Giardia duodenalis: kinetics of cyst elimination and the systemic humoral and intestinal secretory immune responses in gerbils (Meriones unguiculatus) experimentally infected.

This study aimed to determine the pre-patent period and to evaluate the kinetics of cyst elimination and the systemic humoral (IgA, IgG(1), IgG(2a), IgM, IgE) and intestinal secretory (IgA) immune responses in gerbils (Meriones unguiculatus) experimentally innoculated with different doses of Giardia duodenalis trophozoites. Forty-eight animals aged 6-8 weeks were used, equally distributed among six groups, five groups innoculated with different doses of trophozoites (10(1), 10(2), 10(3), 10(4), 10(5)) and one control (non-infected) group. Coproparasitological examinations were carried out daily up to 91 days after inoculation (d.a.i.) to determine the pre-patent period and the kinetics of cyst elimination. Blood and stool samples were weekly collected for antibody assays. The pre-patent period was observed from the 9 d.a.i. onwards, with intermittent elimination of variable quantities of cysts up to 27 d.a.i.. All infected gerbils, irrespective of the dose received, were able to mount systemic humoral immune responses as evidenced by specific IgM titers from 7 to 28 d.a.i., corresponding to the peak of cyst elimination, followed by high and persistent IgG1 titers. Intestinal secretory responses were also seen with two peaks of fecal IgA titers, corresponding to IgM and IgG1 response peaks, respectively. In conclusion, systemic and intestinal humoral immune responses were related to the control of giardiasis in this experimental model.

An alternative method for DNA extraction and PCR identification of Entamoeba histolytica and E. dispar in fecal samples.

Since it is known that Entamoeba dispar is non-pathogenic and morphologically similar to E. histolytica, there are many targets used in PCR for differentiating these species. However, obtaining high quality DNA from fecal samples is fundamental for PCR. Most methods are laborious or use kits that make diagnosis expensive. In the present work, a new simple, fast and cheap technique of DNA extraction from fecal samples was combined with a PCR for an episomal target in order to identify E. histolytica and E. dispar in feces.

Prevalence of Giardia duodenalis and Cryptosporidium spp. in dogs from different living conditions in Uberlândia, Brazil.

Infection rates with Giardia duodenalis and Cryptosporidium spp. were compared among dogs living under different conditions. Stool samples (n = 433) collected from dogs of different ages, gender, living conditions and origin were analyzed using three techniques, i.e., centrifugal flotation in zinc sulfate solution, centrifugal flotation in sucrose solution, and methylene blue gram safranin staining. Eighty-nine of the samples were from stay dogs living in shelters run by animal protection societies, 199 were from kennels and 122 from households. A total of 119 (29.0%) had G. duodenalis cysts and six (1.4%) were positive for Cryptosporidium spp. oocysts. Dogs from kennels were most frequently affected by G. duodenalis (49.7%) while those from shelters showed a higher prevalence of Cryptosporidium spp. (2.2%). A significant difference (p < or = 0.05) was observed between immature dogs and adults only with respect to Giardia infection. There was no significant difference between the gender with regard to the presence of either protozoan.

Infection of dogs by experimental inoculation with human isolates of Giardia duodenalis: clinical and laboratory manifestations.

The susceptibility of dogs to experimental inoculation with trophozoites and cysts of human isolates of Giardia duodenalis and the clinical and laboratory profiles of infection of these animals were studied. Two groups (A and B), each comprising three dogs, were inoculated with G. duodenalis trophozoites and cysts, respectively. A third group of two dogs was not inoculated and remained as control. After inoculation feces were collected daily to determine the pre-patent period, by flotation in 33% zinc sulfate solution. Blood samples (5mL) were collected from animals at 15-day intervals during the 165 days of the experimental period and were used to carry out the hemogram and biochemical evaluation of the levels of total protein, albumin, alanine aminotransferase, gamma glutamyltransferase, urea and creatinine. A prepatent period was observed at 5-6 days post-inoculation (p.i.) in the inoculated dogs, with cysts eliminated for approximately 3 months. No alterations were seen in the clinical parameters evaluated. Anemia was observed at 15 p.i. in the inoculated dogs. The mean eosinophil count of inoculated groups was higher than that of the control (p< or =0.05) but none of the biochemical parameters analyzed presented significant differences. The results of this study show that G. duodenalis from human isolates is able to infect dogs with minimal systemic manifestations without producing clinical signs of giardiasis.

Biochemical serum profiles in dogs experimentally infected with Angiostrongylus vasorum (Baillet, 1866).

