RESUMO
This study evaluated the supplementation of ractopamine associated with feeding restriction in diets with high lysine content on the composition of pork cuts. Thirty barrows (107.2 ± 6.2 kg) were utilized, receiving the experimental diets during 28 days before slaughter. The randomized block design was applied in a 2 x 2 + 1 factorial (two levels of ractopamine 0 or 5 ppm in rations with 1.03% of total lysine; ad libitum or 15% feed restriction; and a control treatment, ad libitum, without ractopamine, with 0.8% of total lysine) with six replicates. The cuts were obtained from the left chilled carcass. The tenderloin percentage (RFIL), the ham (PCPER), shoulder (PCPAL), boneless shoulder (PCSOP) and bone-in loin (PCCAR) meat percentage, the average thickness (EB), flexibility (FB), amount of meat (QCB), fat (QGB) and meat:fat ratio of the belly (RCGB) were evaluated. The ractopamine increased RFIL, PCPER, PCPAL, PCSOP, PCCAR and RCGB when compared to diets without ractopamine and 1.03% of lysine. Compared to the control, ractopamine increased PCCAR and RCGB; decreased QGB; and when associated with the feed restriction, increased PCPER. Feed restriction decreased FB. The use of ractopamine increases the meat percentage in pork cuts and feed restriction decreases FB.
Avaliou-se a suplementação de ractopamina associada à restrição alimentar em rações com elevado teor de lisina sobre a composição de cortes suínos. Foram utilizados 30 suínos machos castrados (peso 107,2 ± 6,2 kg), recebendo as dietas experimentais durante 28 dias pré-abate. Foi utilizado um delineamento em blocos casualizados em fatorial 2 x 2 + 1 (dois níveis de ractopamina 0 ou 5 ppm em rações com 1,03% de lisina total; fornecidas à vontade ou 15% de restrição, e um tratamento controle, ad libitum, sem ractopamina, contendo 0,8% de lisina total) com seis repetições. Os cortes foram obtidos da carcaça esquerda resfriada. Foram avaliados o rendimento do filezinho (RFIL), as porcentagens de carne no pernil (PCPER), a paleta (PCPAL), a sobrepaleta (PCSOP) e o carré (PCCAR) e a espessura (EB), a flexibilidade (FB), a quantidade de carne (QCB), a gordura (QGB) e a relação carne:gordura (RCGB) da barrriga. A ractopamina aumentou o RFIL, PCPER, PCPAL, PCSOP, PCCAR e RCGB quando comparada com rações sem ractopamina e 1,03% de lisina. Comparado ao controle, a ractopamina aumentou o PCCAR e a RCGB; diminuiu o QGB e, quando associada à restrição, aumentou a PCPER. A restrição diminuiu a FB. O uso de ractopamina aumenta a porcentagem de carne nos cortes suínos e a restrição alimentar diminui a FB.
RESUMO
This study evaluated the supplementation of ractopamine associated with feeding restriction in diets with high lysine content on the composition of pork cuts. Thirty barrows (107.2 ± 6.2 kg) were utilized, receiving the experimental diets during 28 days before slaughter. The randomized block design was applied in a 2 x 2 + 1 factorial (two levels of ractopamine 0 or 5 ppm in rations with 1.03% of total lysine; ad libitum or 15% feed restriction; and a control treatment, ad libitum, without ractopamine, with 0.8% of total lysine) with six replicates. The cuts were obtained from the left chilled carcass. The tenderloin percentage (RFIL), the ham (PCPER), shoulder (PCPAL), boneless shoulder (PCSOP) and bone-in loin (PCCAR) meat percentage, the average thickness (EB), flexibility (FB), amount of meat (QCB), fat (QGB) and meat:fat ratio of the belly (RCGB) were evaluated. The ractopamine increased RFIL, PCPER, PCPAL, PCSOP, PCCAR and RCGB when compared to diets without ractopamine and 1.03% of lysine. Compared to the control, ractopamine increased PCCAR and RCGB; decreased QGB; and when associated with the feed restriction, increased PCPER. Feed restriction decreased FB. The use of ractopamine increases the meat percentage in pork cuts and feed restriction decreases FB.
Avaliou-se a suplementação de ractopamina associada à restrição alimentar em rações com elevado teor de lisina sobre a composição de cortes suínos. Foram utilizados 30 suínos machos castrados (peso 107,2 ± 6,2 kg), recebendo as dietas experimentais durante 28 dias pré-abate. Foi utilizado um delineamento em blocos casualizados em fatorial 2 x 2 + 1 (dois níveis de ractopamina 0 ou 5 ppm em rações com 1,03% de lisina total; fornecidas à vontade ou 15% de restrição, e um tratamento controle, ad libitum, sem ractopamina, contendo 0,8% de lisina total) com seis repetições. Os cortes foram obtidos da carcaça esquerda resfriada. Foram avaliados o rendimento do filezinho (RFIL), as porcentagens de carne no pernil (PCPER), a paleta (PCPAL), a sobrepaleta (PCSOP) e o carré (PCCAR) e a espessura (EB), a flexibilidade (FB), a quantidade de carne (QCB), a gordura (QGB) e a relação carne:gordura (RCGB) da barrriga. A ractopamina aumentou o RFIL, PCPER, PCPAL, PCSOP, PCCAR e RCGB quando comparada com rações sem ractopamina e 1,03% de lisina. Comparado ao controle, a ractopamina aumentou o PCCAR e a RCGB; diminuiu o QGB e, quando associada à restrição, aumentou a PCPER. A restrição diminuiu a FB. O uso de ractopamina aumenta a porcentagem de carne nos cortes suínos e a restrição alimentar diminui a FB.