PROSPECTIVE POSTMORTEM ASSESSMENT OF THE INCIDENCE OF MAMMARY NEOPLASIA IN CHIMPANZEES (PAN TROGLODYTES).

When evaluating the last 25 yr of morbidity and mortality from adult chimpanzees managed within the Association of Zoo and Aquarium Chimpanzee Species Survival Plan® for North American zoos, only two female chimpanzees were diagnosed with mammary neoplasia: one incidentally antemortem and one with a terminal metastatic neoplasia. When comparing this observation of prevalence of mammary neoplasia to humans, a substantial disparity is apparent. Mammary neoplasia is the second most common cancer in adult female humans, with a lifetime risk of 1:8 in the United States. The reason for the disparity between humans and chimpanzees, as closely related species, is unknown. The true prevalence in chimpanzees may be higher than currently noted, because routine examination of mammary tissue in chimpanzees is generally less complete than for other tissues postmortem, and antemortem assessment is generally limited to mammary palpation. This study was performed on intact, bilateral mammary glands harvested at postmortem examination of adult female chimpanzees (n = 7) from six institutions. With mammography, complete histopathologic sectioning, and genetic evaluation, the risk of mammary neoplasia was evaluated more thoroughly than during a typical postmortem exam in zoo populations during 2017-2019. No chimpanzees in the study were diagnosed with mammary neoplasia. Overall, this study supports the previous impression that chimpanzees do not develop mammary neoplasia at a similar rate as humans, even when comparable diagnostic modalities for evaluation are used.

Fatal Aberrant Parasite Migration of Echinuria uncinata in Two African Pygmy Geese (Nettapus auritus).

Two adult African pygmy geese (Nettapus auritus) were found dead with minimal clinical disease signs. Necropsy revealed aberrant migration of the nematode parasite Echinuria uncinata, as confirmed morphologically and through DNA sequencing. This common waterfowl parasite typically lives in the proventriculus, burying headfirst into the mucosa and laying eggs into the gastrointestinal lumen. In these geese, the parasites tunneled through the gastrointestinal tract wall to invade the coelomic cavity; from which, a substantial quantity of eggs found their way into the coelomic space and into the air sacs and lungs. This potential parasite migration should be monitored for in Anseriformes species that present with similar disease conditions, and the use of Daphnia species, the intermediate host, as a waterfowl feed source is not recommended.

Probable Enalapril Hepatotoxicity in a 13-Year-Old Male Western Lowland Gorilla: Pharmacologic Risks and Vigilance.

A 13-year-old male Western lowland gorilla presented acutely with a precipitous decline in health status from liver disease. Through diagnostic assessment, including serum chemistries and advanced imaging, it was diagnosed with probable hepatotoxicity resulting from its prescribed medication, enalapril. As one of several angiotensin converting enzyme inhibitors (ACE-I) available to zoo veterinarians, enalapril had been administered for treatment of mild ventricular hypertrophy diagnosed during routine examination 2.5 years prior to the presentation. The gorilla made a complete recovery with discontinuation of this medication, and provision of hepatoprotectants. Hepatotoxicity has been documented in humans receiving this product as an adverse drug reaction and is considered both rare and unpredictable in occurrence. In this event, an association was suspected with indulgent consumption of mulberry browse (Morus sp.) offered as nutritional enrichment immediately prior to clinical presentation and had potential impact on hepatic cytochrome P450 metabolism of the enalapril. Although ACE-I are important medications in this taxon due to its predisposition to cardiac disease, this event underscores the need for vigilance on the part of veterinarians and managers whenever pharmaceuticals are administered. Most drugs are modeled in a limited number of species but utilized in a wide variety, and unintended results are possible.

Novel Herpesvirus Associated With Oropharyngeal Squamous Cell Carcinoma in Smooth Green Snakes (Opheodrys vernalis).

During a 19-month period, 5 smooth green snakes (Opheodrys vernalis) maintained as an ex situ conservation colony presented with rapid clinical progression of locally invasive oropharyngeal squamous cell carcinoma. All 5 originated from the same wild source and were housed together or in close proximity. An infectious cause was considered likely, and nested conventional polymerase chain reaction (PCR) and in situ hybridization confirmed the presence of a novel alphaherpesvirus, Opheodrys herpesvirus 1, in the neoplastic tissue in 4 of the 5 snakes. Retrospective screening of previously submitted smooth green snakes by in situ hybridization did not detect virus in prior submissions from the colony. This report documents molecular characterization of an ophidian herpesvirus as well as colocalization of its viral nucleic acid with neoplastic transformation in snakes.

Blood groups in the Species Survival Plan®, European endangered species program, and managed in situ populations of bonobo (Pan paniscus), common chimpanzee (Pan troglodytes), gorilla (Gorilla ssp.), and orangutan (Pongo pygmaeus ssp.).

Blood groups of humans and great apes have long been considered similar, although they are not interchangeable between species. In this study, human monoclonal antibody technology was used to assign human ABO blood groups to whole blood samples from great apes housed in North American and European zoos and in situ managed populations, as a practical means to assist blood transfusion situations for these species. From a subset of each of the species (bonobo, common chimpanzee, gorilla, and orangutans), DNA sequence analysis was performed to determine blood group genotype. Bonobo and common chimpanzee populations were predominantly group A, which concurred with historic literature and was confirmed by genotyping. In agreement with historic literature, a smaller number of the common chimpanzees sampled were group O, although this O blood group was more often present in wild-origin animals as compared with zoo-born animals. Gorilla blood groups were inconclusive by monoclonal antibody techniques, and genetic studies were inconsistent with any known human blood group. As the genus and, specifically, the Bornean species, orangutans were identified with all human blood groups, including O, which had not been reported previously. Following this study, it was concluded that blood groups of bonobo, common chimpanzees, and some orangutans can be reliably assessed by human monoclonal antibody technology. However, this technique was not reliable for gorilla or orangutans other than those with blood group A. Even in those species with reliable blood group detection, blood transfusion preparation must include cross-matching to minimize adverse reactions for the patient.