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West Nile virus (WNV) was first detected in Florida in July 2001, with 404 human cases reported to the Centers for Disease Control and Prevention as of February 2020. The subtropical climate of Florida is ideal for the mosquitoes that transmit WNV. We investigated the WNV seroprevalence in 3 NHP species housed outdoors at The Mannheimer Foundation in South Florida. From January to December 2016, 520 3 to 30 y old NHP were sampled at our 2 closed sites in Homestead and LaBelle: 200 rhesus macaques (Macaca mulatta), 212 cynomolgus macaques (Macaca fascicularis), and 108 hamadryas baboons (Papio hamadryas hamadryas). The presence of WNV IgG antibodies in these animals was determined by serum neutralization assays, which found a total seroprevalence of 14%. Seroprevalence was significantly higher in the baboons (29%) than the rhesus (11%) and cynomolgus (9%) macaques. The probability of seropositivity significantly increased with age, but sex and site did not significantly affect seroprevalence. The frequency of WNV seropositivity detected in these outdoor-housed NHP suggests that screening for WNV and other vector-borne diseases may be necessary prior to experimental use, particularly for infectious disease studies in which viremia or viral antibodies could confound results, and especially for populations housed outdoors in warm, wet climates. As no seropositive subjects demonstrated clinical signs of WNV and WNV exposure did not appear to significantly impact colony health, routine testing is likely unnecessary for most NHP colonies. However, WNV infection should still be considered as a differential diagnosis for any NHP presenting with nonspecific neurologic signs. Mosquito abatement plans and vigilant sanitation practices to further decrease mosquito and avian interaction with research NHP should also be considered.

Measles virus causes a highly infectious disease in NHP. Clinical signs range from asymptomatic to fatal, although measles virus is most well-known for its characteristic generalized maculopapular rash. Along with appropriate quarantine practices, restricted human access, and appropriate personal protective equipment, vaccines are used to combat the risk of infection. The canine distemper–measles vaccine (CDMV), administered at the manufacturer's standard dose (1.0 mL IM), has been shown to be effective against clinical measles disease in rhesus macaques (Macaca mulatta). The goal of the current study was to test whether doses smaller than the manufacturer's recommended dose stimulated adequate antibody production to protect against infection. We hypothesized that either 0.25 or 0.5 mL IM of CDMV would stimulate antibody production comparable to the manufacturer's recommended dose. We found that the 0.25-mL dose was less effective at inducing antibodies than either the standard (1.0 mL) or 0.5-mL dose, which both yielded similar titers. The primary implication of this study informs balancing resource allocation and providing efficacious immunity. By using half the manufacturer-recommended dose, the 50% cost reduction may provide sufficient monetary incentive to implement, maintain, or modify measles vaccination programs at NHP facilities.

An experimentally naïve, 9-y-old, intact male cynomolgus macaque was reported for bleeding from an unidentified site. Sedated physical examination indicated mild gingival separation from the lingual aspect of the upper right canine tooth as the source of the hemorrhage. Physical exam revealed a firm mass adhered to the left zygomatic arch, 2 subcutaneous nodules on the chest, and a large mass in the cranial abdomen. Radiographs revealed a large soft-tissue mass in the cranial abdomen and multifocal nodules in the caudal lung fields. On ultrasonography, the liver was grossly enlarged and contained a cavi- tated mass. Hematology and serum chemistry results demonstrated severe regenerative anemia with normal clotting times and adequate platelet count. For humane reasons, euthanasia was elected. On gross examination, the liver was markedly enlarged by an expansile mass primarily affecting the median lobe, with multiple, smaller nodules throughout the remaining lobes. Multifocal round, firm nodules were observed on the surface of all lung lobes and throughout the omentum. Histologic examination of the hepatic, cutaneous, osseous, and pulmonary lesions demonstrated well-defined, endothelium-lined vascular channels arranged in cords with abundant hemorrhage; endothelial-cell immunomarkers confirmed these results. On the basis of these findings, hepatic hemangiosarcoma, with metastases to the lungs, omentum, subcutis, and bone, was diagnosed. This case study is the first report of spontaneous hepatic hemangiosarcoma in a cynomolgus macaque and the first case with metastasis to bone in a NHP.

In rheumatoid arthritis research, NHP models of collagen-induced arthritis are important because these species share many immunologic and pathologic features with humans. In addition, serum levels of various cytokines in patients with rheumatoid arthritis have been studied as immune markers for disease prediction, early diagnosis, and effective therapeutic management. The purpose of this study was to identify changes in cytokine levels that occur during the development of collagen-induced arthritis in female cynomolgus macaques (n = 8) and to assess the relationships between these changes and various disease parameters. Blood samples were collected weekly before (week 0) and after (weeks 1 through 7) immunization with type II collagen; clinicopathologic and cytokine data from those samples and other clinical parameters were used in correlation analysis. Serum levels of IFN γ, chemokine (C-C motif) ligand 2 (CCL2), and IL6 showed significant changes after generation of collagen-induced arthritis. IFNγ levels showed a strong negative correlation with body weight (an indicator of general body condition), and CCL2 and IL6 showed moderate negative correlation with body weight. Serum IL6 levels showed moderate positive correlation with the soft tissue swelling score and strong positive correlation with serum C-reactive protein levels in our NHP model of collagen-induced arthritis. In addition, serum levels of matrix metalloproteinase 3 increased significantly after inoculation with type II collagen and showed a moderate positive correlation with serum levels of C-reactive protein, IL6, and IL15. These results suggest close correlations between various cytokines and disease parameters in NHP models of rheumatoid arthritis. These cytokines therefore potentially could be used as markers for monitoring the efficacy of novel treatments in NHP models of rheumatoid arthritis.

Chagas disease is a zoonotic vector-borne disease caused by infection with the protozoan parasite Trypanosoma cruzi. T. cruzi is found in Latin America and the Southern United States, where it infects many species, including humans and nonhuman primates (NHPs). NHPs are susceptible to natural infection and can develop clinical symptoms consistent with human disease, including Chagasic cardiomyopathy, gastrointestinal disease and transplacental transmission, leading to congenital infection. Due to evidence of Chagas transmission in Texas, this study hypothesized T. cruzi infection was present in a closed, outdoor-housed breeding colony of rhesus macaques (Macaca mulatta) located at a biomedical research facility in Central Texas. In addition, we questioned whether seropositive female rhesus macaques might experience reproductive complications consistent with maternal-fetal Chagas disease. The seroprevalence of T. cruzi infection in the colony was assessed using an Enzyme Linked Immunosorbant Assay (ELISA) to detect antibodies against Tc24 antigen as a screening assay, and a commercially available immunochromatographic test (Chagas Stat Pak) as a confirmatory assay. Retrospective serologic analysis was performed to confirm the status of all T. cruzi-infected animals between the years 2012 to 2016. The medical history of all seropositive and seronegative breeding females within the colony from 2012 to 2016 was reviewed to determine each animals' level of reproductive fitness. The percentage of T. cruzi-seropositive animals ranged from 6.7% to 9.7% in adult animals and 0% to 0.44% in juveniles or weanling animals, depending on the year. An overall 3.9% seroprevalence of T. cruzi infection was found in the total population. No significant differences in any measure of reproductive outcomes were identified between seropositive and seronegative females from 2012 to 2016. The lack of significant adverse reproductive outcomes reported here may help inform future management decisions regarding seropositive female rhesus macaques within breeding colonies.

