RESUMO -Este trabalho foi realizado com o objetivo de avaliar o efeito da adição de ractopamina na ração sobre a qualidade da carne de suínos dos genótipos halotano homozigoto dominante (Hal NN ) e heterozigoto (Hal Nn ). Durante o experimento (21 dias), 24 suínos machos castrados e 12 fêmeas (metade de cada genótipo) com peso médio inicial de 72,6 kg de PV foram avaliados segundo delineamento experimental em blocos casualizados, em arranjo fatorial 2 x 2 x 2 (dois genótipos halotano; duas rações: controle e com adição de 10 ppm de ractopamina; e dois sexos: machos castrados e fêmeas). A análise do DNA genômico foi realizada por intermédio das técnicas de PCR-RLPC. A avaliação da qualidade da carne foi realizada no músculo Longissimus dorsi e o pH da carne foi medido 45 minutos (pH inicial) e 24 horas após o abate (pH final). Avaliaram-se a perda de água por gotejamento durante o degelo e a cocção, a cor da carne, o grau de marmoreio e a maciez objetiva. Não houve interação genótipo × ractopamina para as características de qualidade da carne avaliadas. Nenhum animal do genótipo homozigoto dominante apresentou carne PSE (textura mole, cor pálida e com pouca água), ao passo que os suínos do genótipo heterozigoto apresentaram carne com 33,3% de PSE. O uso de 10 ppm de ractopamina na ração não afetou os parâmetros de qualidade da carne. Os animais do genótipo Hal Nn apresentaram carne com qualidade inferior à dos suínos Hal NN . O pH final foi menor e a incidência de carne PSE foi maior nos suínos machos castrados que nas fêmeas.Palavras-chave: carne PSE, gene halotano, qualidade da carne Effect of halothane genotype, ractopamine and sex on pork meat quality ABSTRACT -The effect of adding dietary ractopamine on meat quality of dominant homozygote (Hal NN ) and heterozygote (Hal Nn ) halothane animal genotypes was evaluated in this trial. During the experiment (21days), it was used 24 barrows and 12 gilts (half of each halothane genotype) averaging 72.6 kg initial BW. The experiment was analyzed as a randomized block with a 2 x 2 x 2 factorial arrangement (two halothane genotypes, two diets: control and with 10 ppm of ractopamine and two categories: barrows and gilts). The genomic DNA evaluation was performed by PCR-RLPC. Longissimus dorsi muscle was used for measurement of initial pH (pH45), final pH (pH24) and drip, chilling and cooking losses, meat color, marbleness, and objective softness. No effect of genotype × ractopamine interaction on meat characteristic was noticed. Meat of Hal NN animals did no show thawing loss and paler (PSE) while that of Hal Nn had about 33.3% of PSE. Ractopamine did not affect meat quality parameters. Meat of Hal Nn animals had lower quality than those of Hal NN pigs. Meat from barrows presented lower final pH and higher PSE incidence than gilts.Key Words: halothane genotype, meat quality, PSE meat IntroduçãoA carne suína é a fonte de proteína animal mais consumida no mundo. O Brasil é apontado como o país que poderá liderar a produção mundial de suínos por ser um dos maiores produtor...

