Risk factors associated with toxoplasmosis and toxocariasis in populations of children from nine cities in southern Brazil.

This study investigated the epidemiological factors that contribute to the seroprevalence of Toxoplasma gondii and Toxocara spp. in children from Paraná state, Brazil. Immunoglobulin G (IgG) antibodies to T. gondii were detected using indirect immunofluorescence, and IgG antibodies to Toxocara were detected using an enzyme-linked immunosorbent assay. For each individual, a questionnaire was completed that contained epidemiological and clinical data. The data analysis was performed using multiple logistic regression. Of the 544 children investigated, 3.2% presented co-infection with T. gondii and Toxocara spp. Of this total, 7.4% were positive for antibodies to T. gondii, and 25% were positive for antibodies to Toxocara spp. The presence of antibodies to Toxocara spp. increased the risk of T. gondii infection (P = 0.029). Children who were 1-8 years of age were less infected by T. gondii than those who were 9-12 years of age. The variables that influenced positivity for anti-Toxocara spp. were the origin of the children and contact with sand. Children with positive serology for Toxocara spp. presented more eosinophilia compared with those with non-reactive serology. Infection with both parasites reveals the need for preventive measures, such as guidance about modes of infection, parasite control and monitoring recreational areas.

Effects of aflatoxins on performance and exocrine pancreas of broiler chickens.

The aim of this research was to evaluate, on a weekly basis, the effects of aflatoxins on the activity of digestive enzymes (alpha-amylase, lipase, and trypsin) in the pancreas as well as on the performance and histology of pancreas in broiler chickens over the course of 42 days. One thousand and eighty 1-day-old male Cobb broilers were divided into four treatments with 18 replicates and 15 birds per replicate (i.e., 270 broilers per treatment). Treatments were established according to the amount of aflatoxins added to the diet, as follows: T1 = 0 mg of aflatoxins per kilogram of feed (mg/kg); T2 = 0.7 mg/kg; T3 = 1.7 mg/kg; and T4 = 2.8 mg/kg. Pancreas sample collection was performed from one bird out of each replicate at 7, 14, 21, 28, 35, and 42 days of experiment, which yielded a total of 18 samples per treatment on each collection. Each sample was homogenized in distilled water, frozen in liquid nitrogen, lyophilized, and stored at -20 C until analysis. Performance parameters (body weight, feed consumption, and feed conversion rate) were measured at 21, 35, and 42 days of experiment. At the end of the experiment (42 days), six birds from each treatment were randomly chosen for histologic evaluation of the pancreas. The presence of aflatoxins in the diet induced a negative effect on all performance parameters. The pancreatic activity of lipase and alpha-amylase were significantly increased in treatments T3 and T4, while the specific activity of trypsin was only affected during treatment T4. In addition, several histologic changes were observed in the pancreas of birds receiving aflatoxin-contaminated feed. Aflatoxins present in the feed determined an increase in the activity of pancreatic enzymes in broilers, affecting the digestibility of the diet, thereby leading to losses in performance and productivity.

Individual and combined effects of Salmonella typhimurium lipopolysaccharide and fumonisin B1 in broiler chickens.

The aim of this research was to evaluate the individual and combined effects of Salmonella typhimurium lipopolysaccharide (sLPS) and fumonisin B(1) (FB) on performance, relative weight of liver, biological parameters, and histological evaluation of several tissues from four hundred thirty-two 1-d-old male broiler chickens divided into 9 treatments according to the dose of FB (0, 100, or 200 mg/kg, from d 1 to d 28) and sLPS (0, 250, or 500 µg/application per bird, every other day, from d 15 to 27) administered. At the end of the experiment (28 d), significant effects caused by sLPS, FB, and the interaction of sLPS × FB were observed on several parameters. Histopathological evaluations showed significant lesions in liver and kidney caused by sLPS, FB, and their association. According to these results, both sLPS and FB (isolated or in association) cause significant effects on performance and biological parameters of broilers at 28 d of age.

Seroprevalence of Toxocara infection in children and environmental contamination of urban areas in Paraná State, Brazil.

The objectives of this study were to evaluate the contamination by eggs of Toxocara in sandy areas or grass lawns of outdoor recreation areas that are used by children, and the frequency of seroprevalence in children, from three cities of fewer than 45,000 inhabitants in Paraná, Brazil. From May 2005 to December 2007, five samples were taken from each of 13 sandy sites and 18 grass lawns, all from plazas and public schools. Blood samples from children aged 0-12 years were analysed by immunoassay for anti-Toxocara IgG. The soil samples were processed by floatation and sedimentation. Eggs of Toxocara spp. were present in 44.7% (38/85) of the samples from grassed areas and in 21.4% (15/70) of the sand samples. The lawns were 2.16 times more contaminated than the sand (P = 0.0009). However, the epidemiological variables showed no statistically significant difference between seropositive (36.8%; 130/353), and seronegative children. The rate of seropositivity was higher in children aged 0-5 years (P = 0.03), who were 1.94 times more likely to develop persistent wheezing (P = 0.02).