Qualidade de cortes de suínos recebendo ractopamina na ração em diferentes programas alimentares = Quality of pork cuts from swine receiving ractopamine as ration in different feed programs

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 durante28 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, semractopamina, 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), agordura (QGB) e a relação carne:gordura (RCGB) da barriga. 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 cortessuínos e a restrição alimentar diminui a FB.<br><br>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 + 1factorial (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

Evaluation of different corn textures in dry grain or silage forms for piglets from 7 to 15 kg

The objective of this study was to evaluate different textures and storage forms of corn in piglet diets. Two experiments were conducted, one of which tested digestibility of nutrients and the other diet performance. In the digestibility trial, 24 crossbred (Landrace X Large White) barrows with an initial weight of 18.7 ± 1.5 kg were used. They were kept in metabolic cages in a randomized block design using the factorial arrangement 2 X 2 (type of corn - dent and flint X type of storage - moist grain silage and dry grain) and six replicates, with one animal as the experimental unit. The values of metabolizable energy (ME) obtained were 3841 kcal of ME/kg of dry matter (DM) from dry corn, 3912 kcal of ME/kg of DM from moist corn, 4022 kcal of DM from ensiled dry corn and 3928 kcal of ME/kg of DM from ensiled humidity corn. The ensilage process increases the digestibility coefficient of dry matter and crude protein and increases the digestible energy of the diets, independent of the process form. The type of corn did not influence these variables. In the performance trial, 60 barrows (initial weight of 6.5 ± 1.5 kg) of the same stock were used during 28 days of post-weaning distributed in the same experimental design, with five replicates and three animals as the experimental unit. The treatments did not influence the daily weigh gain or the daily feed intake. The dentate corn and the ensilage process decreased the feed conversion of the independent form (no significant interaction). The substitution of dry for ensilage corn increased the digestibility of the nutrients in the diets and the feed conversion of the piglets from 7 to 15 kg. Dentate corn promotes best feed conversion in this phase

Performance and carcass characteristics of swine at 50 kg fed diets with different energy levels and reduced levels of crude protein Desempenho e características de carcaça de suínos aos 50 kg recebendo rações com diferentes níveis de energia e reduzido teor de proteína bruta

The aim of this work was to evaluate the effects of different levels of metabolic energy (ME) in diets with a reduced level of crude protein (CP) on the performance and carcass characteristics of growing swine. Thirty-two high-performance barrows (initial weight of 22.5 ± 1.43 kg and final weight of 50.81 ± 2.54 kg) were distributed in a randomized block design with four treatments (three levels of ME - 3,060, 3,230 and 3,400 kcal/kg - in diets with 14% CP, and one control treatment with 3,230 kcal ME/kg and 18% CP) and four replicates. The diets were formulated with a true digestible basis of amino acids present in the feed, with methionine and threonine concentrations corrected as a function of lysine levels. The animals were slaughtered and their carcasses were studied. The ME levels did not affect the average weight gain, the feed:gain ratio, the backfat thickness or the loin eye area. A higher carcass yield and a higher carcass meat:fat ratio were observed in the animals that received the 3,230 and 3,060 kcal/kg ME levels. Compared to the control treatment, only the 3,400 kcal/kg ME level had a lower average daily feed intake. It is concluded that the CP level in diet should be reduced from 18% to 14% and the metabolizable energy level should be increased, thus reducing the feed intake and increasing the carcass meat:fat ratio without affecting the animal weight gain.Objetivou-se, neste trabalho, avaliar diferentes níveis de energia metabolizável (EM) em rações com reduzido teor de proteína bruta (PB) através do desempenho e características de carcaça de suínos em crescimento. Foram utilizados 32 suínos machos castrados de elevado ganho de peso (peso inicial de 22,5 ± 1,43 kg e final de 50,81 ± 2,54 kg), distribuídos em delineamento de blocos casualizados, com quatro tratamentos (três níveis de EM - 3060, 3230 e 3400 kcal/kg - em rações com 14% PB e um tratamento controle com 3230 kcal EM/kg e 18% de PB) e quatro repetições. As rações foram formuladas com base na digestibilidade verdadeira dos aminoácidos presentes nos alimentos, sendo a metionina e a treonina corrigidas em função dos níveis de lisina. Os animais foram abatidos e tiveram suas carcaças estudadas. Os níveis de EM não afetaram o ganho de peso médio diário, a conversão alimentar, a espessura de toucinho e a área de olho de lombo. Observou-se maior rendimento e relação carne:gordura na carcaça dos animais que receberam os níveis de 3230 e 3060 kcal EM, respectivamente. Comparado ao controle, apenas o nível de 3400 kcal/kg EM reduziu o consumo de ração médio diário. Conclui-se que o teor de PB da ração para suínos em crescimento pode ser reduzido de 18% para 14% e o nível de energia aumentado, propiciando menor consumo e maior relação carne: gordura sem afetar o ganho de peso dos animai

Características da carcaça e viabilidade econômica do uso de cloridrato de ractopamina para suínos em terminação com alimentação à vontade ou restrita Carcass characteristics and economic viability of the use of ractopamine for finishing swine with ad libitum or restricted feeding

