AGE-RELATED CHANGES IN HEMATOLOGY AND BLOOD BIOCHEMISTRY VALUES IN ENDANGERED, WILD RING-TAILED LEMURS ( LEMUR CATTA) AT THE BEZÀ MAHAFALY SPECIAL RESERVE, MADAGASCAR.

The health of 44 wild ring-tailed lemurs ( Lemur catta) at the Bezà Mahafaly Special Reserve was assessed across three age classes: <5 yr (young), 5-9 yr (adult), and ≥10 yr (old). Hematology and biochemistry tests were performed manually (leukocyte count and differential, packed cell volume, total protein) and using a point-of-care analyzer (hematocrit, hemoglobin, glucose, blood urea nitrogen, creatinine, sodium, potassium, chloride, ionized calcium, total carbon dioxide, anion gap), respectively. Urine specific gravity was measured via refractometry. Age- and sex-related differences were detected. Old lemurs had significantly lower lymphocyte count than adult and young lemurs, leading to markedly lower total leukocyte count and higher neutrophil-to-lymphocyte ratio. Decreased lymphocyte count with advanced age is consistent with immunosenescence. Young lemurs had significantly higher total protein, monocyte count, and potassium than adult and old lemurs but significantly lower ionized calcium than adult lemurs. Males had significantly higher leukocyte, neutrophil, and monocyte counts; lower percentage basophils; and higher blood urea nitrogen than females. Females had markedly higher glucose than males. Young females had the highest monocyte count and total protein, which were significantly lower in the adult and old age classes. Basophil count was stable in females across age but dropped precipitously in males in the adult and old age classes. Within adult and old age classes, males had significantly higher blood urea nitrogen and lower basophils than females. Glucose was significantly higher after α2 agonist administration. Identifying age-related hematologic and biochemical changes in apparently healthy wild ring-tailed lemurs will aid in clinical diagnosis and treatment of lemurs in human care, which is especially relevant for management of geriatric animals in zoo populations. Equally important, a better understanding of the ability of aging lemurs to tolerate environmental stressors will inform the capacity for this species to cope with ongoing and future habitat alteration.

Ring-Tailed Lemur (Lemur catta) Health Parameters across Two Habitats with Varied Levels of Human Disturbance at the Bezà Mahafaly Special Reserve, Madagascar.

The health of 36 wild, free-ranging ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve was assessed across 2 habitats of varied human impact: a reserve riverine gallery forest, and a degraded mixed dry deciduous and Alluaudia-dominated spiny forest. While there were no statistically significant differences in leukocyte count or differential between habitats, female lemurs in the reserve gallery forest had significantly higher percentages of monocytes and eosinophils than male lemurs in the gallery forest. Lemurs from the degraded spiny habitat had significantly higher mean packed cell volume, hematocrit, hemoglobin, total protein, blood urea nitrogen, chloride, ionized calcium and urine specific gravity than lemurs from the reserve gallery forest. These findings may reflect lower hydration levels in lemurs living in degraded habitat, providing evidence that environmental degradation has identifiable impacts on the physiology and health of wild, free-ranging ring-tailed lemurs living in nearby habitats. Given the greater evidence of human impact in the mixed dry deciduous/spiny forest habitat, a pattern seen throughout southern Madagascar, biomedical markers suggestive of decreased hydration can provide empirical data to inform new conservation policies facilitating the long-term survival of this lemur community.

Successful treatment of a southern Pacific rattlesnake (Crotalus viridis helleri) bite in a caracal (Caracal caracal).

A caracal (Caracal caracal) was bitten on the lower lip by a southern Pacific rattlesnake (Crotalus viridis helleri) and quickly developed progressive, severe soft tissue swelling and bruising of this site. Initial laboratory results revealed prolonged clotting times within the first hour of envenomation, followed by signs of vasculitis and anemia. The caracal was successfully treated with intravenous crystalloids, four vials of polyvalent crotalidae antivenom, and transfusions of bovine hemoglobin glutamer-200 (Oxyglobin) and fresh whole blood. The progressive soft tissue swelling and bruising halted and the coagulation parameters improved after administration of antivenom; however, the caracal continued to show neurologic dysfunction, including depression, weakness, muscle fasciculations, anisocoria, and ataxia. Administration of an additional vial of antivenom 72 hr after envenomation quickly corrected the weakness and muscle fasciculations, whereas the anisocoria and mild ataxia persisted for another 24 hr. The caracal remains clinically normal 3 yr after the envenomation.

Diagnosis and treatment of chronic T-lymphocytic leukemia in a spotted hyena (Crocuta crocuta).

Physical examination of an asymptomatic 20-yr-old intact female spotted hyena (Crocuta crocuta) revealed a midabdominal mass. A complete blood count (CBC) revealed peripheral lymphocytosis. Abdominal ultrasonography and laparoscopy confirmed severe splenomegaly. Cytologic examination of a bone-marrow core and histologic examination of spleen and liver biopsy samples revealed neoplastic small lymphocytes. Immunohistochemical staining of liver and spleen samples with the use of leukocyte-specific monoclonal antibodies showed that the neoplastic lymphocytes were immunoreactive to T-lymphocyte CD3 receptor and immunonegative to B-lymphocyte CD79a receptor. The morphology and distribution of neoplastic T-lymphocytes within the spleen, liver, peripheral blood, and bone marrow was most consistent with chronic T-lymphocytic leukemia. Treatment with chlorambucil and prednisone effectively decreased the lymphocyte count, but was associated with thrombocytopenia, which resolved after chlorambucil treatment was temporarily discontinued. Chemotherapy was resumed with a single dose of L-asparaginase, followed by a lower dosage of chlorambucil and continued prednisone. Two years after initial diagnosis, the hyena developed a hemoabdomen and was euthanized. Neoplastic T-lymphocytes were present in spleen, liver, visceral and peripheral lymph nodes, lungs, heart, kidney, adrenal glands, mesentery, intestines, pancreas, brain, and bone marrow.