Toxoplasma gondii antibodies in exotic wild felids from Brazilian zoos.

Serum samples from 37 captive exotic felids in 12 zoos from six Brazilian states were assayed for antibodies to Toxoplasma gondii by the modified agglutination test using formalin-fixed whole tachyzoites. Titers greater than or equal to 1:20 were considered positive. Antibodies to T. gondii were found in 24 of 37 (64.9%) felids, including one European lynx (Lynx lynx), two jungle cats (Felis chaus), two servals (Leptailurus serval), two tigers (Panthera tigris), three leopards (Panthera pardus), and 14 of 27 lions (Panthera leo). This is the first serologic analysis for T. gondii infection in exotic wild felids from Brazilian zoos.     

Seroprevalence of Toxoplasma gondii in captive felids in Thailand

The prevalence of antibodies against Toxoplasma gondii was investigated by commercial latex agglutination test kit (Toxocheck-MT 'Eiken') in captive felids maintained at zoos and a wildlife breeding center in different geographic regions of Thailand. Sera from a total of 136 captive felids of 12 species was obtained between 2002 and 2004. The overall seroprevalence of T. gondii was found in 21 of 136 (15.4%) felids. The titers varied from 1:64 (eight samples) to 1:8192 (one sample). The seroprevalence in different geographic regions were from 0% in the northern area to 23% in the southern area. This study suggested a widespread exposure of captive felids to T. gondii in Thailand and this is the first report of serologic analysis for T. gondii in captive felids in Southeast Asia.     

Biologic and genetic comparison of Toxoplasma gondii isolates in free-range chickens from the northern Pará state and the southern state Rio Grande do Sul, Brazil revealed highly diverse and distinct parasite populations

The prevalence of Toxoplasma gondii in 84 free-range chickens (34 from the northern Pará state, and 50 from Rio Grande do Sul, the southern state) from Brazil, South America was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT), and found in 39 (46.4%) of 84 chickens with titers of 1:10 in one, 1:20 in two, 1:40 in four, 1:80 in seven, 1:160 in five, 1:320 in six, 1:640 in eight and > or =1:1280 in six. Hearts and brains of 45 chickens with titers of 1:20 or less were pooled and fed to two T. gondii-free cats. Hearts and brains of 39 chickens with titers of 1:10 or higher were bioassayed in mice. Feces of cats were examined for oocysts. One cat fed tissues from 31 chickens with titers of less than 1:10 from Rio Grande do Sul shed T. gondii oocysts. T. gondii was isolated by bioassay in mice from 33 chickens with MAT titers of 1:20 or higher. All infected mice from 10 isolates died of toxoplasmosis. All 34 isolates (15 from Pará, 19 from Rio Grande do Sul) were genotyped using 11 genetic markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, a new SAG2 and Apico. Eleven genotypes were revealed for Pará isolates and seven genotypes for Rio Grande do Sul. No genotype was shared between the two geographical locations. These data suggest that T. gondii isolates are highly diverse and genetically distinct between the two different regions in Brazil that are 3500 km apart.     

Genetic and biologic characteristics of Toxoplasma gondii isolates in free-range chickens from Colombia, South America

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 77 free-range chickens (Gallus domesticus) from Colombia, South America was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT), and found in 32 (44.4%) of 72 chickens with titers of 1:5 in 4, 1:10 in 3, 1:20 in 1, 1:40 in 1, 1:80 in 8, 1:160 in 8, 1:320 in 3, and 1:640 or higher in 4. Hearts and brains of 31 seropositive chickens were pooled and bioassayed in mice. Tissues from 32 (16+16) seronegative chickens were pooled and fed to two, T. gondii-free cats, and tissues from nine chickens without matching sera were fed to one T. gondii-free cat. Feces of cats were examined for oocysts. T. gondii oocysts were excreted by a cat that was fed tissues of 16 seronegative chickens. T. gondii was isolated by bioassay in mice from 23 chickens with MAT titers of 1:20 or higher. All infected mice from 16 of the 23 isolates died of toxoplasmosis. Overall, 82 (81.1%) of 101 mice that became infected after inoculation with chicken tissues died of toxoplasmosis. Genotyping of these 24 isolates using polymorphisms at the SAG2 locus indicated that seven T. gondii isolates were Type I, 17 were Type III, and none was Type II. Phenotypically, T. gondii isolates from chickens from Colombia were similar to isolates from Brazil but different from the isolates from North America; most isolates from chickens from Brazil and Colombia were lethal for mice whereas isolates from North America did not kill inoculated mice. Genetically, none of the T. gondii isolates from Colombia and Brazil was SAG2 Type II, whereas most isolates from chickens from North America were Type II. This is the first report of genetic characterization of T. gondii isolates from Colombia, South America.     

