N. Mores

Fatores associados à soroprevalência de Salmonella em rebanhos comerciais de suínos

A cross-sectional study was conducted with 65 finishing pig herds from the states of Rio Grande do Sul and Santa Catarina, Brazil, in order to identify factors associated with seroprevalence for Salmonella. Pig farms were visited one week prior to slaughtering of animals when personnel were asked to answer a questionnaire. Feed was also sampled for attempts of Salmonella isolation, water for colimetrics analisis and around 40 pigs were bled. Feed samples were subjected to Salmonella isolation in selective media and sera were tested in an ELISA, plates were coated with antigens of serovar Typhimurium. Herds were classified in one of three categories according to the prevalence of ELISA positive sera, being low (less then 40% of positive sera), medium (between 40 and 70% positive sera) or high (more then 70% positive sera). Seroprevalence was used as the explanatory variable and results obtained from the attempts to isolate Salmonella from feed, water colimetrics results and the questionnaire answers were used as explanatory variables. Initially, attempts of association between explanatory and explained variables were performed using the chi-square test. When associated (P£0.1), the two variables underwent multiple correspondence analysis. Factors associated with herds having high seroprevalence were: in finishing herds, pelleted feed, swine manure disposal less than 100m from surface water, feeder not provided with water drinker, swine from several herds transported together to slaughterhouse; in the farrow-to-finish herds, feed ingridients exposure to other animals, no active rodent control, dry feed, absence of fence, whitewashing of facilities after cleaning and disinfecting and permission for other people entrance to the herd. Among the 65 pig herds visited, 98.5% were ELISA-positive, with seroprevalence of 57.6% (confidence interval 56 to 60%).

Effect of organic acids and mannanoligosaccharide on excretion of Salmonella typhimurium in experimentally infected growing pigs

The effect of organic acids and mannanoligosaccharide addition to the diet was assessed in pigs orally inoculated with Salmonella typhimurium. Forty-six growers were distributed among four treatments: Basal Diet (BD); BD+encapsulated organic acids; BD+free organic acids; BD+mannanoligosaccharide. Seroconversion was monitored, and feces and tissue samples were tested for Salmonella isolation. No treatment prevented the carrier state, but a tendency of lower fecal excretion was observed in the group treated with mannanoligosaccharide.

Erradicação da doença de Aujeszky em Santa Catarina: importância da condição sanitária das leitoas de reposição

A doenca de Aujeszky (DA) e uma infeccao causada por um herpesvirus, o virus da DA (VDA), primariamente em suinos. Esta doenca esta presente no Estado de Santa Catarina (SC) desde 1984. Devido ao impacto da DA no mercado exportador de carne suina, no comercio de reprodutores e nas perdas de produtividade, um programa de erradicacao, financiado por uma parceria entre a industria e a associacao de produtores tem tido sucesso em eliminar gradualmente a DA de rebanhos suinos de SC. O ultimo caso de DA no estado foi identificado em julho de 2004. Durante o processo de despovoamento/repovoamento, foi detectado um rebanho suino positivo para o VDA localizado no oeste de SC. Estudos de rastreabilidade da origem daqueles animais indicaram que a fonte era uma granja que distribuia reprodutores ilegalmente sem certificacao sanitaria. Este suinocultor mantinha um sistema de integracao que incluia 40 diferentes produtores para quem eram comercializados reprodutores e/ou suinos para terminacao. Testes de soroprevalencia detectaram anticorpos anti-VDA em 12 daqueles rebanhos. Devido a sua localizacao dentro do raio de 2,5km do foco inicial, uma outra granja, onde havia uma central de inseminacao artificial que distribuia semen suino para outras 5 granjas do mesmo proprietario, foi testada e tambem resultou positiva. Os objetivos deste artigo sao descrever as condicoes sanitarias frente ao VDA naquelas granjas que receberam suinos ou semen suino daqueles suinocultores, as medidas para controlar e eliminar o VDA dos rebanhos positivos e a situacao atual decorrente deste trabalho. Alem disso, o artigo busca alertar que medidas de vigilância ativa e normas sanitarias para comercio e distribuicao de material genetico devem ser seguidas, caso contrario, a DA pode recrudescer e tornar-se fora de controle como ocorria antes do inicio deste programa.

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 relacionados com o desempenho de leitões lactentes em granjas de suínos da região norte do Paraná

Eighteen farms of swine from North of Parana State, Brazil, were evaluated during the year of 1994. In the herd, at least six sows and her litters were evaluated from the birth up to weaning by four objetive variables (diarrhoea in the suckling, mortality rate, weight variation coefficient at weaning and average daily weight gain in the period), and were observed sixteen explainatory variables: (daily thermal amplitude, % area of the windows in the pant, pen s area, corporal status of the sow, creep presence, farrowing assistance, weight at birth, onfalite presence, internal minimal temperature in the plant, litter size at birth, colibacilosis vaccination, sows per plant, coletive suckling, roof presence in the plant, intestinal parasites presence and sanitary breack utilization. The variables were evaluated by the ECOSUI program developed by EMBRAPA/CNPSA. The main risk factors observed were: high internal minimal temperature, high thermal amplitude, sanitary break absence, roof absence, high sows per plant, insufficient pens area, onfalite and intestinal parasites presence and colibacilosis vaccination absence (founded in 50% of farms). The rates of the objetive variables were insatisfatory. The relation of diarrhoea presence was 8/18; to mortality rate the relation was 5/17; to weight variation coefficient, 0/18; and to the average daily weight gain, 9/17. The results indicate that the preventive veterinary medicine is very importam to reduce these risk factors to improve the suckling pigs performance.

