O. A. Dalla Costa

Meat quality of swine supplemented with ractopamine under commercial conditions in Brazil.

Commercial crossbred barrows and gilts (n = 340) were used to study the effects of different dietary inclusions of ractopamine hydrochloride (RAC) on quality of LM and semimembranosus muscle (SM). Pigs were blocked by BW (107.3 ± 0.76 kg) and allotted to gender-specific pens (10 to 12 pigs/pen), and within blocks, pens of barrows or gilts (10 pens/treatment) were randomly assigned to 1 of 3 dietary RAC inclusions (0, 5, or 10 mg/kg) fed during the last 28 d before slaughter. Initial (45-min) and ultimate (24-h) pH and temperature were measured in LM and SM. Visual and instrumental [lightness (L*), redness (a*), and yellowness (b*) values] color as well as drip loss percentages were measured in both muscles after the 24-h chilling period at 1 to 4 °C. The LM was also evaluated for marbling, and samples of the LM were used to measure intramuscular fat (IMF) content, cooking losses, and Warner-Bratzler shear force (WBSF). Pork quality characteristics of the LM (P ≥ 0.227) and SM (P ≥ 0.082) did not differ between barrows and gilts. Furthermore, neither pH nor temperature of the LM (P ≥ 0.164) or SM (P ≥ 0.284) was affected by feeding pigs RAC. The LM from pigs fed 10 mg/kg of RAC received lesser (P = 0.032) subjective color scores than LM from pigs fed 0 and 5 mg/kg of RAC, and LM from pigs fed 10 mg/kg of RAC was less (P = 0.037) red than LM from pigs fed 0 mg/kg of RAC. In addition, SM from pigs fed 10 mg/kg of RAC had lesser (P ≤ 0.015) a* and b* values than pork from control-fed pigs; however, L* values for LM and SM were not (P ≥ 0.081) affected by dietary RAC. Drip loss percentages of the LM were similar (P = 0.815) among RAC treatments, but the SM from RAC-fed pigs had smaller (P = 0.020) drip loss percentages than SM from pigs fed 0 mg/kg of RAC. Marbling scores and IMF content of the LM did not (P ≥ 0.133) differ among RAC treatments; however, WBSF values were greater (P = 0.005) for LM chops from pigs fed 10 mg/kg than chops from pigs fed 0 and 5 mg/kg of RAC. Even though feeding barrows and gilts 10 mg/kg of dietary RAC reduced (P = 0.050) cooking losses of LM chops compared with feeding 5 mg/kg of RAC, including 10 mg/kg of RAC in the diet of finishing pigs reduced pork tenderness. Therefore, results from this study support the recommendation that including 5 mg/kg of RAC in finishing diets should improve live pig performance without detrimental effects on fresh pork quality and cooked pork palatability.

Fatores de risco associados aos problemas dos leitões na fase de creche em rebanhos da região Sul do Brasil

Epidemiological essay was carried out in 65 herds of southern Brazil, with the objective to identify risk factors that better explain the occurrence of problems with the pigs during post-weaning phase. In each herd, a batch of pigs was followed during the first three post-weaning weeks, when variables like building conditions, nutrition, management, environment and health were taken into account. Descriptive and multivariate methods had been used to analyze the data. Target variable used to describe pig problems during post-weaning phase had been: weight daily gain, weight coefficient of variation at 21 days post-weaning, occurrence of diarrhea in the batch, mortality rate and the medicine use dressings against the diarrhea. With the help of these variables a synthetic variable was created for discriminating the farms in three categories: good, intermediate and bad. Among explicative variables, 10 risk factors had been selected as more important, making it possible to identify farms with high trend to present problems during post-weaning phase. One concludes that in many herds of the south region of Brazil some risk factors exist that favor the occurrence of problems with the pigs during the weaning phase, some of as consequence of others from maternity phase.

Stress susceptibility in pigs supplemented with ractopamine.

Ractopamine is a β-adrenergic agonist used as an energy repartitioning agent in the diets of finishing pigs. Most ractopamine studies are limited to evaluations of growth performance and meat quality, and there is little information on the effects of this additive on the behavior and welfare of pigs. Therefore, the objective of this study was to evaluate various indicators of stress caused by feeding diets containing ractopamine. One hundred seventy barrows and 170 gilts weighing 107.3 kg were allocated to 30 pens with 10 to 12 barrows or gilts per pen. Pigs were offered 1 of the 3 dietary treatments (0, 5, or 10 mg ractopamine/kg) for 28 d with 5 barrow pens and 5 gilt pens per treatment. Pigs were evaluated for behavior 3 d per week 1 wk before the initiation of the experiment and throughout the experiment. Each pig was classified into 1 of the 13 activities (drinking water, lying alone, lying in clusters, standing, nosing pig, sitting, feeding, biting pig, walking, exploring, running away, playing, and mounting pen mates) and also grouped into 1 of the 3 categories (calm, moving, and feeding themselves) based on those activities. At the end of the experiment, 3 pigs from each pen were slaughtered, and blood samples were collected during exsanguination to determine physiological indicators of stress (cortisol, lactate, and creatine-kinase enzymes). The incidence of skin and carcass lesions was determined at shoulder, loin, and ham. Ractopamine had no effect (P > 0.05) on pig behavior, total number of skin and carcass lesions, or blood concentrations of cortisol or lactate. However, there was an increase (P < 0.05) of creatine kinase concentrations in pigs receiving ractopamine-supplemented feed. This finding is consistent with the concept that ractopamine may cause muscular disorders, and this warrants further investigation.