Olive baboons (P. anubis) have provided a useful model of human diseases and conditions, including cardiac, respiratory, and infectious diseases; diabetes; and involving genetics, immunology, aging, and xenotransplantation. The development of a immunologically defined SPF baboons has advanced research further, especially for studies involving the immune system and immunosuppression. In this study, we compare normal immunologic changes of PBMC subsets, and their function in age-matched conventional and SPF baboons. Our results revealed that both groups have comparable numbers of different lymphocyte subsets, but phenotypic differences in central and effector memory T-cell subsets are more pronounced in CD4+ T cells. Despite equal proportions of CD3+ T cells among the conventional and SPF baboons, PBMC from the conventional group showed greater proliferative responses to phytohemagglutinin and pokeweed mitogen and higher numbers of IFNγ-producing cells after stimulation with concanavalin A or pokeweed mitogen, whereas plasma levels of the inflammatory cytokine TNFα were significantly higher in SPF baboons. Exposure of PBMC from conventional baboons to various Toll-like (TLR) ligands, including TLR3, TLR4, and TLR8, yielded increased numbers of IFNγ producing cells, whereas PBMC from SPF baboons stimulated with TLR5 or TLR6 ligand had more IFNγ-producing cells. These findings suggest that although lymphocyte subsets share many phenotypic and functional similarities in conventional and SPF baboons, specific differences in the immune function of lymphocytes could differentially influence the quality and quantity of their innate and adaptive immune responses. These differences should be considered in interpreting experimental outcomes, specifically in studies measuring immunologic endpoints.

Despite the lack of confirmed reports of an exogenous Simian betaretrovirus (SRV) isolated from baboons (Papio sp.), reports of simian endogenous gammaretrovirus (SERV) in baboons with complete genomes suggest that such viruses may be potentially infectious. In addition, serologic tests have repeatedly demonstrated antibody reactivity to SRV in baboons from multiple colonies. These findings complicate the management and use of such animals for research. To provide further insight into this situation, we performed in vitro and in vivo studies to determine if baboons are or can be infected with SRV. In our initial experiment, we were not able to isolate SRV from 6 seropositive or sero-indeterminate baboons by coculturing their peripheral blood mononuclear cells (PBMC) with macaque PBMC or permissive cell lines. In a subsequent experiment, we found that baboon PBMC infected in vitro with high dose SRV were permissive to virus replication. To test in vivo infectibil- ity, groups of naive baboons were infused intravenously with either (i) the same SRV tissue culture virus stocks used for the in vitro studies, (ii) SRV antibody positive and PCR positive macaque blood, (iii) SRV antibody positive or indeterminate, but PCR negative baboon blood, or (iv) SRV antibody and PCR negative baboon blood. Sustained SRV infection, as defined by reproducible PCR detection and/or antibody seroconversion, was confirmed in 2 of 3 baboons receiving tissue culture virus but not in any recipients of transfused blood from seropositive macaques or baboons. In conclusion, the data indicate that even though baboon cells can be infected experimentally with high doses of tissue culture grown SRV, baboons that are repeatedly SRV antibody positive and PCR negative are unlikely to be infected with exogenous SRV and thus are unlikely to transmit a virus that would threaten the SPF status of captive baboon colonies.

We here report a spontaneous case of primary myxoid liposarcoma of the greater omentum with subsequent transperitoneal recurrence. The primary mass was incidentally found during an exploratory laparotomy for a presumed diagnosis of trichobezoar or phytobezoar and was removed surgically. Histopathologic examination of the mass revealed the presence of a myxoid liposarcoma. Eleven months later, recurrence with severe transperitoneal sarcomatosis of the myxoid liposarcoma was noted and confirmed by necropsy and histopathology. A review of the literature revealed that liposarcoma in NHP conforms to the behavior and prognosis of this neoplasm in humans.

Serum cobalamin and folate concentrations can serve as surrogate markers of gastrointestinal disease in dogs and cats, where they can have diagnostic, therapeutic, and prognostic implications. Chronic disease of the gastrointestinal tract, particularly chronic lymphocytic enteritis (CLE), occurs frequently in captive common marmosets. The aims of this study were to validate a commercially available assay for measuring serum cobalamin and folate concentrations in common marmosets, to establish reference intervals for these analytes in healthy marmosets, and to measure serum concentrations in common marmosets with CLE. The commercial assay was linear, accurate, precise, and reproducible for the measurement of serum cobalamin and folate concentrations in common marmosets. In healthy marmosets, the serum cobalamin concentration ranged from 322 to 2642 pg/mL (n = 35) and serum folate concentration from 54.8 to 786.4 ng/mL (n = 37). Low serum folate concentrations were moderately sensitive (greater than 70%) for CLE, and low serum cobalamin concentrations were moderately (greater than 70%) specific for CLE. Both serum cobalamin and folate concentrations were relatively unchanged in marmosets during 120 to 220 d. Serum cobalamin and folate concentrations were stable for approximately 7 y when samples were stored at -80 °C. Additional studies are warranted to further study the clinical implications of low serum cobalamin and folate concentrations in common marmosets.

An 8-y-old female rhesus macaque (Macaca mulatta) presented for swelling of the left lower limb distal to the inguinal region and associated with the femoral artery. Physical and ultrasound examinations suggested an arteriovenous fistula combined with a pseudoaneurysm. After review of possible treatment options, we determined that open surgical repair was the best course of action. The pseudoaneurysm and arteriovenous fistula were surgically resected, and the macaque recovered without complication.

