Efeito da ractopamina na performance e na fisiologia do suíno

Abstract

Beta-adrenérgico. Estresse. Gordura. ADDITIONAL KEYWORDSBeta adrenergic. Stress. Fat. RESUMOO objetivo deste trabalho foi avaliar a inclusão de diferentes níveis de ractopamina em rações de suínos em fase de terminação, durante 21 dias pré-abate, sobre as características de desempenho, carcaça, qualidade de carne e sobre parâmetros fisiológicos e sanguíneos indicadores de bem-estar. Foram utilizados 36 suínos comerciais, 18 machos castrados e 18 fêmeas, com peso médio inicial de 87,0±5,02 kg, alimentados ad libitum com rações isonutrientes, com 0, 10 e 20 ppm de ractopamina. O delineamento experimental foi em blocos casualizados, fatorial 3 x 2, com seis repetições para os parâmetros de desempenho e 12 repetições para os demais parâmetros. Houve efeito linear (p<0,05) positivo para o ganho de peso e para a conversão alimentar e efeito quadrático (ponto de mínima de 9,4 ppm de ractopamina) para o consumo de ração. Para os parâmetros de carcaça houve efeito quadrático para o rendimento de carcaça (com ponto de máxima para 9,5 ppm de ractopamina). O valor de a*(componente vermelho-verde), c*(índice de saturação) e marmoreio apresentaram efeito linear negativo. O diâmetro da fibra muscular do músculo L. dorsi e o ângulo de tonalidade (h*) apresentaram efeito linear positivo para os níveis de ractopamina. Outros parâmetros relacionados à qualidade da carne não foram influenciadas pelos tratamentos, resultando em carnes livres de PSE e DFD. A ractopamina pode ser utilizada nas rações de suínos até 20 ppm com efeitos positivos no desempenho e na carcaça, sem alterações no comportamento dos animais e comprometimentos na qualidade da carne. SUMMARYThe goal of this work was to evaluate the inclusion of different levels of ractopamine to finishing rations for swine, during 21 days before the slaughter, on the performance, carcass and meat quality parameters and on physiologic and serum characteristics related with behavior. Thirty six pigs (Large White x Landrace), 18 barrows and 18 females, weighting 87.0±5.02 kg, fed ad libitum with isonutrient rations, with 0, 10 and 20 ppm of ractopamine, were used. The experimental design was randomized blocks, factorial 3 x 2 (3 levels of ractopamine and 2 genders), with 6 repetitions for the performance parameters and 12 repetitions for the other characteristics. There were a positive linear effect (p<0.05) to the weigh gain and to the feed conversion rate and a quadratic effect to the feed consumption (been the minimal

Use of ractopamine during compensatory gain of finishing pigs on carcass and meat performance and quality

“…Vet. Zootec., v.69, n.6, p.1660-1668, 2017 conversion and final weight (P<0.05), confirming the results commonly found in experiments using this beta-adrenergic agonist (Agostini et al, 2011).…”

“…Considering treatments with and without ractopamine on carcass characteristics, the results validate the best effects obtained in the performance, confirming the role of ractopamine as an enhancer of the carcass characteristics (Agostini et al, 2011;Campos et al, 2013).…”

“…Another effect associated with this higher retention of water and the reduction of ethereal extract in the meat (P<0.07) was the percentage of crude protein in this tissue (P<0.02), which presented a lower result for the ractopamine-treated groups. One of the principles of action of this additive is an increase in muscle mass, which is accompanied by greater water retention and fat reduction (mainly subcutaneous), justifying the observed results (Almeida et al, 2010;Rossi et al, 2010;Agostini et al, 2011). Rossi et al (2010) treated castrated male pigs and finishing females with ractopamine rations (0, 10 and 20ppm) and verified that the use of the additive increased the moisture concentrations in the L. thoracis muscle and decreased the amount of fat in the meat.…”

“…The ractopamine response depends on the dose used (Agostini et al 2011) and dietary nutritional inputs, mainly crude protein and amino acids. However, studies on the association of ractopamine with compensatory gain are rather scarce and relatively old.…”

“…In this context, there are several classic procedures in the literature and even applied in practice that meet these principles including, among others, the food restriction followed by the compensatory gain (Purslow et al, 2012) and the use of ractopamine (Bridi et al, 2006;Agostini et al, 2011).…”