Estudo ecopatológico da diarreia pós-desmame em granjas suinícolas do sudoeste do Paraná

The main risk factors that interfered on the performance of post weaning piglets were identified in nine farms from Southwest of Parana State, Brazil, during the Summer and Winter of 1991. All the herd were evaluated, with at least 30 piglets per farm, from weaning up to 21 days after weaning. The software ECOPOR was used to evaluate three target variables (mortality, diarrhea and average daily gain), and seven explanatory variables (average weaning weight, weight variation coefficient, thermal amplitude, sow energy consumption, water potability, diahrrea in the suckling period and housing density). The risk factors with higher frequency were daily thermal amplitude higher than 6°C, bacterial contamination of the drinking water, and the occurrence of diarrhea in the suckling period. Im more than 50% of the farms, low mean gain and differences in litter size were observed. Based on the analyses of the risk factors, a map classifying regions with different risk of post weaning diarrhea was constructed and the farms were allocated.

Efeito de probiótico na infecção e excreção fecal de Salmonella em suínos

Control of Salmonella transmission has been a challenge for the pork production companies. The aim of this study was to evaluate the effect of oral administration of probiotics on the occurrence of infection and fecal excretion of Salmonella in growers. The treatments consisted of basal diet without additives (control) or added of probiotic (107cfu g-1 of viable cells of the genera Bifidobacterium, Enterococcus, Lactobacillus and Saccharomyces). Six 50 days-old pigs were allocated into each treatment, with two replicates per treatment. All animals were inoculated with Salmonella Typhimurium (106cfu mL-1) after 14 days of housing. Afterwards, blood and feces samples were taken weekly and on day 35 post-inoculation the animals were euthanized and necropsied. The animals in both treatment groups were infected by Salmonella and seroconverted. There was no difference (P>0.05) between groups in mean counts of Salmonella, Enterococcus, Lactobacillus and coliforms in the feces samples, but the probiotic administration resulted in a lower frequency of isolation of Salmonella from liver (P=0.04), mesenteric lymph nodes (P=0.04), lung (P=0.03) and spleen (P=0.01). It was concluded that the probiotic microorganisms tested in this study were not able to protect against the infection or to decrease the fecal excretion of Salmonella in growing pigs, but were able to decrease the number of carriers in the mesenteric lymph nodes.

Substituição parcial do farelo de soja por soja integral extrusada na dieta de leitões desmamados

A study including two experiments was carried out to evaluate partial substitution of soybean meal (SM) by full-fat extruded soybean (ES) in the pre-starter diet, for piglets weaned at 21 days of age. In each experiment four levels (0, 20, 40 and 60%) of substitution of SM by ES were compared. In the first experiment, daily feed intake (DFI) and feed:gain ratio linearly increased for the total nursery period, due to substitution of SM by ES. Daily gain (DG) was not affected. Average height of the intestinal mucousa (HIM) in the low jejunum was linearly reduced, and in the duodenum had a quadratic effect, when ES was increased. In the experiment 2, DG, DFI and body weight at the end of the nursery phase (BW35) had a quadratic response, in consequence of substitution of SM by ES. It was concluded that partial substitution of SM by ES in the pre-starter diet for piglets weaned at 21 days of age provide an improvement for performance of piglets in the initial period after weaning. In the experiment 1, it was not possible to determine the maximum value for substitution of SM by ES, because DG showed a linear response until 60% of substitution. However, in the experiment 2, the best result for DG, estimated through the derivatization of the quadratic equation, was obtained at 26.82% of substitution, from 0 to 14 days post weaning.

Ecopatologia da diarréia pós-desmame em granjas de suínos da região norte do Paraná, Brasil

Eighteen farms of swine, located on North Parana State, Brazil, were evaluated during the year of 1994. In the herd, at least 30 piglets per farm were evaluated from weaning up to 21 days after weaning. Three objective variables (mortality rate, diarrhoea ocurrence and daily weight gain) and nine explanatory variables (daily weight gain 21days after weaning, sow energy consumption, housing density, piglets/pen, % sneezing, % sniffling, feed consumption/day/lactant sow, lenght of feeder/piglet and sanitary break utilization) were evaluated. The variables were evaluated by a program developed by EMBRAPA/CNPSA. The risk factor with higher frequency was absence sanitary break (observed in 83.34% of the farms). Others factors (observed in 40-70%) were: high housing density, low sow energy consumption, low daily weight gain 21 days after weaning and high number of piglets per pen. The others variables were present at low level. The ocurrence of diarrhoea was founded in 50% of farms. The mortality rate was 2.97%, and the daily weight gain was 249 g/day. By the factors that were analysed, the farms were inserted in a map, indicating their location in the risk regions for diarrhoea incidence.