W. Barioni Junior

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.

Comparação entre métodos de tuberculinização no diagnóstico da infecção por agentes do complexo Mycobacterium avium ou M. bovis em suínos

The efficiency of the tuberculin delayed-type skin hypersensitivity test was evaluated in swine. A comparison of the tuberculin skin tests was performed with avian and bovine protein derivatives (PPD), in the detection of Mycobacterium avium-Complex or M. bovis infected swine. The methods were evaluated as to define criteria for readings and results interpretation, to determine their capacity in detecting Mycobacterium avium complex (MAC) infected swine and their performance in differentiating MAC from M. bovis-infected individuals. Three trials were performed with naturally MAC-infected swine, experimentally MAC-infected or experimentally M. bovis-infected animals. The skin test readings positive or negative were, respectively, correlated to the presence or absence of gross lesions and histological alterations in lymph nodes at slaughter age. Reaction with both antigens were observed in MAC and M. bovis-inoculated animals as well. Reactions wider then 0.5cm in diameter or showing skin thickness increasing more then 0.2cm in the time frame between inoculation and reading were considered to be positive, as compared to the average results of the group. Herds with MAC-infected swine could be detected with either avian or bovine PPD. Both diameter and skin thickness were efficient in detecting MAC-infected swine, however, reading the diameter of the reaction was shown to be more easily and economically performed.

Fatores de risco associados com artrites em suínos de abate

An epidemiological observational study was carried out in 63 swine finisher units aiming to identify the risk factors associated to the occurrence of arthritis at slaughter. In each farm, about 220 animals were evaluated for 110 days, and 42 variables, one objective (swine condemned for arthritis) and 41 explicative, were collected from the arrival of the pigs to the farm until submitted to the Federal Inspection at slaughter. Data were analyzed by descriptive statistics and multivariate methods. Out of the 63 studied farms, 27.0%, 33.3% and 39.7% had high (>0.7%, low £ 0.7%) and no occurrence (0.0%) of animals condemned for arthritis. There was an association between the occurrence of arthritis and low daily weight gain, low carcass meat yield, poor feed conversion rate and low carcass weight. The risk factors associated with arthritis at slaughter were: farms with historical data of condemnation for arthritis, more than five years without carrying out floor repairs, male sex, absence of ceiling lining in the facilities, pen cleaning only once a day, bad conditions of swine transport to the slaughterhouse, finisher units with more than 250 housed animals and more than 10 different pigs suppliers in the lot formation.

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.

Fatores de risco associados ao vício de sucção em leitões na fase de creche

Risk factors associated with the suckling vice in post-weaning piglets were studied in an epidemiological survey in 65 swine herds in South Brazil. This follow-up study was performed in one group of piglets from each herd from birth to 21 days post weaning. Every group was composed by piglets from at least six litters. Data related to housing, feeding, breeding practices, internal environment in the weaning facilities and individual piglets performance were collected for descriptive and multiple correspondence analyses. Suckling vice was identified in 23 (35.4%) herds and groups presenting suckling vice had lower growth rates (P<0.005). Main risk factors associated with suckling vice were weaning weight lower than 6.3kg, unavailability of drinkers for piglets in the farrowing house, occurrence of post-weaning diarrhea, post-weaning drinkers of a different model than the ones available during the suckling term, inadequate axis direction of the building, presence of signs of mange, no all-in-all-out procedure in the post-weaning facilities, and the use of feed restriction immediately after weaning. The authors suggest that a correction of these factors would reduce the occurrence of suckling vice in post-weaning piglets and improve their grow rates after weaning.