Genetic and biologic characteristics of Toxoplasma gondii infections in free-range chickens from Austria

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in free-range chickens (Gallus domesticus) from 11 Bio-farms in Austria was determined. Antibodies to T. gondii assayed by the modified agglutination test (MAT) were found in 302 of 830 (36.3%) chickens with titers of 1:10 in 50, 1:20 in 69, 1:40 in 53, 1:80 in 40, 1:160 or higher in 90. Hearts of 218 chickens with MAT titers of 10 or higher were bioassayed individually in mice. Tissues from 1183 chickens were pooled and fed to 15, T. gondii-free cats. Feces of the cats were examined for oocysts; 11 cats shed T. gondii oocysts. T. gondii was isolated from 56 chickens by bioassay in mice. Thus, there were 67 isolates of T. gondii from these chickens. Genotyping of these 67 isolates using the SAG2 locus indicated that all 33 were Type II. Phenotypically and genetically these isolates were different from T. gondii isolates from Brazil. None of the isolates was virulent for mice. This is the first report of isolation of T. gondii from chickens from Austria.     

Toxoplasma gondii infection in cats from São Paulo state, Brazil: seroprevalence, oocyst shedding, isolation in mice, and biologic and molecular characterization

Cats are the most important hosts in the epidemiology of Toxoplasma gondii infections in humans and animals. Serologic and parasitological prevalence of T. gondii were determined in 237 cats from 15 counties in S?o Paulo state, Brazil. Antibodies to T. gondii were found in a 1:25 dilution of serum of 84 (35.4%) out of 237 cats by the modified agglutination test (MAT). Samples of brain, heart, tongue, and limb muscles (total 50 g) of 71 of the seropositive cats were pooled for each cat, digested in pepsin and bioassayed in mice. Faeces (1 g) from the rectum of each cat were examined microscopically for T. gondii-like oocysts and verified by bioassay in mice; T. gondii oocysts were found in the faeces of three (1.3%) of 237 cats. T. gondii was isolated from tissue homogenates of 47 cats. The DNA obtained from these 47 tissue isolates was characterized using the SAG2 locus: 34 (72.4%) isolates were type I, 12 (25.5%) were type III and one (2.1%) was mixed with types I and III. No type II isolates were detected. Most (23/34) of the type I isolates killed all infected mice and 7 of 12 type III isolates did not kill infected mice. Characterization of the SAG2 locus directly from tissue homogenates from 37 of 46 cats was successful. Genotypes obtained from these primary samples were the same as those from the corresponding isolates obtained in mice. Genotyping of the three oocyst isolates revealed that two were type I and one was type III. Molecular and biologic characteristics of T. gondii isolates from animals from Brazil are different from those from other parts of the world.     

Characterization of Toxoplasma gondii isolates from free range chickens from Paraná, Brazil

The prevalence of Toxoplasma gondii in free range chickens is a good indicator of the prevalence of T. gondii oocysts in the environment because chickens feed from the ground. In the present study, prevalence of T. gondii in 40 free range chickens (Gallus domesticus) from a rural area surrounding Paraná, Brazil was assessed. Blood, heart, and brain from each chicken were examined for T. gondii infection. Antibodies to T. gondii, assayed with the modified agglutination test (MAT> or =1:5) were found in 16 chickens. Hearts and brains of seropositive (MAT> or =1:5) chickens were bioassayed in mice. Additionally, hearts and brains of seronegative (MAT<1:5) chickens were bioassayed in two T. gondii-free cats (12 chickens per cat). T. gondii was isolated from 13 of 16 (81%) seropositive chickens. Of the two cats fed tissues pooled form seronegative chickens, one shed T. gondii oocysts. Nine of the 13 T. gondii isolates killed 100% of infected mice. The T. gondii isolate from the cat was also virulent for mice. Genotyping of 13 chicken isolates of T. gondii using the SAG2 locus indicated that seven isolates were type I and six were type III; three of these type III isolates killed all infected mice suggesting that all strains virulent for mice are not type I. The isolate from the feces of the cat fed chicken tissues was type I.     

