Survey of giardiosis in household and shelter dogs from metropolitan areas of Curitiba, Paraná state, Southern Brazil

Giardia duodenalis is a protozoan parasite that causes a broad range of clinical symptoms varying from none--in asymptomatic carriers--to mild recurring diarrhea consisting of soft, light-colored stools to acute severe diarrhea. In different parts of the world this parasite has raised increased interest due to its possible zoonotic transmission. Among domestic animals, dogs can play an important role in environmental contamination. As there is little information on the frequency of giardiosis in dogs from the Metropolitan Area of Curitiba-State of Paraná, Southern Brazil, the aim of the present work was to evaluate the prevalence of G. duodenalis in two dog populations (household and shelter). To attain the proposed aim, we collected fecal samples from 200 dogs and utilized three diagnostic techniques: Faust's technique (Faust et al. 1939), Benbrook's technique (1963) and polymerase chain reaction (PCR). Faust's technique presented the best results, as it was able to detect a larger number of Giardia cases. Taking Faust's technique as the standard, Benbrook's technique presented 66% sensitivity and PCR demonstrated 69% sensitivity. The shelter dog population showed a 24% occurrence of G. duodenalis while the household population showed a 9% occurrence. Other epidemiological aspects like age, sex, environmental conditions and methodological aspects are discussed in the present article.     

American cutaneous leishmaniasis in horses from endemic areas in the north-central mesoregion of Paraná state, Brazil

American cutaneous leishmaniasis (ACL) is an endemic disease in the north‐west of Paraná state, Brazil, where it occurs in humans and dogs. Few studies have been undertaken on the occurrence of the disease in other domestic animals and horses. In this study we investigated the infection of horses by Leishmania in ACL‐endemic rural areas. Direct agglutination test (DAT) and polymerase chain reaction (PCR) were employed. Fifty‐five horses from rural areas in the municipalities of Doutor Camargo, Ourizona, São Jorge do Ivaí, Ivatuba and Santa Fé (Água do Ó) were analysed. DAT‐detected antibody titres varied from 10 to 640, and 42 (76.3%) animals presented titres ≥20. PCR analyses led to the detection of Leishmania (Viannia) DNA in the blood samples of three (7.1%) of 42 animals. The presence of anti‐L. (V.) braziliensis antibodies and Leishmania (Viannia) DNA in horses from endemic areas suggests their participation in the ACL transmission cycle.     

Prevalence of Neospora caninum antibodies and factors associated with their presence in dairy cattle of the north of Paraná state, Brazil

To determine the prevalence of Neospora caninum antibodies and associated factors, blood sera from 623 female dairy cattle from 23 farms in the north of the state of Paraná, Brazil, were analyzed by means of the indirect immunofluorescent-antibody test (IFAT > or = 25). Serum samples from 134 dogs living on the same farms also were tested for N. caninum antibodies (IFAT > or = 50), and the presence of dogs was associated with the prevalence of N. caninum antibodies in cattle. The overall seroprevalence in cattle was 14.3%, mainly in animals over 24 months of age. Seroprevalence in Holsteins (15.1% of 558) was greater than in mixed-breed cattle (7.7% of 65). Age (> or =24 months) of cattle, feeding silage and/or concentrate produced on the farm were associated; antibodies were found in 21.6% of dogs; and the presence of dogs was associated with the prevalence of N. caninum antibodies in cattle.     

Prevalence of Neospora caninum and Toxoplasma gondii in sheep and dogs from Guarapuava farms, Paraná State, Brazil

