Tara M. Harrison

Antibodies to canine and feline viruses in spotted hyenas (Crocuta crocuta in the masai mara national reserve

Spotted hyenas (Crocuta crocuta) are abundant predators in the Serengeti ecosystem and interact with other species of wild carnivores and domestic animals in ways that could encourage disease transmission. Hyenas also have a unique hierarchical social system that might affect the flow of pathogens. Antibodies to canine distemper virus (CDV), feline immunodeficiency virus (FIV), feline panleukopenia virus/canine parvovirus (FPLV/CPV), feline coronavirus/feline infectious peritonitis virus (FECV/FIPV), feline calicivirus (FCV), and feline herpesvirus 1 (FHV1) have been detected in other Serengeti predators, indicating that these viruses are present in the ecosystem. The purpose of this study was to determine whether spotted hyenas also had been infected with these viruses and to assess risk factors for infection. Serum samples were collected between 1993 and 2001 from 119 animals in a single clan for which behavioral data on social structure were available and from 121 hyenas in several other clans. All animals resided in the Masai Mara National Reserve. Antibodies to CDV, FIV, FPLV/CPV, FECV/FIPV, FCV, and FHV1 were present in 47%, 35%, 81%, 36%, 72%, and 0.5% of study hyenas, respectively. Antibody prevalence was greater in adults for FIV and FECV/FIPV, and being a female of high social rank was a risk factor for FIV. Hyenas near human habitation appeared to be at lower risk to have CDV, FIV, and FECV/FIPV antibodies, whereas being near human habitation increased the risk for FPLV/CPV antibodies. Canine distemper virus and FECV/FIPV antibody prevalence varied considerably over time, whereas FIV, FPLV/CPV, and FCV had a stable, apparently endemic temporal pattern. These results indicate that hyenas might play a role in the ecology of these viruses in the Serengeti ecosystem. The effect of these viruses on hyena health should be further investigated. The lower prevalence of CDV antibody–positive hyenas near human habitation suggests that reservoirs for CDV other than domestic dogs are present in the Serengeti ecosystem.

Diet is a major factor governing the fecal butyrate-producing community structure across Mammalia, Aves and Reptilia.

Butyrate-producing bacteria have an important role in maintaining host health. They are well studied in human and medically associated animal models; however, much less is known for other Vertebrata. We investigated the butyrate-producing community in hindgut-fermenting Mammalia (n=38), Aves (n=8) and Reptilia (n=8) using a gene-targeted pyrosequencing approach of the terminal genes of the main butyrate-synthesis pathways, namely butyryl-CoA:acetate CoA-transferase (but) and butyrate kinase (buk). Most animals exhibit high gene abundances, and clear diet-specific signatures were detected with but genes significantly enriched in omnivores and herbivores compared with carnivores. But dominated the butyrate-producing community in these two groups, whereas buk was more abundant in many carnivorous animals. Clustering of protein sequences (5% cutoff) of the combined communities (but and buk) placed carnivores apart from other diet groups, except for noncarnivorous Carnivora, which clustered together with carnivores. The majority of clusters (but: 5141 and buk: 2924) did not show close relation to any reference sequences from public databases (identity <90%) demonstrating a large ‘unknown diversity’. Each diet group had abundant signature taxa, where buk genes linked to Clostridium perfringens dominated in carnivores and but genes associated with Ruminococcaceae bacterium D16 were specific for herbivores and omnivores. Whereas 16S rRNA gene analysis showed similar overall patterns, it was unable to reveal communities at the same depth and resolution as the functional gene-targeted approach. This study demonstrates that butyrate producers are abundant across vertebrates exhibiting great functional redundancy and that diet is the primary determinant governing the composition of the butyrate-producing guild.

Malignant Lymphoma in African Lions (Panthera Leo)

