Clinical and electrocardiographic evaluation during experimental toad poisoning in dogs

Accidents involving toad poisoning are frequent and dogs are the most common victims; they become poisoned by biting or ingesting a toad. When released in the organism, the venom is absorbed by both the oral mucosa and the digestive tract, initiating its toxic action. The aim of this work was to evaluate the clinical and electrocardiographic aspects of dogs subjected to experimental toad poisoning, as well as their response to treatment with propranolol. Twenty dogs were divided into two groups, a control group (n = 5) and a poisoned group (n = 15). After general anesthesia, the control group received a placebo, while the poisoned group received a venom aliquot through an orogastric tube. Results were tested through multivariate analysis (p < 0.05). The animals in the poisoned group had gastrointestinal symptoms including emesis, intense salivation, hyperemic or congested oral mucosa and pasty diarrhea. Non-responsive mydriasis, nystagmus, depression, stupor, tachypnea, opisthotonus and ataxia were also manifested by 100% of the poisoned animals. Affected dogs had an increase in blood pressure, statistically significant throughout study. Five poisoned animals developed ventricular tachycardia and were treated with propranolol (0.5 mg/kg IV). All propranolol-treated animals returned to normal sinus rhythm, which evidences the efficacy of this drug to treat ventricular arrhythmias caused by toad venom.

Active surveillance of canine visceral leishmaniasis and american trypanossomiasis in rural dogs from non endemic area

A leishmaniose visceral canina (LVC) e a tripanossomíase americana são importantes zoonoses para a saúde pública que encontram no cão o principal reservatório doméstico para o homem. O trabalho procurou estimar a prevalência de anticorpos circulantes anti-Trypanosoma cruzi e anti-Leishmania spp., em amostras de cães provenientes da zona rural do município de Botucatu, SP. Durante a campanha de vacinação antirrábica canina da zona rural do município, foram coletadas 689 amostras de soro e processadas pela técnica de imunofluorescência indireta. Os testes sorológicos revelaram a ausência de anticorpos anti-Leishmania spp. e, na pesquisa dos anticorpos anti-T. cruzi, foram detectados 3 (0,4%) cães.

Spatial Distribution of Seropositive Dogs to Leptospira spp. and Evaluation of Leptospirosis Risk Factors Using a Decision Tree

Background: Leptospirosis is an important zoonotic disease associated with poor areas of urban settings of developing countries and early diagnosis and prompt treatment may prevent disease. Although rodents are reportedly considered the main reservoirs of leptospirosis, dogs may develop the disease, may become asymptomatic carriers and may be used as sentinels for disease epidemiology. The use of Geographical Information Systems (GIS) combined with spatial analysis techniques allows the mapping of the disease and the identification and assessment of health risk factors. Besides the use of GIS and spatial analysis, the technique of data mining, decision tree, can provide a great potential to find a pattern in the behavior of the variables that determine the occurrence of leptospirosis. The objective of the present study was to apply Geographical Information Systems and data prospection (decision tree) to evaluate the risk factors for canine leptospirosis in an area of Curitiba, PR.Materials, Methods & Results: The present study was performed on the Vila Pantanal, a urban poor community in the city of Curitiba. A total of 287 dog blood samples were randomly obtained house-by-house in a two-day sampling on January 2010. In addition, a questionnaire was applied to owners at the time of sampling. Geographical coordinates related to each household of tested dog were obtained using a Global Positioning System (GPS) for mapping the spatial distribution of reagent and non-reagent dogs to leptospirosis. For the decision tree, risk factors included results of microagglutination test (MAT) from the serum of dogs, previous disease on the household, contact with rats or other dogs, dog breed, outdoors access, feeding, trash around house or backyard, open sewer proximity and flooding. A total of 189 samples (about 2/3 of overall samples) were randomly selected for the training file and consequent decision rules. The remained 98 samples were used for the testing file. The seroprevalence showed a pattern of spatial distribution that involved all the Pantanal area, without agglomeration of reagent animals. In relation to data mining, from 189 samples used in decision tree, a total of 165 (87.3%) animal samples were correctly classified, generating a Kappa index of 0.413. A total of 154 out of 159 (96.8%) samples were considered non-reagent and were correctly classified and only 5/159 (3.2%) were wrongly identified. on the other hand, only 11 (36.7%) reagent samples were correctly classified, with 19 (63.3%) samples failing diagnosis.Discussion: The spatial distribution that involved all the Pantanal area showed that all the animals in the area are at risk of contamination by Leptospira spp. Although most samples had been classified correctly by the decision tree, a degree of difficulty of separability related to seropositive animals was observed, with only 36.7% of the samples classified correctly. This can occur due to the fact of seronegative animals number is superior to the number of seropositive ones, taking the differences in the pattern of variable behavior. The data mining helped to evaluate the most important risk factors for leptospirosis in an urban poor community of Curitiba. The variables selected by decision tree reflected the important factors about the existence of the disease (default of sewer, presence of rats and rubbish and dogs with free access to street). The analyses showed the multifactorial character of the epidemiology of canine leptospirosis.

