Pituitary adenoma with galactorrhea in an adult male cynomolgus macaque (Macaca fascicularis)

Although endocrinopathies in many animal species are well documented, an adult, male, wild-caught cynomolgus macaque (Macaca fascicularis) presented an interesting diagnostic challenge. Previous physical examinations had been unremarkable with the exception of a heart murmur. The animal presented with ulcerative dermatitis in the dorsal cervical area, and physical exam revealed white material around the nipples. A white milky substance could be expressed bilaterally from the nipples. Hematologic, serologic, and urine samples revealed glucosuria, ketonuria, and hyperglycemia. Further diagnostic testing confirmed persistent hyperglycemia and revealed elevated serum prolactin and cortisol levels. During subsequent imaging studies, the animal underwent cardiac arrest and was euthanized. Gross necropsy findings included an enlarged pituitary gland. A prolactin-secreting pituitary adenoma was confirmed on histopathology. In light of the results of serum biochemical analyses, the additional diagnosis of type II non-insulin-dependent diabetes mellitus was made. This case represents the first documented antemortem diagnosis of a prolactin-secreting pituitary tumor in a cynomolgus macaque.

Comparison of two heavy metal chelators for treatment of lead toxicosis in cockatiels

OBJECTIVE

To compare efficacy and safety of meso-2,3-dimercaptosuccinic acid (DMSA) and Ca EDTA for treatment of experimentally induced lead toxicosis in cockatiels (Nymphicus hollandicus).

ANIMALS

137 (69 females, 68 males) healthy cockatiels between 6 months and 8 years old.

PROCEDURE

Lead toxicosis was induced by placing lead shot in the gastrointestinal tract. Treatment with Ca EDTA (40 mg/kg of body weight, IM, q 12 h), DMSA (40 or 80 mg/kg, PO, q 12 h), and sodium sulfate salts (SSS; 0.5 mg/kg, PO, q 48 h) was initiated 4 days after induction of lead toxicosis. Blood lead concentrations were determined, using atomic absorption spectrophotometry. Number of birds surviving and blood lead concentrations were compared among groups.

RESULTS

In Phase II of the study, administration of DMSA and Ca EDTA significantly decreased blood lead concentrations when used alone or in combination in birds with lead toxicosis. Addition of SSS did not result in further decreases in lead concentrations. Eight of 12 (66.7%) birds without lead toxicosis given 80 mg of DMSA/kg did not survive to the end of the study. Lesions related to treatment with chelating agents were not detected during necropsy.

CONCLUSIONS AND CLINICAL RELEVANCE

DMSA and Ca EDTA are effective chelating agents in cockatiels. Because DMSA is administered orally, it may be easier than other chelating agents for bird owners to administer at home. However, the narrow margin of safety of DMSA indicates that this agent should be used with caution.

Detection of Sarcocystis neurona in the brain of a Grant's zebra (Equus burchelli bohmi)

An 8-yr-old intact male Grant's zebra (Equus burchelli bohmi) was referred to the Veterinary Medical Teaching Hospital of the University of California-Davis after being found in the owner's pasture obtunded and in lateral recumbency. The animal was hypothermic, weak, and unwilling to rise. There was no evidence of trauma, and the zebra had seemed normal the preceding evening. There was no extensor rigidity, and cranial nerve reflexes were normal. Flexor and extensor reflexes were weak upon initial examination. A complete blood count and serum biochemistry analysis revealed a mild leukocytosis, hyperfibrinogenemia, hypoglycemia, hyponatremia, hypochloremia, hypocalcemia, and hypoalbuminemia. Urinalysis was normal, and a urine toxicology screen for alkaloids was negative. No toxic substance was found in the hay or pasture grasses although the owner reported the presence of yellow star thistle and mushrooms in the pasture. The cerebrospinal fluid cytologic and biochemical analyses were normal, but antibodies to Sarcocystis neurona were detected. The zebra died despite aggressive supportive therapy over a 4-day period. The necropsy demonstrated severe gastrointestinal nematodiasis that could account for hypoalbuminemia and electrolyte abnormalities. Histopathologic examination of the nervous system revealed focal areas of perivascular cuffing in the brainstem that were comprised mainly of lymphocytes, monocytes, and plasma cells. Immunohistochemical staining identified the presence of S. neurona merozoites associated with the lesions. This zebra probably died from severe endoparasitism that resulted in malabsorption, weakness, and recumbency rather than from encephalitis associated with S. neurona merozoites. Equine protozoal myeloencephalitis has not been reported previously in nondomestic equids.