Malignant lymphoma has become an increasingly recognized problem in African lions (Panthera leo). Eleven African lions (9 male and 2 female) with clinical signs and gross and microscopic lesions of malignant lymphoma were evaluated in this study. All animals were older adults, ranging in age from 14 to 19 years. Immunohistochemically, 10 of the 11 lions had T-cell lymphomas (CD3+, CD79a–), and 1 lion was diagnosed with a B-cell lymphoma (CD3–, CD79a+). The spleen appeared to be the primary site of neoplastic growth in all T-cell lymphomas, with involvement of the liver (6/11) and regional lymph nodes (5/11) also commonly observed. The B-cell lymphoma affected the peripheral lymph nodes, liver, and spleen. According to the current veterinary and human World Health Organization classification of hematopoietic neoplasms, T-cell lymphoma subtypes included peripheral T-cell lymphoma (4/11), precursor (acute) T-cell lymphoblastic lymphoma/leukemia (2/11), chronic T-cell lymphocytic lymphoma/leukemia (3/11), and T-zone lymphoma (1/11). The single B-cell lymphoma subtype was consistent with diffuse large B-cell lymphoma. Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) testing by immunohistochemistry on sections of malignant lymphoma was negative for all 11 lions. One lion was seropositive for FeLV. In contrast to domestic and exotic cats, in which B-cell lymphomas are more common than T-cell lymphomas, African lions in this study had malignant lymphomas that were primarily of T-cell origin. Neither FeLV nor FIV, important causes of malignant lymphoma in domestic cats, seems to be significant in the pathogenesis of malignant lymphoma in African lions.

Surgical Amputation of a Digit and Vacuum-Assisted-Closure (V.A.C.) Management in a Case of Osteomyelitis and Wound Care in an Eastern Black Rhinoceros (Diceros bicornis michaeli)

Abstract:  A 14-yr-old female eastern black rhinoceros (Diceros bicornis michaeli) presented with progressive suppurative osteomyelitis in her left hind lateral toe. β-Hemolytic Streptococcus sp. was isolated. The animal was treated with multiple systemic antibiotics, and topical wound cleansing. Repeated debridements and nail trimmings were performed for 5 mo prior to electing amputation. The toe was surgically amputated under general anesthesia between the first and second phalanges. Analgesia was diffused into the wound topically via a catheter and elastomeric pump. The open amputation site was covered with adherent drapes and a negative-pressure wound therapy device provided vacuum-assisted closure (V.A.C.®) for 72 hr. Three months later this animal developed a deep dermal ulcer on the lateral aspect of the right hind limb, at the level of the stifle. Methicillin-resistant Staphylococcus aureus was isolated. The wound was managed by initial daily lavage, followed by 1 mo of V.A.C. therapy, with 72 hr between dressing changes. Clinically, this therapy expedited the formation of healthy granulation tissue and overall healing was accelerated. The animal tolerated the machine and bandage changes well via operant conditioning. The use of negative-pressure wound therapy appeared to shorten time to resolution of slow-healing wounds in black rhinoceros.

Systemic calicivirus epidemic in captive exotic felids.

Abstract A 5-day-old, mother-raised, Amur tiger cub (Panthera tigris altaica) presented with tongue ulcerations. Identical lesions appeared and progressed to sloughing of the tongue in the three littermates of this cub the following day. The lesions progressed in all cubs to include sloughing of the carpal, tarsal, metacarpal, and metatarsal foot pad epithelium. Oral ulcerations were also noted in adult African lions (Panthera leo) and Amur tigers (Panthera tigris altaica), but not in two adult snow leopards (Panthera uncia) housed in the same building. All adult cats had been previously vaccinated for common feline diseases including feline calicivirus (FCV). Detection of FCV RNA in oral secretions by a real-time reverse transcription polymerase chain reaction assay (RRT-PCR) confirmed FCV infection in the tiger cubs and one lion. A male lion and a male tiger cub died during the disease outbreak. RRT-PCR confirmed FCV in multiple tissues in both of these animals. A stray cat live-trapped outside the feline building during the epidemic was found to be positive for FCV by virus isolation and was thought to be the source of infection.

TREATMENT OF MALIGNANT LYMPHOMA IN AN AFRICAN LION (PANTHERA LEO)

Abstract A 14 yr-old male, vasectomized African lion (Panthera leo) exhibited mild weight loss despite adequate appetite. Splenomegaly was diagnosed on physical examination. On the basis of hematology and clinical pathology, malignant lymphoma with chronic lymphocytic leukemia was diagnosed. Abdominal exploratory surgery and splenectomy were performed. Histologic examination and immunohistochemistry confirmed a small cell peripheral T-cell lymphoma. Initial treatments consisted of doxorubicin and prednisone, with later addition of lomustine. The lion remained in clinical remission at 2 mo, 6 mo, and 12 mo postchemotherapy physical examinations. The lion survived 504 days from initial diagnosis. At necropsy, the only lesions consistent with lymphoma were localized epitheliotrophic infiltrates of small neoplastic T lymphocytes within the nasopharyngeal epithelium and the underlying submucosa observed on microscopic examination.