Isolation and molecular characterization of Toxoplasma gondii from chickens and ducks from Egypt

The prevalence of Toxoplasma gondii in free range chickens is a good indicator of the prevalence of T. gondii oocysts in the environment because chickens feed from the ground. In the present study, prevalence of T. gondii in 121 free range chickens (Gallus domesticus) and 19 ducks (Anas sp.) from a rural area surrounding Giza, Egypt was assessed. Blood, heart, and brain from each animal were examined for T. gondii infection. Antibodies to T. gondii, assayed with the modified agglutination test (MAT), were found in 49 (40.4%) chickens in titers of 1:5 in 11, 1:10 in four, 1:20 in four, 1:40 in eight, 1:80 in 10, and 1:160 or more in 12 chickens. Antibodies were found in three ducks each with a titer of 1:80. Hearts and brains of seropositive (MAT > or = 1:5) chickens and ducks were bioassayed in mice. Additionally, hearts and brains of seronegative (MAT<1:5) animals were bioassayed in T. gondii-free cats. T. gondii was isolated from 19 of 49 seropositive chickens (one with a titer of 1:5, two with a titer of 1:20, one with a titer of 1:40, five with a titer of 1:80, three with a titer of 1:160, and seven with a titer of > or = 1:360). One cat fed tissues pooled from 15 seronegative chickens shed T. gondii oocysts, while two cats fed tissues of 34 seronegative chickens did not shed oocysts. T. gondii was isolated from one of the seropositive ducks by bioassay in mice. The two cats fed tissues from 16 seronegative ducks did not shed oocysts. Genotyping of 20 chicken isolates of T. gondii using the SAG 2 locus indicated that 17 isolates were type III and three were type II. The duck isolate of T. gondii was type III. The mice inoculated with tissue stages of all 21 isolates of T. gondii from chickens and ducks remained asymptomatic, indicating that phenotypically they were not type I because type I strains are lethal for mice. Infections with mixed genotypes were not found.     

Seroprevalence of Toxoplasma gondii in American free-ranging or captive pumas (Felis concolor) and bobcats (Lynx rufus)

Toxoplasma gondii is a major zoonotic agent infecting a wide range of mammals, including wild felids. Like domestic cats, wild felids are involved in the complete infective cycle of T. gondii, as they can host in their gastrointestinal tract sexually mature parasites and shed infective oocysts in their feces. In order to evaluate the importance of this wildlife reservoir, 438 serum samples collected between 1984 and 1999 from 438 pumas (Felis concolor) and from 58 bobcats (Lynx rufus) from North America, Central America and South America were screened for antibodies to T. gondii. The overall prevalence of T. gondii antibodies was 22.4% in pumas and 51.7% in bobcats, with regional variations. Adults were more likely to be seropositive than juveniles and kittens (prevalence ratio (PR) = 2.61; confidence interval (CI) = 1.15, 4.04). In the US, pumas from the southwestern states (Arizona, California and New Mexico) were more likely to be seropositive for T. gondii ( PR = 2.61; 95% CI = 1.32-5.18 ) than pumas from the northwestern and mountain states (Colorado, Idaho, Oregon, Utah and Wyoming). Male pumas from the US were more likely to be seropositive than females (PR = 2.08; 95% CI = 1.11-3.92), whereas female pumas from Mexico, Central America and South America were more likely to be seropositive than female pumas from Canada and the US (PR = 2.49; 95% CI = 1.09-5.69). Captive pumas were also more likely to be seropositive (21.7%, 29/92) for T. gondii than free-ranging animals (19.9%, 69/346) (PR = 1.85; 95% CI = 1.06, 3.17).     

Genetic and biologic characterization of Toxoplasma gondii isolates of cats from China

Cats are important in the epidemiology of Toxoplasma gondii infection because they are the only hosts that can excrete the environmentally resistant oocysts. In the present study, prevalence of T. gondii was determined in serum, feces, and tissues of 34 cats from People's Republic of China. Antibodies to T. gondii were assayed by the modified agglutination test and found in 27 of 34 (79.4%) cats with titers of 1:40 in one, 1:80 in one, 1:160 in three, 1:320 in three, 1:640 in eight, and 1:1280 or higher in 11 cats. T. gondii oocysts were not found in feces of any cat as ascertained by bioassay in mice. Tissues (brain, heart, and tongue) of 27 seropositive cats were pooled and bioassayed in mice (8 cats) or cats (19 cats). T. gondii was isolated from tissues of 17 of 27 seropositive cats. Genotyping of these 17 T. gondii isolates using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and a new SAG2, and an apicoplast marker Apico revealed two genotypes. This is the first report of genetic typing of T. gondii isolates from cats from China.     

