Evaluation of neutrophilic function (chemotaxis, phagocytosis and microbicidal activity) in healthy dogs and in dogs suffering from recurrent deep pyoderma.

The modified Boyden's technique of chemotaxis ('leading front' method) and the bacterial killing test with Staphylococcus sp. stained with acridine orange were performed with suspensions of granulocytes from 50 healthy dogs. Lipopolisacharide of Escherichia coli, in normal dog serum was used as the chemotactic factor. The mean value for the chemotactic differential found was 30.41 +/- 12.14 mu. The optimal concentration of bacteria and opsonins (normal dog serum) was 4 and 15%, respectively, and the ideal incubation period was 30 min. The mean values obtained for phagocytosis percentage, number of bacteria per PMN, phagocytosis index and percentage of dead bacteria, were 97.01 +/- 3.22%, 22.20 +/- 4.6, 21.53 +/- 4.50 and 45.30 +/- 9.18%, respectively. Granulocyte functions in 18 dogs with recurrent, chronic, deep pyoderma were assessed by the same methods. No significant difference between the two groups, for any of the evaluated parameters, was found. For elucidation of the pathogenesis of recurrent pyoderma, further studies involving humoral and cellular immunity and the complement system are required.

Hematological changes induced by Bothrops jararaca venom in dogs.

The mechanism of consumption coagulopathy observed in cases of human envenomation by Bothrops jararaca is well established. However, this mechanism may vary according to the animal species studied. In order to study both the clinical and laboratory aspects of bothropic envenomation in dogs, a sublethal defibrinating dose of venom (100 micrograms/kg) was given intravenously. A coagulopathy similar to that observed in humans - including fibrinogen depletion, consumption of factors II, X, V and antithrombin III, and moderate thrombocytopenia - was observed. The presence of circulating activated platelets was also noted. Neutrophilic leukocytosis, lymphopenia, and monocytosis occurred at different times. Erythrocytic values remained normal in dogs treated with B. jararaca venom compared with those treated with saline alone. The erythrocyte sedimentation rate fell rapidly after venom administration and this fall was correlated logarithmically with fibrinogen concentration. Since the effects of envenomation in dogs is similar to that in humans, it was concluded that the dog can be used as a good animal model for studying human venom-induced coagulopathy.

Humoral immunity and reinfection resistance in dogs experimentally inoculated with Babesia canis and either treated or untreated with imidocarb dipropionate.

It is proposed that the chronic asymptomatic carrier state produced by Babesia canis infection could make dogs more resistant against subsequent infections. This suggests that treatment with imidocarb dipropionate, which removes the organism, can make dogs more susceptible to reinfection in a short period of time. Ten male and female dogs of approximately 4-5 months of age were inoculated with B. canis. Half of them received treatment with imidocarb dipropionate (7 mg/kg) on days 15 and 27 post-infection and the other half were untreated. All the animals were examined using clinical and laboratory methods (CBC, platelet counts and serological study by indirect immunofluorescence test) for a 6-month period. Antibodies were first detected on day 7 post-injection and remained at high levels (1:2560) over the period in the non-treated group. This result was significantly different (P<0.001) from the treated group in which antibodies titers declined after day 34 post-infection. Six months later, after a homologous challenge infection only the dogs of treated group showed parasitaemia, thrombocytopenia and splenomegaly, which was significantly different (P<0.05) from the non-treated group. The sterilizing treatment with imidocarb dipropionate was effective in clearing the infection, but inhibited the maintenance of protective antibodies, making the animals more susceptible to reinfection.

Borrelia burgdorferi antibodies in dogs from Cotia county, São Paulo State, Brazil.

Dogs sera samples collected from Cotia County, São Paulo were tested using indirect immunoenzymatic test (ELISA) in order to study Lyme disease serology in dogs. ELISA method was standardized and G39/40 North American strain of Borrelia burgdorferi was used as antigen. Positive results were confirmed employing the Western blotting technique. Because of the possibility of cross-reactions, sera were also tested for different serological strains of Leptospira interrogans and L. biflexa using microscopic sera agglutination test. Twenty-three of 237 (9.7%) serum samples were positive in the ELISA; 20 of them (86.9%) were confirmed by the Western blotting, what suggests that Cotia may be a risk area for Lyme disease. Although 4 samples (1.7%) were positive for Lyme disease and leptospirosis, no correlation was found between the results (X(2) = 0.725; p = 0.394) what suggests absence of serological cross reactivity.