Use of Positive Reinforcement Conditioning to Monitor Pregnancy in an Unanesthetized Snow Leopard (Uncia uncia) via Transabdominal Ultrasound

Closely monitoring snow leopard (Uncia uncia) fetal developments via transabdominal ultrasound, with minimal stress to the animal, was the goal of this project. The staff at Potter Park Zoo has used the principles of habituation, desensitization, and positive reinforcement to train a female snow leopard (U. uncia). Ultrasound examinations were preformed on an unanesthetized feline at 63 and 84 days. The animal remained calm and compliant throughout both procedures. Fetuses were observed and measured on both occasions. The absence of anesthesia eliminated components of psychologic and physiologic stress associated with sedation. This was the first recorded instance of transabdominal ultrasound being carried out on an unanesthetized snow leopard. It documents the feasibility of detecting pregnancy and monitoring fetal development via ultrasound. Zoo Biol 27:78-85, 2008. (c) 2007 Wiley-Liss, Inc.

Toxoplasma gondii in an African crested porcupine (Hystrix cristata).

An adult female crested porcupine (Hystrix cristata) was evaluated for acute onset of neurologic signs including head tilt, circling, and ataxia. She was found dead in her holding area 2 days after initially exhibiting clinical signs. Necropsy was unremarkable. Histopathology of brain tissue revealed the presence of protozoal cysts associated with inflammation as the underlying cause of clinical signs and death. Immunohistochemical staining of brain tissue for Toxoplasma gondii was strongly positive. PCR on fresh brain confirmed T. gondii as the causative organism. An adult male in the same enclosure has demonstrated similar neurologic signs over the past 3 years and has failed to respond to various medical treatments. Clinical disease associated with T. gondii has not been previously reported in this porcupine species or any other Old World porcupines, although there are several reports of clinical toxoplasmosis involving New World porcupine species.

SURVEILLANCE FOR SELECTED BACTERIAL AND TOXICOLOGIC CONTAMINANTS IN DONATED CARCASS MEAT FED TO CARNIVORES

Abstract Wildlife Safari, a zoo located in Winston, Oregon, has fed donated carcass meat as a diet to carnivores for over 30 yr. Carcass meat is an alternative to commercially prepared meat. Donated meat arrives at Wildlife Safari as an entire animal. Cattle (Bos taurus), horse (Equus caballus), deer (Odocoileus hemionus), and elk (Cervus elaphus roosevelti) have been donated. Bacterial testing was performed on site with the use of Neogen Reveal® immunosorbent assays. Testing focused on Salmonella spp., Listeria spp., and Escherichia coli O157:H7. Twenty-five meat samples were randomly selected from 50 meat samples for the bacterial detection tests. Twenty-eight percent of the meat samples were positive for Salmonella spp. (n = 25). One sample was positive for Listeria spp. None of the meat samples were positive for Escherichia coli O157:H7 (n = 25). Thirty-two meat samples were analyzed off site for organic contaminants with the use of gas chromatography/mass spectrometry at Michigan State Universitys Diagnostic Center for Population and Animal Health. Specific organic contaminants tested for were barbiturates, phenylbutazone, flunixin meglumine, and xylazine. None of the meat samples were found to have evidence of these or any other common organic toxicants. As monitored, carcass meat appears to be a reasonably safe food source for carnivores.

ENROFLOXACIN-INDUCED RETINOPATHY IN A GUANACO (LAMA GUANICOE)

Abstract A 4-yr-old male guanaco (Lama guanicoe) in a multispecies exhibit presented with a laceration in the axillary region. The laceration was surgically repaired. Medical treatment was initiated with penicillin G procaine and benzathine (1920 IU/kg, i.m., s.i.d. for 14 days), and enrofloxacin (2.4 mg/kg, i.m., s.i.d. for 14 days). The animal was later treated with trimethoprim-sulfadiazine (24 mg/kg, p.o., s.i.d. for 10 days). Twenty-six days after initial presentation, the guanaco was suspected to be blind. An ophthalmic examination confirmed retinal damage. On postmortem histological evaluation, there was outer retinal atrophy that was most severe in the central retina with localized foci of complete retinal atrophy; lesions were similar to those observed in enrofloxacin retinal toxicity in cats.