A 10-y-old cranially implanted rhesus macaque (Macaca mulatta) involved in visual research was presented for dull mentation and weight loss. Physical examination revealed alopecia and poor body conditioning, and bloodwork revealed marked hypercortisolemia (23 μg/dL). Differential diagnoses for hypercortisolemia, weight loss, and alopecia included Cushing and pseudo-Cushing syndromes. To further evaluate hypercortisolemia, we compared the urine cortisol:creatinine ratio (UCCR) at baseline and after low-dose dexamethasone suppression (LDDS) testing in the presenting animal and healthy naïve and implanted working monkeys. At baseline, UCCR was 10 times higher in the presenting macaque (118.1 ± 7.1) than in naïve animals (12.5 ± 12.8) and 3 times higher than in healthy implanted working macaques (44.4 ± 6.9); however, levels were suppressed similarly by dexamethasone in both the presenting animal and healthy controls. In addition, healthy implanted working macaques had significantly higher baseline UCCR levels than naïve controls, suggesting chronic stress in working animals. Abdominal ultrasonography and radiographs of the presenting animal revealed marked bilateral adrenal mineralization but no overt adrenal tumor or hyperplasia. Overall, these results excluded endogenous Cushing syndrome and prompted us to evaluate different causes of pseudo-Cushing syndrome, including depression. Using videorecordings to evaluate behavior, we used published criteria for macaque models of depression models, including huddling, to make a presumptive diagnosis of depression. The macaque was treated with fluoxetine (2 mg/kg PO daily), provided increased environmental enrichment, and followed over time by regular UCCR assessment and videorecordings. The animal improved clinically and behaviorally, and UCCR returned to levels observed in working implanted macaques (44.4) after 8 wk of treatment. This case highlights the potential effect of research-related work on stress and pathologic behaviors in macaques and demonstrates the utility of UCCR and LDDS for screening behavioral and hypothalamic-pituitary-adrenal abnormalities in these animals.

A wild-caught, research-naïve, adult male mustached tamarin (Saguinus mystax) experienced sudden onset of bilateral hindlimb paresis. Physical examination established the presence of paralysis and the lack of femoral pulses and deep pain in both legs. There were no signs of external trauma and, due to a poor prognosis, euthanasia was elected. Necropsy findings included pleural effusion, partial pulmonary atelectasis and congestion, dilatatory cardiomyopathy, a renal hemorrhagic infarct, and a thromboembolus located at the trifurcation of the distal abdominal aorta. The clinical and histologic findings were indicative of an aortic-iliac thrombosis.

Our investigation of indoor-housed cynomolgus macaques (Macaca fascicularis) by using automated identification followed by antibiotic susceptibility testing revealed 1 of 7 immunocompetent animals and 2 of 9 immunosuppressed monkeys as carriers of methicillin-resistant Staphylococcus aureus (MRSA). Follow-up management involving mupirocin treatment resulted in the conversion of the 3 MRSA carriers into MRSA-negative cases. Prospective assessment of newly imported monkeys involving 24-h culture of nasal swabs on chromogenic agar revealed that 22% (18 of 82 animals) were MRSA-positive. Mupirocin treatment successfully converted all of the MRSA-positive macaques into non-carriers, suggesting the feasibility of this simple, one-step screening procedure for rapidly identifying MRSA carriers in large cohorts. In addition, 8 animals that had been diagnosed MRSA-positive and subsequently treated with mupirocin demonstrated no recolonization during follow-up, even under immunosuppressive conditions. We propose rapid screening using chromogenic agar followed by mupirocin treatment as a time- and cost-effective regimen for managing MRSA in cynomolgus monkeys.

Endometriosis is a relatively common condition in women and some populations of adult female rhesus macaques. However, endometriosis with extensive smooth muscle proliferation, as occurs in endomyometrioma and uterus-like mass (ULM), is rare in women. This report describes a case of endometriosis with extensive smooth muscle metaplasia resembling multiple ULM in a 20-y-old female rhesus macaque. During a protocol-related procedure, a large, smooth, globoid, freely moveable mass was palpated in the midabdomen. Ultrasonography revealed a cystic structure from which dark brown fluid was aspirated. During exploratory laparotomy, an 8-cm spherical mass in the greater omentum and 3 additional masses (diameter, 2 to 5 cm) attached to the omentum were excised. Microscopic examination of the masses revealed numerous foci of ectopic endometrial glands and stroma frequently surrounded by bundles of smooth muscle and fibrous connective tissue. The gross and histologic lesions in this macaque bore many similarities to ULM in women. To our knowledge, this case represents the first report of endometriosis resembling a uterus-like mass in a NHP.

In this study, we evaluated the efficacy of combined treatment with ivermectin and fenbendazole (IVM-FBZ) for treating captive olive baboons (Papio anubis) infected with Strongyloides fülleborni and Trichuris trichiura, 2 common nematode parasites of these NHP. Infected baboons were treated for a total of 9 wk with ivermectin (400 μg/kg IM twice weekly) and fenbendazole (50 mg/kg PO once daily for 3 d; 3 rounds of treatment, 21 d apart). Five baboons naturally infected with both S. fülleborni and T. trichiura (n = 4) or S. fülleborni alone (n = 1) received the combination therapy; an additional baboon infected with both parasites served as a nontreated control. The efficacy of IVM-FBZ was measured as the reduction in fecal egg counts of S. fülleborni and T. trichiura as determined by quantitative fecal flotation examination after treatment of baboons with IVM-FBZ. All baboons treated with IVM-FBZ stopped shedding S. fülleborni and T. trichiura eggs by 8 d after treatment and remained negative for at least 161 d. The nontreated control baboon shed S. fülleborni and T. trichiura eggs throughout the study period. Our results indicate that the IVM-FBZ regimen was efficacious for treating olive baboons infected with S. fülleborni and T. trichiura.

A 6-d-old Indian-origin female rhesus macaque (Macaca mulatta) presented with bradycardia shortly after sedation with ketamine. No other cardiac abnormalities were apparent. Approximately 2 wk after the initial presentation, the macaque was again bradycardic and exhibited a regularly irregular arrhythmia on a prestudy examination. ECG, echocardiography, blood pressure measurement, SpO2 assessment, and a CBC analysis were performed. The echocardiogram and bloodwork were normal, but the infant was hypotensive at the time of echocardiogram. The ECG revealed ventricular parasystole. Ventricular parasystole is considered a benign arrhythmia caused by an ectopic pacemaker that is insulated from impulses from the sinus node. Given this abnormality, the macaque was transferred to a short-term study protocol, according to veterinary recommendation. On the final veterinary exam, a grade 3 systolic murmur and a decrease in arrhythmia frequency were noted. Gross cardiac lesions were not identified at necropsy the following day. Cardiac tissue sections were essentially normal on microscopic examination. This infant did not display signs of cardiovascular insufficiency, and a review of the medical record indicated normal growth, feed intake and activity levels. This case demonstrates the importance of appropriate screening of potential neonatal and juvenile research candidates for occult cardiovascular abnormalities. Whether the arrhythmia diagnosed in this case was truly innocuous is unclear, given the documented hypotension and the development of a systolic heart murmur.