The biochemical profiles of crossbred dogs experimentally infected with the parasite Angiostrongylus vasorum were studied. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L3) of A. vasorum per kilogram of body weight. A third group of five uninfected animals were used as control. Serum from these animals were used for biochemical tests to measure total and fractioned proteins, urea, creatinine and to determine the activities of aspartate (AST), alanine (ALT) aminotransferase, gamma-glutamyl transferase (GGT), alkaline phosphatase (PAL) and creatine kinase isoenzyme MB (CK-MB). The alpha-1, alpha-2 and beta-globulins fractions showed alterations during acute phase of the infection. No modifications were observed in the biochemical profiles of ALT, AST, GGT, PAL, urea and creatinine. CK-MB was shown to be a good early indicator of cardiac injury in dogs experimentally infected with A. vasorum.

Rupture of femoral artery in a dog infected with Angiostrongylus vasorum.

A crossbred bitch, infected with Angiostrongylus vasorum, died on the 46th day post infection. Post mortem findings showed that the rupture of the femoral artery was the cause of death. A. vasorum was present in the femoral artery.

Western blot analysis of the humoral response of dogs experimentally infected with Angiostrongylus vasorum (Baillet, 1866).

Seven cross-bred dogs were inoculated with Angiostrongylus vasorum and serum samples were analyzed using the enzyme-linked immunosorbent assay (ELISA) and Western blot (WB). ELISA detected specific antibodies anti-A. vasorum, from 14 to 28 days after inoculation (DAI) and persisted throughout the experiment. Using WB, the main antigens detected had molecular weight of approximately 115, 102, 86, 76, 69, 56, 41, 32, 28, 20-22 and 10kDa.

Prevalence of anti-Neospora caninum antibodies in dogs from urban, periurban and rural areas of the city of Uberlândia, Minas Gerais--Brazil.

In Brazil there are few reports on the prevalence of anti-Neospora caninum antibodies in dogs from urban, periurban and rural areas. Serum samples from 450 dogs, 300 from urban, 58 from periurban and 92 from rural areas, were tested for the detection of anti-N. caninum IgG antibodies using IFAT: indirect fluorescent antibody test (IFAT, > or =50). Antibodies were observed in 63 (14%) of the 450 serum samples analyzed, with 32 (10.7%) in dogs coming from the urban area, 11 (18.9%) from the periurban area and 20 (21.7%) from the rural area. Statistical differences were seen between the occurrences in animals from the urban area and those of the rural area (P = 0.01). The antibody titers found were: 1:50 in 20 dogs, 1:100-1:800 in 41 dogs, and 1:3200 in two dogs. In the female dogs, a smaller prevalence of dogs with antibodies was observed in those from the urban area (7.5%) in comparison with those of the rural (21.0%) (P = 0.05) and periurban (23.3%) (P = 0.01) areas. There were growing levels of antibody prevalence with the increase in age of the dogs in all three areas studied. Although this increase was not significant, it indicates a tendency towards more infections with age, suggesting post-natal exposure to N. caninum. However, a significant difference (P = 0.05) was observed in the occurrence of anti-N. caninum antibodies in dogs with ages = 2 years in urban (13.1% urban) versus rural environments (27.1% rural). Among the other age brackets studied the difference was not significant. The results confirm the presence of N. caninum in the region and reveal the important role of dogs in the parasite's epidemiology.

Prevalence and molecular characterization of Hepatozoon canis in dogs from urban and rural areas in Southeast Brazil.

The objective of this survey was to investigate the prevalence of Hepatozoon infection in dogs in the rural and urban areas of Uberlândia, Brazil by PCR and molecular characterization. DNA was obtained from blood samples collected from 346 local dogs from both genders and various ages. Seventeen PCR products from positive blood samples of urban dogs and 13 from the rural dogs were sequenced. Partial sequences of the 18S rRNA gene indicated that all 30 dogs were infected with Hepatozoon canis similar in sequence to H. canis from southern Europe. Four local dog sequences were submitted to GenBank (accessions JN835188; KF692038; KF692039; KF692040). This study indicates that H. canis is the cause of canine hepatozoonosis in Uberlândia and that infection is similarly widespread in rural and urban dogs.

Histomorphometry and macroscopic intestinal lesions in broilers infected with Eimeria acervulina.