Decreased erythrocyte osmotic fragility during canine leptospirosis.

Erythrocyte osmotic fragility (EOF) was carried out in nineteen dogs naturally infected by Leptospira interrogans serovar icterohaemorrhagiae/copenhagi. A decreased EOF was observed, suggesting a modification of erythrocyte components secondary to disturbances that occur during canine leptospirosis, such as renal damage and hepatic disease.

Toxoplasma gondii infection in Brazilian domestic outpatient cats.

The occurrence of Toxoplasma antibodies in domestic outpatient cats in the city of São Paulo was evaluated using the indirect immunofluorescence assay. A total of 248 blood samples obtained from male and female cats seen at the Veterinary Teaching Hospital at the University of São Paulo between February 1996 and January 1997 were tested. Of these, 17.7% were positive, with a 64 titer being detected in most animals. The frequence of Toxoplasma antibodies was significantly higher in older cats, those fed raw meat and those with free access to the outdoor environment. There was no significant difference in reactivity between males and females. We conclude that diet and free access to the outdoor environment were equally important as predisposing factors to the risk of Toxoplasma infection.

Experimental infection and horizontal transmission of Bartonella henselae in domestic cats.

In order to study B. henselae transmission among cats, five young cats were kept in confinement for two years, one of them being inoculated by SC route with B. henselae (10(5) UFC). Only occasional contact among cats occurred but the presence of fleas was observed in all animals throughout the period. Blood culture for isolation of bacteria, PCR-HSP and FTSZ (gender specific), and BH-PCR (species-specific), as well as indirect immunofluorescence method for anti-B. henselae antibodies were performed to confirm the infection of the inoculated cat as well as the other naive cats. Considering the inoculated animal, B. henselae was first isolated by blood culture two months after inoculation, bacteremia last for four months, the specific antibodies being detected by IFI during the entire period. All contacting animals presented with bacteremia 6 months after experimental inoculation but IFI did not detect seroconversion in these animals. All the isolates from these cats were characterized as Bartonella (HSP and FTSZ-PCR), henselae (BH-PCR). However, DNA of B. henselae could not be amplified directly from peripheral blood by the PCR protocols used. Isolation of bacteria by blood culture was the most efficient method to diagnose infection compared to PCR or IFI. The role of fleas in the epidemiology of B. henselae infection in cats is discussed.

Isolation and partial characterization of Brazilian samples of feline immunodeficiency virus.

Feline immunodeficiency virus (FIV) causes a slow progressive degeneration of the immune system which eventually leads to a disease comparable to acquired immune deficiency syndrome (AIDS) in humans. FIV has extensive sequence variation, a typical feature of lentiviruses. Sequence analysis showed that diversity was not evenly distributed throughout the genome, but was greatest in the envelope gene, env. The virus enters host cells via a sequential interaction, initiated by the envelope glycoprotein (env) binding the primary receptor molecule CD134 and followed by a subsequent interaction with chemokine co-receptor CXCR4. The purpose of this study was to isolate and characterize isolates of FIV from an open shelter in São Paulo, Brazil. The separated PBMC from 11 positive cats were co-cultured with MYA-1 cells. Full-length viral env glycoprotein genes were amplified and determined. Chimeric feline × human CD134 receptors were used to investigate the receptor utilization of 17 clones from Brazilian isolates of FIV. Analyses of the sequence present of molecular clones showed that all clones grouped within subtype B. In contrast to the virulent primary isolate FIV-GL8, expression of the first cysteine-rich domain (CRD1) of feline CD134 in the context of human CD134 was sufficient for optimal receptor function for all Brazilian FIV isolates tested.

[Canine leptospirosis in the state of São Paulo (author's transl)]. / Leptospirose canina em São Paulo.

