CardiOvascular examination in awake Orangutans (Pongo pygmaeus pygmaeus): Low-stress Echocardiography including Speckle Tracking imaging (the COOLEST method).

INTRODUCTION: Cardiovascular diseases have been identified as a major cause of mortality and morbidity in Borneo orangutans (Pongo pygmaeus pygmaeus). Transthoracic echocardiography is usually performed under anesthesia in great apes, which may be stressful and increase risks of peri-anesthetic complications in case of cardiac alteration. The aim of the present pilot study was hence to develop a quick and non-stressful echocardiographic method (i.e., the COOLEST method) in awake Borneo orangutans (CardiOvascular examination in awake Orangutans: Low-stress Echocardiography including Speckle Tracking imaging) and assess the variability of corresponding variables. MATERIALS AND METHODS: Four adult Borneo orangutans trained to present their chest to the trainers were involved. A total of 96 TTE examinations were performed on 4 different days by a trained observer examining each orangutan 6 times per day. Each examination included four two-dimensional views, with offline assessment of 28 variables (i.e., two-dimensional (n = 12), M-mode and anatomic M-mode (n = 6), Doppler (n = 7), and speckle tracking imaging (n = 3)), representing a total of 2,688 measurements. A general linear model was used to determine the within-day and between-day coefficients of variation. RESULTS: Mean±SD (minimum-maximum) images acquisition duration was 3.8±1.6 minutes (1.3-6.3). All within-day and between-day coefficients of variation but one (n = 55/56, 98%) were <15%, and most (51/56, 91%) were <10% including those of speckle tracking systolic strain variables (2.7% to 5.4%). DISCUSSION: Heart morphology as well as global and regional myocardial function can be assessed in awake orangutans with good to excellent repeatability and reproducibility. CONCLUSIONS: This non-stressful method may be used for longitudinal cardiac follow-up in awake orangutans.

USE OF COMPUTED TOMOGRAPHY (CT) TO DETERMINE THE SENSITIVITY OF CLINICAL SIGNS AS A DIAGNOSTIC TOOL FOR RESPIRATORY DISEASE IN BORNEAN ORANGUTANS (PONGO PYGMAEUS).

Orangutans are noteworthy among great apes in their predilection for chronic, insidious, and ultimately fatal respiratory disease. Termed Orangutan Respiratory Disease Syndrome (ORDS), this cystic fibrosis-like disease is characterized by comorbid conditions of sinusitis, mastoiditis, airsacculitis, bronchiectasis, and recurrent pneumonia. The aim of this retrospective study was to determine the sensitivity of clinical signs in the diagnosis of ORDS in Bornean orangutans (Pongo pygmaeus) compared with the gold standard for diagnosis via computed tomography (CT). We retrospectively compared observed clinical signs with CT imaging in a population of clinically affected animals at an orangutan rescue center in southeastern Borneo. From August 2017 to 2019, this center housed 21 ORDS-affected animals, all of which underwent CT imaging to delineate which areas of the respiratory tract were affected. We reviewed clinical signs recorded in medical records and keeper observation notes for each individual for the period of 2 years prior to the date of the CT scan. A chi-square test of association was used to assess whether the observed clinical signs could predict the results of CT imaging. Results show that clinical signs may not be sensitive indicators in predicting respiratory disease identified by CT imaging. Based on the results of this study, clinical signs appear to be very poor predictors of underlying respiratory pathology in orangutans, based on high P-values, low sensitivity, and low specificity. This result is observed even with clinical signs data gathered over a full 24-mo period prior to CT scan performance. The findings of this study suggest the need for advanced imaging to properly diagnose and manage the most common health issue of captive orangutans.

GREAT APE HEART PROJECT GUIDELINES FOR THE ECHOCARDIOGRAPHIC ASSESSMENT OF GREAT APES.