This study aimed at measuring intestinal villi and assessing the intestinal absorptive area in broilers infected with Eimeria acervulina under different treatments to control coccidiosis. The experiment was divided into two stages, carried out in successive housings, raised in the same environment (or aviary). In the first stage, on 25 May 2008, fifty 12-day-old birds were orally inoculated with 3 x 10(3) oocysts of E. acervulina. In the second stage, on July 2008, other 50 birds were allocated on litter contaminated by the feces of birds on the first housing (natural infection by oocysts present in the reused litter). The experiment was arranged in a complete randomized design with five treatments and three replicates of 10 chicks per treatment. Broiler chicks were housed at 1 day of age and autopsies were performed at 21 days of age. Three 2-cm-long segments of the duodenum were excised from each bird and fixed in 10% buffered formalin. A total of 30 slides were prepared for each treatment, totaling 150 evaluated histological sections using H&E staining. Villus morphology was carried out by the HL Image 97 software. The intestinal absorptive area was calculated and macroscopic lesions were classified according to standard lesion scores. Results showed that intestinal villus measurements and absorptive area are directly affected by E. acervulina and that there is direct and positive correlation between the macro and microscopic findings observed in intestinal coccidiosis. E. acervulina causes shortening of villi and reduction in the intestinal absorptive area, affecting broiler growth. The prevention method of litter fermentation during the interval between housings and oral administration of Diclazuril can reduce the severity of intestinal lesions by E. acervulina in broilers impairing oocyst virulence or viability.

Anticoccidial efficacy of drinking water soluble diclazuril in the control of Eimeria acervulina oocysts on experimentally-infected broiler chickens / Eficiência do diclazuril (formulação líquida) no controle de oocistos de Eimeria acervulina em frangos de corte experimentalmente infectados

The experiment was carried out with 150 Cobb broiler chickens divided into 3 groups with 50 birds each. The groups of infected chickens orally received 1ml of inoculum containing 3x103 Eimeria acervulina sporulated oocysts at 12 days of age. Group 1 was kept as a positive control with infected non-medicated birds, group 2 was medicated with diclazuril (1%) with a dose of 1mL/4 L of drinking water for 2 successive days, 5 days after infection, while group 3 was kept as negative control with non-infected and non-medicated birds. Oocysts count per gram of feces, score of macroscopic intestinal lesions and weight gain were evaluated. The group treated with diclazuril showed significant and satisfactory improvement in the assessment criteria when compared to the infected non-medicated group. The results revealed more reduction in the total oocyst count and intestinal lesion score in the medicated than in the infected non-treated group. The results confirmed that (1%) liquid diclazuril is effective to control Eimeria infection.

O experimento foi realizado com 150 frangos de corte da linhagem Cobb, divididos em 3 grupos de 50 aves cada. Os frangos de dois grupos (G1 e G2) receberam, por via oral, 1mL de inóculo contendo 3x103 oocistos de Eimeria acervulina aos 12 dias de idade. O grupo 1 foi mantido como grupo controle positivo (infectado não medicado), o grupo 2 foi medicado com diclazuril (1%) na dose de 1mL/4 litros de água potável por dois dias sucessivos, cinco dias após a infecção. Um terceiro grupo (G3) foi mantido como controle negativo não infectado e não medicado. O número de oocistos por grama de fezes (OOPG), o escore de lesões macroscópicas intestinais e o ganho de peso corporal foram avaliados. No G1, o OOPG foi de 3,67x106 e o peso final foi de 1,392kg, valores significativamente diferentes do OOPG de 1,93x106 oocistos e do peso final de 1,613kg do G2 (diclazuril). Os resultados provaram que o diclazuril (1%) em formulação líquida e na dosagem de 1mL/4 litros de água por dois dias sucessivos foi eficaz no controle de Eimeria acervulina.

Concordância entre duas técnicas coproparasitológicas para diagnóstico de Fasciola hepatica em bovinos / Evaluation of two available methods to detect eggs of Fasciola hepatica in cattle faeces

Two different methods to detect Fasciola hepatica in faeces using kappa index were compared with four tamises technics and sequencial fitration in two tamises using Flukefinder® apparatus. High accordance between the two methods was observed. The values showed high sensibility and specificity.

Freqüência de helmintos em gatos de Uberlândia, Minas Gerais / Frequency of helminthes parasites in cats of Uberlândia, Minas Gerais

Necropsies in 50 cats, males and females of different ages were performed from August 2000 to December 2001. Forty five (90 percent) of them had parasites. Eleven cats (22 percent) had single infection, 34 (75.6 percent) multiple infection, and only 5 (10 percent) were free of infection. The parasitic frequencies were as follow: Platynosomum fastosum (40 percent), Ancylostoma braziliensis (38 percent), Physaloptera praeputialis (34 percent), Aelurostrongylus abstrusus (18 percent), Dipylidium caninum (14 percent), Ancylostoma caninum (14 percent), Toxocara mistax (14 percent), Toxocara canis (10 percent), Trichuris campanula (6 percent), Toxascaris leonina (4 percent), Spirometra mansonoides (4 percent), Taenia taeniaeformis (4 percent) e Trichuris vulpis (2 percent).