Sheep and dog blood samples were collected from nine farms in the county of Guarapuava, Paraná, Brazil. The indirect fluorescent antibody test (IFAT) was used to detect Neospora caninum and Toxoplasma gondii antibodies. Herein, serum samples from 305 sheep were evaluated, being 29 (9.5%) and 157 (51.5%) seropositives to N. caninum and T. gondii, respectively. Seven (29.1%) and five (20.8%) out of 24 dogs were seropositives to N. caninum and T. gondii, respectively. There were no differences among the sheep serology for N. caninum and reproductive problems, management and animal feeding variables, neurological problems and presence of other animals species on the farm (P>or=0.05). The simultaneous frequency of antibodies between N. caninum and T. gondii was 5.2% in the herds. Age, breed, farm size, semi-intensive activity, mineral salt supplementation, water origin, stage of the pregnancy when reproduction problems occurred, neurological problems in lambs, presence of rodents in the food room and pasture cat access were identified as associated factors for the occurrence of toxoplasmosis in sheep (P<0.05). There were no differences among the seropositivity in dogs for N. caninum and T. gondii and breed, age and sex (P>or=0.05). The present work is the first report on serum prevalence of N. caninum in sheep from the state of Paraná, Brazil.     

Relative condition factor and parasitism in anostomid fishes from the floodplain of the Upper Paraná River, Brazil

Individuals of four species of Leporinus were captured in the floodplain of the Upper Paraná River and their metazoan parasites were collected. Fifty-eight taxa of ectoparasites and endoparasites were recorded: 31 in Leporinus lacustris, 32 in Leporinus friderici, 28 in Leporinus obtusidens and 25 in Leporinus elongatus. The aim of this paper was to study the relationship between the host's condition and the parameters of infrapopulations and infracommunities. The health of the host was represented by the relative condition factor (Kn). Richness and number of individuals in the infracommunities of ectoparasites covariated with the Kn of the hosts in one species of fish. Some infrapopulations of ectoparasites covariated negatively and/or the mean Kn of parasitized individuals was lower than those without parasites. The abundance in some infrapopulations of endoparasites covariated positively with the Kn and/or the mean Kn of parasitized fish was better. These results may be related to different transmission strategies used by ecto and endoparasites.     

Diversity of Shiga toxin-producing Escherichia coli in sheep flocks of Paraná State,southern Brazil

Sheep constitute an important source of zoonotic pathogens as Shiga toxin-producing Escherichia coli (STEC). In this study, the prevalence, serotypes and virulence profiles of STEC were investigated among 130 healthy sheep from small and medium farms in southern Brazil. STEC was isolated from 65 (50%) of the tested animals and detected in all flocks. A total of 70 STEC isolates were characterized, and belonged to 23 different O:H serotypes, many of which associated with human disease, including hemolytic-uremic syndrome (HUS). Among the serotypes identified, O76:H19 and O65:H– were the most common, and O75:H14 and O169:H7 have not been previously reported in STEC strains. Most of the STEC isolates harbored only stx1, whereas the Stx2b subtype was the most common among those carrying stx2. Enterohemolysin (ehxA) and intimin (eae) genes were detected in 61 (87.1%) and four (5.7%) isolates, respectively. Genes encoding putative adhesins (saa, iha, lpf_O113) and toxins (subAB and cdtV) were also observed. The majority of the isolates displayed virulence features related to pathogenesis of STEC, such as adherence to epithelial cells, high cytotoxicity and enterohemolytic activity. Ovine STEC isolates belonged mostly to phylogenetic group B1. PFGE revealed particular clones distributed in some farms, as well as variations in the degree of genetic similarity within serotypes examined. In conclusion, STEC are widely distributed in southern Brazilian sheep, and belonged mainly to serotypes that are not commonly reported in other regions, such as O76:H19 and O65:H–. A geographical variation in the distribution of STEC serotypes seems to occur in sheep.     

Cross-sectional serological study of canine Leishmania infection in Fortaleza, Ceará state, Brazil

