Case Studies

  • Cryptosporidium in a gerenuk

    Tissues from a 5-month-old gerenuk, also known as a giraffe gazelle, were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Canyon for evaluation. The calf had a history of loose stool in addition to an abscess from a previous surgery. The stool remained loose despite dietary changes, oral albendazole, injectable ivermectin, ceftiofur,…

  • Cryptosporidium serpentis in snakes

    An adult black tailed Cribo (Drymarchon melanurus), a snake native to Central and South America, was presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for chronic regurgitation.  Upon necropsy examination, the stomach was markedly thickened with prominent rugal folds. The remainder of the visceral organs appeared within normal limits.  Histologically, the…

  • Cushing’s disease diagnosed with low dose dexamethasone suppression test

    A 13-year-old female spayed Beagle was presented to its veterinarian for increased urination. On physical exam, the veterinarian noted a pot-bellied appearance and thinning hair coat. A minimum data base (CBC, Chemistry, and urinalysis) was performed in-house and revealed only a markedly increased ALKP activity, low lymphocyte count, and a low urine specific gravity (specific…

  • Cutaneous habronemiasis superimposed on a squamous cell carcinoma (SCC) in a horse

    Four partial biopsies of an infected hot brand skin lesion from a Quarter Horse stallion were submitted in 10% buffered formalin to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for histologic diagnosis. No clinical history was submitted. Histologically, the biopsies consisted of haired skin including epidermis, dermis, and subcutis. Two different lesions were identified…

  • Cutaneous pythiosis in a German Shepherd Dog

    The bacteriology section at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) received a skin swab for bacterial culture and susceptibility from a 1-year old, female, German Shepherd dog with a history of a non-healing wound over the caudal dorsum (Figure 1) that was suspected to have resulted from a dog bite.  Multiple organisms including Staphylococcus…

  • Cyanobacteria: no winter break

    Blue-green algae (cyanobacteria) barely take a break in warm winters. The most frequently observed blue-green algae that cause blooms in the greater Brazos Valley area are Microcystis sp., Oscillatoria sp., and Anabaena sp. These species all tend to produce microcystins, which are hepatotoxic to all species. In a recent case, clinical history noted a group of dogs playing in a pond thick with Microcystis colonies…

  • Cytauxzoon felis in a cat

    A 3-year-old domestic short-haired cat from central Texas died shortly after arrival at a veterinary clinic.  On gross necropsy, lesions were minimal; however, histologically every tissue examined demonstrated vascular occlusion with numerous intracytoplasmic schizonts within macrophages.  The schizonts were approximately 40 microns in diameter and contained numerous 1-3 micron merozoites. This cat died from infection…

  • Cytauxzoon felis infection in two cats

    An outdoor 5-year-old domestic medium hair cat from Gainesville, Texas was presented to a veterinarian for decreased appetite and thirst of one-day duration. The cat had disappeared a few days prior to examination. Freshly prepared blood smears were submitted for a hemoparasite examination at TVMDL. Examination of the blood smear from the cat revealed schizont-laden…

  • Cytoxic necrotizing factor 1 gene (CNF1) detected in E. coli isolated from a kitten lung

    A one-month-old, Ragdoll kitten was presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in College Station after passing away subsequent to hospitalization for respiratory illness.  The kitten was part of a large commercial breeding operation where multiple kittens were experiencing similar clinical signs. The gross necropsy findings indicated that the cause…

  • Demodex mites discovered in a white-tailed deer

    A haired skin specimen from a White-Tailed deer of unknown age was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for microscopic examination. The tissue was from a deer that had multiple cutaneous, firm, tan nodules. Microscopically, these tan nodules correlated with markedly dilated hair follicles that contained a large number of cross…