In this paper the occurrence of leptospirosis was studied by the search of agglutininis antileptospira, in 10 dogs with symptoms of the disease. Another group of 22 animals with hepatic or renal insufficiency was also studied for the correlation between both insufficiency and leptospirosis. Finally, a third group of 40 dogs, clinically normal, was also included in this study. In 60% of suspected cases the clinical diagnosis was confirmed by the presence of specific agglutinins to serotypes icterohaemorrhagiae, canícola, grippotyphosa and bataviae. Among animals with renal or hepatic insufficiency it was found 36.3% of reagents while in the normal group the rate was only 7.5%. The serotype butembo was detected serologically in dogs for the first time in Brazil.

Experimental citrinin nephrotoxicosis in dogs: renal function evaluation.

To assess renal function changes in acute nephrotoxicosis in dogs, the development and evolution of renal damage during induced citrinin intoxication were studied. Six dogs (experimental group) were given 10 mg citrinin/kg/BW every 24 h during 2 d, and 5 dogs (control group) received exclusively the diluent (1 ml 1% sodium carbonate/kg/BW/d for 2 d). The dogs were daily submitted to physical examination, urinalysis and blood biochemistry analyses (blood urea, serum creatinine, potassium, sodium and glucose) during 2 w. The citrinin-induced renal lesions were mainly in the proximal convoluted tubule and characterized by proteinuria, glucosuria and the presence of numerous granular casts in the urine sediment; these could be detected before elevations in blood urea and creatinine. Glucosuria was the earliest abnormality found and lasted 5 d, while proteinuria and cylindruria were observed from days 1 to 5 and from days 1 to 15, respectively. The glomerular filtration rate was slightly affected as observed by blood urea and creatinine elevations from days 2 to 5. Urine analysis is a useful tool for the evaluation of nephrotoxicity since most nephrotoxins act primarily on the proximal convoluted tubule.

Comparative study between microscopic agglutination and complement fixation tests in experimental canine leptospirosis.

In order to evaluate the antibody response to pathologic leptospira from both serovars icterohaemorrhagiae and canicola, dogs were experimentally inoculated with these leptospiras. Each of the serovar were inoculated in 15 dogs and the antibody response in the acute phase of infected was followed by microscopic agglutination and complement fixation tests. Complement fixing antibodies were detected in both groups at the 4th day post infection and agglutinins appeared in circulation at the 7th day post infection when homologous antigens were used. On the 63rd day post infection with serovar canicola and on 56th day post infection with serovar icterohaemorrhagiae, complement fixing antibodies could no longer be detected but, in both experimental groups, specific agglutinins were presented in significant titers.

Prevalence of feline leptospirosis: serologic survey and attempts of isolation and demonstration of the agent.

The occurrence of leptospiral infection in cats was determined through the detection of specific antibodies based on the results of microscopic agglutination test and the attempts of isolation and histological demonstration of leptospires from the kidneys of these animals. Of 172 serum samples examined by microscopic agglutination test, 22 (12.8%) were positive with titers greater than or equal to 100. The most frequent serovar was pomona. In relation to the sex, significant differences were not seen; however the age distribution showed that feline leptospirosis is more frequent in adult cats. The attempts for isolation and demonstration of L. interrogans from renal parenchyma by culture or Warthin Starry technics were unsuccessful.

Use of polymerase chain reaction and enzymatic cleavage in the identification of Helicobacter spp. in gastric mucosa of human beings from North Paraná, Brazil.

Helicobacter pylori is the most common gastric bacteria of human beings. Animal-borne helicobacter have been associated with gastritis, ulceration, and gastric mucosa-associated lymphoid-tissue lymphoma in people. We attempted to identify the species of Helicobacter spp. that infect human beings in north Paran , Brazil. Samples of gastric mucosa from 38 dyspeptic patients were analyzed by optic microscopy on silver stained slides, polimerase chain reaction (PCR), and enzymatic cleavage. Genus and species-specific primers to H. pylori, H. heilmannii, H. felis, and consensual primers to H. bizzozeronii or H. salomonis were used. The PCR products were submitted to enzymatic cleavage by VspI (Helicobacter spp. product) and HinfI (species products) enzymes. Thirty-two out of 38 patients evaluated had 3.2 to 5 m long bacteria that resembled H. pylori in Warthin-Starry stained slides and were positive to the genus Helicobacter by PCR. In 30 of these patients the bacteria were identified as H. pylori. Two samples positive by silver stain were negative to all species tested by PCR. None of the 38 samples was positive to animal-origin helicobacter species. These results show that PCR and enzymatic restriction are practical methods to identify the species of helicobacters present in gastric mucosa of human beings. People in north Paran appear to be infected mostly with H. pylori.