Visceral leishmaniasis (VL) is one of the most important reemerging parasitic disease in the world. The domestic dog is the main reservoir in urban environments. The aim of this work was to extend the knowledge on canine Leishmania infection in the city of Fortaleza in northeastern Brazil, identifying the risk factors inherent in dog susceptibility to the infection. Two populations were analyzed, domestic dogs from clinics and the Veterinary Hospital Unit of Ceará State University and stray dogs captured by the Center for Zoonosis Control in Fortaleza. Blood samples were collected and centrifuged and the sera were stored at -20 degrees C. ELISA, with soluble crude Leishmania chagasi antigens (LTCC - WDCM731) was used for diagnosis. A total of 1,381 samples were tested, 750 from domestic and 631 from stray dogs. The seroprevalence of canine VL was 21.4% (135/631) in stray dogs and 26.2% (197/750) in domestic dogs. The seroprevalence of Leishmania infection in the six administrative regions of the city (Secretarias Executivas Regionais, or SER) among stray dogs was highest in SER V, representing 31.4% of the cases, with large dogs more infected (27.7%). Among domestic dogs Leishmania infection was most prevalent in SER V (38.5%) and VI (37.6%). The dogs' age (1-6 years), large size, environment with dense vegetation and presence of clinical signs compatible with Leishmania infection were associated with the illness in domestic dogs. The frequency of the infection varied seasonally. The seroprevalence was greatest in July and December. These results confirm Fortaleza is an endemic area for canine VL and suggest some variables associated with increasing infection risk in dog populations.     

Survey of bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Fortaleza, Ceará, Brazil

OBJECTIVE: The ocular microflora in dogs has not been established in north-east Brazil. Thus, the main aim of this research was to determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Fortaleza, Ceará, Brazil. ANIMALS STUDIED: This study included 60 healthy dogs, 15 dogs with unilateral corneal ulcer, and three dogs with bilateral corneal ulcers. Procedure Samples were taken by a calibrated platinum loop (1 microL) placed directly onto the conjunctival sac and on sterile blood agar. The clinical specimens were incubated at 37 degrees C in an atmosphere of 5% CO2 for 48 h. RESULTS: Of the 120 samples from healthy dogs, only 47 (39%) had positive culture for bacteria, while all of the specimens from eyes with corneal ulcer were positive for bacterial growth. The group of dogs with corneal ulcer had a higher (P < 0.05) number of colony-forming units (CFU) per plate than the group of healthy animals. Of the 59 isolates from healthy eyes, only nine (15.3%) had more than 50 CFU per plate, while in the group of dogs with corneal ulcer, 23 (62.2%) of the 37 isolates presented more than 50 CFU per plate. In both groups Gram-positive bacteria (86.5%) predominated over Gram-negative (13.5%). Staphylococcus spp. was the most frequently isolated genus and S. intermedius predominated in both groups. CONCLUSION: The results of our study are directly applicable to initiate rational, preventive and therapeutic measures with greater accuracy in dogs with corneal ulcer.     

Seroepidemiology of Toxoplasma gondii and Neospora caninum in dogs from the state of Paraíba, Northeast region of Brazil

A cross-sectional study was conducted to determine the seroprevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies and to investigate the risk factors related to antibodies against T. gondii and N. caninum in dogs of the city of Campina Grande, state of Paraiba, Northeast region of Brazil. For this purpose, 286 blood samples were collected from dogs during the rabies vaccination campaign, in September 2003, and on this occasion questionnaires addressing epidemiological aspects of the infections were given to each dog owner. The sera were analyzed for anti-T. gondii and anti-N. caninum antibodies by indirect fluorescent antibody tests. Of the total of 286 dogs, 129 were positive for T. gondii (titer16) with a prevalence value of 45.1% (95% CI=39.24-51.07%). For N. caninum, 24 dogs were positive (titer50), with a prevalence value of 8.4% (95% CI=5.45-12.23%). Antibodies to T. gondii and N. caninum were found simultaneously in 14 dogs (4.9%; 95% CI=2.7-8.08%). For T. gondii infection, the risk factors associated with seroprevalence was the age of the animals, with dogs older than one year presenting higher values of odds ratio, and co-habitation of cats in the household. For N. caninum infection, dogs that have street contact had higher odds of seropositivity than dogs that remained exclusively in a domestic environment.     