Ease of handling, physiological response, skin lesions and meat quality in pigs transported in two truck types

El objetivo del trabajo fue estudiar los efectos del sistema de carga y descarga de camiones de dos pisos en el comportamiento, parametros fisiologicos (cortisol, lactato, creatina quinasa [CK], lesiones en la piel y la calidad de carne de los cerdos). Para ello, 1.728 cerdos fueron transportados a una planta faenadora de carnes utilizando dos camiones de dos pisos con diferentes sistemas, uno con piso hidraulico (HD) para el carga y descarga desde la planta superior, y otro con piso superior fijo (FD), accesible solo por medio de rampas de carga y descarga. El uso de HD resulto en una mayor facilidad y un menor tiempo de carga (P 0,05). Por tanto, se puede concluir que el uso de modelos de camiones equipados con piso hidraulico puede ser recomendado para aumentar la facilidad de manipulacion de los cerdos durante la carga, y por consiguiente, reducir la mano de obra de los trabajadores y mejorar el bienestar animal

Estimativa dos índices de pneumonia, pela tosse, e de rinite atrófica, por espirros, em suínos

A study in 64 swine herds was carried out in order to estimate the pneumonia index (PI) and the atrophic rhinitis index (ARI) through the quantification of coughing and sneezing in growing-finishing pigs. In each herd, 60 pigs were evaluated from lodging in the growing-finishing phase up to slaughter. The amount of coughing and sneezing episodes was counted in four opportunities (30, 50 and 80 days after lodging, and three days before slaughter). In each opportunity three counts of two minutes each were made and the percentage of coughing and sneezing was calculated by the average of the three counts in relation to the batch size. At slaughter, for all pig-batches the frequency and severity of lung consolidation and atrophic rinithis were determined and scored. All data were submitted to the Pearson correlation and to the simple regression analyses of the PIe in relationship to the percentage of coughing and ARIe in relationship to the percentage of sneezing. The resulting equation were: PI estimated = 0.35 + (0.11 ´ % of coughing) with R2 = 0.45, and ARI estimated = 0.36 + (0.065 ´ % of sneezing) with R2 = 0.36. It is concluded that the quantification of coughing and sneezing can be used to estimate ARI and PI indexes in growing-finishing pigs.

Fatores de risco associados ao desempenho reprodutivo da fêmea suína

Durante um ano foi realizado um estudo epidemiologico em 10 sistemas de producao de suinos (produtores de leitoes ou ciclo completo), com o objetivo de investigar os fatores de risco que melhor explicam as variacoes na produtividade da femea suina. Foi aplicado um questionario para obtencao de informacoes relacionadas a genetica, sanidade, nutricao, instalacoes e manejo. As respostas envolveram 271 femeas. Elas foram submetidas a procedimentos estatisticos de analise descritiva, analise de correspondencia multipla e classificacao hierarquica ascendente das femeas. Dessas, 236 (87,1%) pariram em media 11,4± 2,8 leitoes, 31 (11,4%) apresentaram retorno ao estro, 3 (1,1%) abortaram e 1 (0,4%) apresentou falsa gestacao. As variaveis explicativas que melhor discriminaram as femeas quanto ao numero total de leitoes nascidos (variavel objetiva) foram: antecedentes reprodutivos, infeccao urinaria, temperatura retal no dia da cobricao e ate quatro dias apos, tempo de cobricao, metodo de cobricao e soroconversao para parvovirus. Os resultados sugerem que e possivel melhorar o desempenho reprodutivo dos rebanhos suinos pela identificacao e correcao dos fatores de risco identificados neste estudo.

O uso de ducha: efeito sobre o bem-estar e a qualidade da carcaça e da carne em suínos transportados para o abate

This study was carried out to evaluate the effects of a shower before and after pig transportation on welfare, meat and carcass quality. We used 384 crossbreeding animals (females and castrated males), from 16 farms in Santa Catarina State, Brazil. A 2x4 factorial arrangement of treatments was employed with two distances from farm to slaughter plant (less than 50km and more than 50km) and four showering protocols. These protocols were applied on pigs: no showering at farm or slaughter plant (Control), no showering at farm but showering at the plant (NMG_MOF); showering at the farm and no showering at the plant (MOG_NMF); showering at the farm and plant (MOG_MOF). None of the factors influenced (P>0.05) physiological variables related to stress (cortisol and lactate in blood samples), number of carcass lesions and the characteristics of meat quality.