Chronic diarrhea poses a significant threat to the health of NHP research colonies, and its primary etiology remains unclear. In macaques, the clinical presentation of intractable diarrhea and weight loss that are accompanied by inflammatory infiltrates within the gastrointestinal tract closely resembles inflammatory bowel disease of humans, dogs, and cats, in which low serum and tissue cobalamin (vitamin B12) levels are due to intestinal malabsorption. We therefore hypothesized that macaques with chronic idiopathic diarrhea (CID) have lower serum cobalamin concentrations than do healthy macaques. Here we measured serum cobalamin concentrations in both rhesus and pigtailed macaques with CID and compared them with those of healthy controls. Serum cobalamin levels were 2.5-fold lower in pigtailed macaques with CID than control animals but did not differ between rhesus macaques with CID and their controls. This finding supports the use of serum cobalamin concentration as an adjunct diagnostic tool in pigtailed macaques that present with clinical symptoms of chronic gastrointestinal disease. This use of serum vitamin B12 levels has implications for the future use of parenteral cobalamin supplementation to improve clinical outcomes in this species.

Brain MRI scans revealed various occipital horn variants in a pedigreed baboon colony consisting of Papio hamadryas anubis and its hybrids. We retrospectively characterized these variants and evaluated their relationships to epilepsy phenotypes and scalp EEG findings. MRI scans (3D, T1-weighted) from 208 baboons (female, 134 female; male, 74; age [mean ± 1 SD], 16 ± 5 y) were reviewed; 139 (67%) of these animals also underwent scalp EEG previously. Occipital horn variants included elongation (extension of the occipital ventricle behind the mediobasal origin of the calcarine fissure), which affected 23 baboons (11%; 7 bilateral, 9 left, 7 right), and elongation with enlargement (colpocephaly), which occurred in 30 baboons (14%; 7 bilateral, 11 left, 12 right). The incidence of the occipital horn variants did not differ according to age or prenatal or perinatal history. Colpocephaly was associated with craniofacial trauma but not with witnessed seizures. Abnormal scalp EEG findings, including interictal epileptic discharges, did not differ significantly among the occipital horn morphologies. This study is the first radiologic description of occipital horn variants, particularly colpocephaly, in baboons. Whereas colpocephaly is frequently associated with other radiologic and neurologic abnormalities in humans, it is mostly an isolated finding in baboons. Because craniofacial trauma can occur in the setting of seizure-related falls, its increased association with colpocephaly may reflect an increased risk of seizures or of traumatic brain injuries due to seizures. Colpocephaly in baboons needs to be characterized prospectively radiologically, neurologically, histopathologically, and genetically to better understand its etiology and clinical significance.

Bioabsorbable hemostatic agents such as oxidized regenerated cellulose are widely used to control intraoperative diffuse capillary bleeding. Compared with electrocautery or ligation, oxidized regenerated cellulose has the advantage of controlling bleeding without occluding the vessel lumen or causing thermal injuries to adjacent tissue. Although the manufacturer recommends removal of the material once hemostasis is achieved, oxidized regenerated cellulose is a bioabsorbable hemostatic agent and is often left in the surgical bed to prevent subsequent bleeding after surgical closure. However, noninvasive imaging techniques have revealed granulomatous foreign-body reactions that mimic infection or tumor recurrence. We present a case report of sterile peritonitis and granuloma formation secondary to the presence of oxidized regenerated cellulose after intestinal resection to excise a colonic adenocarcinoma in an aged rhesus macaque.

Measles is a highly contagious viral disease in NHP. The infection can range from asymptomatic to rapidly fatal, resulting in significant morbidity and mortality in captive populations. In addition to appropriate quarantine practices, restricted access, the immunization of all personnel in contact with NHP, and the wearing of protective clothing including face masks, measles immunization further reduces the infection risk. Commercially available measles vaccines are effective for use in NHP, but interruptions in their availability have prevented the implementation of ongoing, consistent vaccination programs. This need for a readily available vaccine led us to perform a broad, multicenter safety and immunogenicity study of another candidate vaccine, MVac (Serum Institute of India), a monovalent measles vaccine derived from live Edmonston-Zagreb strain virus that had been attenuated after 22 passages on human diploid cells.

Bone neoplasms in baboons (Papio spp) are rare, with only one confirmed case of osteosarcoma previously described in the literature. Over a 12-y period, 6 baboons at a national primate research center presented with naturally occurring osteosarcoma; 3 lesions affected the appendicular skeleton, and the remaining 3 were in the head (skull and mandible). The 6 cases presented were identified in members of a large outdoor-housed breeding colony. The subjects were not genetically related or exposed to the same research conditions. Diagnoses were made based on the presentation and radiographic findings, with histologic confirmation.

Two cases of clinical disease associated with extraintestinal Campylobacter infection were recently encountered in rhesus macaques (Macaca mulatta). The first case was that of a 3-y-old, male, rhesus macaque experimentally infected with SIV, who presented with abdominal pain and a midabdominal mass and was euthanized. Pathology findings included an abscess within the median liver lobe, fibrinopurulent peritonitis, and intestinal serositis with isolation of Campylobacter fetus from the blood, liver, and the hepatic abscess. The second case was that of a 1-mo-old, female, rhesus macaque who died with no apparent history of illness. Gross pathology findings included thin body condition and diarrheic staining of the perineum; histologically, acute multifocal hepatitis with intralesional bacteria was noted. Campylobacter coli was isolated from the liver and colon. Extraintestinal Campylobacter infection is uncommon in humans, usually occurring in immunocompromised subjects and most commonly manifesting as bacteremia. Extraintestinal Campylobacter infections in animals are rare but have been associated with bacteremia and cholecystitis. The macaques presented here were either immunocompromised due to SIV infection (case 1) or more vulnerable due to young age (case 2). These factors likely contributed to the extraintestinal spread of Campylobacter.

Macaques are the most common animal model for studies in vision research, and due to their high value as research subjects, often continue to participate in studies well into old age. As is true in humans, visual acuity in macaques is susceptible to refractive errors. Here we report a case study in which an aged macaque demonstrated clear impairment in visual acuity according to performance on a demanding behavioral task. Refraction demonstrated bilateral myopia that significantly affected behavioral and visual tasks. Using corrective lenses, we were able to restore visual acuity. After correction of myopia, the macaque's performance on behavioral tasks was comparable to that of a healthy control. We screened 20 other male macaques to assess the incidence of refractive errors and ocular pathologies in a larger population. Hyperopia was the most frequent ametropia but was mild in all cases. A second macaque had mild myopia and astigmatism in one eye. There were no other pathologies observed on ocular examination. We developed a simple behavioral task that visual research laboratories could use to test visual acuity in macaques. The test was reliable and easily learned by the animals in 1 d. This case study stresses the importance of screening macaques involved in visual science for refractive errors and ocular pathologies to ensure the quality of research; we also provide simple methodology for screening visual acuity in these animals.

