Occurrence of gastrointestinal parasitic diseases of swine in different production phases in commercial pig farms from the State of Santa Catarina, southern Brazil / [Ocorrência de parasitoses gastrointestinais dos suínos, nas diferentes fases de produção, em granjas comerciais de Santa Catarina, Brasil]

Gastrointestinal parasites are important, since they can cause a decrese in the performance of swine. The occurrence of parasites in pig farms can create economic losses such as reduction in the value of carcasses and increasing expenses with medicines and veterinary assistance. This study aimed at investigating the occurrence of intestinal parasites in different phases of production reared pigs in intensive prodution systems in the western region of the State of Santa Catarina. A total of 403 fecal samples were analyzed, of which 51.86% were positive for one or more parasites in different phases of production. Finishing pigs had the highest prevalence of parasites (60.19%) followed by nursery pigs (55.44%), pigs in breading sows (50.49%), and suckling piglets (40.81%). Strongylida parasites had higher occurrence (28.78%), and were also the most frequent in the finishing, breading sows, and nursery phases. Coccidia were more occurrent in suckling piglets. This study highlights the need of implementing suitable antiparasitic control measures in all phases of swine production associated with a surveillance system for the diagnosis of endoparasite infection in pigs. Our results demonstrate that endoparasites are highly occurring in pigs, even in intensive system animals on technified farms.(AU)

Parasitas gastrointestinais são importantes, pois podem causar uma diminuição no desempenho dos suínos. A ocorrência de parasitas em granjas de suínos pode gerar perdas econômicas, como redução no valor das carcaças e aumento de gastos com medicamentos e assistência veterinária. Este estudo teve como objetivo investigar a ocorrência de parasitas intestinais nas diferentes fases de produção de suínos criados em sistemas intensivos, na região oeste do estado de Santa Catarina. Foram analisadas 403 amostras fecais, das quais 51,86% foram positivas para um ou mais parasitas nas diferentes fases de produção. Os suínos de terminação apresentaram a maior prevalência de parasitas (60,19%), seguidos por suínos de creche (55,44%), suínos em gestação (50,49%) e leitões em lactação (40,81%). Parasitas da ordem Strongylida tiveram maior ocorrência (28,78%) e também foram os mais frequentes nos estágios de terminação, reprodução e creche. Coccídios foram mais ocorrentes em leitões lactentes. Este estudo destaca a necessidade de implementar medidas de controle antiparasitário adequadas em todas as fases da produção suína, associadas a um sistema de vigilância para o diagnóstico de infecção por endoparasitas em suínos. Os resultados demonstram que os endoparasitas são altamente ocorrentes em suínos, mesmo em animais de criação intensiva em granjas tecnificadas.(AU)

Inhaled nitric oxide selectively reduces pulmonary hypertension after ovine smoke inhalation but does not improve oxygenation.

Inhaled nitric oxide (NO) is known to selectively reduce pulmonary hypertension and improve the ventilation-perfusion relationship in subjects with lung injury of various origin. However, some forms of lung injury do not react to inhaled NO at all, or show only a reduction in pulmonary arterial pressure. Very little is known about the effects of inhaled NO after smoke inhalation injury. We investigated the effects of inhaled NO in an established model of ovine smoke inhalation injury. Chronically instrumented sheep (n = 8) had tracheostomies and were insufflated with smoke generated from burning cotton cloth (4 times at 12 breaths each). They were then connected to a ventilator with oxygen-enriched air to achieve arterial oxygen tensions within the normal range. After 48 hours, NO was added to the inspired gas in ascending concentrations of up to 100 ppm. Systemic and pulmonary hemodynamics as well as oxygen transport were analyzed. Inhaled NO dose dependently lowered the pulmonary hypertension. Concentrations higher than 20 ppm did not further reduce the pulmonary artery pressure. Right ventricular stroke work index was significantly improved owing to the reduction in pulmonary vascular resistance. Arterial oxygenation, however, was not optimized by inhaled NO, probably because of interstitial edema formation.

Burn-associated bone disease in sheep: roles of immobilization and endogenous corticosteroids.

To determine the role of immobilization in the pathogenesis of burn-associated bone disease, we selected the sheep as a model to study the effects of burn injury compared with a sham-burned control group. Seven of the sheep were subjected to controlled 40% flame burn, and seven underwent anesthesia with arterial and venous cannulation but without burn. After labeling newly formed bone with tetracycline and calcein, the sheep were killed 2 weeks after burn or sham burn, and the iliac crest and lumbar vertebrae were analyzed for histomorphometry. Analysis failed to demonstrate a significant reduction of bone formation rate in the burned sheep. Osteoid area and surface and osteoblast surface, which correlated significantly with bone formation rate (r = 0.49, p < 0.025), were reduced in the burned sheep. Results suggest that immobilization may play a primary role in the pathogenesis of burn-associated bone disease, but the presence of differences in other histomorphometric features indicates the bone disease is multifactorial.

