绵羊在商业“倒置”屠宰线上进行屠宰和去毛处理。剥皮后立即从胴体的肩部和腹部采集拭子样本，测定总活菌数和肠杆菌科细菌数量。羊毛的状况显著影响去毛后胴体这些部位的微生物负荷，羊毛越脏的绵羊的胴体携带的微生物数量最多可达1000倍，且有更高比例的胴体被肠杆菌科细菌污染。对去毛程序进行了修改，试图减少肩部胴体的污染。使用弹簧夹防止羊毛与下层肌肉直接接触，但对于羊毛评分为3分的胴体，其菌数反而增加，这可能是由于屠宰工人的手造成的污染以及难以确保在污染发生前夹子已就位。将肩部剥皮推迟到去毛过程的后期，对于羊毛评分为4分的胴体，肩部污染有了显著减少，尽管总活菌数仍高于评分为3分的胴体。