Chagas disease (American trypanosomiasis) is caused by the protozoan parasite Trypanosoma cruzi. It is endemic in Latin America but also is found in the southern United States, particularly Texas and along the Gulf Coast. Typical clinical manifestations of Chagas disease are not well-characterized in rhesus macaques, but conduction abnormalities, myocarditis, and encephalitis and megaesophagus have been described. Here we report 2 cases of Chagas disease in rhesus macaques housed in the northwestern United States. The first case involved a geriatric male macaque with cardiomegaly, diagnosed as dilated cardiomyopathy on ultrasonographic examination. Postmortem findings included myocarditis as well as ganglioneuritis in the esophagus, stomach, and colon. The second case affected a geriatric female macaque experimentally infected with SIV. She was euthanized for a protocol-related time point. Microscopic examination revealed chronic myocarditis with amastigotes present in the cardiomyocytes, ganglioneuritis, and opportunistic infections attributed to her immunocompromised status. Banked serum samples from both macaques had positive titers for T. cruzi. T. cruzi DNA was amplified by conventional PCR from multiple tissues from both animals. Review of their histories revealed that both animals had been obtained from facilities in South Texas more than 12 y earlier. Given the long period of clinical latency, Chagas disease may be more prevalent in rhesus macaques than typically has been reported. T. cruzi infection should be considered for animals with unexplained cardiac or gastrointestinal pathology and that originated from areas known to have a high risk for disease transmission.

An adult, gravid, female pigtailed macaque (Macaca nemestrina) presented for facial swelling centered on the left mandible that was approximately 5 cm wide. Differential diagnoses included infectious, inflammatory, and neoplastic origins. Definitive antemortem diagnosis was not possible, and the macaque's condition worsened despite supportive care. Necropsy findings included a mandibular mass that was locally invasive and expansile, encompassing approximately 80% of the left mandibular bone. The mass replaced portions of the soft palate, hard palate, sinuses, ear canal, and the caudal-rostral calvarium and masseter muscle. Histologically, the mass was a neoplasm that was poorly circumscribed, unencapsulated, and infiltrative invading regional bone and soft tissue. The mass consisted of polygonal squamous epithelial cells with intercellular bridging that breached the epithelial basement membrane and formed invasive nests, cords, and trabeculae. The mitotic rate averaged 3 per 400× field of view, with occasional bizarre mitotic figures. Epithelial cells often exhibited dyskeratosis, and the nests often contained compact lamellated keratin (keratin pearls). The neoplasm was positive via immunohistochemistry for pancytokeratin, variably positive for S100, and negative for vimentin, smooth muscle actin, and desmin. The gross, histologic, and immunohistochemical findings were consistent with an aggressive oral squamous cell carcinoma. The neoplasm was negative via PCR for papilloma virus. In general, neoplasia in macaques is rare. Although squamous cell carcinomas are one of the most common oral neoplasia in many species, to our knowledge this case represents the first reported oral squamous cell carcinoma in a pigtailed macaque.

In 2008, clinical observations in our colony of sooty mangabeys (Cercocebus atys) suggested a high frequency of type 2 diabetes. Postmortem studies of diabetic animals revealed dense amyloid deposits in pancreatic islets. To investigate these findings, we screened our colony (97 male mangabeys; 99 female mangabeys) for the disease from 2008 to 2012. The overall prevalence of diabetes was 11% and of prediabetes was 7%, which is nearly double that reported for other primate species (less than 6%). Fructosamine and triglyceride levels were the best indicators of diabetes; total cholesterol and glycated hemoglobin were not associated with disease. Increasing age was a significant risk factor: prevalence increased from 0% in infants, juveniles, and young adults to 11% in adults and 19% in geriatric mangabeys. Sex, medroxyprogesterone acetate exposure, and SIV status were unrelated to disease. Weight was marginally higher in prediabetics, but body condition did not indicate obesity. Of the 49 mangabeys that were necropsied after clinical euthanasia or death from natural causes, 22 were diabetic; all 22 animals demonstrated pancreatic amyloid, and most had more than 75% of islets replaced with amyloid. We conclude that type 2 diabetes is more common in mangabeys than in other primate species. Diabetes in mangabeys has some unusual pathologic characteristics, including the absence of altered cholesterol levels and glycated hemoglobin but a robust association of pancreatic insular amyloidosis with clinical diabetes. Future research will examine the genetic basis of mangabey diabetes and evaluate additional diagnostic tools using imaging and serum markers.

Superficial decidualization of the endometrial stroma is an essential feature of the implantation stage of pregnancy in rhesus macaques and other primates. Decidualization involves proliferation of the endometrial stromal cells, with differentiation into morphologically distinct decidual cells. Previous reports involving nonpregnant rhesus monkeys have described local- ized and widespread endometrial decidualization in response to administration of progesterone and synthetic progestogens. Ectopic decidua or 'deciduosis' describes the condition in which groups of decidual cells are located outside of the endometrium, most often in the ovaries, uterus and cervix but also in various other organs. In humans, most cases of deciduosis are associated with normal pregnancy, and ectopic decidua can be found in the ovary in nearly all term pregnancies. Here we describe pronounced endometrial decidualization in 2 rhesus macaques. Both macaques had been treated long-term with medroxyprogesterone acetate for presumed endometriosis, which was confirmed in one of the macaques at postmortem examination. In one animal, florid extrauterine and peritoneal serosal decidualization was admixed multifocally with carcinomatosis from a primary colonic adenocarcinoma. Cells constituting endometrial and serosal decidualization reactions were immunopositive for the stromal markers CD10, collagen IV, smooth muscle actin, and vimentin and immunonegative for cytokeratin. In contrast, carcinomatous foci were cytokeratin-positive. To our knowledge, this report describes the first cases of serosal peritoneal decidualization in rhesus macaques. The concurrent presentation of serosal peritoneal decidualization with carcinomatosis is unique.

An incidental, asymptomatic, well-circumscribed, solitary, submucosal nodular mass was detected on the mucosal surface of the inner lower lip in a female cynomolgus macaque (age, approximately 2.4 y) during a juvenile chronic toxicology study. Grossly, the nodule was soft with brown to tan discoloration and measured approximately 4 mm in diameter. Microscopically, the nodule was covered by normal stratified squamous epithelium and composed of well-circumscribed irregular lobules containing hyperplastic and normal-appearing mucinous salivary gland acini and ducts, which were separated by thick connective tissue septae. In light of the gross pathology and results of microscopic examination, salivary gland hamartoma was diagnosed. This lesion resembles adenomatoid hyperplasia of mucous salivary glands in humans, which is a rare nonneoplastic swelling. To our knowledge, this case description is the first report of a cynomolgus macaque with the rare entity of lip salivary gland hamartoma, which likely represents adenomatous hyperplasia in humans.