O objetivo neste trabalho foi avaliar a suplementação de 5ppm de ractopamina (RAC) na ração, associada ou não à restrição alimentar, sobre as características da carcaça de suínos em terminação e a viabilidade econômica do seu uso. Foram utilizados 30 suínos machos castrados, Agroceres-PIC (peso vivo de 107,2&plusmn;6,2kg), recebendo as dietas experimentais durante os 28 dias que antecederam o abate. Foi utilizado um delineamento em blocos casualizados em esquema fatorial 2 x 2 + 1 (com ou sem RAC em rações com 1,04% de lisina total; à vontade ou restrição alimentar de 15%; e um tratamento adicional - controle - fornecido à vontade, sem RAC, contendo 0,8% de lisina total - ração padrão), totalizando cinco tratamentos e seis repetições. A adição da RAC por si só aumentou a área de olho de lombo, a porcentagem de carne e a relação carne:gordura na carcaça, o índice de bonificação, a receita bruta e a receita líquida da produção e reduziu a espessura de toucinho dos animais. Quando associada à restrição alimentar, a RAC diminuiu a porcentagem de gordura na carcaça. Comparado à ração controle, a RAC aumentou o rendimento da carcaça, a porcentagem de carne na carcaça e a receita bruta paga ao produtor e reduziu a espessura de toucinho. Quando associada à restrição alimentar, diminuiu a porcentagem de gordura e aumentou a relação carne:gordura na carcaça e o índice de bonificação. Assim, a suplementação com 5ppm de RAC, associada ou não à restrição alimentar, melhora as características da carcaça e viabiliza economicamente a produção.The objective of this research was to evaluate the supplementation of 5ppm of ractopamine (RAC), associated or not with feed restriction, on carcass characteristics on finishing pigs and the economic viability of its use. Thirty hybrid barrows (life weight of 107.2&plusmn;6.2kg), receiving the experimental diets during 28 days before the slaughter. A randomized blocks design in factorial scheme 2 x 2 + 1 (with or without RAC in diets with 1.04% of total lysine; ad libitum or feed restriction of 15% and an additional treatment - control - ad libitum, without RAC containing 0.8% of lysine - standard diet), totalizing five treatments and six replicates. The addiction of RAC per se increased the loin eye area, the meat percentage, the carcass meat:fat ratio, the allowance index, the gross earnings and the production net earnings and decreased the animals backfat thickness. When associated with feed restriction, the RAC decreased the carcass fat percentage. Compared to standard diet, the RAC increased the carcass yield, the carcass meat percentage and the allowance index paid to the producer and decreased the backfat thickness. The RAC associated at the feed restriction decreased the fat carcass percentage and increased the carcass meat:fat ratio and the gross earnings. Thus, the supplementation with 5ppm of RAC, associated or no at the feed restriction, improves the carcass characteristics and the economic viability of production

Digestible and metabolizable energy of crude glycerin for finishing pigs

The aim of this study was to determine the values of apparent digestible energy (DE) and metabolizable energy (ME) for crude glycerin derived of biodiesel based on pork fat for finishing pigs. The diets consisted of a basal diet and four levels of crude glycerin (0, 5, 10 and 15%). Twelve pigs were housed individually in metabolic cages and after seven days of adaptation, total collections of urine and feces for four consecutive days were performed. Gross energy (GE) of crude glycerin, diets, urine and fecal samples from each animal was determined. The crude glycerin used in this experiment presented 74.74% glycerin and 6,500 kcal kg-1 gross energy. The values of digestible energy (DE) and metabolizable energy (ME) were estimated by difference in the DE, and content of the basal diet was subtracted from the test diets containing the ingredient. The amount of GE, DE and ME for finishing pigs was 6,500, 5,839 and 5,509 kcal kg-1, respectively, with a coefficient of 91.0% of DE and 94.0% of ME. The energy of crude glycerin is based on the levels of fatty acids and GE depends on the concentration of fatty acids and glycerin, ME being a percentage of GE averaging is 84.75%.

Ractopamine for finishing barrows fed restricted or ad libitum diets: performance and nitrogen balance

Supplementation of 5 ppm of ractopamine, associated or not to feed restriction in diets with a high total lysine content (1.04%) was evaluated on performance and nitrogen balance. In experiment 1, 60 hybrid castrated male swine (76.2 &plusmn; 2.3 kg) were housed in pairs according to a randomized complete block design in a factorial treatment arrangement (2 &#215;2 + 1) with or without ractopamine supplementation, two forms of feeding, ad libitum and feed restriction with 1.04% lysine, and an additional treatment (control), with ad libitum feed without ractopamine with 0.8% lysine, amounting to five treatments and six replications. The final live weight, daily weight gain, daily feed intake and feed conversion for 28 days were evaluated. There were improvements in supplementation with ractopamine for final live weight, daily weight gain and feed conversion. The ad libitum feeding improved both final live weight and daily weight gain compared with ractopamine. Compared with the control, there was a decrease in feed conversion with ractopamine supplementation and improvement for final weight (FW) in the treatment with the ractopamine and ad libitum feed. In experiment 2, 30 hybrid castrated male swine (74.1 &plusmn; 2.5 kg) were housed in metabolism cages and fed the same experimental treatments to evaluate the percentages of absorbed nitrogen (Nabs), retained nitrogen (Nret), nitrogen retained from the absorbed nitrogen (Nret/Nabs) and the plasma urea concentration at 14 and 28 days. At 14 days, there was an increase in the Nret/Nabs and plasma urea concentration with ractopamine supplementation. Compared with the control, there was a decrease in the plasma urea concentration for feed restriction with ractopamine. At 28 days, there was an increase in the Nret/Nabs with ractopamine supplementation. Thus supplementation with 5 ppm ractopamine improved the performance and efficiency of swine nitrogen use. Feed restriction interfered negatively in weight gain, but it improved the efficiency of the nitrogen use of barrows