Concentração sérica de paratormônio intacto em cães com insuficiência renal crônica / Serum concentration of intact parathormone in dogs with chronic renal failure

Estudou-se a ocorrência de hiperparatireoidismo secundário renal e determinaram-se as concentrações séricas de paratormônio intacto (PTHi-c), cálcio total e fósforo em 30 cães com insuficiência renal crônica (IRC) e em 40 cães sadios. Para a determinação do PTHi-c, foi utilizado o método imunofluorométrico, com o emprego de anticorpos anti-aminoterminal (extraídos de gema de ovo da galinha) e de anticorpos monoclonais anti-carboxiterminal (H5P10), marcados com Europium. As concentrações séricas de PTHi-c (717,23±469,13pg/ml no grupo IRC e 36,76±34,40pg/ml no grupo-controle; P=0,0001), cálcio total (11,46±2,03mg/dl no grupo IRC e 10,11±0,91mg/dl no grupo-controle; P=0,003) e fósforo (12,01±8,06mg/dl no grupo IRC e 4,33±0,74mg/dl no grupo-controle; P=0,0001) foram mais altas nos cães com IRC. Observou-se estreita correlação entre PTHi-c e fósforo (r=0,56; P=0,0006), o que não ocorreu entre PTHi-c e cálcio. Hipercalcemia em cães com alta concentração de PTHi-c demonstrou a possível ocorrência de hiperparatireoidismo terciário em 11 animais. A hiperfosfatemia pode indicar, de forma indireta, a ocorrência de hiperparatireoidismo secundário nos cães com IRC.

The occurrence of renal secondary hyperparathyroidism was studied and serum intact parathormone (PTHi-c), total calcium and phosphorus were measured in thirty dogs with chronic renal failure (CRF) and in forty healthy dogs. The imunnofluorometric method was used for the PTHi-c assay, using anti-aminoterminal antibodies (obtained from chicken yolk) and anti-carboxiterminal monoclonal antibodies (H5P10), marked with Europium. Mean value ± SD of serum concentration of PTHi-c was 717.23±469.13pg/ml in CRF group and 36.76±34.40pg/ml in control group (P=0.0001); for total calcium it was 11.46±2.03mg/dl in CRF group and 10.11±0.91mg/dl in control group (P=0.003); and for phosphorus it was 12.01±8.06mg/dl in CRF group and 4.33±0.74mg/dl in control group (P=0.0001). The highest values were observed in CRF dogs. A positive correlation between PHTi-c and phosphorus was observed (r=0.56; p=0.0006), and no correlation was detected between PTHi-c and total calcium. In dogs with CRF, hypercalcemia in presence of high level of serum PTHi-c showed a possible indication of tertiary hyperparathyroidism in 11 animals. In conclusion, hyperphosphatemia could indirectly demonstrate the occurrence of secondary hyperparathyroidism in CRF dogs.

Estudo clínico da doença do trato urinário inferior em gatos domésticos de Säo Paulo / Clinical study of lower urinary tract disease of domestic cats of Säo Paulo

O presente estudo teve como objetivos avaliar as principais alteraçöes clínicas, laboratoriais e radiográficas em gatos domésticos com doença do trato urinário inferior (DTUI). Foram utilizados 50 felinos de ambos os sexos, de raças e idades variadas, apresentando como sintomas hematúria, disúria, polaquiúria ou obstruçäo uretral. Estes animais foram inicialmente divididos em dois grupos: o primeiro foi composto por 36 felinos do sexo masculino com obstruçäo uretral e o segundo por 14 felinos, de ambos os sexos, apresentando hematúria, disúria e/ou polaquiúria, mas sem obstruçäo uretral. Utilizou-se também um grupo controle com 25 felinos sadios, de ambos os sexos, raças e idades variadas, alimentados exclusivamente com raçäo seca industrializada. Todos os animais foram submetidos à avaliaçäo das concentraçöes séricas de uréia e creatinina, urinálise, urocultura e urografia excretora. Avaliou-se, ainda, o estado reprodutivo, idade e o tipo de dieta recebida. As alteraçöes observadas mais freqüentemente foram o pH urinário alcalino, cristalúria e espessamento da parede da bexiga. Näo houve diferença significante na ocorrência da doença entre os animais inteiros e castrados. A infecçäo bacteriana constituiu-se em achado esporádico. A metodologia empregada näo foi suficiente para identificar a(s) causa(s) da doença urinária em muitos dos felinos estudados. A diferença do pH urinário entre os animais doentes e sadios, submetidos ao mesmo tipo de dieta, assim como o espessamento da parede da bexiga, identificado nos gatos doentes, merecem destaque e requerem estudos posteriores

