Quality-of-Life Assessments in Zoo Animals: Not Just for the Aged and Charismatic.

Zoos should aim to provide all of their animals with a good quality of life (QoL) throughout all life stages. In parallel with the evolution of QoL assessment questionnaires and tools in human and domestic animal settings, in recent times, some individual zoos and zoo industry associations have incorporated such instruments into their animal management practices. This has been conducted predominantly to inform, monitor, and document end-of-life decision-making for large, charismatic mammals. There is scope to expand the use of these tools to improve their utility, validity, reliability, and value to an animal welfare program. Assessment of QoL is a complex task given that the notion being measured is abstract and self-determined, and the design and purpose of the tools to do this require careful consideration. This review explores the QoL concept as it applies to animals, the assessment indications and methodologies relevant to a zoo setting, and the importance of considering QoL at any life stage across species. An overview of current thinking and the applications and limitations of QoL evaluation of captive wild animals is offered to promote and aid facility practice reviews and to help direct future innovations that leverage concurrent and converging advances in zoo animal welfare science.

Evolutionarily Young African Rhinoceros Gammaretroviruses.

High-throughput sequences were generated from DNA and cDNA from four Southern white rhinoceros (Ceratotherium simum simum) located in the Taronga Western Plain Zoo in Australia. Virome analysis identified reads that were similar to Mus caroli endogenous gammaretrovirus (McERV). Previous analysis of perissodactyl genomes did not recover gammaretroviruses. Our analysis, including the screening of the updated white rhinoceros (Ceratotherium simum) and black rhinoceros (Diceros bicornis) draft genomes identified high-copy orthologous gammaretroviral ERVs. Screening of Asian rhinoceros, extinct rhinoceros, domestic horse, and tapir genomes did not identify related gammaretroviral sequences in these species. The newly identified proviral sequences were designated SimumERV and DicerosERV for the white and black rhinoceros retroviruses, respectively. Two long terminal repeat (LTR) variants (LTR-A and LTR-B) were identified in the black rhinoceros, with different copy numbers associated with each (n = 101 and 373, respectively). Only the LTR-A lineage (n = 467) was found in the white rhinoceros. The African and Asian rhinoceros lineages diverged approximately 16 million years ago. Divergence age estimation of the identified proviruses suggests that the exogenous retroviral ancestor of the African rhinoceros ERVs colonized their genomes within the last 8 million years, a result consistent with the absence of these gammaretroviruses from Asian rhinoceros and other perissodactyls. The black rhinoceros germ line was colonized by two lineages of closely related retroviruses and white rhinoceros by one. Phylogenetic analysis indicates a close evolutionary relationship with ERVs of rodents including sympatric African rats, suggesting a possible African origin of the identified rhinoceros gammaretroviruses. IMPORTANCE Rhinoceros genomes were thought to be devoid of gammaretroviruses, as has been determined for other perissodactyls (horses, tapirs, and rhinoceros). While this may be true of most rhinoceros, the African white and black rhinoceros genomes have been colonized by evolutionarily young gammaretroviruses (SimumERV and DicerosERV for the white and black rhinoceros, respectively). These high-copy endogenous retroviruses (ERVs) may have expanded in multiple waves. The closest relative of SimumERV and DicerosERV is found in rodents, including African endemic species. Restriction of the ERVs to African rhinoceros suggests an African origin for the rhinoceros gammaretroviruses.

KIT mutations in mast cell tumours from cheetahs (Acinonyx jubatus) and domestic cats (Felis catus).

Mast cell tumours (MCT) have been documented in numerous species and mutations within the KIT proto-oncogene are implicated in the neoplastic biology of mast cells in humans, dogs and cats. This study determined high KIT gene nucleotide and Kit amino acid sequence homology between several species known to suffer mast cell neoplasia and especially high sequence conservation between the cheetah (Acinonyx jubatus) and domestic cat (Felis catus) KIT sequences. As a result, we hypothesised that KIT mutations would exist in the neoplastic DNA of four cheetahs diagnosed with MCT from a recent case series. PCR and Sanger sequencing identified conservative exon 6 KIT mutations in two of the four cheetahs. The mutations were different between the two cheetahs. Only wild-type DNA in exons 6, 8, 9 and 11 of KIT was observed in the MCTs of the remaining two cheetahs. Twenty cutaneous MCTs from domestic cats were collected for KIT mutation comparison. Twelve tumours possessed a mutation within KIT exons 6, 8 or 9 (60%, 95% CI 38.5%-81.5%). No mutations were detected in exon 11. There was no significant association between domestic feline MCT KIT mutation status and tumour histological grade (traditional schematic, P = .934; Sabattini 2-tier schematic, P = .762) or mitotic index (P = .750). KIT mRNA and Kit protein sequences are conserved across species but the role of KIT in feline MCT pathogenesis is not completely understood.

MAST CELL TUMORS IN CHEETAH (ACINONYX JUBATUS): A CASE SERIES.

Mast cell tumors in nondomestic felids are rarely reported and their biological characteristics are not well described. A retrospective review of the pathology records of 52 zoo-housed cheetahs (Acinonyx jubatus) identified five cases of mast cell tumor, involving four closely related individuals. The age at initial presentation varied from 14 mo to 6 yr. Four cases presented as solitary or multiple cutaneous masses that were mostly slow growing, up to 20 mm diameter, and predominantly nonulcerated. The diagnosis was made by fine needle aspiration cytology of a lesion in one case and by excisional biopsy in the others. Histopathologically, the lesions resembled low- to intermediate-grade canine mast cell tumors, with variations in the degree of anisocytosis and anisokaryosis. Surgical excision was incomplete for 80% of the cutaneous lesions, but local recurrence was not observed in any case. One animal with cutaneous lesions subsequently developed fatal visceral mastocytosis involving the spleen, liver, and adrenal gland. There was no evidence of lymph node invasion or paraneoplastic gastrointestinal signs in any of the cases.

