The 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 point to 9.4 ppm of ractopamine). To the carcass parameters there was a quadratic effect to the carcass yield (been the minimal point to 9.5ppm of ractopamine). The parameters a*(red-blue component) and c*values (saturation index) and marbling presented a negative linear effect according to the levels of ractopamine. The fiber diameter of the L. dorsi muscle and the tonality angle index (h*) showed a positive linear effect to the levels of ractopamine. There were no effects on the other meat quality characteristics, resulting meats without PSE and DFD. The ractopamine can be used until 20 ppm with positive effects on the performance and carcass parameters, without effects on the behavior and on meat quality.

O 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.

Avaliou-se o efeito da substituição da pastagem pela silagem de rama de mandioca (SRM) sobre a produção e constituintes do leite e sobre a qualidade da gordura do leite de vacas da raça Holandesa. O delineamento experimental utilizado foi um duplo quadrado latino 4x4, e para o fator níveis de suplementação, foi usado regressão. A dieta-controle foi 50% concentrado e 50% volumoso, e as proporções de substituição do volumoso foram 0, 20, 40 e 60% com base na matéria seca. Todas as dietas eram isoprotéicas. Foram analisados: produção de leite (PL), PL corrigida a 4% (PLC), acidez, gordura (%), densidade, proteína, lactose, sólidos totais, contagem de células somáticas (CCS), ureia e perfil dos ácidos graxos da gordura do leite. Houve efeito linear decrescente da substituição do volumoso pela SRM sobre a PL, PLC e ureia no leite, e efeito (P<0,05) linear crescente sobre a concentração de ácido gama linolênico e ácido palmítico. A acidez, densidade, proteína, gordura, lactose, sólidos totais, CCS e demais ácidos graxos da gordura do leite permaneceram inalterados com a incorporação da SRM na dieta.

The effect of a partial substitution of pasture for cassava foliage silage (CFS) on milk production and composition on fat quality of Holstein cow milk was studied using a replicated 4 X 4 Latin square design with four treatments. Regression was used for the comparison of nutrition levels. The control diet contained 50% pasture and 50% concentrate on a dry matter basis. The substitution levels of pasture for CFS were 0, 20, 40, or 60% of the forage dry matter. All diets were isonitrogenous. The analyzed parameters were: milk production (MP); 4% fat-corrected milk production (FCM); acidity; density; concentrations of fat, protein, lactose, urea, and total solids; somatic cell counts (SCC), and milk fatty acids profile. There was a linear decrease effect (P<0.05) in MP, FCM, and urea content with increasing levels of CFS in the diet. Concentrations of gamma linolenic and palmitic acids in milk fat linearly increased (P<0.05) with higher proportions of CFS in the diet. Other contents of milk fatty acids remained similar among treatments as well as acidity; density; concentrations of protein, fat, lactose, and total solids; and SCC.

This study aimed to determine the fatty acid and chemical composition and cholesterol concentration of horsemeat, and to evaluate its taste acceptability by the Brazilian population. Horsemeat samples (M. longissimus dorsi) were obtained from a Paraná State slaughterhouse. The chemical composition revealed a low lipid (2.9%) and high protein content (22.5%). The concentrations of the nutritionally important fatty acids, arachidonic acid (AA, 20:4n-6) and eicosapentaenoic acid (EPA, 20:5n-3), were 2.97% and 0.43%, respectively. The polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) ratio was 0.97, which is within the recommended range. The cholesterol concentration of 40.5 mg/100 g is lower than that of other meat such as chicken, beef, mutton and pork. The sensory evaluation revealed excellent acceptability.

This study was carried out to evaluate the effect of a luteinizing hormone-releasing hormone (LHRH) fusion protein vaccine vs. surgical castration on the chemical composition and fatty acid profile of beef cattle (Bos indicus) slaughtered at three years of age. Thirty bulls (Nellore-cross) were divided into three groups: immunized against LHRH fusion protein, castrated or left intact (control). These animals were 24 months old at the initiation of the study and ranged on Brachiaria grass in Mato Grosso, Brazil. Meat of intact bulls presented a lower fat content compared to castrated or surgically castrated animals. For the immunized and surgically castrated animals there were differences in fat and cholesterol concentrations. Although the fatty acid profiles of the three treatments were similar in composition, there were differences in the concentrations of some fatty acids (miristic, C14:0; stearic, C18:0; linolenic, C18:3n-3; and eicosapentaenoic, C22:5n-3). Meat samples of surgically castrated animals had less polyunsaturated (PUFA) and monounsaturated (MUFA) fatty acids (8.2 and 37.7%, respectively), higher saturated (SFA) fatty acids (52.2%) and a lower PUFA/SFA ratio (0.16) and were different compared to intact and immunized bulls. The PUFA/SFA ratio increased as the fat content decreased. On the other hand, surgically castrated bulls had a higher lipid and lower cholesterol contents. It is concluded that immunization against LHRH using new recombinant LHRH fusion proteins could be an alternative to physical castration to improve carcass quality in cattle production.