A.L. Amaral

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.

Concentração de macronutrientes e metais pesados em maravalha de unidade de suínos em cama sobreposta

The swine production industry in Brazil has been severely criticized due to pollution, mainly in water, that has been noticed in regions where swine production is concentrated. This fact puts in question the current production model. Deep bedding system for swine production appears as a promising alternative, because it reduces the risks of contamination by converting manure management from liquid to solid phase. Additionally, it makes possible the production of organic compost, which can generate extra income or can be applied in the same farm to implement an organic agricultural production. This study evaluated the increase of macronutrients, copper and zinc concentrations in wood shavings used as a substrate in four stalls during a period when 8 groups of 70 animals were raised. Each stall had animals installed during 35 days, according to their age of entrance (nursery = 21, S1 = 56, S2 = 91 and S3 = 126 days). Results have shown that average concentrations of nutrients in beds are in compliance with legislation for simple organic fertilizer. The concentration of zinc in the nursery bed was about 5 times higher than other stalls, which shows the influence of diet on the composition of the compost.

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.

Disseminação do vírus da doença de Aujeszky, envolvendo o comércio de reprodutores suínos de reposição

ABSTRACT It was reported the spreading of the infection caused by the virus of Aujesky’s disease (VAD) by the commercialization of breeders originated from two pigs farms GRSC (Farms of Certified Swine Breeders - FCSB) which had an outbreak of Aujeszky’s disease. After the positive diagnosis of Aujesky’s disease, the pigs traded from 37 to 45 day before the outbreaks were removed from the herd, bled for serological exams for the VAD and sent to slaughterhouses. The herds which received these pigs were serologically tested for the VAD, 17 to 37 days after the removal of the animals. Serological tests were also performed in pigs lodged at neighboring cages to those which had been lodged with the pigs bought and a sampling test was done six months later. Thus, 52 flocks bought pigs from the farms 1 and 2. From those, 37 (69.8%) received at least one serum-positive pig for the VAD. Only seven (18.9%) of them were infected and 30 (81.1%) pigs showed no indications of infection by the VAD. The occurrence of VAD in FCSB farms represents huge potential for spreading of the VAD, by the trade of replacement pigs. The traceability investigation and removal of the animals traded before the diagnosis, with immediate removal of the positive lots of pigs at the destiny herd, avoided the spread of the infection. Keywords: swine, disease, virus, Aujeszky, epidemiology

Fatores de risco associados à ocorrência de linfadenite em suínos na fase de crescimento-terminação

An epidemiological study in 60 units of swine termination (UT), pertaining to producers integrated with the main Agribusiness of the States of Santa Catarina and Rio Grande do Sul. These units had been selected due to the occurrence of lymphadenitis in slaughtered pigs. The batch size studied in each UT varied from 22 to 960 pigs. The animals were considered positive or negative for lymphadenitis, following the evaluation routine of the Service of Federal Inspection (SIF) at slaughter. For data collection at the UTs, a questionnaire with 156 variables was applied at a single visit to the farms. In the 60 UT studied, the percentage of positive animals for lymphadenitis was 10.37%. Among the variables analyzed, nine risk factors were identified (explicative variables) and associated with the occurrence of lymphadenitis (objective variables). The explicative variables were: bad hygiene of the feeders and drinking fountains, untreated drinking water, bad conservation of the facilities, use of the same truck for ration and animal transportation, production of ration inside the farm, free access of other animals to the ingredients of ration, storage of ready usable ration in boxes or bags and handling of the production of animals in an continuous system.

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.

Uso do plasma suíno ultrafiltrado na recuperação de leitões com sinais clínicos de circovirose

The effect of the ultra-filtered spray-dried porcine plasma, associated to a commercial acid in the drinking water was tested for recovering pigs with clinical signs of the porcine postweaning multisystemic wasting syndrome (PMWS). Forty piglets with clinical signs of the PMWS were used following a selection at 20 days after their housing in one finishing facility. They were divided in four treatment groups (T) of 10 pigs each: T1 - chlorine treated water ad libitum (control); T2 - solution prepared with 2.5% of plasma diluted in water; T3 - acid (Selko® ) diluted in water at the concentration of 12 ml/10l; T4 - solution prepared with 2.5% of plasma diluted and the acid (Selko® ) diluted in water at the concentration of 12 ml/10l. The pigs received no medication and were euthanized at 28 or 40 days after the beginning of the experiment for serological and pathological tests. Differences at the weight gain and in the clinical-pathological situation were not observed among the treatments. However, pigs from T4 were in better clinical-pathological situation. The pigs of all four treatments showed a good recovery, although they were not medicated. Even though, it was observed a high frequency of lesions compatible to PMWS in the lungs, kidneys and lymph nodes. It was concluded that the plasma spray-dried associated to the acid did not improve the performance and the clinical-pathological situation of pigs with clinical signs of PMWS.The effect of the ultra-filtered spray-dried porcine plasma, associated to a commercial acid in the drinking water was tested for recovering pigs with clinical signs of the porcine postweaning multisystemic wasting syndrome (PMWS). Forty piglets with clinical signs of the PMWS were used following a selection at 20 days after their housing in one finishing facility. They were divided in four treatment groups (T) of 10 pigs each: T1 - chlorine treated water ad libitum (control); T2 - solution prepared with 2.5% of plasma diluted in water; T3 - acid (Selko® ) diluted in water at the concentration of 12 ml/10l; T4 - solution prepared with 2.5% of plasma diluted and the acid (Selko® ) diluted in water at the concentration of 12 ml/10l. The pigs received no medication and were euthanized at 28 or 40 days after the beginning of the experiment for serological and pathological tests. Differences at the weight gain and in the clinical-pathological situation were not observed among the treatments. However, pigs from T4 were in better clinical-pathological situation. The pigs of all four treatments showed a good recovery, although they were not medicated. Even though, it was observed a high frequency of lesions compatible to PMWS in the lungs, kidneys and lymph nodes. It was concluded that the plasma spray-dried associated to the acid did not improve the performance and the clinical-pathological situation of pigs with clinical signs of PMWS.

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.

Avaliação histopatológica de órgãos reprodutivos e bexiga de fêmeas suínas descartadas

Reproductive failures are the major reasons for removal of sows and decrease of production rates in an intensive swine production system. Urinary infection and endometritis are considered important causes for culling of sows, due to relevant reproductive consequences and increase of the replacement rates. The present study aimed to evaluate the reproductive and urinary system of culled sows, as well as investigate the occurrence of cystitis and endometritis in analyzed sows. Samples, such as ovaries, uterus fragments and bladder were collected from 79 sows originated from 20 farms of Santa Catarina State. Results showed that, 32 (40,5%) analyzed sows presented cystitis in different levels, 24 (30,4%) had some class of uterine inflammation, and 9 (11,4%) were in anestrous, with inactive ovaries. However, unsignificative dependence between cystitis and endometritis in analyzed samples was observed.