Yersinia enterocolitica is a zoonotic gram-negative pathogen that causes mesenteric lymphadenitis, terminal ileitis, acute gastroenteritis, and septicemia in domestic animals and primates. In 2012, 46 captive African green monkeys (Chlorocebus aethiops sabaeus) died during an outbreak of acutely fatal enteric disease over a period of 1 mo on the island of St Kitts. The affected monkeys presented with a history of mucohemorrhagic diarrhea, marked dehydration, and depression. Fifteen bacterial isolates were recovered from the spleen, liver, and lungs of affected monkeys. All isolates were identified as Y. enterocolitica by biochemical analysis and sequence comparison of the 16S rRNA gene. Phenotypic and genotypic analysis of the recovered isolates revealed homogeneity among the recovered bacteria, and all isolates gave a random amplified polymorphic DNA pattern resembling that given by genotype D under serotypes O:7,8. This outbreak represents the first isolation and characterization of Y. enterocolitica as the causative agent of fatal enteric disease in primates in the Caribbean.

Neoplasia in juvenile (younger than 5 y) rhesus macaques has been estimated to represent only approximately 1.4% of all occurrences of spontaneous neoplasia. Here we report an unusual case of a 3.75-y-old primiparous female rhesus macaque that was euthanized due to poor prognosis associated with progressive anemia, marked hepatomegaly, and radiographic evidence of meta- static neoplasia. Postmortem examination revealed an invasive, hemorrhagic hepatic mass that effaced approximately 70% of the liver parenchyma and had evidence of metastatic spread to multiple abdominal organs, the lungs, and the pituitary gland. Neoplastic polygonal cells lined large necrohemorrhagic cavities and exhibited marked anisocytosis and anisokaryosis, with frequent multinucleate cells. There was no desmoplasia associated with the primary neoplasm or metastases. Immunohistochemical studies revealed the neoplastic cells to be diffusely reactive with pancytokeratin, cytokeratin 7, and cytokeratin 8/18 antibodies and rarely reactive with carcinoembryonic antigen antibodies. The cells did not react with vimentin, S100, CD31, or factor VIII antibodies. Tumor morphology and immunophenotype led to the diagnosis of anaplastic hepatocellular carcinoma. This report represents the first known case of metastatic liver neoplasia in a rhesus macaque. The young age of this animal and the aggressive nature of the neoplasm are highly unusual and reminiscent of adolescent onset hepatocellular carcinoma in humans.

We report a case of a generalized seizure in an adult female rhesus macaque ( Macaca mulatta) undergoing a urodynamic evaluation while she was anesthetized with continuous-infusion ketamine. The seizure presented with generalized tonic-clonic activity during bladder infusion with saline. The tonic-clonic phase was self-limited and was followed by focal facial twitching, which was interrupted by bolus administration of intravenous diazepam. The ictal event was documented as pressure oscillations during cystometrogram recordings and a period of external urethral sphincter muscle activation, which was detectable by electromyography. An acute decrease in urethral pressure was demonstrated at the end of the generalized seizures. Ketamine anesthesia combined with relatively rapid infusion of saline into the bladder may have contributed to the onset of seizures. In addition, this case highlights the value of having a fast-acting benzodiazepine agent available to stop continuous or residual seizure activity during diagnostic or experimental procedures in anesthetized nonhuman primates.

An aged male rhesus macaque in our colony had decreased appetite and a loss of interest in behavioral testing. CBC analysis revealed a regenerative, microcytic, hypochromic anemia with thrombocytosis, consistent with iron deficiency. A fecal occult blood test was positive. Ultrasound imaging revealed numerous, vascularized focal liver lesions that suggested metastases. The macaque's appetite continued to decrease, and he became more lethargic. At this point, the investigator elected to euthanize the macaque. At necropsy, the ileocolic junction was white and abnormally thickened, and the liver was pale tan with approximately 18 discrete white masses randomly scattered throughout the hepatic parenchyma. Histologically, the mass at the ileocolic junction was identified as an intestinal adenocarcinoma, whereas the liver masses were confirmed to be undifferentiated hepatic sarcomas. This case report describes a rhesus macaque that had 2 unrelated primary neoplasms. A review of the literature indicates that this rhesus macaque is the first reported to have an adenocarcinoma of the ileocolic junction and multiple hepatic sarcomas simultaneously.

Chronic diarrhea remains the principal burden in providing health care for nonhuman primates in biomedical research facilities. Although the exact etiology continues to puzzle nonhuman primate clinicians, recent research in humans has shown that restoring the indigenous microbial diversity may be successful in resolving cases of chronic diarrhea when other treatment modalities have failed. The process of restoring this microbial balance, known as fecal bacteriotherapy, uses the complete flora from a normal donor as a therapeutic probiotic mixture. In the current study, Indian-origin rhesus macaques were randomized into treatment (n = 7) and control (n = 6) groups to determine whether orally administered fecal bacteriotherapy would reduce the overall incidence of chronic diarrhea during a 60-d follow-up period in the treatment group compared with control macaques, which received a placebo. Although the treatment effect, determined by comparing the baseline fecal scores of the treatment and control groups, did not reach statistical significance, preprocedure and postprocedure fecal scores in the treatment group differed significantly. These findings are encouraging, and we hope that our study will motivate larger studies evaluating the use of fecal bacteriotherapy in nonhuman primates.

A 21-y-old female rhesus macaque presented with signs of internal and external ophthamoplegia, including anisocoria and ptosis. Ophthalmoplegia is the paralysis or weakness of one or more intraocular or extraocular muscles that control the movement of eye; this condition can be caused by neurologic or muscle disorders. The macaque was euthanized due to progression of clinical symptoms, and postmortem gross examination revealed a mass at the base of the brain attached to the meninges. Histopathologic examination led to the diagnosis of intracranial meningioma. Here we describe a case of intracranial meningioma with internal and external ophthalmoplegia in a rhesus macaque (Macaca mulatta).

Endometriosis is one of the most frequently encountered gynecologic diseases and a common cause of chronic pelvic pain and infertility. The pathophysiology of this syndrome can best be described as the presence of ectopic endometrium and a pelvic inflammatory process with associated immune dysfunction and alteration in the peritoneal environment. Macrophages play an important role in the progression and propagation of endometriosis. Alternative macrophage activation occurs in rodents and women with endometriosis but had not been examined previously in nonhuman primates. This case-control study aimed to characterize macrophage polarization in the ectopic and eutopic endometrial tissue of nonhuman primates with and without endometriosis. In addition, circulating cytokines in endometriosis cases and normal controls were investigated in an effort to identify serum factors that contribute to or result from macrophage polarization. Endometriosis lesions demonstrated increased infiltration by macrophages polarized toward the M2 phenotype when compared with healthy control endometrium. No serum cytokine trends consistent with alternative macrophage activation were identified. However, serum transforming growth factor α was elevated in macaques with endometriosis compared with healthy controls. Findings indicated that the activation state of macrophages in endometriosis tissue in nonhuman primates is weighted toward the M2 phenotype. This important finding enables rhesus macaques to serve as an animal model to investigate the contribution of macrophage polarization to the pathophysiology of endometriosis.