Cardiovascular disease (CVD) has been identified as a major cause of mortality in all four great ape taxa in zoologic institutions. In an effort to better understand and treat CVD in captive great apes, a program called the Great Ape Heart Project (GAHP), based at Zoo Atlanta, collects and maintains a database of echocardiograms and other relevant medical information relating to the cardiac health status of great apes. Cardiac health assessments have become standard practice among North American zoos that house great apes and are recommended by all four great ape Species Survival Plans (SSP) for the assessment of CVD in captive great apes. As of December 31, 2017, more than 70 ape-holding institutions have submitted approximately 1,100 cardiac examinations of great apes to the GAHP, information from which is stored in the GAHP database. Transthoracic echocardiography is one of the most practical and cost-effective diagnostic imaging techniques for the evaluation of cardiac function in great apes. Standardization of echocardiographic measurements is critical for maximizing the diagnostic value of an echocardiographic exam and for utilization of stored information in comparative studies within and between the great ape taxa. The following manuscript offers suggestions for standardization of nomenclature, imaging technique, echocardiographic measurements, data storage, and reporting of cardiac exams for submission into the GAHP database with the goal of promoting consistency and quality in data collection.

Lipoid pneumonia in an orangutan (Pongo abelii) with chronic respiratory problems.

An orangutan (Pongo abelii) presented with chronic respiratory problems. Cytological evaluation of the bronchoalveolar lavage fluids revealed macrophages with well-circumscribed intracytoplasmic clear vacuoles and lipid droplets in the background, confirmed by Oil Red O staining. The findings were indicative of lipoid pneumonia. This is the first report of lipoid pneumonia in an orangutan.

A case of benign osteogenic tumour in Homo naledi: Evidence for peripheral osteoma in the U.W. 101-1142 mandible.

The reported incidence of neoplasia in the extinct hominin record is rare. We describe here the first palaeopathological analysis of an osteogenic lesion in the extinct hominin Homo naledi from Dinaledi Cave (Rising Star), South Africa. The lesion presented as an irregular bony growth, found on the right lingual surface of the body of the adult mandible U.W. 101-1142. The growth was macroscopically evaluated and internally imaged using micro-focus x-ray computed tomography (µCT). A detailed description and differential diagnosis were undertaken using gross and micromorphology, and we conclude that the most probable diagnosis is peripheral osteoma - a benign osteogenic neoplasia. These tumours are cryptic in clinical expression, though they may present localised discomfort and swelling. It has been suggested that muscle traction may play a role in the development and expression of these tumours. The impact of this lesion on the individual affected is unknown. This study adds to the growing corpus of palaeopathological data from the South African fossil record, which suggests that the incidence of neoplastic disease in deep prehistory was more prevalent than traditionally accepted. The study also highlights the utility of micro-computed tomography in assisting accurate diagnoses of ancient pathologies.

Successful treatment of infertility in a female Sumatran orangutan Pongo abelii.

In 2011, a female Sumatran orangutan housed at Durrell Wildlife Conservation Trust became infertile following a massive antepartum hemorrhage in labor and the delivery of a stillborn infant. The placenta was infected with Pantoea sp. Hysterosalpingography (HSG) revealed blocked fallopian tubes, and pressurized fallopian tube perfusion was used to reverse the tubal occlusion. She subsequently conceived and following an intensive training program, we were able to measure umbilical artery waveform analysis for fetal well-being and placental localization to exclude placenta previa, which could complicate pregnancy and lead to catastrophic hemorrhage. The female went on to deliver a healthy offspring. We suggest that these techniques should be considered for other infertile females in the global captive population.

[Recurrent periods of respiratory tract infections in a 22-year-old].