Retrospective anti-tetanus antibody responses of zoo-based Asian elephants (Elephas maximus) and rhinoceros (Rhinocerotidae).

Tetanus toxoids (TT) commercially available for use in horses and livestock are commonly used to vaccinate elephants and rhinoceros that are in human care. Although recommendations for booster intervals have changed in human and horse protocols to reduce the risks associated with hyper-immunity (i.e. B-cell anergy and hypersensitivity reactions) these have generally not been adopted in zoo protocols. Additionally, there is no evidence to demonstrate commercial TT immunogenicity in rhinoceros. In this study, a preliminary analysis of rhinoceros antibody responses to TT was conducted, in addition to an exploration of the impact of various booster frequencies on antibody responses in elephant. Retrospective analysis of archived serum samples was conducted for 9 Asian elephants (Elephas maximus), 7 southern black (Diceros bicornis minor), one southern white (Ceratotherium simum simum), and two greater one-horned (Rhinoceros unicornis) rhinoceros. Pre-vaccination (baseline) samples and those following priming vaccination (rhinoceros only), annual and non-annual boosters were targeted. A commercially available competitive ELISA kit was used to quantify serum anti-TT antibodies. Average baseline and post-vaccination anti-tetanus antibody concentrations were greater in elephant (92 mg/L ± 42, n = 3, N = 3; 125 ± 76, n = 82, N = 9) than in rhinoceros (47 mg/L ± 39, n = 8, N = 8; 44 mg/L ± 37, n = 16, N = 7). Rhinoceros antibody concentrations did not differ markedly following vaccinations from their naturally acquired high pre-vaccination concentrations. Eight elephants demonstrated antibody maintenance for 3-5 years without a tetanus booster. Additionally, although five out of nine elephants developed local reactions consistent with delayed type IV hypersensitivity following some boosters, there was no association between high antibody concentrations and increased incidence of adverse reactions. In addition, no decrease in antibody concentrations was detected as a result of annual vaccination in elephants, though this does not entirely rule out potential for B-cell anergy.

The identification of Theileria bicornis in captive rhinoceros in Australia.

Poaching of both black (Diceros bicornis) and white (Ceratotherium simum) rhinoceros in Africa has increased significantly in recent years. In an effort to ensure the survival of these critically endangered species, breeding programs were established in the 1990s in Australia, where a similar climate and habitat is available. In this study we examined blood samples from two C. simum, including a 16 yr old female (Aluka) who died in captivity, and a 17 yr old asymptomatic male (Umfana). Bloods from seven healthy D. bicornis housed at the zoo were also collected. All samples were tested for the presence of piroplasms via blood smear and PCR. A generic PCR for the 18S rRNA gene of the Piroplasmida revealed the presence of piroplasm infection in both dead and asymptomatic C. simum. Subsequent sequencing of these amplicons revealed the presence of Theileria bicornis. Blood smear indicated that this organism was present at low abundance in both affected and asymptomatic individuals and was not linked to the C. simum mortality. T. bicornis was also detected in the D. bicornis population (n = 7) housed at Taronga Western Plains Zoo using PCR and blood film examination; however only animals imported from Africa (n = 1) tested T. bicornis positive, while captive-born animals bred within Australia (n = 6) tested negative suggesting that transmission within the herd was unlikely. Phylogenetic analysis of the full length T. bicornis 18S rRNA genes classified this organism outside the clade of the transforming and non-transforming Theileria with a new haplotype, H4, identified from D. bicornis. This study revealed the presence of Theileria bicornis in Australian captive populations of both C. simum and D. bicornis and a new haplotype of the parasite was identified.

Undifferentiated carcinoma of the salivary gland in a chinchilla (Chinchilla lanigera).

A 12-year-old chinchilla (Chinchilla lanigera) developed a slow-growing, soft, fluctuating, nonpainful mass on the ventral neck with focally extensive alopecia over a period of approximately 8 months. On postmortem examination, an extensive, multilobulated, cystic, neoplastic mass extended subcutaneously over the ventral and lateral neck with metastatic spread to submandibular lymph nodes, spleen, liver, and lungs. Neoplastic cells were strongly positive for vimentin and pan-cytokeratin but were negative for alpha-smooth muscle actin, S100, and myosin; no intracytoplasmic myofibrils were detected on phosphotungstic acid hematoxylin staining. Histologic and immunohistochemical examination of the mass led to a diagnosis of undifferentiated carcinoma of the salivary gland and contributes to the paucity of knowledge concerning neoplasia in chinchillas.

Neosporosis in an aborted southern white rhinoceros (Ceratotherium simum simum) fetus.

In December 2008, a southern white rhinoceros (ãsimum simum) aborted a 7-mo gestation male fetus. On hematoxylin and eosin-stained sections of fetal tissues, foci of necrosis were noted in the hepatic parenchyma and were associated with low numbers of lymphocytes, plasma cells, and neutrophils. Protozoal zoites were identified within the hepatic lesions and within the cerebellum. Evaluations utilizing immunohistochemistry, polymerase chain reaction, and DNA sequencing identified the protozoan as Neospora caninum. A microsatellite analysis using MS10 marker showed a unique trinucletoide repeat pattern (ACT), (AGA)19 (TGA)8 distinct from all studied N. caninum to date. This is the first report of N. caninum-related abortion of a rhinoceros fetus of any species and the first report of polymerase chain reaction-confirmed N. caninum infection in any rhinoceros.