The objective of this study was to evaluate the effects of ractopamine supplementation, castration method, and their interaction on the behavioral and physiological response to preslaughter stress and carcass and meat quality of 2 Piétrain genotypes. A total of 1,488 male pigs (115 ± 5 kg BW) were distributed according to a 2 × 2 × 2 factorial arrangement of treatments. The first factor was ractopamine supplementation with 2 groups of pigs (376 and 380 pigs each) receiving 7.5 mg/kg of ractopamine (RAC) or not (NRAC) in their diet during the last 28 d of the finishing period. The second factor was castration method, with 744 surgical castrates (SC) and 744 immunized males (IM), and the third factor was the genotype with 2 crossbreeds containing 50% (genotype A, GA; n = 744) or 25% (genotype B, GB; n = 744) Piétrain genetics. Surgical castration took place at 2 d of age, whereas immunization against gonadotropin-releasing factor (GnRF) was performed through 2 subcutaneous injections of GnRF analog (Improvest, 2 mL) at 10 and 4 wk before slaughter. At loading more vocal stimulation was needed by the handler to drive GB pigs forward through the farm alley (P = 0.01) and RAC-fed GB pigs through the ramp (P = 0.02). Feeding RAC to IM increased the number of fights in lairage compared with SC (P = 0.03). Feeding RAC shortened fighting bouts compared with NRAC pigs (P = 0.05). The SC-GA pigs showed a greater gastrointestinal tract temperature during unloading (P = 0.05) and lairage time (P = 0.03). Blood creatine kinase (CK) concentrations were greater (P = 0.04) in SC compared with IM, and no difference was found in the concentrations of stress hormones in urine collected postmortem. Dressing yield was greater (P = 0.01) in RAC and SC-GB pigs. Carcasses from RAC pigs and IM were leaner than those from NRAC and SC pigs (P < 0.001 and P = 0.002, respectively). Feeding RAC to IM increased drip loss in the LM (P = 0.05). Warner-Bratzler shear force values were slightly greater in the LM from RAC-GB pigs and from IM compared with SC (P = 0.01 and P < 0.001, respectively) and in the semimembranosus muscle of RAC pigs (P = 0.006). In conclusion, immunization against GnRF more than the use of Piétrain genotypes appears to be a viable alternative to the use of ractopamine, as it seems to promote production of lean carcasses without compromising animal welfare and pork quality.

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A total of 5502 piglets from 435 sows were selected for evaluation of the effect of piglet birthweight and sow parity on mortality rate (MR), growth performance, and carcass traits in pigs. Piglets were distributed into one of eight categories according to their weight (<600, g) and sows were classified according to parity (1-5). The maximum MR during lactation (day 0 to day 21) was found in category <600 g, whereas the lowest was observed in categories ≥1401 g. Pigs with greater body weight (BW) at birth were equivalently greater until 59 days of age. Average daily weight gain (ADG) was improved by increasing piglet birthweight between 0 and 21 days as indicated by a linear regression effect. After weaning, this effect was reduced up to 168 days, indicated by a quadratic, as opposed to linear, regression effect. The increase in growth rates corresponded to improved lean meat content and hot carcass weight. Increasing sow parity corresponded to a quadratic improvement of BW and ADG during lactation, but not after weaning. However, the improved pre-weaning performance was concomitant with a linear increase of within-litter BW and ADG variation. No effect of parity was observed on carcass traits. Piglet birthweight and sow parity influence litter postnatal development, mainly during early life. After weaning, these effects are less evident with a minor impact on carcass traits.

The objective of this study was to evaluate the effect of increasing doses of bacterial phytase (RONOZYME HiPhos) on performance and carcass characteristics of growing and finishing pigs. The study included 120 castrated males with initial weight of 23.21 ± 1.91 kg and 68 days of age, distributed in a randomized block design with five treatments and eight replicates with three animals each. The pigs were fed five corn-soybean meal-based diets: positive control (PC), supplemented with inorganic phosphorus and calcium; negative control (NC), with 0.13% reduction in available phosphorus and 0.11% in calcium; and three NC diets supplemented with 1,000, 2,000, and 3,000 phytase units (FYT)/kg in the feed. Compared with the NC diets without phytase, diets with 1,000, 2,000, and 3,000 FYT/kg inclusion increased the daily weight gain by +12% (quadratic, p<0.05) during the growing I period; +2.9, +2.9, and +10.5% (linear, p<0.01), respectively, during the growing II period; and +4.1, +5.1, and +8.2% (linear, p<0.001), respectively, over the entire experimental period. The daily feed intake increased by 0, +2.8, and +4.3% (linear, p<0.05), respectively, considering the entire experimental period; and the final live weight increased by +3.2, +4.2, and +6.1% (linear, p<0.001), respectively. The phytase treatments did not influence feed conversion ratio, carcass weight and yield, backfat thickness, loin depth and carcass lean meat. According to the European Carcass Classification (SEUROP), however, the animals fed the PC diet and the three phytase levels had more carcasses classified as E (between 55–60% lean meat) when compared to carcasses of pigs fed the NC. Supplementing increasing levels of phytase to a corn- and soybean meal-based diet with inorganic P and Ca reduction improved daily weight gain and feed intake of growing pigs, and such effects were maintained until slaughter age.