A 22-year-old male with recurrent periods of coughing and nasal discharge was unable to work and cooperate. A bronchoscopy revealed high amounts of leucocytes and no eosinofils, acute inflammation and > 105/ml Streptococcus pneumoniae susceptible to penicillin. The symptoms relapsed after penicillin and at the age of 24 the patient was CT-scanned which revealed bilateral sinusitis, mastoiditis and bronchiectasis. Treatment with azithromycin and a weight loss programme (from 156 kg) improved the health of the patient, who was an orangutan. This highlights the benefit of cooperation between medical doctors and veterinarians.

Intestinal schistosomiasis in chimpanzees on Ngamba Island, Uganda: observations on liver fibrosis, schistosome genetic diversity and praziquantel treatment.

Despite treatment with praziquantel (PZQ) at 40 mg/kg in food, several chimpanzees on Ngamba Island Chimpanzee Sanctuary (NICS) continue to excrete eggs of Schistosoma mansoni. To monitor disease, 8 animals were closely examined under anaesthesia in March 2011 with portable ultrasonography and by rectal snip biopsy. Schistosome genetic diversity had been previously assayed within 4 of these chimpanzees, finding extensive diversity with 27 DNA barcodes encountered, although none was common to all animals. Calcified schistosome eggs were found in the rectal snips from 5 chimpanzees and liver fibrosis was clearly documented, indicative of progressive disease in 6 animals, the latter being surprisingly advanced in a younger chimpanzee. All 8 animals were treated under anaesthesia by oral gavage with PZQ at 60 mg/kg dosing that was well tolerated. These animals were again re-examined in June 2012 using stool and urine sampling. Only 1 chimpanzee appeared to be free from infection and active egg excretion was confirmed in 6 animals. If intestinal schistosomiasis is to be controlled within this setting, a long-term disease management plan is required which should combine active case-detection with an insistent treatment regime with praziquantel for these chimpanzees, exploring perhaps the performance of even higher dosing.

Use of an implantable loop recorder in the investigation of arrhythmias in adult captive chimpanzees (Pan troglodytes).

Cardiovascular disease in general, and cardiac arrhythmias specifically, is common in great apes. However, the clinical significance of arrhythmias detected on short-duration electrocardiograms is often unclear. Here we describe the use of an implantable loop recorder to evaluate cardiac rhythms in 4 unanesthetized adult chimpanzees (Pan troglodytes), 1 with a history of possible syncope and 3 with the diagnosis of multiform ventricular ectopy (ventricular premature complexes) and cardiomyopathy. The clinical significance of ventricular ectopy was defined further by using the implantable loop recorder. Arrhythmia was ruled out as a cause of collapse in the chimpanzee that presented with possible syncope because the implantable loop recorder demonstrated normal sinus rhythm during a so-called syncopal event. This description is the first report of the use of an implantable loop recorder to diagnose cardiac arrhythmias in an unanesthetized great ape species.

Diagnosis and treatment of degenerative joint disease in a captive male chimpanzee (Pan troglodytes).

Degenerative joint disease (DJD), also known as osteoarthritis, has been well documented in aging populations of captive and free-ranging macaques; however, successful treatments for DJD in nonhuman primates have not been published. Published data on chimpanzees show little to no DJD present in the wild, and there are no published reports of DJD in captive chimpanzees. We report here the first documented case of DJD of both the right and left femorotibial joints in a captive male chimpanzee. Progression from minimal to moderate to severe osteoarthritis occurred in this animal over the course of 1 y. Treatment with chondroprotective supplements (that is, glucosamine chondroitin, polysulfated glycosaminoglycan) and intraarticular corticosteroid injections (that is, methylprednisolone, ketorolac), together with pain management (that is, celecoxib, tramadol, carprofen), resulted in increased activity levels and decreased clinical signs of disease. DJD has a considerable negative effect on quality of life among the human geriatric population and therefore is likely to be one of the most significant diseases that will affect the increasingly aged captive chimpanzee population. As this case study demonstrates, appropriate treatment can improve and extend quality of life dramatically in these animals. However, in cases of severe osteoarthritis cases, medication alone may be insufficient to increase stability, and surgical options should be explored.