Since an epizootic and detection of clinical cases of tularemia (Francisella tularensis) in 1996 at the Oregon National Primate Research Center, only 8 cases were identified in the succeeding 13 y. However, within a period of 7 mo, primarily during Winter 2010, 6 rhesus macaques were confirmed positive for Francisella tularensis type B by the Centers for Disease Control and Prevention by culture and fluorescent antibody testing. All cases had similar gross pathologic findings, which included necrotizing splenitis and lymphadenitis. Recent colony management efforts have focused on minimizing nonhuman primate exposure to commonly observed reservoir species and controlling rodent access to corral-style housing. Strategies continue to evolve with regard to managing a large breeding colony of nonhuman primates in the presence of this threat.

Here we describe the successful surgical implementation of antibiotic-impregnated polymethylmethacrylate beads in a rhesus macaque (Macaca mulatta) with marked osteomyelitis. The macaque presented to the veterinary clinic with grossly contaminated bite wounds in the left ankle secondary to conspecific trauma. Radiographic findings were highly suggestive of osteomyelitis. Additional differential diagnoses included bony infarct, fracture, and cellulitis. In light of the location of the lesion and extensive tissue trauma, the animal had a poor prognosis. Systemic, broad-spectrum antibiotics were instituted. After 2 wk of care, lesions did not respond to empirical therapies. On consultation, a veterinary orthopedic surgeon at another facility recommended placement of antibiotic-impregnated polymethylmethacrylate beads at the sites of osteomyelitis. The animal underwent minor surgery in which beads were introduced into the wound. The monkey had a positive response to therapy. The animal regained full function and was returned to outdoor social housing. Veterinarians are encouraged to consider using antibiotic-impregnated polymethylmethacrylate beads when treating osteomyelitis in other nonhuman primates and in other traditional laboratory animal species.

A 5-y-old, male, rhesus macaque (Macaca mulatta) presented with a prominent mass slightly anteriomedial to the right stifle. On exam, multiple radiopaque masses were identified protruding from the mid- and distal femur. Lateral and anteroposterior radiographs of the right stifle region revealed multiple exophytic masses arising from the femur, with mild bony reaction of the proximal tibia. Histologic examination of biopsy tissue revealed woven and lamellar bone with granulation tissue and skeletal muscle. Because the macaque was exhibiting no lameness or signs of pain, we decided to monitor the progression of the masses. Minimal change was noted during the time prior to study termination at 6.5 y of age. Necropsy revealed that the bony masses were cartilage-capped lesions arising near the growth plate of the distal femur and midshaft of the femur and tibia. Histologic examination revealed chondro-osseous exophytic growths that blended imperceptibly with the cortex and spongiosa of the femur, consistent with a final diagnosis of multiple osteochondromas.

A 2.3-y-old female cynomolgus macaque (Macaca fascicularis) presented with a broken right tibia and fibula. Radiographs showed multiple cyst-like defects in all long bones. We suspected that both fractures were pathologic because they occurred through these defects. Ultrasonography, MRI, and dual X-ray absorptiometry revealed that the defects were filled with soft tissue. Grossly, the bones were abnormal in shape, and a gelatinous material filled the defects and the surrounding marrow cavity. Histologically, the gelatinous material was composed of fibrin and cartilage; few normal bone cells were seen. Genetic testing revealed extra material on the short arm of chromosome 8 in all tissues examined, but no copy number alterations of likely clinical significance were observed, and no abnormalities were found that were unique to the lesions. In light of the clinical signs and radiographic and pathologic findings, polyostotic fibrous dysplasia was diagnosed. This report represents the first documented case of fibrous dysplasia in a cynomolgus macaque.

Mycotic aortic aneurysm is a local, irreversible dilatation of the aorta associated with destruction of the vessel wall by infection and is a grave clinical condition associated with high morbidity and mortality in humans. Rupture of aortic aneurysms can be spontaneous, idiopathic, or due to severe trauma, and the condition has been associated with bacterial and, rarely, fungal infections in humans and animals. Here, we describe a case of ruptured spontaneous aortic aneurysm associated with zygomycetic infection in a 21-y-old female sooty mangabey. The animal did not present with any significant clinical signs before being found dead. At necropsy, she was in good body condition, and the thoracic cavity had a large amount of clotted blood filling the left pleural space and surrounding the lung lobes. Near the aortic arch, the descending thoracic aorta was focally perforated (diameter, approximately 0.15 cm), and clotted blood adhered to the tunica adventitia. The aortic intima had multiple, firm, pale-yellow nodules (diameter, 0.25 to 0.5 cm). Histopathologically, these nodules consisted of severe multifocal pyogranulomatous inflammation intermixed with necrosis, fibrin, and broad, infrequently septate, thin-walled fungal hyphae. Immunohistochemistry revealed fungal hyphae characteristic of Mucormycetes (formerly Zygomycetes), and PCR analysis identified the organism as Basidiobolus spp. Dissemination of the fungus beyond the aorta was not noted. Spontaneous aortic aneurysms have been described in nonhuman primates, but this is the first reported case of a ruptured spontaneous aortic aneurysm associated with entomophthoromycetic infection in a sooty mangabey.

Naturally occurring diabetes mellitus (DM) is common in several species of Old and New World nonhuman primates. Fructosamine values provide important information about recent glycemic control and can be useful in the diagnosis and management of DM. However, despite an abundance of reports in the literature describing spontaneous and induced DM in monkeys, few reference ranges are available for fructosamine. Reference ranges have been published for woolly monkeys (Lagothrix lagotricha), cynomolgus macaques (Macaca fascicularis), and stumptail macaques (Macaca arctoides) but currently are not available for rhesus macaques. At our institution, DM is a common diagnosis in aging rhesus macaques. Here we report a reference range for fructosamine in rhesus macaques. The overall range was 157 to 230 μmol/L, with male rhesus and macaques 10 y or older having significantly higher values than do female rhesus and macaques younger than 10 y, respectively. This range provides clinical veterinarians with an additional tool for evaluating glycemic control in rhesus macaques.