An experimental soft-release of oil-spill rehabilitated American coots (Fulica americana): II. Effects on health and blood parameters

The Unocal-Metrolink oil spill of 21 February 1995 resulted in approximately 7800 barrels of San Joaquin crude oil being deposited into the San Gabriel River in Huntington Beach, CA, USA. In order to determine long-term pathological effects of oil exposure and rehabilitation, hematological and serum biochemical parameters for both rehabilitated (RHB) American coots (Fulica americana) and reference (REF) coots were examined every 3-4 weeks (56, 81, 108 and 140 days post oil exposure) after birds were cleaned, rehabilitated and soft-released. Most significant differences in monthly comparisons between RHB and REF birds occurred 56 days following oil exposure. Total white blood cell (WBC) count, albumin:globulin (A:G) ratio and calcium concentration were higher in RHB birds compared to REF birds 56 days post oil exposure. In addition, mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase and creatine kinase activities, and creatinine, total protein (TP) and globulin concentrations were lower in RHB birds. Blood results from 56 days post oil exposure for RHB coots which subsequently died were compared to blood results from days 108 and 140 for REF coots which survived. Oiled and rehabilitated birds which died had significantly higher WBCs, packed cell volume, TP and globulin concentrations, and lower A:G ratio, MCH, MCHC, glucose and sodium concentrations compared to REF birds which survived. Blood result differences detected at 3-4-week intervals between RHB and REF survivors, and differences detected between RHB coots which died and REF coots which survived, suggested that RHB coots developed an inflammatory response (infectious or non-septic) and, concurrently, may have experienced decreased immune responsiveness. Additionally, RHB coots experienced either an iron (Fe) utilization or Fe metabolism problem. These pathophysiological mechanisms were consistent with increased hemosiderin (stored Fe) present in the liver, spleen and kidney of necropsied RHB birds, and may have contributed to RHB coot mortality. When blood parameter differences were examined for their impact on survival time, it was determined that RHB coots had shorter survival times if they had very high cholesterol (> or =449 mg/dl) or chloride (> or =110 MEQ/l) concentrations on day 56 post oil exposure. Interestingly, the lack of differences between RHB and REF coots from day 81 through day 140 suggested that, from a hematologic and clinical chemistry perspective, coots which were oiled, rehabilitated, released and survived at least 3.5 months could not be differentiated from wild (REF) coots. From these findings it appears that blood analysis, coupled with post-release survival data, may help discern reasons for increased mortality of oiled and rehabilitated birds, compared to non-oiled reference birds.

Congenital defects in northern elephant seals stranded along the central California coast

Eleven cases of congenital anomalies were identified in 210 (5%) juvenile northern elephant seals (Mirounga angustirostris) found stranded along the central California (USA) coast from 1 January 1988 to 31 December 1995. Seven individuals had mild-to-moderate hydrocephalus involving the lateral ventricles bilaterally, or the lateral and third ventricles. Two animals had severe cardiac anomalies: hypoplasia of the right ventricle with overriding aorta, and ventricular septal defect. Other anomalies included single cases of hydronephrosis, focal pulmonary dysplasia, and congenital epidermal angiomatosis. Common intercurrent disease processes were verminous pneumonia and arteritis, verminous enteritis and coliti, and splenic and hepatic hemosiderosis. The more severe anomalies were considered to be the cause of debilitation and stranding. Milder anomalies were found incidentally during routine gross necropsy and histopathologic examination.

Coccidioidomycosis in free-living California sea lions (Zalophus californianus) in central California

Coccidioidomycosis is described in seven California sea lions (Zalophus californianus) admitted to The Marine Mammal Center, Sausalito, California (USA), between January 1986 and December 1994. Diagnoses were confirmed by histology in all seven cases, culture in three cases, and serology in one case. These are believed to be the first published cases of coccidioidomycosis in free-ranging California sea lions.

Metastatic carcinoma of probable transitional cell origin in 66 free-living California sea lions (Zalophus californianus), 1979 to 1994

Sixty-six (18%) cases of widely metastatic carcinoma of probable transitional cell origin were identified in 370 California sea lions (Zalophus californianus) stranded alive along the central California (USA) coast, between January 1979 and December 1994. Live animals were usually emaciated and anorectic, with perineal edema and occasionally hind-flipper paralysis or paresis. Large yellow caseous masses were observed in the sub-lumbar lymph nodes, often extending around the ureters resulting in hydroureter. Histologically, metastases were usually widespread, and the primary neoplastic focus undetectable. This is the highest reported prevalence among necropsied animals of neoplasia in a pinniped population to date.