ENRIQUECIMENTO AMBIENTAL E PROTOCOLOS DE IMUNOCASTRAÇÃO PARA SUÍNOS

RESUMO

Os objetivos com o presente estudo foram avaliar o uso do enriquecimento ambiental e de pro-tocolos de imunocastração sobre os aspectos de bem-estar animal, desempenho, qualidade de carcaça e carne de suínos. O período experimental teve duração de 75 dias, variáveis mensura-das até o 40º dia do experimento foram analisadas com base em um delineamento experimental inteiramente ao acaso, com dois tratamentos, suínos alojados em baias com ou sem enriqueci-mento ambiental (CEA e SEA, respectivamente) e 12 repetições (baias com 13 animais). Vari-áveis coletadas após o 41º dia foram analisadas com base em um delineamento em esquema fatorial 2*2, com 6 repetições CEA e SEA, segunda dose de imunocastração 22 e 35 dias pré-abate. O experimento foi conduzido em uma granja comercial no Oeste de Santa Catarina. As variáveis de desempenho foram mensuradas ao final das trocas de ração. As variáveis compor-tamentais avaliadas por meio de análise de vídeos e para o registro comportamental, foi utili-zado o método focal sampling com a baia como a unidade experimental. E para as coletas de salivares, foi utilizado Salivette® (SARSTEDT AG & Co., Nürbrecht, Alemanha) e medido usando um ensaio imunofluorométrico, para mensuração do cortisol salivar, tendo o animal como unidade experimental. Os animais foram abatidos em um abatedouro comercial onde fo-ram realizadas as avaliações de carcaça e posteriormente qualidade de carne. Não houve inte-ração para as variáveis de desempenho. O enriquecimento ambiental e a imunocastração 22 dias pré-abate melhoraram a conversão alimentar e ganho de peso diário, 0,054g e 128g por unidade de ganho. Houve redução dos comportamentos negativos nos grupos enriquecidos e imunizados 35 dias, em média 40%. Os níveis de cortisol salivar não diferiram entre as variáveis avaliadas. Houve interação no peso testicular, de forma que o grupo tratado CEA35 apresentou menor valor nesta variável, e interação dos tratamentos para o escore de lesões, com menor escore no grupo CEA22. A porcentagem de carne magra e área de olho de lombo foram menores nos grupos submetidos à castração 35 dias pré-abate, independente do ambiente de criação, porém as variáveis de qualidade de carne não diferiram. Os suínos do grupo tratado CEA35 tiveram redução de comportamentos indesejados, como estereotipias, ou comportamento de monta. Além disso, a associação entre a imunocastração 22 dias pré-abate e uso de enriquecimento ambiental reduz o escore de lesões no abatedouro.

ABSTRACT

The objectives of the present study were to evaluate the use of environmental enrichment and two different immunocastration protocols on the aspects of animal welfare, performance, carcass quality and meat of male pigs. Two immunocastration protocols (castration 35 days pre-slaughter and castration 22 pre-slaughter) and two breeding environments (pens with environmental enrichment and conventional pens) were used. The experimental period lasted 75 days and the variables measured up to the 40th day of the experiment (for not having started the 2nd stage of immunocastration) were analyzed based on an experimental design entirely at random, with two treatments, with or without environmental enrichment (CEA and SEA, respectively) and 12 repetitions (stalls with 13 animals). Variables collected after the 41st day (after the second dose of immunocastration in the anticipated group) were analyzed based on a 2 * 2 factorial design, two ages of immunocastration, 35 and 22 days before slaughter and two production environments, with and without environmental enrichment (CEA35, CEA22 and SEA35, SEA22), with six replicates per treatment. The experiment was carried out in a commercial farm in the west of Santa Catarina. The performance variables were measured at the end of the feed changes. The behavioral variables evaluated by means of video analysis and for the behavioral recording, the focal sampling method with the stall was used as the experimental unit. And for salivary collections, Salivette ® (SARSTEDT AG & Co., Nürbrecht, Germany) was used and measured using an immunofluorometric assay, to measure salivary cortisol, with the animal as an experimental unit. The animals were slaughtered in a commercial slaughterhouse where carcass and meat quality evaluations were carried out. There was no interaction for the performance variables. Environmental enrichment and immunocastration 22 days before slaughter improved feed conversion. There was a reduction in negative behaviors in the enriched and immunized groups in advance. The levels of cortisol sali-var did not differ between the variables evaluated. There was an interaction in testicular weight, so that the immunocastrated 35 days pre-slaughter had a lower value in this variable only in the enriched environment and interaction of treatments for the injury score, with a lower injury score in the enriched group, when it had the second dose of early immunocastration (CEA22). The percentage of lean meat and loin eye area was lower in the groups submitted to the anticipation of immunocastration, regardless of the rearing environment, however the meat quality variables did not differ. The immunocastration 22 days before slaughter and the use of environmental enrichment at the end improves feed conversion. Immunocastrated pigs 35 days before slaughter in an enriched environment had a reduction in undesirable behaviors, such as stereotypes or breeding behavior, also a reduction in testicular weight. In addition, the association between immunocastration 22 days before slaughter and the use of environmental enrichment reduces the score of injuries in the slaughterhouse.