Seroprevalence of Neospora caninum in free-range chickens (Gallus domesticus) from the Americas

Neospora caninum and Toxoplasma gondii are biologically and morphologically similar coccidians with canids as definitive hosts for N. caninum and felids for T. gondii. Feral chickens have been used as indicators of soil contamination with T. gondii oocysts because they feed from ground. In the present study we studied seroprevalence of N. caninum in free range chickens from different countries in America as an indicator of soil contamination due to N. caninum oocysts. Antibodies to N. caninum were found in sera of 524 (39.5%) of 1324 chickens using indirect fluorescent antibody test (IFAT, titer 1:25 or higher). Seropositive chickens from different countries were: 18.5% of 97 from Mexico, 7.2% of 97 from USA, 39.5% of 144 from Costa Rica, 71.5% of 102 from Grenada, 44% of 50 from Guatemala, 83.6% of 98 from Nicaragua, 58.1% of 55 from Argentina, 34.3% of 358 from Brazil, 62.3% of 85 from Chile, 11.2% of 62 from Colombia, 38.7% of 80 from Guyana, 18% of 50 from Peru and 21.7% of 46 from Venezuela. The results indicate widespread exposure of chickens to N. caninum.     

Prevalence of Toxoplasma gondii in dogs from Colombia, South America and genetic characterization of T. gondii isolates

The prevalence of Toxoplasma gondii in 309 unwanted dogs from Bogotá, Colombia, South America was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 52 (16.8%) of 309 dogs with titers of 1:20 in 20, 1:40 in six, 1:80 in 17, 1:160 in three, 1:320 in three, 1:1280 or higher in three. Some organs obtained after necropsy of dogs (hearts, tongues and brains, either separately or pooled) were used in bioassays carried out in mice (37 samples, of which 20 were assayed with separate organs and 17 were assayed with pooled organs), cats (pooled organs from six) and pooled organs of two dogs both in mice and cat. Mice receiving dog tissues were examined for T. gondii infection. Feces of cats that received dog tissues were examined for oocyst shedding. In total, T. gondii was isolated from tissues of 20 dogs (16 by bioassays in mice, 3 by bioassay in cats and 1 by bioassay in mice and cat). All infected mice from 7 of 17 isolates bioassayed in this host died of toxoplasmosis during primary infection. Only 10 of the 20 dogs whose tissues were bioassayed separately induced infections in mice. Interestingly, dog organs varied in their capacity to induce T. gondii infection in mice, hearts and tongues producing more positive results than the brain. The 20 T. gondii isolates obtained from seropositive dogs were PCR-RFLP genotyped using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, a new SAG2 and an apicoplast marker Apico. Ten genotypes were revealed. These genotypes are different from the three predominant Types I, II and III lineages that are widely spread in North America and Europe. A new allele denoted u-3 at PK1 locus was identified in three isolates. This result supports previous findings that T. gondii population is highly diverse in Colombia.     

Genetic characterization of Toxoplasma gondii isolates in dogs from Vietnam suggests their South American origin

Dogs are considered a potential risk for transmission of Toxoplasma gondii to humans because they can mechanically transmit oocysts to people and in certain parts of the world dog meat is consumed by humans. The prevalence of T. gondii in 42 dogs from rural Vietnam was determined. Antibodies to T. gondii were assayed by the modified agglutination test, and found in 21 (50%) of 42 dogs with titers of 1:20 in six, 1:40 in seven, 1:80 in two, 1:160 in two, 1:320 in two, 1:640 in one, and 1:1280 or higher in one. Hearts, tongues and brains of 21 seropositive dogs were bioassayed in cats, mice or both. Tissues from eight seropositive dogs were fed to eight T. gondii-free cats. Feces of cats were examined for oocysts. T. gondii was isolated from eight dogs by bioassay in cats. Genotyping of these eight T. gondii isolates using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and a new SAG2, and an apicoplast marker Apico revealed two genotypes. Both genotypes were previously identified from the dog isolates in Colombia, suggesting their South America origin. However, they are different from the predominant Type I, II and III lineages that are widely spread in North America and Europe. This is the first report of isolation of viable T. gondii from any host in Vietnam.     

