Keywords Infrared image, housing environment, heat exchange, economic evaluation, egg production Submitted: February/2011 Approved: October/2012 ABSTRACT Infrared thermographic images were used to evaluate the effect of the exposure of layers to cold. In this trial, 540 Isa Brown® layers with an average age of 69 weeks were housed in a conventional layer house typically used in Brazil during a period of cold environmental temperatures. Environmental and heat-transference data were recorded between July 13-16, 2010. It was verified that layers under cold stress conditions lost four times more energy that the recommendations trying to maintain their body temperature. Due to their reduced feed intake capacity, hens are not capable of increasing the availability of the metabolic energy required to maintain their body temperature and egg production, consequently resulting in economic losses.

No abstract

RESUMO A cadeia produtiva da carne bovina tem evoluído nos últimos anos em direção à diferenciação de produtos de qualidade. Os atuais sistemas de produção ofertam produtos diferenciados, demandando animais de qualidade e remuneração aos produtores. Problemas de manejo e logísticas podem prejudicar a cadeia produtiva, gerando perdas de qualidade econômicas no produto final. As contusões nas carcaças representam as principais perdas no frigorífico, pois, ocasionam quedas de rendimento de carcaça, danos aos cortes comerciais, como o traseiro, lombo e a ponta de agulha e consequentemente diminuição da qualidade da carcaça. Ocasionadas no animal, as contusões são reflexo de problemas durante o manejo pré-abate, nas instalações e/ou das características dos animais. A mensuração é possível somente apenas após abate com a retirada do couro, tornando difícil caracterizá-las no momento em que ocorrem as lesões. Objetivou-se determinar os principais agentes causadores das contusões em carcaças bovinas desde o embarque na propriedade até o abate no frigorífico e as consequências na qualidade da carcaça e da carne. As soluções devem estar embasadas em leis e normativas mais rigorosas entre os órgãos governamentais e instituições, aliadas também ao pecuarista e indústria, seguidas das adequadas etapas pré-abate para que possam entregar, dessa forma, produto idôneo aos consumidores. PALAVRAS-CHAVE: contusão, distâncias, perdas no produto final

SUMMARY Meat tenderness is a major attribute for consumers worldwide. However, few studies investigate the importance of lamb meat tenderness for Brazilian consumers. This study assessed consumers’ evaluation of lamb meat with high shear forces. Eight lambs were slaughtered at 32.5±2.5kg of live weight and 5 to 6 months of age. The Longissimus dorsi muscle from both half carcasses was randomly assigned to four different postmortem processes: Tough Meat (TM), obtained by cold shortening, Fresh Meat (FM), Aging for 3 (A3) and 7 (A7) days postmortem . The variables measured were the sarcomere length, shear force (WBSF) and myofibrillar fragmentation index. We also applied the sensory analysis using affective acceptance tests with hedonic scale of nine points to measure texture, juiciness and overall quality of the meat. The postmortem processing for TM resulted in shorter sarcomere and greater shear values (p <0.05) compared to all other samples, while FM, A3 and A7, did not differ between the samples. Myofibrillar fragmentation was greater for A7 compared to TM (p <0.05), while FM and A3 showed intermediate values that did not differ between the treatments. In the sensory analysis, TM samples received significantly lower scores (p <0.01) for all attributes compared to other treatments and the attributes were not different between the post rigor processes. Consumers identified and evaluated negatively the meat samples with high WBSF. However, further studies are needed to elucidate the impact of smaller differences in WBSF, at intermediate values, on consumers’ evaluation.