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Inadequate pre-slaughter handling conditions can compromise animal welfare and productivity. This study aimed to evaluate the animal welfare (AW) indexes during pre-slaughter handling and quantify the carcass lesions of beef cattle submitted to different loading densities. A total of 270 Nellore cattle, at 30 months of age, from three farms were used in the study. Each farm presented a different loading density: higher density (500kg/m2), intermediate density (450kg/m2), and lower density (420kg/m2). Three shipments of cattle from each farm with 30 animals each were used in the AW analysis. Ten animals from each shipment were considered for quantification of carcass bruises. The AW indexes were classified according to the five-freedom criterion (physiological, environmental, sanitary, behavioral, and psychological). After slaughter, the carcasses were inspected in the routine line and evaluated for the presence of lesions. Statistically significant differences (p<0.001) were found for all variables studied as a function of AW and bruises. The best AW index and the lowest mean weight of lesions were found at the loading density of 450kg/m2. The highest carcass weight was observed at the loading density of 500kg/m2. Lesions were found in 100% of the animals at the loading densities of 500 and 420kg/m2. In conclusion, the best AW indexes and the smallest occurrence of bruises were verified at the loading density of 450kg/m2. This study confirmed the importance of adequate pre-slaughter handling to ensure cattle welfare and, consequently, greater profitability for producers and slaughterhouses.(AU)

Condições de manejo pré-abate inadequadas podem comprometer o bem-estar e a produtividade animal. O objetivo deste estudo foi avaliar os índices de bem-estar animal (BEA) durante o manejo pré-abate e quantificar as lesões em carcaça de bovinos submetidos às diferentes densidades de carregamento. Para isto, foram utilizados 270 bovinos Nelore, aos 30 meses de idade, provenientes de três fazendas. Cada fazenda apresentou diferente densidade de carregamento: maior densidade (500kg/m2), densidade intermediária (450kg/m2) e menor densidade (420kg/m2). Foram realizados três carregamentos de cada fazenda, compostos por 30 animais cada. Para análise do BEA e quantificação de lesões nas carcaças bovinas foram considerados 10 animais de cada carregamento. Os índices de BEA foram classificados segundo o critério das cinco liberdades (fisiológica, ambiental, sanitária, comportamental e psicológica). Após o abate, as carcaças foram inspecionadas na linha de rotina e avaliadas quanto à presença de lesões. Foram encontradas diferenças significativas (P<0,001) para todas as variáveis estudadas em função do BEA e das lesões. O melhor índice de bem-estar e o menor peso médio de lesão foi encontrado na densidade de carregamento de 450kg/m2. O maior peso da carcaça foi encontrado na densidade de carregamento de 500kg/m2. Em 100% dos animais nas densidades de carregamento de 500 e 420kg/m2 foram encontradas lesões. Pode-se concluir que a densidade de carregamento de bovino de 450kg/m2 obteve os melhores índices de bem-estar e menor ocorrência de lesões. Este estudo confirma a importância do manejo pré-abate adequado na garantia do bem-estar aos bovinos e, consequentemente, na maior rentabilidade ao produtor e ao frigorífico.(AU)

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Exposure to ochratoxin A (OTA) can lead to changes in global gene expression. This study investigated the individual expression of genes turned on and off in renal cells of chicks after different durations of exposure to dietary OTA. One hundred and eighty day-old male broiler chicks (Ross 308) were randomly assigned to a 3 × 3 factorial arrangement of treatments (3 levels of OTA: 0, 1 and 2 mg OTA/kg diet and 3 time periods: 7, 14 and 21 d). Birds were allocated to 36 pens (4 replicate pens of 5 birds each per treatment). For RNA-Sequencing analysis (RNA-Seq), kidney samples were collected weekly from 3 controls and 3 chicks fed 1 mg OTA/kg. Birds fed 2 mg OTA/kg diet were not chosen for analysis because their reduced feed intake could affect gene expression. The libraries were constructed by Illumina's TruSeq RNA protocol. NextGENe software was used for alignment and transcript quantification. Reads per kilobase of target per million tiled reads (RPKM) were used in the Binary test analysis (P < 0.05). The highest RPKM values were used as criterion for the selection of the genes described. A total of 27,638,976 50-bp RNA-Seq reads were produced over the 3 time periods. Transcripts (40,782) were assembled de novo and annotated by homology to either G. gallus or H. sapiens. The genes activated at 7 d were IL9 and TULP1, at 14 d was GHSR and at 21 d were GRK6 and GAPDH. Unlike all other genes, LOC396365 was activated during all time periods. In contrast, the genes deactivated at 7 d were SPAG4 and LOC100857131, at 14 d were LOC771469, NKX2-1, NKX2-8, FOXO1, MyHC and CLDN18 and at 21 d was XPC. The B-G gene was turned off at 7 and 21 d. All of these genes were involved in kidney toxicity. Therefore, the turning on and off responses of these genes may contribute to carcinogenic and tumorigenic effects of OTA in birds.

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