Lumbar diskectomy in a human-habituated mountain gorilla (Gorilla beringei beringei).

The authors report a case of a human-habituated mountain gorilla, Alvila, resident at the San Diego Zoo, who was found to have a herniated intervertebral lumbar disc after being attacked by the gorilla troop's silverback male gorilla. Ultimately, the gorilla required surgical intervention for her disease and made a full recovery. To our knowledge, this is the only known case of spine surgery. A 36-year-old female human-habituated mountain gorilla (Gorilla beringei beringei), resident at the San Diego Zoo, was noticed by caregivers to walk with a substantial limp after being attacked by the gorilla troop's silverback male gorilla. Magnetic resonance (MR) imaging of her lumbar spine revealed a large herniated disk at the L1-2 level on the right. This finding appeared to correlate well with the gorilla's symptoms. The gorilla underwent a lumbar diskectomy under loupe. Post-operatively the gorilla did very well. The right leg weakness was immediately improved post-operatively. The gorilla continued to "crutch walk" initially, swinging on the upper extremities and not bearing weight on the lowers. However, by 2 weeks the limp was no longer noticeable to the zoo caregivers. The wound healed well and there was no evidence of wound infection or CSF leak. The gorilla was reunited with her troop and has reintegrated well socially. With 10 months of follow-up, the gorilla continues to do well. This is the only known case of spine surgery in a gorilla. For best surgical results, one needs to consider the similarities and differences between the gorilla and human vertebral anatomy. We believe that careful pre-operative planning contributed to the good early post-operative result. Ultimate assessment of the long-term outcome will require additional follow-up.

Scoliosis in an Orangutan.

STUDY DESIGN: The first case of scoliosis in an Orangutan spine is reported. OBJECTIVES: To study the nature of scoliosis in the spinal specimen, and to determine the etiologic significance to human idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Idiopathic scoliosis has not been observed in primates other than man. Previous studies highlighted the importance of erect posture in the development of idiopathic scoliosis in man. METHODS: A spinal model of an orangutan spine was studied in great detail to determine its nature. The methods used included plain radiographs, computed tomography scans, a three-dimensional plastic model using rapid prototyping, and dissection of the frozen specimen. RESULTS: Features similar to human idiopathic scoliosis were noted including a right-side curve, vertebral rotation to convexity, displacement of the spinal cord to the concavity, and an equal number of ribs on either side. No evidence of congenital anomaly was found. Atypical findings included male gender, a short curve, and kyphosis at the apex. CONCLUSIONS: Although scoliosis found in the orangutan has features similar to idiopathic scoliosis, there also are some dissimilar features, making this diagnosis unlikely. The features observed in this spine suggest that erect posture is important in the morphology of human idiopathic scoliosis.

Surgical repair of an atrial septal defect in a juvenile Sumatran orangutan (Pongo pygmaeus sumatraensis).

A systolic heart murmur was auscultated in a 2-yr-old female Sumatran orangutan (Pongo pygmaeus sumatraensis) with a slower than expected growth rate. Cardiac ultrasound revealed an 11-mm atrial septal defect. Cardiac catheterization confirmed the diagnosis. Surgical repair was performed during cardiopulmonary bypass using a pericardial patch. The bypass pump was primed with human albumin and donor orangutan whole blood of a compatible type. Hematuria occurred shortly after the initiation of cardiopulmonary bypass. Successful repair was immediately confirmed with transesophageal ultrasonography. The animal was extubated shortly after returning to spontaneous ventilation but had to be reintubated 4 hr later due to tachypnea and decreased SpO2. Additional extubation attempts failed, necessitating continuous positive pressure ventilation, monitoring, and intensive care environment. Thoracic radiographs suggested adult respiratory distress syndrome. The animal required 14 days of intensive care before extubation of the trachea was successful. After 4 wk of isolation, the orangutan was successfully reintroduced to its family group.