High prevalence of Toxoplasma gondii in a commercial flock of chickens in Israel, and public health implications of free-range farming

Little is known of the prevalence of Toxoplasma gondii in commercially raised chickens. In the present study, the prevalence of T. gondii in 96 free-range chickens (Gallus domesticus) from a commercial farm in Israel was assessed. Blood, heart, and brain from each chicken were examined for T. gondii infection. Antibodies to T. gondii, assayed with the modified agglutination test (MAT > or = 1:5), were found in 45 of the 96 chickens. Hearts and brains of seropositive (MAT > or = 1:5) chickens were bioassayed in mice. Additionally, hearts and brains of 51 seronegative (MAT < 1:5) chickens were bioassayed in two T. gondii-free cats. T. gondii was isolated from 19 of the 45 (42.2%) seropositive chickens by bioassay in mice. Both the cats fed tissues pooled from seronegative chickens shed T. gondii oocysts. Tachyzoites and tissue cysts of all 21 isolates of T. gondii from chickens were avirulent for mice. Seventeen of the 19 isolates genotyped were found to be type II, and 2 were type III. Understanding of the sources of infection on such farms could be the key to the development of better prevention strategies.     

Prevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in ovine from São Paulo State, Brazil

Serum samples from 597 sheep from S?o Paulo State, in the southeastern region of Brazil, were tested to determine the prevalence of antibodies directed against Toxoplasma gondii (> or = 1:64) and Neospora caninum (> or = 1:50) using the indirect fluorescent antibody test (IFAT). The animals were divided into three groups based on their age: < or = 1 year, 1-4 years, and > or = 4 years. Antibodies to T. gondii were observed in 34.7% of the samples with titers ranging from 64 to 16,384 and IgG antibodies directed against N. caninum were observed in 9.2%, with titers ranging from 50 to 3200. Only 3.5% of the sheep were positive for both agents. All farms had at least one positive animal for T. gondii, and 26 of the 30 farms had at least one positive animal for N. caninum. An association between seroprevalence and age was observed for T. gondii (P = 0.001), but not to N. caninum (P = 0.343). It was not possible to associate seroprevalence to T. gondii and the presence of domestic or feral cats, since in all farms there was at least one positive sheep. There was no association between seropositivity to N. caninum and the presence of domestic (P = 1.000) and feral dogs (P = 0.550).     

Seroprevalence of Toxoplasma gondii antibodies in wild carnivores from Spain

Serum samples from 282 wild carnivores from different regions of Spain were tested for antibodies to Toxoplasma gondii by the modified agglutination test using a cut-off value of 1:25. Antibodies to T. gondii were found in 22 of 27 (81.5%) of Iberian lynx (Lynx pardinus), 3 of 6 European wildcats (Felis silvestris), 66 of 102 (64.7%) red foxes (Vulpes vulpes), 15 of 32 (46.9%) wolves (Canis lupus), 26 of 37 (70.3%) Eurasian badgers (Meles meles), 17 of 20 (85.0%) stone martens (Martes foina), 4 of 4 pine martens (Martes martes), 6 of 6 Eurasian otters (Lutra lutra), 4 of 4 polecats (Mustela putorius), 1 of 1 ferret (Mustela putorius furo), 13 of 21 (61.9%) European genets (Genetta genetta), and 13 of 22 (59.1%) Egyptian mongooses (Herpestes ichneumon). Serological results indicated a widespread exposure to T. gondii among wild carnivores in Spain. The high T. gondii seroprevalence in Iberian lynx and the European wildcat reported here may be of epidemiologic significance because seropositive cats might have shed oocysts.     

Isolation and genetic characterisation of Toxoplasma gondii from a red-handed howler monkey (Alouatta belzebul), a jaguarundi (Puma yagouaroundi), and a black-eared opossum (Didelphis aurita) from Brazil