Evaluation of preprandial and postprandial serum bile acids and plasma ammonia concentrations in healthy dogs, and the effects of frozen storage on plasma ammonia concentrations

Preprandial and postprandial (2 and 4 hours) serum bile acids (SBA) and pre and postprandial (2 hours) plasma ammonia concentrations were evaluated. Additionally, the effects of freezing (for 24 and 48 hours at -20§C) were observed on plasma ammonia concentrations in 22 healthy dogs. The preprandial SBA concentration was 2.1 ñ 0.3 mmol/l and 7.5 ñ 1.2 mmol/l and 7.8 ñ 1.4 mmol/l for samples obtained 2 and 4 hours after feeding, respectively. Fasting and postprandial (2 hours) plasma ammonia concentrations were significantly different when measurement was performed within 30 minutes after blood collection (118.2 ñ 13.2 mg/dl or 67.3 ñ 7.5 mmol/l and 227.9 ñ 59.2 mg/dl or 129.9 ñ 33.7 mmol/l), but the difference between pre and postprandial concentrations was not observed when ammonia was measured in samples stored (-20§) for 24 and 48 hours. Plasma freezing makes ammonia concentrations fall considerably when these levels were initially too high, mainly in postprandial samples. From these results it may be suggested that canine plasma cannot be stored for later ammonia determination by using freezing as the sole stabilizer, and for SBA determinations, blood samples might be collected 2 or 4 hours after feeding. Plasma ammonia values obtained in this study should allow comparisons to data obtained from dogs with hepatic disease or hepatoencephalopathy, so as to confirm the importance of its use as means of diagnosis and prognosis in future

Ocorrência de anticorpos antitoxoplasma em gatos infectados naturalmente pelo vírus da imunodeficiência dos felinos / Ocurrence of antibodies to Toxoplasma in cats naturally infected with feline immunodeficiency virus

Foram avaliadas, pela técnica de imunofluorescência indireta, a freqüência e a magnitude dos títulos de anticorpos antitoxoplasma (Toxoplasma gondii, Nicolle; Manceaux, 1909), em gatos infectados naturalmente pelo vírus da imunodeficiência dos felinos (VIF). Utilizaram-se 115 amostras de soro sangüíneo de gatos negativos ao vírus da leucemia felina que foram divididas em 3 grupos. Os 22 animais do grupo I eram positivos ao VIF. Os 58 animais que compuseram o grupo II eram doentes porém negativos na pesquisa de anticorpos anti-VIF e os 35 felinos do grupo III em hígidos e negativos ao VIF. Os resultados obtidos permitiram concluir que a freqüência de anticorpos antitoxoplasma foi maior no grupo I do que nos grupos II e III. A análise estatística mostrou forte associaçäo entre a infecçäo pelo VIF e a presença de anticorpos antitoxoplasma. Näo se observou diferença entre a magnitude dos títulos de anticorpos antitoxoplasma nos animais positivos e negativos ao VIF. Embora gatos que desenvolvam imunidade raramente eliminem oocistos, näo se sabe exatamente como esta imunidade pode influenciar a eliminaçäo de oocistos naqueles gatos infectados pelo VIF. Em face da alta freqüência de anticorpos antitoxoplasma observada nos animais positivos ao VIF, acredita-se que todos os gatos positivos a esse vírus devam ser avaliados quanto à presença de anticorpos antitoxoplasma