In vitro isolation and seroprevalence of Toxoplasma gondii in stray cats and pigeons in Lisbon, Portugal

Oral contamination with Toxoplasma gondii oocysts shed by cats into the environment has been linked to severe outbreaks of human toxoplasmosis. Pigeons (Columba livia) are highly susceptible to oral infection with oocysts and indirectly indicate soil contamination, since they feed from the ground. A seroprevalence study was performed on cats and pigeons captured in the city of Lisbon. Serum samples collected from 1507 pigeons captured at 64 feeding sites and 423 stray cats were screened for antibodies anti-T. gondii using a commercial direct agglutination test. Seroprevalence in pigeons was 2.6% (39/1507) (95% CI: 1.9-3.5%) and 37.5% (24/64) of pigeon flocks sampled showed to be infected with T. gondii. The proportion of infected pigeons within seropositive flocks ranged between 4.8% and 21.1%. Among cats, seroprevalence was 44.2% (187/423) (95% CI: 39.5-49.1%). Isolation of T. gondii from animal tissues was attempted by in vitro assay. Inoculation of brain homogenates from 20 pigeons and 56 cats into Vero cell cultures allowed isolation of T. gondii from 13 pigeons (65%) and 15 cats (26.8%). Inoculation of muscle homogenates (heart and limbs) prepared by acid-peptic digestion from a subset of 15 cats resulted in the recovery of T. gondii from 10 cats (66.7%).     

Prevalence study of the lungworm Aelurostrongylus abstrusus in stray cats of Portugal

In this study we have investigated the prevalence of aelurostrongylosis, one of the most common feline pulmonary parasitic diseases, in cats from the north-west region of Portugal. For this purpose, 97 faecal samples were collected from cats at risk of being infected by Aelurostrongylus abstrusus in an animal shelter and in a municipal facility. Using the Baermann-Wetzel coprological technique, faecal shedding of first stage larvae (L1) was detected in 17.4% of the cats. Based on this result, it can be concluded that this lungworm infection seems to be common among feral cats in the north-west region of Portugal, in spite of the fact that clinical aelurostrongylosis is not frequently diagnosed by feline practitioners in the area. This parasitic disease should be included in the differential diagnosis of cats presenting with coughing or dyspnoea, and it also should be extended to asymptomatic animals with pulmonary nodules detected by image diagnosis.     

Prevalence of infectious diseases in feral cats in Northern Florida

Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.     

Serologic prevalence of selected infectious diseases in cats with uveitis.

Serologic evidence of infection by Toxoplasma gondii, feline leukemia virus, feline coronaviruses, or feline immunodeficiency virus (FIV) is commonly found in cats with uveitis. Serum samples from 124 cats with uveitis were assayed by use of ELISA for the detection of T gondii-specific immunoglobulin M (IgM), IgG, and circulating antigens (Ag), as well as an ELISA for feline leukemia virus Ag, an ELISA for antibodies to FIV, and an indirect fluorescent antibody assay for antibodies to feline coronaviruses. Serologic evidence of infection by 1 or more of the infectious agents was detected in 83.1% of the samples. Serologic evidence of T gondii infection, defined as the detection of T gondii-specific IgM, IgG, or Ag in serum, was found in 74.2% of the samples. The seroprevalence of T gondii infection was significantly greater in cats with uveitis than in healthy cats from a similar geographic area. Serum samples from cats with serologic evidence of both T gondii and FIV infections were more likely to contain T gondii-specific IgM without IgG than samples from cats with serologic evidence of T gondii infection alone. Cats with serologic evidence of FIV and T gondii coinfection had a higher T gondii-specific IgM titer geometric mean and a lower T gondii-specific IgG titer geometric mean than did cats with serologic evidence of T gondii infection alone. Serologic evaluation for T gondii infection should include assays that detect IgM, IgG, and Ag, particularly in cats coinfected with FIV.     

Feline immunodeficiency virus testing in stray, feral, and client-owned cats of Ottawa

Feline immunodeficiency virus (FIV) seroprevalence is evaluated in 3 groups of cats. Seventy-four unowned urban strays were tested, as well as 20 cats from a small feral cat colony, and 152 client-owned cats. Of the 246 cats tested, 161 (65%) were male and 85 (35%) were female. Seroprevalence for FIV was 23% in the urban strays, 5% in the feral cat colony, and 5.9% in the client-owned cats. Ten cats (4%) were also positive for Feline leukemia virus (FeLV) antigen, including 2 cats coinfected with FeLV and FIV. Seroprevalence for FIV in cats from Ottawa is similar to that found in other nonrandom studies of cats in North America.     