Toxoplasma gondii isolates are highly diverse in domestic animals from Brazil. However, little is known about the genetics of this parasite from wild mammals in the same region. Reveal genetic similarity or difference of T. gondii among different animal populations is necessary for us to understand transmission of this parasite. Here we reported isolation and genetic characterisation of three T. gondii isolates from wild animals in Brazil. The parasite was isolated by bioassay in mice from tissues of a young male red handed howler monkey (Alouatta belzebul), an adult male jaguarundi (Puma yagouaroundi), and an adult female black-eared opossum (Didelphis aurita). The monkey and the jaguarundi had inhabited the Zoo of Parque Estadual Dois Irm?os, Pernambuco State, Northeastern Brazil, for 1 year and 8 years, respectively. The wild black-eared opossum was captured in S?o Paulo State, Southeastern Brazil, and euthanised for this study because it was seropositive for T. gondii (titre 1:100 by the modified agglutination test, MAT). Ten PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) markers, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico, were used to genotype the isolates. T. gondii was isolated from the brain and heart homogenate of the monkey, the muscle homogenate of the jaguarundi, and the heart homogenate of the black-eared opossum. This was the first isolation of T. gondii from a neotropical felid from Brazil. The isolate from the monkey (TgRhHmBr1) was not virulent in mice, whereas the isolates from the jaguarundi (TgJagBr1) and the black-eared opossum (TgOpBr1) were virulent in mice. The genotype of the isolate from the monkey has been identified in isolates from a goat and ten chickens in the same region of Brazil, suggesting that it may be a common lineage circulating in this region. The genotypes of the isolates from the jaguarundi and the black-eared opossum have not been previously reported. Although there are already 88 genotypes identified from a variety of animal hosts in Brazil, new genotypes are continuously being identified from different animal species, indicating an extremely high diversity of T. gondii in the population.     

Genotyping of Toxoplasma gondii isolates from chickens from India

The present study was undertaken to isolate and genotype Toxoplasma gondii from free-range chickens (Gallus domesticus) from villages in Maharashtra and Tamil Nadu states of central and south India, respectively. Blood, heart, and brain from a total of 741 chickens were examined for T. gondii infection. Antibodies to T. gondii, as assayed with the modified agglutination test (MAT >or = 1:5) were found in 133 (17.9%) chickens. Hearts and brains of 186 chickens were bioassayed in mice. Additionally, hearts and/or brains of most of the seronegative (MAT < 1:5) chickens were fed to 20 T. gondii-free cats, while 32 seropositive chickens (MAT 1:5) were fed to 3 cats. T. gondii was not isolated from any of the chickens by mouse bioassay. Five of the cats that were fed seronegative chickens shed oocysts, while isolates were not obtained from any of the other cats fed seropositive chickens. These five isolates, along with the two that were previously isolated in India through cat bioassay, were genetically analyzed. Genotyping using the SAG 2 locus indicated that two isolates were type II and five were type III. Microsatellite analysis revealed allelic differences between and within the lineages. This is the first report of genetic characterization of any T. gondii isolate from India.     

Seroprevalences of Neospora caninum and Toxoplasma gondii in nondomestic felids from southern Africa.

Sera from 68 nondomestic captive and free-ranging felids from southern Africa were tested for antibodies to Neospora caninum and Toxoplasma gondii by the indirect fluorescent antibody test. Four of the 68 (5.9%) serum samples were positive for antibodies to N. caninum, with titers ranging from 1:50 to 1:200. All other animals were negative for antibodies to N. caninum at a dilution of 1:50. Fifty of the 68 (74%) serum samples tested positive for antibodies to T. gondii, with titers ranging from 1:50 to 1:26,500. Four animals tested positive for antibodies to both N. caninum and T. gondii. None of these animals displayed clinical signs of disease. Results of this study indicate that nondomestic felids in southern Africa have been exposed to, and are likely infected with, N. caninum and T. gondii.     

Biologic and genetic characteristics of Toxoplasma gondii isolates in free-range chickens from Costa Rica, Central America

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 144 free-range chickens (Gallus domesticus) from Costa Rica was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT), and found in 60 (40.1%) of 144 chickens with titers of 1:5 in 16, 1:10 in 5, 1:20 in 2, 1:40 in 3, 1:80 in 5, and 1:160 or higher in 29. Tissues of all chickens were bioassayed for T. gondii in mice or cats. Hearts and brains of 52 chickens with titers of 1:5 or higher and 16 chickens with doubtful titers were pooled and bioassayed in mice. Tissues from 76 chickens with MAT titers of 1:10 or less were pooled and fed to three T. gondii-free cats. Fecal floats of cats were bioassayed orally in mice but were negative for T. gondii oocysts. T. gondii was isolated by bioassay in mice from 32 chickens with MAT titers of 1:10 or higher. All infected mice from 4 of the 32 isolates died of toxoplasmosis. Genotyping of these 32 isolates using polymorphisms at the loci SAG1, SAG2, SAG3, BTUB and GRA6 revealed five genotypes. Five isolates had type I alleles and one isolate had type III alleles at all loci. The rest 26 isolates contained the combination of type I and II or I and III alleles and were divided into three genotypes. None was found to have genotype II alleles at all five loci. This is the first report of genetic characterization of T. gondii isolates from Costa Rica, Central America.