Follicular thyroid carcinoma in an inbred family of mongrel dogs in Trinidad & Tobago.

Thyroid tumors occur in many domestic species, but are most common in the dog, in which they are classified as follicular or medullary. During 2012-2016, we received tissue specimens or whole carcasses of 4 dogs with variable enlargement of the thyroid glands. The 2 males and 2 females were of mixed (mongrel) inbreeding, 3-4.5-y-old. All tumors had lobulated architecture forming follicular structures variably containing colloid. On immunohistochemistry of the tumors from 3 of the dogs, 2 were thyroglobulin positive, and all 3 were negative for calcitonin, confirming follicular thyroid carcinoma in 2 of the dogs. Thyroid carcinomas have not been reported previously in related mongrel dogs, to our knowledge.

The Prevalence of Gastrointestinal Parasites and Seroprevalence of Toxoplasma gondii in Captive Ocelots (Leopardus pardalis) in Trinidad, West Indies.

This study was conducted from November 2010 to June 2011 to determine the prevalence of gastrointestinal parasites and the seroprevalence of Toxoplasma gondii in captive ocelots (Leopardus pardalis) in Trinidad. Faecal samples were collected and analyzed using faecal flotation to identify helminth ova and protozoan cysts and oocysts. Serum samples from captive ocelots were screened for T. gondii using a latex agglutination test kit. Of the 19 ocelots examined, the most prevalent parasites noted were ova of ascarids, strongyles, and Capillaria spp. The serum of three of the 13 (23.1%) ocelots tested was positive for T. gondii antibodies. These ocelots are therefore a potential source of T. gondii infection to both humans and other animals. This is the first documented report of endoparasites in local captive ocelots within Trinidad and provides useful data to support further research of the captive and wild populations.

A Case Report of Disseminated Canine Histiocytic Sarcoma in Trinidad and Tobago.

Ocular histiocytic sarcomas (as a presenting part of disseminated histiocytic sarcoma) are not commonly diagnosed. A 10-year-old female intact Rottweiler presented to the School of Veterinary Medicine, Trinidad with buphthalmia and pain in the left eye. The cornea of the left eye appeared diffusely opaque with a conjunctival mucopurulent ocular discharge. A thorough ophthalmic assessment identified an intraocular proliferative tumor to which a unilateral enucleation was performed, however the animal died soon after. Post mortem examination and light microscopy revealed that the intraocular lesion with visceral macro-metastases was in fact a histiocytic sarcoma. Further to this, immune-phenotyping was performed to confirm the diagnosis of disseminated histiocytic sarcoma. This is the first time such a tumor has been diagnosed in Trinidad and Tobago.

A Multicentric T-Cell Lymphoma with a Plasmacytoid Morphology in a Dog.

An 8-year-old male (neutered) Labrador with a history of erythematous skin lesions and exercise intolerance for a prolonged period was suddenly found dead. Necropsy findings revealed an infiltrative, focally extensive mass which occupied 25% of the cardiac interventricular septum. Severe endocardiosis was also found on the bicuspid and tricuspid valves. The submandibular lymph nodes and kidneys were bilaterally enlarged, and the pre-hepatic lymph node and spleen were also enlarged. Multiple dermal pustules were present around the mouth and on the ear, and small ulcers were present on the tongue. Histopathological examination detected the presence of neoplastic lymphocytes with a plasmacytoid morphology in these tissues as well as in the tongue and skin lesions. Immunohistochemical (CD3⁺/CD18⁺) evaluation was consistent with a T-cell lymphoma, which could be classified as a peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS).

Oral Plasmacytoma in a Dog.

A 6-year-old male Pit bull mix dog presented for bleeding from the mouth persisting for five days. A clinical evaluation revealed a 2 × 3 cm soft tissue mandibular mass at the crown of the first premolar, as well as a non-regenerative anemia and hyperproteinemia. Cytologic and histopathologic evaluations of the mass were compatible with an oral plasmacytoma.