Dystocia (difficult labor) is an important component of the management of nonhuman primates and results in significant fetal and maternal morbidity and increased use of veterinary resources. Dystocias can arise from abnormalities of the maternal pelvis or fetus or uncoordinated uterine activity. Although risk factors for stillbirths have been established in nonhuman primates, risk factors for dystocias have not. The objective of this study was to determine maternal and fetal risk factors for dystocia in macaques. Retrospective data were collected from 83 pigtailed macaques (Macaca nemestrina) diagnosed with dystocia. The diagnosis of dystocia was made based on clinical or pathologic evidence. Maternal records of age, reproductive history, experimental history, clinical records, and fetal birth weight and any applicable fetal necropsy reports were reviewed. The gestational age of the fetus, the infant's birth weight, total previous births by the dam, and the proportions of both viable delivery (inverse effect) and surgical pregnancy interventions (direct effect) in the dam's history generated a model that maximized the experimental variance for predicting dystocia in the current pregnancy and explained 24% of the dystocia deliveries. The number of total previous births and proportion of previous cesarean sections accounted for the greatest effect. This model can identify individual dams within a colony that are at risk for dystocias and allow for changes in breeding colony management, more intense monitoring of dams at risk, or allocation of additional resources.

Rhesus rhadinovirus (RRV) and retroperitoneal fibromatosis herpesvirus (RFHV), 2 closely related γ2 herpesviruses, are endemic in breeding populations of rhesus macaques at our institution. We previously reported significantly different prevalence levels, suggesting the transmission dynamics of RRV and RFHV differ with regard to viral shedding and infectivity. We designed a longitudinal study to further examine the previously observed differences between RRV and RFHV prevalence and the potential influence of age, season, and housing location on the same 90 rhesus macaques previously studied. Virus- and host-genome-specific real-time PCR assays were used to determine viral loads for both RRV and RFHV in blood and saliva samples collected at 6 time points over an 18-mo period. Proportions of positive animals and viral load in blood and saliva were compared between and within viruses by age group, location, and season by using 2-part longitudinal modeling with Bayesian inferences. Our results demonstrate that age and season are significant determinants, with age as the most significant factor analyzed, of viremia and oral shedding for both RRV and RFHV, and these pathogens exhibit distinctly different patterns of viremia and oral shedding over time within a single population.

An 8.5-mo-old female rhesus macaque was examined for an apparent lump on the right arm, below the elbow. The macaque showed no signs of pain or discomfort. Examination revealed that the lump was actually a bend in the forearm. Radiography demonstrated that some of the long bones of the animal were bowed. Differential diagnoses included rickets, hyperparathyroidism, pseudohyperparathyroidism, and a growth dysplasia. No other similar abnormalities in animals from that cage or any other enclosure in our large colony were observed. Blood chemistries and a complete hemogram were within normal limits for a macaque of this age. Serum was submitted for a vitamin D profile that included assays for parathyroid hormone, 25-hydroxyvitamin D, and ionized calcium. Serum samples from sex- and age-matched normal controls were sent for comparison and to establish a baseline profile. The affected animal had vitamin D levels comparable to unaffected controls. Bone biopsies appeared normal for a macaque of this age. Fluorine levels in the drinking water supply were within acceptable limits. Consistent with the information available, a diagnosis of idiopathic camptomelia, or bowing of the long bones, was made. In humans, developmental camptomelia is associated with several bone dysplasias in infants and children. These conditions are thought to be caused by genetic mutations in enzymes or transcription factors that control development of the epiphyses and are almost always associated with other lethal and nonlethal developmental abnormalities.

We here describe a case of recurrent gingival enlargement in an olive baboon (Papio anubis). This baboon (a male breeder that had not undergone any experimental procedures) also had shown mild gingival enlargement the 2 y prior to the current lesion. Clinical and histopathologic findings confirmed a diagnosis of idiopathic gingival enlargement.

Two pair-housed, 1-y-old common marmosets (Callithrix jacchus) had intermittent loose feces and weight loss for approximately 2 mo. Cryptosporidum parvum was identified by ELISA in the feces of both animals. CBC and blood chemistry values, including liver enzymes, were within normal range. Both marmosets were treated with the antibiotic paromomycin (15 mg/kg PO) twice daily for 28 d. Resolution of clinical signs coincided with treatment. Three follow-up samples, taken 2 wk apart after treatment was finished, were negative for cryptosporidium ELISA in both animals. Paromomycin should be considered for treatment of cryptosporidiosis in marmosets.

Here we describe a case of zygomycosis in a 4-y-old male cynomolgus monkey (Macaca fascicularis) newly received into our facility. Results of physical exam, clinical chemistry analysis, hematology, and tuberculin skin testing and routine thoracic radiographs performed during the quarantine period are reported. Routine chest radiographs taken during the quarantine period revealed enlargement of the cranial mediastinum. During quarantine, the macaque developed severe respiratory distress and was euthanized. Microscopic examination of tissue collected at the postmortem exam revealed nonseptated, branching hyphae in sections of the stomach and mediastinal lymph nodes consistent with a zygomycete. This is the first reported case of zygomycosis in a cynomolgus monkey.

A chronically catheterized 14-y-old male rhesus macaque (Macaca mulatta) was reported for recurrent scrotal swelling. The scrotum was enlarged and warm to touch, and associated skin was noted to be lichenified on physical examination. The penis could not be extruded due to preputial swelling. Results from the following diagnostic tests were all unremarkable or within normal limits: scrotal aspirate, hematology, serum biochemistries, urinalysis, and radiography of the thorax, scrotum, and abdomen. Ultrasonography of lower extremities identified thrombi in bilateral iliac veins and left femoral vein. Collateral circulation surrounding the left femoral vein permitted some compensatory venous return. The left femoral vein of this animal had been catheterized approximately 2 mo before initial presentation. A coagulation panel revealed a positive D-dimer test, indicative of elevated levels of fibrin degradation products due to active thrombus breakdown. Enoxaparin sodium, a low-molecular-weight heparin for human use, was administered at 20 mg subcutaneously once daily for 10 d to treat occlusive venous thrombi. After enoxaparin treatment, the edema was greatly decreased. To achieve complete resolution, a second course of enoxaparin was administered 2 months after the first. Ultrasonography of the pelvic vasculature 6 mo after completion of therapy showed marked thrombus resolution, allowing for bilateral patency in the iliac and femoral veins. Follow-up evaluation revealed that D-dimer values were negative as well. This case demonstrates the novel application of the human medication enoxaparin to treat clinical signs of deep vein thrombosis in a chronically catheterized rhesus macaque.

An adult, male, rhesus macaque presented with pruritus and a focal, exudative, inflamed, erythematous skin lesion of approximately 2 cm in diameter on the ventral aspect of the mandible. The lesion resolved after 10 d of treatment with 1% chlorhexidine solution and triple-antibiotic ointment. However, the skin lesion subsequently recurred several times over a 2-mo period. A punch biopsy was performed, and histological changes were most consistent with a diagnosis of atopic dermatitis. Treatment with topical tacrolimus ointment, an immunosuppressive drug, proved successful in the resolution of all clinical signs after 4 mo. According to a literature review, this article is the first report of the use of tacrolimus ointment as a topical treatment of atopic dermatitis in a rhesus macaque.