Sero-epidemiological survey for toxoplasmosis in wild New World monkeys (Cebus spp.; Alouatta caraya) at the Paraná river basin, Paraná State, Brazil

In this study, we captured 60 wild New World monkeys (Cebus spp.; Alouatta caraya) at the Paraná river basin, Paraná State, Brazil, and modified agglutination test (MAT) was performed to evaluate anti-Toxoplasma gondii antibodies. Prevalence was 30.2% (13/43) in Cebus spp. (capuchin monkeys) and 17.6% (3/17) for A. caraya (black and golden howler monkeys). MAT showed antibody titers of 16 (15/16) and 64 (1/16). Herein, we have observed an odds ratio (OR)=4.67 (1.060.05). The present work is the first report on serum occurrence of anti-T. gondii antibodies in wild capuchin monkeys and in wild black and golden howler monkeys.     

Neoechinorhynchus curemai (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus (Osteichthyes: Prochilodontidae) from the Paraná River, Brazil

This work evaluated parasitic infections by Neoechinorhynchus curemai (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus captured between August 2000 and August 2001 in the Paraná River, Presidente Epitácio, S?o Paulo, Brazil. Of 87 fishes examined, 59 were infected (25 males and 34 females). High mean intensities occurred in August 2000 (45.2, range 2-204), September 2000 (28.5, range 11-73), October 2000 (59.3, range 2-250) and February 2001 (27.3, range 3-73). There was no relationship of rainfall with mean intensity and prevalence. Males were more parasitized (P<0.05) than females. This work contributes to the knowledge of helminth parasites of fish from a little studied region of the Paraná River, showing diversity in their fauna when compared to other places in the same river.     

Seasonal dynamics of ticks (Acari: Ixodidae) on horses in the state of São Paulo, Brazil

Natural tick infestations were assessed every 14 days on horses over a 2-year period. Amblyomma cajennense adult ticks were counted individually, without detachment from the horses. Larvae and nymphs of A. cajennense were collected using a rubber scraper that scratched engorged immature ticks from the host. Adult females of Anocentor nitens larger than 4mm length were counted on the horses. Blood samples were also obtained from the horses every 14 days and macroclimatic data were obtained for the study period. Infestations of A. cajennense demonstrated distinct peaks of activity for each of the three parasitic stages over each 12-month period, showing a 1-year generation pattern. Larvae predominated from April to July and nymphs from June to October. Adults predominated from October to March with a greater number of adult males than females. Although other studies on seasonal dynamics in the states of Rio de Janeiro and Minas Gerais were performed with the free-living stages of A. cajennense on pastures, the present study in the state of S?o Paulo, performed with the parasitic stages of A. cajennense on horses, showed similar results to those observed in other states. Infestations by A. nitens demonstrated distinct peaks of activity of adult females (>4 mm), suggesting different tick generations during the year. Infestation with A. nitens was much higher in the first year than the second year which may have been related to horse nutritional status and stocking rate. Although several climatic variables showed statistical significant correlation (r) with tick counts, the determination coefficients (R(2)) were always lower than 0.40, suggesting that any single significant variable (i.e. mean temperature) would not explain the tick distribution pattern over the year. The highest peaks of A. nitens females (>4 mm) were significantly associated with decrease in horse packed cell volumes (R(2)=0.603). The ears and the perineum, tail and groin region accounted for around 70% of all A. nitens females counted on the horses.     

Hepatozoon spp.: report of some cases in dogs in Brasília, Brazil

Canine hepatozoonosis is a disease caused by the tick-borne protozoan Hepatozoon spp. It has been reported in the United States, southern Europe, the Middle East, Africa and the Far East. In Brazil, canine hepatozoonosis is an emerging protozoal tick-borne disease, and is characterized by distinct clinical signs. The objective of this study was to analyze the laboratory findings of some hepatozoonosis cases in dogs in Brasília, Brazil, and their clinical signs. The animals of this experiment showed low parasitemia, similar to H. americanum, but the clinical signs presented were similar to H. canis. According to our observations and in agreement with O'Dwyer et al. [Vet. Parasitol. 94 (2001) 143], the Brazilian Hepatozoon appears more to resemble the species found in the eastern Hemisphere than with H. americanum of North America, or could be caused by a new species. Our data revealed that hepatozoonosis could be considered endemic in Brasília.     

