Molecular confirmation of Trichomonas gallinae and other parabasalids from Brazil using the 5.8S and ITS-1 rRNA regions.

Clinical, gross, and histopathology lesions and molecular characterization of Trichomonas spp. infection were described in two striped owls (Asio (Rhinoptynx) clamator), one American kestrel (Falco sparverius), two green-winged saltators (Saltator similis), and in a toco toucan (Ramphastos toco) from Brazil. These birds presented clinical signs including emaciation, ruffled feathers, abundant salivation and open mouth breathing presumably due to abundant caseous material. Gross lesions were characterized by multifocal yellow friable plaques on the surface of the tongue, pharynx and/or caseous masses partially occluding the laryngeal entrance. In the owls, the caseous material extended into the mandibular muscles and invaded the sinuses of the skull. Histopathologically, marked necrotic and inflammatory lesions were associated with numerous round to oval, pale eosinophilic structures (6-10µm) with basophilic nuclei, consistent with trichomonads. Organisms similar to those described above also were found in the liver of the two green-winged saltators. To the authors' knowledge, this is the first report of trichomonosis in a striped owl and a toco toucan. Sequence analysis of the Trichomonas spp. internal transcribed spacer 1 (ITS-1) region and partial 5.8S of the ribosomal RNA (rRNA) disclosed significant genetic diversity. Two sequences had 100% identity to Trichomonas gallinae, whereas two sequences had a 99% and 92% identity to a Trichomonas vaginalis-like sequence, respectively. One sequence (green-winged saltator 502-08) had a 100% identity to a newly recognized genus Simplicomonas.

An outbreak of chlamydiosis in captive psittacines

This paper describes an outbreak of chlamydiosis psittacines recovered in Minas Gerais, Brazil, from illegal trade in the Brazilian Southeastern Region. Clinically, some birds showed apathy and anorexia or died suddenly without evidence of clinical signs. Necropsy was performed on 15 psittacines; 13 Amazon parrots (4. aestiva), one Peach-fronted parakeet (Aratinga aurea) and one Scaly-headed parrot (Pionus maximiliani). The most visible macroscopic changes were mild to marked hepatomegaly, with many white ranging in from 1 mm 100 that extended in to the parenchyma. Other findings included splenomegaly and fibrinopurulent airsacculitis. Microscopic lesions included multifocal to coalescing foci of necrosis of hepatocytes with infiltration of heterophils and lymphocytes and plasma cells randomly scattered throughout. In some parrots there were multiple foci of necrotic and granulomatous hepatitis with biliary duct proliferation. The birds with splenomegaly had loss of normal architecture and infiltration of macrophages mixed with plasma cells, fibrin and heterophils. The PVK (modified Gimenez) and Giemsa stains revealed small round intracytoplasmic bacteria approximately 1um in diameter suggestive of Chlamydophila psittaci, in the cytoplasm of macrophages of spleens and livers. Immunohistochemistry (IHC) using monoclonal antibodies for C. psitacci confirmed Chlamydophila in the cytoplasm of macrophages of the liver and spleen and in a few other organs of four parrots.

The goitrogen 6-n-propyl-2-thiouracil (PTU) given during testis development increases Sertoli and germ cell numbers per cyst in fish: the tilapia (Oreochromis niloticus) model.

The main objectives of the present study were to investigate the effects of 6-n-propyl-2-thiouracil (PTU) on Sertoli cell proliferation, germ cell number, and testis size in Nile tilapias (Oreochromis niloticus). In this regard, young fish (approximately 1 g BW and approximately 3.5 cm total in length) were treated for a period of 40 d with different concentrations (100 and 150 ppm) of PTU. The animals were killed and analyzed on d 1, 30, 40, 98, and 208 after the beginning of the treatment. On d 30 and 40 the spermatogenic process was delayed in fish treated with PTU compared with the control group. Also at these periods, treated tilapia had decreased (P < 0.05) body weight and total length. On d 98 body weight and total length had recovered in PTU-treated fish and were similar (P > 0.05) to those of the controls. However, testis weight and gonadosomatic index (testis mass/body weight) were approximately 100% higher (P < 0.05) in treated tilapia. Similarly, the area occupied by seminiferous tubules, the number of Sertoli cells and germ cells per cyst, and the number of Leydig cells per testis were significantly (P < 0.05) greater in treated fish. Nevertheless, nuclear volume and individual Leydig cell volume were significantly lower (P < 0.05) in tilapia receiving PTU treatment. Compared with controls, at 208 d all parameters analyzed presented the same trend as that observed at 98 d. In general, at 98 d the different PTU concentrations used during the treatment period induced similar effects. However, at 208 d the mean values observed for several parameters were significantly higher (P < 0.05) in fish exposed to 150 ppm. Probably due to the higher density of Sertoli cells per cyst in treated tilapia, these cells presented a smaller (P < 0.05) nucleolus and a trend to decrease its support capacity (efficiency). However, the meiotic index (germ cell loss during the two meiotic divisions) was similar (P > 0.05) in the three groups of fish investigated. Remarkably, the results found in tilapia were similar to those found for rats treated with PTU. This suggests strongly that the mechanisms of control of Sertoli cell and Leydig cell proliferation seem to be preserved during vertebrate evolution.