Virological Survey in free-ranging wildcats (Felis silvestris) and feral domestic cats in Portugal

To determine the presence of viral pathogens in natural areas a survey was conducted on an opportunistic sample of fifty eight wild (Felis silvestris silvestris) and feral cats (F. s. catus). The biological materials included serum, lung tissue extract and stool. Feline leukemia virus p27 antigen was detected in 13/50 serum/lung tissue extract samples (26%), canine distemper virus antibodies were detected in 2/26 serum/lung tissue extract samples (7.7%), feline coronavirus RNA was present in 6/29 stool samples (20.7%) and feline parvovirus DNA in 2/29 stool samples (6.9%). Canine distemper virus RNA was not detected. Feline immunodeficiency virus and feline coronavirus antibodies were not detected. Evidence of exposure to feline leukemia virus, canine distemper virus, feline coronavirus and feline parvovirus was found in wild and feral cats raising the importance of performing a comprehensive survey to correctly evaluate the potential threat of infectious diseases to endangered species, namely to the wildcat and to the Iberian lynx, which is meant to be reintroduced after 2012 in Portugal.     

Prevalence of Toxoplasma gondii antibodies in stray cats in Sari, northern Iran

Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete environmentally resistant oocysts. T.gondii is a major zoonotic agent which infects up to one-third of the world population. Toxoplasmosis in neonates and immunocompromised patients can lead to severe disease and death. A cross- sectional parasitological and serological survey with latex agglutination test (LAT) to detect anti-T. gondii antibodies was conducted on 100 serum samples collected from stray cats in five urban areas of Sari, Northern Iran, from April to November 2004. Classification by age, sex, weight, season and region was made. Results analyzed according to specific variables. The overall prevalence of T. gondii IgG antibodies (LAT titre ≥1:1) were found in 40 of 100(40%) of stray cats, with regional variations. Overall 16 of 100(16%) of stray cats had diagnostically significant antibody titres (LAT ≥ 1:64). Prevalence was significantly higher in adult cats (1.5–3.0 kg, 54.5% of 66) than in juvenile cats and kittens (≤1.4 kg, 11.8% of 34) and higher in female stray cats (44.4% of 72) than in male stray cats (28.6% of 28). Toxoplasma seroprevalence was highest in the season of spring (22.4%). There was a significant difference in the prevalence of infection relative to host age and weight (P < 0.05). No significant difference was found between the prevalence of infection relative to host gender, urban sites and season (P > 0.05). Prevalence of T. gondii oocyst was also analyzed by a routine coprological method in 100 cats. T. gondii oocysts were not found in any faecal samples analyzed. Only 2 out of 100 smear preparations of intestinal mucosa showed trophozoites of T. gondii.     

Seroprevalence of Toxoplasma gondii antibodies in stray cats and dogs in the Bangkok metropolitan area, Thailand

Cats and dogs are the most popular pet animals worldwide. Cats are the natural reservoir of Toxoplasma gondii and excrete the resistant oocyst to environments. On the other hands, dogs play a role in the mechanical transmission of the parasite. Stray cats and dogs in the Bangkok metropolitan area are becoming a public concern because there is a considerable increase in their number annually. These facts indicate the risk of mechanically spreading zoonoses including toxoplasmosis to humans since human acquire the infection from infected mammals, either directly or indirectly. In the present study, the presence of T. gondii antibodies was examined in 592 cats and 427 dogs from October 2001 to September 2002 by using a latex agglutination test. T. gondii antibodies were detected in 65 (11.0%) of the 592 cats and 40 (9.4%) of the 427 dogs. The antibody titers in the positive animals ranged from 1:64 to 1:2048. Seroprevalence was significantly higher in female cats than in male cats. The present study suggested that T. gondii was widespread in the stray animals in the Bangkok metropolitan area; therefore, it is essential to control the number of stray cats and dogs in order to reduce the transmission of toxoplasmosis to animals and humans.     