Phylogenetic analysis of Anaplasma marginale strains from Paraná State, Brazil, using the msp1alpha and msp4 genes

Anaplasma marginale is an obligate intraerythrocytic rickettsial pathogen (order, Rickettsiales: family, Anaplasmataceae) that causes bovine anaplasmosis. This disease is widely distributed in tropical and sub-tropical regions of the world and causes important economic losses to cattle production. Major surface protein (MSP)1a (msp1alpha gene) is one of the six MSPs identified on A. marginale from cattle, whose sequence and size vary according to the number of tandem 28- to 29-amino acid repeats. This study characterized the msp1alpha and msp4 genes obtained from three distinct Brazilian herds from the State of Paraná. Three strains of the msp1alpha and one strain of the msp4 gene were sequenced. The strains evaluated revealed PCR products of different size, representing three, five and six internal repeats. Sequence analyses confirmed the number of tandem sequence copies and revealed a high degree of sequence identity with strains from other Brazilian States, as well as strains from the USA, Europe and Israel. The msp1alpha DNA and amino acid sequences from A. marginale and DNA sequences of msp4 strains did not reveal distinct phylogeographical segregation. However, the amino acid sequences of msp4 demonstrated definite phylogeographical relationship. These results suggest that the amino acid sequences of msp4 should be used for phylogenetic identification of A. marginale strains and may be an important tool for the epidemiology and control of anaplasmosis. Additionally, the close similarity of the Paraná strains of A. marginale with strains from USA, Europe and Asia may reflect the introduction of these genes during the development of the Brazilian bovine herd.     

Pulmonary artery dissection causing haemothorax in a cat: potential role of Dirofilaria immitis infection and literature review

A 7-year-old male castrated domestic short-haired cat suddenly died. Gross examination revealed severe right-sided haemothorax with blood clots, four adult filarial nematodes in the blood clots and the caudal vena cava and haemorrhage dissecting into the tunica media of the right pulmonary artery. Histopathological investigation showed fibrosis of the tunica intima and disorganization/fragmentation of the elastic fibres accompanied by fibrous tissue deposition in the tunica media of both branches of pulmonary artery. Degenerative vasculopathy (intimal fibromuscular hyperplasia and medial hypertrophy/hyperplasia) involving pulmonary arteries was also observed. The polymerase chain reaction amplification and sequencing confirmed the identification of the parasite as Dirofilaria immitis. A diagnosis of pulmonary artery dissection with haemothorax and concomitant heartworm disease was formulated. Degenerative processes of the tunica media have been reported to cause pulmonary artery dissection in both humans and animals. Pulmonary artery remodelling induced by heartworms may be considered the underlying cause in the first case of feline pulmonary artery dissection, herein described.     

Occurrence of Neospora caninum antibodies in sera from dogs of the city of São Paulo,Brazil

Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dogs are important in the epidemiology of this parasite because they are the only hosts known to excrete N. caninum oocysts. In order to understand the prevalence of N. caninum in dogs, sera from 500 owned dogs and from over 600 feral street dogs from the city of S?o Paulo, Brazil were assayed for antibodies to N. caninum. Sera were examined by the Neospora agglutination test (NAT) using mouse-derived tachyzoites. Antibodies (> or =1:25) to N. caninum were found in nearly 10% (49/500) of owned dogs and in 25% (151/611) of stray dogs. NAT titers for owned dogs were 1:25 in 28 (5.6%) dogs, 1:50 in 20 (4%) dogs, and > or =1:500 in 1 (0.2%) dog. NAT titers for stray dogs were 1:25 in 79 (12.9%) dogs, 1:50 in 68 (11.1%) dogs, and > or =1:500 in 4 (0.6%) dogs. These data indicate that feral dogs may be important in the epidemiology of N. caninum infection.     

Detection of pseudocowpox virus in water buffalo (Bubalus bubalis) with vesicular disease in the state of São Paulo,Brazil, in 2016

Background: Parapoxviruses are zoonotic viruses that infect cattle, goats and sheep; there have also been reports of infections in camels, domestic cats and seals.

Objective: The objective of this report was to describe a case of vesicular disease caused by pseudocowpox virus (PCPV) in water buffalo (Bubalus bubalis) in Brazil.

