Publications by authors named "Hendrik Nollens"

Respiratory rate (mean number of breaths per minute) and respiratory interval (mean time between breaths) can offer insight into a diving mammal's activity state, metabolic rate, behavior, and synchronization due to social cohesion. Also, respiratory rate can reflect an individual animal's health and has the potential to be an informative remotely assessed health metric for monitoring individual animal health in endangered whale species and populations such as southern resident killer whales (Orcinus orca). Using data collected from noninvasive, land-based theodolite tracking, we analyzed swimming speed and surfacing intervals (i.

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Polar bears () face a number of challenges that threaten the survival of the species. Captive breeding represents one essential facet of species conservation, but aspects of the polar bear's reproductive physiology, such as follicle maturation, coitus-induced ovulation, and pseudopregnancy, are poorly characterized and present challenges for enhancing natural reproductive success and the application of advanced reproductive techniques. Due to the absence of a reliable transrectal or transabdominal ultrasound method for ovarian examination in the species, the ovaries of two adult female polar bears were examined laparoscopically to evaluate the feasibility of surgical access to the ovaries, oviduct, and uterus.

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Photographic identification catalogs of individual killer whales (Orcinus orca) over time provide a tool for remote health assessment. We retrospectively examined digital photographs of Southern Resident killer whales in the Salish Sea to characterize skin changes and to determine if they could be an indicator of individual, pod, or population health. Using photographs collected from 2004 through 2016 from 18,697 individual whale sightings, we identified six lesions (cephalopod, erosions, gray patches, gray targets, orange on gray, and pinpoint black discoloration).

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Environmental enrichment devices (EEDs) have been proven to promote positive wellbeing in zoos and aquariums, and support animals' reintroduction success; however, their use in rehabilitation centers is still limited. This pilot study investigated the safety and efficacy of three EEDs, Artificial Kelp, Horse KONG and Wubba Kong, and their ability to decrease and/or eliminate undesired stereotypic behaviors or looking at staff/staff areas in seven wild California sea lions (CSLs) and eight northern elephant seals (NESs) undergoing rehabilitation in Southern California. Observers conducted instantaneous sampling once a minute during a 30-min baseline, followed by a 30-min EED implementation on one focal animal at a time.

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Neutrophils are one of the initial cell lines of protection against pathogens, and when their concentrations in the blood are low, animals are highly susceptible to infections. Neutropenia has been reported in cetaceans secondary to administration of systemic sulfa antibiotics or antifungal medications and severe, overwhelming infection. Filgrastim was administered to treat neutropenia over a 15-y period in 11 cetaceans comprising four species-beluga (, = 1), bottlenose dolphin (, = 4), killer whale (, = 5), and short-finned pilot whale (, = 1)] ranging in age from 1 wk to >24 y.

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Parapoxviruses cause nodular lesions on the skin and mucosal membranes of pinnipeds and infections by these viruses have been documented worldwide. Seal parapoxvirus is currently classified as a tentative species of the genus. Tissue or swab samples were analyzed from 11 pinnipeds of different host species undergoing rehabilitation on the east and west coasts of the United States of America (USA) that were positive for parapoxvirus.

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associated with neurobrucellosis, has been isolated from cerebrospinal fluid (CSF) of postmortem cetaceans. A 106-kg, stranded female bottlenose dolphin () presented with serum antibodies to spp. via competitive enzyme-linked immunosorbent assay and fluorescence polarization assay.

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Background: A comprehensive evaluation of the effects of sex, age, and season on blood analytes in a robust population size of bottlenose dolphins ( spp.) has not been investigated to date.

Aim: To define the variation in hematological and biochemical analytes of dolphins due to sex, age, and season.

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Dolphin tattoo lesions are superficial non-raised skin lesions caused by poxviruses. Their presentation can vary but typical lesions in bottlenose dolphins are circular to ovoid with concentric rings of black stippling. These lesions have at times been suggested as an indicator of overall dolphin health and welfare.

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The pharmacokinetics of danofloxacin was investigated in rehabilitated California brown pelicans () after a single intramuscular injection at a dose of 15 mg/kg body weight. The concentration of the drug in plasma was assayed by high-pressure liquid chromatography. A sparse-sampling design was used to reduce the number of samples (1-4 venipunctures) obtained from 24 brown pelicans.

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is a significant pathogen in zoological species, although information on environmental variables influencing fungal prevalence in zoological settings are lacking. The objective of the study was to estimate the prevalence of and to identify environmental factors associated with aerosolised spores at a zoological park to advance the understanding of fungal exposure as a first step towards improved mitigation strategies for susceptible animals. Twenty-one locations were sampled for presence of species using the SAS Super 180 Microbial Air Sampler, while twenty-two environmental factors were evaluated every two weeks at SeaWorld of California during two 12-month periods.

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For many reptile species, adequate ultraviolet B (UVB) radiation is essential for proper calcium metabolism. In this study, the effects of UVB radiation on calcium metabolism were evaluated in green sea turtles (). 25-Hydroxyvitamin D, parathyroid hormone (PTH), and ionized calcium (iCa) were measured in juvenile ( = 18, 9 indoor, 9 outdoor) and adult ( = 8, 4 indoor, 4 outdoor) turtles.