Indirect detection of the infectious agents of selected parasitic diseases in animals by immunologic and molecular biological methods

In this review the following possibilities of indirect detection of causal agents in selected animal parasitoses are discussed: Detection of serum antibodies by ELISA, IFAT and other test systems in leishmaniasis of dogs, babesiosis of horse, cattle and dog, and in toxoplasmosis of cat and various intermediate host species. In leishmaniasis of dogs the specificity of serodiagnosis can be improved by additional Western-Blot analysis. New approaches are provided by the detection of antigens circulating in serum (i.e. in dirofilariasis of dogs) or excreted in faeces (copro-antigens) (i.e. in intestinal parasitoses). Some of the last mentioned techniques are still under evaluation. A new trend in the diagnosis of parasitoses is the application of DNA technologies for the specific identification of causal agents. Some examples are discussed.     

Radiographic measurement of vertebral heart size in healthy stray cats

The aims of this study were to determine vertebral heart size (VHS) in stray cats and to compare different radiographic views. This study was performed on 50 adult stray cats. All cats were short-haired and non-obese and were considered to be healthy based on physical examination and electrocardiography. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken. The long and short axes of the heart were measured in millimetres. The thoracic vertebral length spanned by each dimension was measured caudally from the fourth thoracic vertebra. Mean+/-SD and the correlation coefficient between the measurements were calculated with standard statistical software. The sum of the long and short axes of the heart expressed as VHS was 7.3+/-0.49 vertebrae in right lateral, 7.3+/-0.55 vertebrae in left lateral, 7.5+/-0.68 vertebrae in dorsoventral and 7.5+/-0.53 vertebrae in ventrodorsal. The differences between right and left lateral as well as dorsoventral and ventrodorsal views were not significant (P>0.05). Absolute measurements and vertebral heart scale values were slightly smaller than those reported in the literature for mixed population of cats. It is, therefore, important to take the breed in to account.     

Seroprevalence of Toxoplasma gondii infection in stray and household cats in Tehran

The prevalence of anti-Toxoplasma gondii specific IgG in stray and household cats in Tehran was determined by Indirect Fluorescent Antibody Test (IFAT) on serum samples from 100 cats (50 stray and 50 households). Overall infection rate was 63%. The infection rate in stray cats (90%) was significantly higher (p<0.001) than that of household cats (36%). Last serum positive dilutions varied from 1: 32 to 1: 512 titres in which the highest percentage (27%) was for 1:256 and the least (4.8%) was at 1:32. The rate of infection between male and female cats of both groups was not significantly different; 90.3% versus 89.5% for male and female in stray cats, respectively. Different sexes of household cats were seropositive at the same rate (36%). A high positive correlation (r(2)=0.97) between age and the rate of infection was observed. The prevalence of Toxoplasma gondii infection in cats in Tehran was high, especially in stray cats which are probably the main source of Toxoplasma infection in this area.     

A brief review of infectious and parasitic diseases of wapiti, with emphasis on western Canada and the northwestern United States

In this paper I review diseases reported in both captive and free-ranging wapiti in western North America, with some reference to diseases in captive red deer in Great Britain, Europe, New Zealand, and eastern North America.

With the exception of coronavirus in neonates, few viral agents are reported to cause serious disease losses in wapiti in North America at this time. Bacterial diseases of current significance include brucellosis (focus in Wyoming), clostridial diseases, coliform enteritis of neonates, pasteurellosis, and necrobacillosis. The endoparasites most likely to be seen causing lesions in wapiti of western North America are lungworm (Dictyocaulus viviparus), arterial worm (Elaeophora schneideri), and, possibly, liver fluke (Fascioloides magna). Ectoparasites of importance to wapiti are Psoroptes cervinus and Dermacentor albipictus. Nutritional diseases are not covered in this review.

     

Frequency of blood type A, B, and AB in 515 domestic shorthair cats from the Lisbon area

Background: The A, B, and AB feline blood types are recognized worldwide and their frequencies vary geographically and among breeds. Frequencies of feline blood types have been reported previously from northern Portugal; however, they are unknown in other parts of the country. Objectives: This 13‐year retrospective study was undertaken to determine the frequency of feline blood types in domestic shorthair (DSH) cats from the Lisbon area of central Portugal. Methods: Blood samples were obtained at the Veterinary Teaching Hospital of the Technical University of Lisbon and its Veterinary Blood Bank and at several veterinary clinics in the Lisbon area. Blood‐typing was performed by the classical agglutination assay or using a cartridge assay. Results: The study population comprised 515 DSH cats of both sexes and various ages. Frequencies of blood types A, B, and AB were 97.5%, 2.1%, and 0.4%, respectively. Conclusion: As in other parts of the world, this study showed a clear predominance of type‐A cats in the Lisbon area of Portugal.