Molecular identification of Cryptosporidium spp. from fecal samples of felines, canines and bovines in the state of São Paulo, Brazil

The objective of this study was to obtain information of epidemiological nature through genotypic characterization of Cryptosporidium isolates from dogs, cats and bovines from the state of São Paulo, Brazil. The extraction of DNA from oocysts was carried out and polymerase chain reaction was accomplished using specific primers to 18S rRNA gene. The amplicons were directed sequenced. Seven cat samples, nine dog samples and nine bovine samples were analysed. From the seven cat samples the genotypic analyses revealed Cryptosporidium felis in all. These were the first genotypic characterization of Cryptosporidium from domestic felines in Brazil. In nine sequenced samples from dogs, genotypic identities compatible with Cryptosporidium canis were revealed in all samples. The genotypic analyses in bovines revealed Cryptosporidium parvum in eight samples and Cryptosporidium bovis in another sample, the last one being a non-zoonotic species, not related to clinical symptoms and described for the first time in Brazil. (c) 2007 Elsevier B.V. All rights reserved.

Effects of topical levobunolol or fixed combination of dorzolamide-timolol or association of dorzolamide-levobunolol on intraocular pressure, pupil size, and heart rate in healthy cats

Estudaram-se e compararam-se os efeitos do levobunolol, da combinação fixa de dorzolamida 2%-timolol 0,5% e da associação de dorzolamida 2% com levobunolol 0,5% sobre a pressão intra-ocular (PIO), o diâmetro pupilar (DP), a freqüência cardíaca (FC) e a hiperemia conjuntival em 18 gatos saudáveis. PIO, DP, FC e hiperemia conjuntival foram aferidos diariamente, em três horários distintos (9h, 14h e 18h). Três grupos foram formados (n=6) e um olho de cada animal recebeu, aleatoriamente, uma gota de levobunolol (L), ou a combinação comercial à base de dorzolamida-timolol (DT), ou a associação de dorzolamida com levobunolol (DL). Parâmetros basais foram aferidos no primeiro dia (dia 0). Nos quatro dias consecutivos, os fármacos foram instilados às 8h e 20h e os parâmetros aferidos nos mesmos horários. Todos os parâmetros decresceram significativamente em relação aos valores basais (P<0,001) e não se observou hiperemia conjuntival. O levobunolol reduziu significativamente a PIO, o DP e a FC e o foi o fármaco que mais reduziu a FC. Não se observou efeito sinérgico na redução da PIO quando a dorzolamida foi adicionada ao levobulol.

Immunisation of dogs and guinea pigs against Rhipicephalus sanguineus ticks using gut extract

Tick-bite naive guinea pigs were inoculated three times with Rhipicephalus sanguineus gut or salivary gland extracts and saponin as adjuvant. Dogs were inoculated three times with gut extract only as this fraction induced a more efficient resistance in guinea pigs (lower tick recovery and lower engorged female weights). Freund's adjuvant and saponin were used as adjuvants for the immunisation of dogs. Freund's adjuvant was used to enhance cellular immunity. The highest level of resistance in dogs was induced by the immunisation with gut extract and Freund's adjuvant. Many female ticks from dogs immunised this way engorged fully but died prior to oviposition. Resistant guinea pigs and dogs seemed to trigger different immune mechanisms against R. sanguineus ticks as damage to parasites also differed. A major role for cellular immunity in the resistance of dogs against R. sanguineus ticks is suggested. Resistance mechanisms against R. sanguineus ticks is discussed.