ResumoEste trabalho foi realizado com o objetivo de avaliar o efeito do grupo genético e grau de acabamento da carcaça sobre as perdas por descongelamento (PDES), perdas por cocção (PCOC), pH, força de cisalhamento (FC), luminosidade, frequência e diâmetros das fibras de contração lenta, metabolismo oxidativo e coloração vermelha (SO), de contração rápida, metabolismo oxidativo-glicolítico e coloração intermediária (FOG) e de contração rápida, metabolismo glicolítico e coloração branca (FG) do músculo Longissimus de bovinos terminados em confinamento. Foram avaliados os grupos NELNelore; LIN -½ Limousin + ½ Nelore e RAN -½ Red Angus + ½ Nelore abatidos com 3 ou 5 mm de espessura de gordura de cobertura. Houve interação entre o grupo genético RAN e grau de acabamento para características PDES, PCOC, pH, FC e intensidade de vermelho (a*). Os bovinos NEL tinham carnes mais escuras do que os animais mestiços, além de apresentarem maior pH final. No entanto, a carne destes bovinos apresentou menor PDES, PCOC e FC quando comparada à de bovinos mestiços. Bovinos RAN apresentaram maior frequência de fibras FOG e menor de fibras SO, além de maiores diâmetros para estas fibras. Diferenças na qualidade da carne entre grupos genéticos foram verificadas no menor grau de acabamento da carcaça. No entanto, estas diferenças deixam de existir quando o abate ocorreu com maior grau de acabamento. O grau de acabamento (3 ou 5 mm) de espessura de gordura de cobertura não teve efeito na qualidade da carne de bovinos terminados em confinamento.

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

ResumoAs definições de bem-estar animal têm sido amplamente debatidas junto à comunidade científica internacional durante as últimas décadas. A linha conceitual mais aceita trata do bem-estar animal dentro de um enfoque multidimensional, abrangendo emoções, funcionamento biológico e comportamento natural. No entanto, compreendido os conceitos, outro desafio que se apresenta é como mensurar adequadamente o bem-estar animal nas condições de campo. Neste sentido, o projeto Welfare Quality ® fornece uma compreensão muito útil dos componentes de bem-estar e de como podemos avaliá-lo em granjas comerciais e abatedouros de suínos. O objetivo deste artigo é discorrer sobre os principais conceitos científicos de bem-estar animal e sobre as formas práticas de avaliação segundo os protocolos do projeto Welfare Quality ® em suínos, identificando seus aspectos positivos e críticos. Palavras-chave: Mensurações, suinocultura, Welfare Quality ® AbstractThe concepts of animal welfare have received a wide discussion by international scientific community during the last decades. The most accepted definition consider the animal welfare like a multidimensional theme, where are involved the emotion, the biological activity and the natural behavior. However, considering the clearness of this concepts, another challenge is presented, where is questioned how we can evaluate the animal welfare in commercial systems. Thus, the Welfare Quality ® project gave the understanding about the welfare subjects and how we can to evaluate its in commercial farms and slaughterhouses. Then the main of this article is present the principal concepts and practical means to evaluate the animal welfare in swine, according the Welfare Quality ® protocols, with the identifications of the positive and critical aspects involved.