Freqüência de Giardia spp. por duas técnicas de diagnóstico em fezes de cães / Frequency of Giardia spp. for two diagnosis methods in feces of dogs

One hundred fecal samples from male and female dogs of several ages and breeds were collected in kennels of Uberlândia in Minas Gerais, Brazil. These samples were analyzed to determine the frequency of Giardia spp. using two different diagnostic methods: zinc sulfate flotation technique and merthiolate-iodine-formaldehyde concentration (MIFC). The frequency of giardiasis was 41 percent. Dogs, which were less than 12 months of age, were the most parasitized (68.4 percent). No difference between male and female frequency of giardiasis (31.4 percent and 46.1 percent, respectively) was observed. MIFC detected 38 percent of positive samples and zinc sulfate flotation technique 29 percent. Giardia spp. is present in dogs of Uberlândia's kennels in a high frequency

Ocorrência de Angiostrongylus vasorum no rim de cäo experimentalmente infectado / Occurence of Angiostrongylus vasorum in the kidney of an experimentally infected dog

At the necropsy of a mongrell dog experimentally infected with 450 L3/kg of live weight of Angiostrongylus vasorum, was found in the left kidney, a cyst with 2cm in diameter. Upon examination, a liquid of clear aspect was observed; its density was 1015, eosinophils, neutrophils and protein characterizing transudate. From the cyst, three adult nematodes of 12 to 13 mm, were recuperated, and identified as A. vasorum

Aspectos clínicos de cäes infectados experimentalmente com Angiostrongylus vasorum / Clinical aspects of dogs experimentally inoculated with Angiostrongylus vasorum

Em trabalho experimental, 14 cäes foram inoculados com diferentes números de larvas infectantes de Angiostrongylus vasorum e outros sete mantidos como controle. Durante cinco meses realizaram-se exames clínicos, em intervalos semanais, onde as seguintes características foram analisadas: peso, pulso femural, frequência cardíaca, frequência respiratória, temperatura retal, inspeçäo, auscultaçäo cardíaca e pulmonar e palpaçäo abdominal. Semanalmente foram realizados exames de fezes para determinaçäo do período pré-patente (PPP), que variou de 28 a 108 dias, dependendo do grau de infecçäo inicial. A inoculaçäo provocou aumento no pulso e nas frequências cardíaca e respiratória. O peso dos cäes infectados apresentou-se inferior ao dos cäes controle. As principais alteraçöes clínicas foram: mucosas pálidas, dispnéia, tosse, alteraçöes cardíacas e estertores pulmonares

Efeitos dos viéses de sobrevivência nas prevalências da desnutriçäo em crianças no segundo ano de vida - Brasil, PNSN, 1989 / Effects of survival bias on the prevalence of malnutrition among two-year old children

A análise do crescimento da criança, mensurado por indicadores antropométricos, constitui-se em instrumento importante para avaliaçäo da condiçäo nutricional e do grau de desenvolvimento de uma sociedade. Neste artigo, utiliza-se o indicador P/E, com ponto de corte em - 2 Z, para estimar a prevalência da desnutriçäo em uma populaçäo de crianças no segundo ano de vida. Os dados da Pesquisa Nacional de Saúde e Nutriçäo - PNSN-1989 - foram utilizados para análise da variabilidade da prevalência de acordo com o gênero, renda familiar per capita, regiäo domiciliar e faixa etária trimestral. Baseando-se em estimativas relacionadas às taxas de mortalidade de crianças no primeiro ano de vida, cujas mortes poderiam ser atribuídas à desnutriçäo, aplicou-se a metodologia proposta por Boerma (1992) para corrigir os viéses de sobrevivência. Observou-se que, na faixa de menor renda, as taxas de prevalência de desnutriçäo, no segundo ano de vida passam de 5,5 por cento para 12,9 por cento, correspondendo a aumento de 117.159 desnutridos. Na faixa de maior renda, a variaçäo é de 1,8 por cento para 2,5 por cento, aumento de 6.760 crianças. Já, em relaçäo às regiöes geográficas do Brasil, constatou-se que na regiäo Nordeste a variaçäo foi de 5,2 por cento para 11,7 por cento, correspondendo a um incremento de 82.612 desnutridos. Na regiÒo Sudeste, a variaçäo foi de 1,9 por cento para 3,4 por cento, correspondendo a um aumento de 17.755 crianças desnutridas no segundo ano de vida.