IgG subclass profile of serum antibodies to Leishmania chagasi in naturally infected and vaccinated dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

T and B lymphocytes in the brains of dogs with concomitant seropositivity to three pathogenic protozoans: Leishmania chagasi, Toxoplasma gondii and Neospora caninum

Background: Visceral leishmaniasis is a disease with great variability regarding the clinical manifestations in humans and dogs. Chronically infected dogs may develop neurological disorders, however, there are few reports that characterize the lesions and make clear the pathogenesis of the canine cerebral leishmaniasis. Concomitant with Leishmania chagasi, dogs may be infected by opportunistic pathogens, such as Toxoplasma gondii and Neospora caninum, which may contribute to the occurrence of lesions in the central nervous system. Hence, we aimed to compare the T and B lymphocytes population in the brains of infected dogs with seropositivity to L. chagasi, T. gondii and N. caninum concurrently (n = 24), seropositivity only to L. chagasi (n = 31), and seropositivity to T. gondii and N. caninum (n = 16). Uninfected dogs were used as control (n = 10). Results: Inflammatory lesions, characterised by mononuclear cell accumulation, composed mainly of CD3+ T lymphocytes predominated in several encephalic regions of the dogs from all the three infected groups, with no difference among them (P = 0.0004), whereas CD79α+ B lymphocytes were detected in very small intensity and presented no difference among groups (P = 0.5313). Furthermore, no association among diseases was detected at the serological enquire. Conclusions: We demonstrate that the peripheral infection by L. chagasi per se can promote the influx of lymphocytes within the nervous milieu as occurs during Toxoplasma and Neospora infections, and the concomitant seropositivity against these pathogens does not exacerbate the inflammatory brain lesions. Therefore, these findings give additional support that the brain should be included in the list of organs affected by visceral leishmaniasis and that even asymptomatic infected dogs may develop brain lesions. © 2013 Sakamoto et al.; licensee BioMed Central Ltd.

Predictive formulas for food base excess and urine pH estimations of cats

Food base excess (BE, mEq/kg) can be calculated from the diet macroelements, together with either the sulfur amino acids methionine and cysteine (BEaa) or total sulfur (BEs) concentrations. The present study compared the use of sulfur or methionine and cysteine for calculating the food BE (experiment 1) and investigated the influence of food BE on blood gas analysis and the urine pH of cats, and proposes a prediction equation to estimate the urine pH of cats fed kibble diets based on the calculated food BE (experiments 2 and 3). In experiment 1, nine healthy, adult cats were used in a change-over design and fed with nine commercial dry cat foods. The cats were housed in metabolism cages over seven days for adaptation and three days for total urine collection. All of the urine produced over 24h was pooled by cat and diet. The cats' acid-base status was assessed through blood gas analysis after 10 days of diet consumption. A mean difference of -115mEq/kg between BEs and BEaa was observed, which could be explained by a greater concentration of sulfur in the whole diet than in methionine and cysteine. Urine pH presented a stronger correlation with food BEs (R2=0.95; P<0.001) than with food BEaa (R2=0.86; P<0.001). Experiment 2 included 30 kibble diets, and each diet was tested in six cats. The food BEs varied between -180 and +307mEq/kg, and the urine pH of the cats varied between 5.60 and 7.74. A significant correlation was found between the measured urine pH and the food BEs (urinary pH=6.269+[0.0036×BEs]+[0.000003×BEs2]; R2=0.91; P<0.001). In experiment 3, eight kibble diets were tested (food BEs between -187mEq/kg and +381mEq/kg) to validate the equation proposed in experiment 2 and to compare the obtained results with previously published formulae. The results of the proposed formula presented a high concordance correlation coefficient (0.942) and high accuracy (0.979) with the measured values, and the estimates of urine pH did not differ from the values obtained in cats (P>0.05). The cats' venous blood pH, bicarbonate, and blood BE were correlated with food BEs (P<0.001); the consumption of diets with low food BEs induced a reduction in these parameters. In conclusion, food macroelement composition has a strong influence on cats' acid-base equilibrium and food BEs calculation is a useful tool to formulate and balance kibble diets for felines. © 2013 Elsevier B.V.

Prevalence of Toxoplasma gondii and Leishmania spp. infection in cats from Brazil

A total of 386 feline blood samples from Brazil were collected and analyzed by the indirect immunofluorescence antibody test (IFAT) for the presence of Toxoplasma gondii and Leishmania spp. antibodies. Specific antitoxoplasma IgG were found in 63 of 386 (16.3%) cats and immunoglobulin G against Leishmania spp. was detected in two serum samples. The overall prevalence was significantly higher in adult cats than in juvenile cats for T. gondii infection. There were no significant differences between positivity and gender or breed. The frequency of T. gondii antibodies found in domestic cats of Brazil suggests active transmission within an urban environment. This study proved the occurrence of two important protozoan zoonosis in felines from Brazilian endemic area for visceral leishmaniasis. © 2013.