Animals: Sixty buffalo less than 6 months old exhibited ulcers and widespread peeling of the tongue epithelium. There were no cases of vesicular disease in pigs or horses on the same property.

Methods: Samples were analysed by PCR and sequencing. Phylogenetic analysis in MEGA 7.01 was reconstructed using major envelope protein (B2L) by the Tamura three-parameter nucleotide substitution model and the maximum likelihood and neighbor joining models, both with 1000 bootstrap replicates. The genetic distance between the groups was analysed in MEGA using the maximum composite likelihood model. The rate variation among sites was modeled using gamma distribution.

Results: The presence of PCPV in the buffalo herd could be demonstrated in epithelium and serum. The minimum genetic distance between the isolated PCPV strain (262-2016) and orf virus and bovine papular stomatitis virus was 6.7% and 18.4%, respectively. The maximum genetic distance calculated was 4.6% when compared with a PCPV detected in a camel.

Conclusions/Clinical Importance: The peculiar position of the isolated strain in the phylogenetic trees does not necessarily indicate a different kind of PCPV that infects buffalo. More samples from cattle and buffalo in Brazil must be sequenced and compared to verify if PCPV from buffalo are genetically different from samples derived from cattle.     

Wasting and mortality in beef cattle parasitized by Eurytrema coelomaticum in the State of Paraná, southern Brazil

A sporadic wasting syndrome affecting beef cattle herds parasitized by Eurytrema coelomaticum is described in the State of Paraná, southern Brazil. The disease was characterized by progressive weight loss, poor body condition despite plenty of good quality forage available, and death. Annual losses ranged from 1 to 3%. The clinical course of the disease varied from 2 to 10 months after the onset of the first clinical signs. At necropsy, one of the three distinct following patterns of lesions were observed: the pancreas was of normal size and color; small, shrunken, white and markedly and diffusely firm (fibrosis); or slightly enlarged and dark with a shriveled capsular surface. Myriads of leaf-shaped trematodes of the genus Eurytrema were packed inside multiple dilated ducts with thickened, whitish fibrous walls, or the flukes were embedded in the remaining pancreatic parenchyma. Microscopic findings included extensive loss of the pancreatic parenchyma with replacement fibrosis, intralesional flukes and eggs, and ductal hyperplasia. Inflammatory reaction varied from absent to severe with the presence of a granulomatous reaction around the trematode eggs. One affected animal had high plasma amylase concentration (1580U/L) suggesting exocrine pancreatic insufficiency. Glucose blood levels were not significantly increased. We suggest that diffuse and marked fibrosis of the pancreas induced by the presence of large amounts of pancreatic flukes is the cause of the sporadic cases of chronic wasting and death of cattle in this geographic area.     

Th1 response in BALB/c mice immunized with Dirofilaria immitis soluble antigens: a possible role for Wolbachia?

The immune response to filarial infection has been shown to be of both the Th1 and Th2 types. Studies aimed at developing immunization strategies against Dirofilaria immitis infection in dogs have shown that protection against larval challenge is of the Th2 type and that several proteins are recognized by immunized or infected animals. The bacterial endosymbiont Wolbachia, harbored by many filarial species including D. immitis, has recently been shown to interact with the host immune system. Specific antibodies to the Wolbachia recombinant surface protein (WSPr) have been observed in cats infected with D. immitis. In this work the authors have determined cytokine production and antibody response in BALB/c mice inoculated with soluble antigens from third stage larvae or from adult worms of D. immitis. Inoculated mice first produced IFN-gamma followed by a peak in IL-4. Specific antibodies to the Wolbachia protein WSPr were exclusively IgG2a, while antibodies against peptides derived from antigens of D. immitis were in the IgG1 and IgE subclasses. The cytokine response is thus similar to that reported for other filarial infection, where Th1 response shifts towards Th2. Antibody response indicates that Wolbachia may induce preferentially a Th1 response during filarial infection, while nematode antigens may be involved in Th2 response. There is thus an overall agreement with current opinions on the role of bacterial versus nematode molecules in driving the response towards the different directions.