Effects of manganese superoxide dismutase on lung fluid balance after smoke inhalation.

There is evidence of increased oxygen free radical activity after smoke inhalation with and without concomitant burn injury. We determined the effects of manganese superoxide dismutase (Mn SOD) on lung fluid balance as measured by lung microvascular permeability coefficient (sigma), filtration coefficient (Kf), and lymph flow. Merino breed ewes (n = 6/group) were surgically prepared. The SOD group (SOD) received Mn SOD (9,000 U/kg) as an intravenous bolus and was insufflated with smoke. The control group (CON) received saline and smoke. sigma and Kf were determined 24 h before and 24 h after smoke injury. Lymph flow, arterial O2-to-inspired O2 fraction ratio, systemic hemodynamics, and pulmonary arterial and capillary pressures were measured. The sigma was significantly (P < 0.05) higher after smoke insufflation in SOD compared with CON (0.71 +/- 0.03 vs. 0.53 +/- 0.05). Kf was significantly lower after smoke insufflation in SOD compared with CON (0.038 +/- 0.010 vs. 0.061 +/- 0.010). Lymph flows were significantly lower during the 24 h after smoke insufflation in SOD compared with CON (33 +/- 7 vs. 55 +/- 8 ml/h at 24 h). Arterial O2-to-inspired O2 fraction ratio was significantly improved at 6 and 12 h after smoke insufflation in SOD compared with CON at the same time points. Mn SOD meliorates the lung microvascular permeability changes associated with smoke inhalation injury.

Elimination of PBBs in rats. Effect of mineral oil and/or feed restriction.

Rats were fed polybrominated biphenyls (PBBs) at 0.1 to 100.0 ppm for 14 d and then treated to hasten the removal of PBBs with 0, 5, or 10% mineral oil (MO) and/or 0, 15, 30, or 45% feed restriction (FR) for 21 d. PBB body burdens were determined at d 14 and expressed on a log-log basis by Y = 0.91X + 2.179 (r2 = 0.974), where X = log of PBB concentration in diet (ppm) and Y = log of PBB body burden (micrograms). After 21 d withdrawal, body burdens were expressed by the equation Y = 0.787X + 2.218 (r2 = 0.95). The most effective withdrawal treatment was 10% MO + 45% FR producing a reduction of body burdens inversely related to prior body burdens (69% at 0.1 ppm to 23% at 100 ppm). Body weights and fat content were significantly (p less than or equal to .05) reduced by feed restriction, with fat content only 39% of controls at 21 d off. Mortality averaged 0, 13.6, and 35.8% for rats fed 0, 5, or 10% MO, and 25, 15, 8.6, and 3.7% for rats feed restricted at 0, 15, 30, and 45%, respectively. Histopathology of the dead and moribund rats indicated that the clinical signs were not characteristic of PBB toxicity. In a second experiment, safflower oil at 3.5% or excess vitamins prevented the mortality and clinical signs associated with MO during withdrawal from 100 ppm PBBs. Based on these data and those in the literature, PBBs interfere with vitamin utilization.

An ecotoxicological study of a population of the white footed mouse (Peromyscus leucopus) inhabiting a polychlorinated biphenyls-contaminated area.

White footed mice (Peromyscus leucopus) inhabiting an area surrounding a pond (Tyler) contaminated with polychlorinated biphenyls (PCBs) and metals (Cadmium, Zinc, Copper) had whole body burdens of 0.42-4.17 ppm PCBs (mean 2.3 ppm) and animals from a comparison nonpolluted site (WCC) had no detectable PCBs. Males and females caught at the polluted site in the winter months were not significantly different in body weight or length when compared to WCC animals, but Tyler animals had significantly increased relative liver, kidney, spleen and adrenal weights. In the summer months, mostly males were caught at both Tyler and WCC sites. Tyler males were significantly lighter than WCC males, and had a significantly increased relative liver weight when compared to the males from the WCC site. In addition, the adult Tyler males had significantly lower relative testis weights. At Tyler there was a significantly smaller proportion of juveniles and subadults in the population than at WCC. Polychlorinated biphenyls levels in the adult Tyler males were significantly positively correlated with relative liver weight, but there were no significant correlations with any of the other structures measured. These results suggest that at the polluted site there is inhibition of reproduction and changes in liver, spleen, adrenal, and testis function.