Effects of P-MAPA immunomodulator on Toll-like receptor 2, ROS, nitric oxide, MAPKp38 and IKK in PBMC and macrophages from dogs with visceral leishmaniasis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Blood and seminal plasma concentrations of selenium, zinc and testosterone and their relationship to sperm quality and testicular biometry in domestic cats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pharmacokinetics and pharmacodynamics of the glucagon-like peptide-1 analog liraglutide in healthy cats

Glucagon-like peptide-1 (GLP-1) is an intestinal hormone that induces glucose-dependent stimulation of insulin secretion while suppressing glucagon secretion. Glucagon-like peptide-1 also increases beta cell mass and satiation while decelerating gastric emptying. Liraglutide is a fatty-acid derivative of GLP-1 with a protracted pharmacokinetic profile that is used in people for treatment of type II diabetes mellitus and obesity. The aim of this study was to determine the pharmacokinetics and pharmacodynamics of liraglutide in healthy cats. Hyperglycemic clamps were performed on days 0 (HGC) and 14 (LgHGC) in 7 healthy cats. Liraglutide was administered subcutaneously (0.6 mg/cat) once daily on days 8 through 14. Compared with the HGC (mean +/- standard deviation; 455.5 +/- 115.8 ng/L), insulin concentrations during LgHGC were increased (760.8 +/- 350.7 ng/L; P = 0.0022), glucagon concentrations decreased (0.66 +/- 0.4 pmol/L during HGC vs 0.5 +/- 0.4 pmol/L during LgHGC; P = 0.0089), and there was a trend toward an increased total glucose infused (median [range] = 1.61 (1.11-2.54) g/kg and 2.25 (1.64-3.10) g/kg, respectively; P = 0.087). Appetite reduction and decreased body weight (9% +/- 3%; P = 0.006) were observed in all cats. Liraglutide has similar effects and pharmacokinetics profile in cats to those reported in people. With a half-life of approximately 12 h, once daily dosing might be feasible; however, significant effects on appetite and weight loss may necessitate dosage or dosing frequency reductions. Further investigation of liraglutide in diabetic cats and overweight cats is warranted. (C) 2015 Elsevier Inc. All rights reserved.

Pulmonary function in obese vs non-obese cats

Obesity is a risk factor in the development of several respiratory diseases. Lung volumes tend to be decreased, especially expiratory reserve volume, increasing expiratory flow limitation during tidal breathing. Barometric whole-body plethysmography is a non-invasive pulmonary function test that allows a dynamic study of breathing patterns. The objective of this study was to compare pulmonary function variables between obese and non-obese cats through the use of barometric whole-body plethysmography. Nine normal-weight and six obese cats were placed in the plethysmograph chamber, and different respiratory variables were measured. There was a significant decrease in tidal volume per kilogram (P=0.003), minute volume per kilogram (P=0.001) and peak inspiratory and expiratory flows per kilogram (P=0.001) in obese cats compared with non-obese cats. Obesity failed to demonstrate a significant increase in bronchoconstriction index variable enhanced pause (Penh), as previously reported in humans and dogs. The results show that feline obesity impairs pulmonary function in cats, although a significant increase in bronchoconstriction indexes was not observed. Non-invasive barometric whole-body plethysmography can help characterise mechanical dysfunction of the airways in obese cats.

Prevalence and geographical distribution of Toxoplasma gondii in dogs in the urban area of Botucatu, SP, Brazil

Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii, and can infect a wide variety of animals including humans. Domestic animals can be an important sentinel population for infection in the community. Occurrence of T. gondii infection was assessed in dogs in the urban area of Botucatu city, SP, Brazil. In the sample, 10% rate for error estimate, 95% confidence interval, and 5% significance level were established. Serum samples were collected from dogs during a rabies vaccination campaign, and were processed using modified agglutination test (MAT). Blood samples were collected from 670 dogs, with homogeneous distribution in five regions in the urban area, representing 3.74% of 17,910 animals vaccinated. In this sample, 17.3% (116/670) dogs (68 – 58.6% female and 48 – 41.4% male) were positive for T. gondii infection (p<0.03). Regarding age of the infected dogs 4.6% (4/88) were younger and 95.4% (84/88) were older than one year (p<0.01); the age of 28 positive animals were undetermined. The serum titers of anti-T. gondii antibodies were: 16 (69.8%; 81/116), 64 (13.8%; 16/116), 256 (15.5%; 18/116), and 1024 (0.9%; 1/116). Prevalence was distributed among the North 14.2% (19/134), South 18.0% (31/172), East 15.7% (19/121), West 21.6% (27/125), and Central 16.9% (20/118) regions of the municipality (p=0.5). In all these regions, females and dogs aged more than one year showed a higher occurrence of T. gondii infection (p<0.05).