Ractopamina, cromo-metionina e suas combinações como aditivos modificadores do metabolismo de suínos em crescimento e terminação

Abstract

RESUMO -Objetivou-se neste estudo avaliar o efeito da adição de ractopamina, cromo-metionina e suas combinações em dietas para suínos em crescimento e terminação sobre o desempenho, as características de carcaça e a qualidade da carne.Sessenta e quatro suínos da linhagem Topigs, com peso inicial de 26,56 ± 3,11 kg, foram distribuídos em delineamento experimental de blocos casualizados em esquema fatorial 2 × 2, com dois níveis de ractopamina (0 e 5 ppm) e dois níveis de cromo-metionina (0 e 400 ppb), totalizando quatro dietas com oito repetições (blocos) por dieta. Em cada uma das três fases, crescimento 1 (de 26,56 kg aos 50,51 kg), crescimento 2 (de 50,51 kg aos 70,32 kg) e terminação (de 70,32 kg aos 114,80 kg), os animais receberam rações fareladas e água à vontade. Ao atingirem o peso vivo de 114,80 ± 4,98 kg, os animais foram abatidos e as carcaças avaliadas quanto ao rendimento de carcaça fria, ao comprimento de carcaça, à espessura de toucinho, à área de olho-de-lombo e à relação gordura:carne. Amostras do músculo longissimus dorsi foram retiradas para mensurações de cor, pH final e perda de peso por gotejamento. A suplementação de ractopamina melhorou a conversão alimentar, o rendimento de carcaça fria, a área de olho-de-lombo, a relação gordura:carne e a perda de peso por gotejamento e reduziu os teores de vermelho e amarelo da carne. O cromo-metionina, embora tenha ocasionado redução no consumo diário de ração, não altera as características de desempenho e de carcaça nem a qualidade da carne dos suínos. A suplementação de ractopamina associada a cromo-metionina não afeta o desempenho nem as características de carcaça e qualidade da carne dos animais.Palavras-chave: agonista beta-adrenérgico, carcaça, carne, desempenho, nutrição Ractopamine, chromium-methionine and their combinations as metabolism modifier feed additives of growing and finishing pigs ABSTRACT -The purpose of this study was to evaluate the effect of ractopamine and chromium-methionine additions and their combinations in diets for growing and finishing swines on performance, carcass traits and meat quality. Sixty-fourTopigs line swines at 26.56 ± 3.11 kg initial body weight were distributed in a randomized block experimental design in a 2 × 2 factorial scheme with two levels of ractopamine (0 and 5 ppm) and two levels of chromium-methionine (0 and 400 ppb), totaling four diets with eight replications (blocks) per diet. In each one of the three following phases, growing 1 (from 26.56 kg to 50.51 kg), growing 2 (from 50.51 kg to 70.32 kg) and finishing (from 70.32 kg to 114.80 kg), meal rations and water were given ad libitum to animals.When pigs reached 114.80 ± 4.98 kg body weight, they were slaughtered and carcasses were evaluated regarded to cold carcass yield, carcass length, backfat thickness, loin eye area and fat:meat ratio.Samples of longissimus dorsi muscle were taken to measure colour, final pH and drip loss. Supplementation of ractopamine improved feed conversion, cold carcass yield, loin eye area, fat:meat ratio and drip loss,...

Chromium and energy restriction as substitutes for ractopamine in finishing gilts diet

“…The effects of chromium supplementation are inconsistent, ranging from reduced feed intake in pigs fed chromium-containing diets (ALMEIDA et al, 2010), increased consumption (LIEN et al, 2001;LI et al, 2013) to no effects (MATTHEWS et al, 2006;WANG et al, 2009;SALES & JANCIK, 2011;PERES et al, 2014), as observed in this study.…”

Substitution of ractopamine by safflower or coconut oil as an additive in finishing pig diets

“…Ractopamine treatments resulted in higher REA values (P<0.05), with a similar effect observed in animals supplemented with coconut oil and safflower oil. ALMEIDA et al (2010) reported that increased REA is associated with increased protein synthesis in skeletal muscles and decreased amino acid catabolism. This response associated with ractopamine supplementation may be correlated with increased REA in pigs, suggesting that ractopamine supplementation results in carcasses with increased percentages of lean meat, decreased lipid synthesis in adipose tissue, and increased protein synthesis in muscles.…”

Net energy and ractopamine levels for barrows weighing 70 to 100kg

“…This absence of effect may be related to the range of body weights (70-100kg) in the experimental period, as prior research has demonstrated the benefits of ractopamine addition to the diets of pigs weighing over 100kg at slaughter time, particularly in terms of weight gain (CORASSA et al, 2009) and feed conversion (ALMEIDA et al, 2010). Genotypic features may be another reason why ractopamine did not affect performance, since variability in the genetic materials employed in different studies may affect the variables evaluated (HINSON et al, 2011).…”

“…Ractopamine has been shown to improve performance and carcass characteristics (CORASSA et al, 2009) without affecting meat quality (ALMEIDA et al, 2010), while increasing daily weight gain, improving feed conversion, and reducing back-fat thickness, and increasing ribeye area, meat percentage, and carcass meat-to-fat ratios.…”