AVOIDING TRAUMATIC INJURIES

The presence of traumatic injuries (bruises) in dressed carcasses of slaughtered animals are quite normal. But these affect their Welfare, diminish the meat quality and bring about important economic losses (1,4). Animals to be slaughtered are transported at least once in their lives (6), during the whole commercialization chain, either by road, as it is the case of Uruguay or by different transport means (land, railway or sea). Once in the slaughterhouses, the unloading, weigh and housing in the barns take place in the pre-slaughter hours. If this handling is inappropriately carried out, the immediate consequences are the presence of bruises in different areas of the carcass and of different seriousness, decommissions of areas affected by such injuries, the losses occasioned by the so-called “dark cuts”, difficulty in the decrease of the pH required for converting the muscle into meat and the deterioration of the meat quality.(1,2,3,5) STUDIES AND EVIDENCIESThe Faculty of Veterinary of Uruguay, with the support of the National Institute of Farming Researches (INIA) and the BID (LIA 002 project), studied during the years 2002 and 2003 the critical points affecting the animal welfare in the pre-slaughter stages. The arrival and unloading of almost 500 cattle herd and over 15,000 head of cattle were observed in all exporting slaughterhouses which are authorized by the country official agency. The obtained results are summarized as follows: - 46% of the trucks transporting cattle in Uruguay date from 7 years, most of them (99%) have guillotine doors and 53% of the vehicles have rubber rollers at least on one of the door sides. Concerning the working experience of the vehicle drivers, the average was 14 years in the sector, what shows a good knowledge of cattle transport. 80% of the traveled routes were in good conditions and the average of traveled kilometers was 214. The loading facilities were considered to be good for the drivers in 80% of the cases and the average time employed for loading and unloading was 12 minutes. The assistance devices used for such a handling were the prodder in 57% of the cases, followed by screams in 40% and sticks in 35%, though, in general, more than one device was used at the same time (chart 1).-By observing the dressed carcasses during the slaughter, it was found that 55% (16 000 middle carcasses) had at least one traumatic injury (chart 2). The area of the hindquarters containing the most commercially valuable cuts had 65% of the injuries, followed by the back-lateral area which also contains highly-valued cuts, with 24% of bruises and the front area with 12% (chart 3). Out of the injured dressed carcasses, 50% showed an injury and the remaining 50% was divided into 2,3 4 or more than one bruise by middle dressed carcass observed. (chart 4). In all the areas, 20% of the injuries were of high seriousness (affecting deep muscle layers), provoking a partial or total decommission of the cut and/or change in the use of the cut or the middle carcass and the remaining 80% were injuries of low importance (chart 5).- Samples of the decommissioned tissues were taken in the different areas of the dressed carcass, oscillating between 250 and 2.000 grams. Considering an average of U$S 2.500 per ton, the country would be losing some U$S 2.000.000 dollars per year only as a result of eliminating the carcass affected areas. When adding to this the man-hours aimed at carrying out these cleaning tasks, the carcass devaluation due to the change of use, the potential loss of demanding markets and the consumer displeasure, these figures greatly multiply. CONCLUSIONSIt is imperative to address these problems from different aspects. Concerning the producing farms, it is important to train the personnel responsible for the animal handling as well as to the owner. Likewise, as far as a rational and humane handling is concerned, it is recommended not to use prodders unless it is absolutely necessary and for really short periods of time. Furthermore, sticks must not be used, nor must the facilities be overloaded with animals, facilities should be improved so that straight angles, projecting or open areas do not move animals to jump and badly-trained dogs should not be used either. During transport, it is important to train the drivers, who are the ones that unload the animals in the slaughterhouses, so that they do not use prodders, they should correctly maintain the vehicle cages and the guillotine doors so that these do not get stuck and fall on a passing animal, rubber rollers should be placed in all the truck openings and also non-slipping floor, as well as all possible protuberance which may injure the animal should be eliminated. In reference to the slaughterhouses, carry out training courses for the personnel handling the cattle, improve the facilities so that they do not have straight angles, openings, unevennesses, when possible build curved paths, not place spotlights before the animal eyes when this is addressing to the slaughter box, correctly maintain the knocking fitting and train the personnel so that the desensitization be produced with a single knock and the animal bleeding be immediately carried out.Animal welfare in the pre-slaughter stages would be thus substantially improved, meat of good quality would be produced and the economic losses entailed by these concepts should be so minimized.

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