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Ill and anorectic captive sharks present a unique challenge for husbandry and veterinary staff. Providing adequate fluid and nutritional support to sharks while minimizing handling remains difficult. This study aimed to evaluate the ability of a nutrient enema to alter blood analyte concentrations.

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Background: The effects of sex, age, and season on blood analyte concentrations have not been investigated for the killer whale (Orcinus orca). Defining these changes provides background data for improving the care of managed populations and defines normal changes that could occur in wild counterparts.

Objectives: We aimed to define hematologic and serum biochemical variation by age, sex, and season for an ex situ killer whale population.

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Cobalamin and folate are water-soluble vitamins that are useful indicators of chronic gastrointestinal (GI) function in humans and some animal species. Serum cobalamin and folate concentrations in an ex situ population of killer whales ( Orcinus orca) were measured and factors that may affect their serum concentrations were identified. Serum samples ( n = 104) were analyzed from killer whales ( n = 10) both while clinically healthy and during periods of clinical GI disease as defined by clinical signs and fecal cytology.

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Relatively little is known about elasmobranch reproductive physiology compared to other species. An increased understanding of elasmobranch reproduction would improve the success of captive breeding and may aid in situ conservation efforts by reducing demand for wild-caught individuals. The reproductive status of seven adult female white-spotted bamboo sharks (Chiloscyllium plagiosum) (WSB) was monitored via coelomic ultrasonography and analysis of plasma biochemistry and steroid hormones over 6 months.

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Pulmonary disease has been well documented in wild and managed dolphin populations. The marginal lymph nodes of the dolphin thorax provide lymphatic drainage to the lungs and can indicate pulmonary disease. This study standardized a technique for rapid, efficient, and thorough ultrasonographic evaluation of the marginal lymph nodes in bottlenose dolphins ( Tursiops truncatus).

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A female, captive bred, juvenile swell shark ( Cephaloscyllium ventriosum ) was observed swimming in tight circles and rolling. Radiographs and computed tomography of this individual revealed extensive cartilage mineralization of the skull and cranial cervical vertebrae compared with diagnostic images of clinically healthy conspecifics. Gross necropsy and histopathologic examination revealed ossification and fibrosis of the cartilaginous matrix of the skull and cervical vertebrae with deep invasion by a pigmented hyphal fungus.

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Erysipelothrix rhusiopathiae is the causative agent of erysipeloid in humans and of erysipelas in various animals, including bottlenose dolphins Tursiops truncatus, in which an infection has the potential to cause peracute septicemia and death. The purpose of this study was to evaluate the efficacy of using an off-label porcine (ER BAC PLUS®, Zoetis) E. rhusiopathiae bactrin in a bottlenose dolphin vaccination program by determining the anti-E.

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Multiple black raised nodular masses were noted on the dorsal surface of an adult male Haller's round ray Urobatis halleri. Biopsy of 2 masses was performed, and histopathology revealed proliferative sheets of melanocytes exhibiting mild anisocytosis and anisokaryosis, supporting a diagnosis of malignant melanoma. Approximately 2 mo following the biopsy procedure, the round ray became acutely anorexic and was found dead in its enclosure.

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Research was performed to increase our understanding of male Magellanic penguin (Spheniscus magellanicus) reproductive biology and to develop artificial insemination (AI) technology to assist with maintaining the species' genetic diversity. Seminal traits were characterized from seven males with noncontaminated ejaculates (n = 123) displaying high in vitro motion parameters, membrane integrity, and morphology. Seven females were maintained in nest sites that permitted visual, auditory, and tactile contact with their paired male but not copulation for 18.

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The quantification of circulating plasma immunoglobulins represents a valuable diagnostic tool in human and veterinary immunology, although its application is very limited in reptile medicine to date. The objectives of our study were the development and standardization of a competitive enzyme-linked immunosorbent assay (cELISA) for the measurement of total plasma immunoglobulins (Igs; both IgM and IgY) in loggerhead sea turtles (LST; Caretta caretta; n = 254) and green turtles (GT; Chelonia mydas; n = 111), the establishment of reference intervals for Ig for both species, and the examination of associations between Ig and total protein (TP), condition index, and water temperature. The cELISA for Ig was successfully developed and optimized.

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Aspergillosis is a common respiratory fungal disease in penguins managed under human care. Triazole antifungal drugs, including itraconazole, are most commonly used for treatment; however, itraconazole treatment failures from drug resistance are becoming more common, requiring newer treatment options. Voriconazole, a newer triazole, is being used more often.

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Determining sex ratios of endangered populations is important for wildlife management, particularly species subject to sex-specific threats or that exhibit temperature-dependent sex determination. Sea turtle sex is determined by incubation temperature and individuals lack external sex-based traits until sexual maturity. Previous research utilized serum/plasma testosterone radioimmunoassays (RIA) to determine sex in immature/juvenile sea turtles.

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