This study was conducted to determine the distribution patterns and duration of stay of Toxocara cati larvae in organs of chickens and to investigate chronic phase and potential zoonotic risk of toxocariasis in chickens. Chickens were orally infected with 1,000 embryonated T. cati eggs and necropsied 240 days post-infection. Organs of the chickens were examined at gross and microscopic levels; tissues were digested to recover larvae. Peribronchiolitis with infiltration of lymphocytes, and hyperplasia of bronchiolar associated lymphatic tissues (BALT) and goblet cells, were evident in the lungs of infected chickens. There were mild hemorrhages and infiltration of lymphocytes and a few eosinophils in the meninges. Larvae were recovered from 30% of the exposed chickens. Larvae recovery indicated that T. cati larvae stay alive for at least 240 days in the chicken brain. Therefore, chickens may potentially act as a paratenic host in nature and transfer T. cati larvae to other hosts.
Animals ; Brain/pathology ; Chickens ; Larva/physiology ; *Longevity ; Lung/pathology ; Poultry Diseases/*parasitology/*pathology ; Toxascariasis/pathology/*veterinary ; Toxocara/*pathogenicity/*physiology

Cochlosoma sp. infection was identified in a single case among 60 stunted diarrheic native turkey poults, Meleagris galopavo. A large number of the flagellated parasites was found free or within the intervillous spaces of the jejunum, ileum and cecum. Moderate enteritis was associated with the parasites. In TEM studies of the parasagittal sections of the parasite, a prominent ventral sucker like disc and flagella emerging from an opening on the ventrodorsal surface of the pyriform uninuclear parasite were found. The morphological characteristics of this protozoan match with those described for Cochlosoma anatis. The parasite could be considered as an intestinal pathogenic protozoan causing stunting and diarrhea in turkeys in Iran.
Animals ; Cecum/parasitology/pathology ; Enteritis/diagnosis/parasitology/veterinary ; Ileum/parasitology/pathology ; Iran ; Jejunum/parasitology/pathology ; Organelles/ultrastructure ; Poultry Diseases/*diagnosis/*parasitology ; Protozoan Infections, Animal/*diagnosis/*parasitology ; Trichomonadida/cytology/*isolation & purification ; Turkeys

Toxoplasma gondii is a protozoan parasite with a broad range of intermediate hosts. Chickens as important food-producing animals can also serve as intermediate hosts. To date, experimental studies on the pathogenicity of T. gondii in broiler chickens were rarely reported. The objective of the present study was to compare the pathogenicity of 5 different T. gondii strains (RH, CN, JS, CAT2, and CAT3) from various host species origin in 10-day-old chickens. Each group of chickens was infected intraperitoneally with 5 x 10(8), 1 x 10(8), 1 x 10(7), and 1 x 10(6) tachyzoites of the 5 strains, respectively. The negative control group was mockly inoculated with PBS alone. After infection, clinical symptoms and rectal temperatures of all the chickens were checked daily. Dead chickens during acute phage of the infection were checked for T. gondii tachyzoites by microscope, while living cases were checked for T. gondii infection at day 53 post-inoculation (PI) by PCR method. Histopathological sections were used to observe the pathological changes in the dead chickens and the living animals at day 53 PI. No significant differences were found in survival periods, histopathological findings, and clinical symptoms among the chickens infected with the RH, CN, CAT2, and CAT3 strains. Histopathological findings and clinical symptoms of the JS (chicken origin) group were similar to the others. However, average survival times of infected chickens of the JS group inoculated with 5 x 10(8) and 1 x 10(8) tachyzoites were 30.0 and 188.4 hr, respectively, significantly shorter than those of the other 4 mammalian isolates. Chickens exposed to 10(8) of T. gondii tachyzoites and higher showed acute signs of toxoplasmosis, and the lesions were relatively more severe than those exposed to lower doses. The results indicated that the pathogenicity of JS strain was comparatively stronger to the chicken, and the pathogenicity was dose-dependent.
Animals ; Antibodies, Protozoan/blood ; Cat Diseases/parasitology ; Cats ; Chickens ; Poultry Diseases/blood/mortality/*parasitology/pathology ; Swine ; Swine Diseases/parasitology ; Toxoplasma/genetics/growth & development/*pathogenicity/physiology ; Toxoplasmosis, Animal/blood/mortality/*parasitology/pathology ; Virulence

The present study was undertaken to determine the viability and infectivity of oocysts of Cryptosporidium baileyi that had been stored from 1 to 40 months at 4 degrees C preserved in 2.5% potassium dichromate solution. Oocysts of C. baileyi were purified from the feces of experimentally infected chickens using discontinuous sucrose gradients. Subsequently, the purified oocysts were suspended in 2.5% potassium dichromate solution at a concentration of 1 x 10 (7) organism/ml, and their viabilities were assessed by nucleic acid staining, histologic examination, and infectivity to 2-day-old chickens. All chickens inoculated with oocysts that had been stored for 1-18 months developed patent infections, while chickens infected with older oocysts remained uninfected. Between 5.8% and 82.2% of the oocysts, stored at 4 degrees C in 2.5% potassium dichromate solution, were found to be viable, as determined by nucleic acid staining. Parasite colonization in the bursa of Fabricius was detected in the microvillus border of bursal epithelium. The finding that C. baileyi oocysts remain infective to chickens for at least 18 months offers important time-saving advantages to investigators who frequently require large numbers of oocysts.
Animals ; Bursa of Fabricius/parasitology ; Chickens/*parasitology ; Coloring Agents ; Cryptosporidiosis/parasitology/pathology/*veterinary ; Cryptosporidium/drug effects/*growth & development/pathogenicity ; Feces/parasitology ; Oocysts/drug effects/*growth & development/pathogenicity ; *Organic Chemicals ; *Potassium Dichromate/pharmacology ; Poultry Diseases/parasitology/pathology ; Preservation, Biological/*methods ; Staining and Labeling