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1.
Idiopathic hemorrhagic vasculopathy syndrome (IHVS) was diagnosed in 7 black rhinoceros; this newly described syndrome is characterized by severe body swelling in conjunction with a rapid and profound decrease in Hct. The disorder may be acute or chronic, may recur, and is potentially fatal. Five of the rhinoceros survived an initial episode of IHVS, and 2 of these 5 survived a recurrent episode of IHVS. Two rhinoceros died during treatment of IHVS. Treatment protocols varied, but all 7 rhinoceros received broad-spectrum antibiotics, because an infectious cause was suspected. All rhinoceros also received nonsteroidal antiinflammatory drugs and supportive care. Idiopathic hemorrhagic vasculopathy syndrome has many similarities to other vasculopathies of domestic animals, such as equine purpura hemorrhagica, but it also appears to have unique identifying features. It has been hypothesized that IHVS may be an immune response to an as yet unidentified infectious agent. Thorough and extensive testing has not identified the potential causative agent, nor the factors that predispose some black rhinoceros to developing IHVS. Further research into the rhinoceros immune system is ongoing and should help elucidate the mechanisms through which IHVS develops.  相似文献   

2.
The domestic horse is used as a nutritional model for rhinoceros maintained under human care. The validity of this model for browsing rhinoceros has been questioned due to high prevalence of iron overload disorder (IOD) in captive black rhinoceros (Diceros bicornis), which is associated with high morbidity and mortality. Iron chelators, such as tannins, are under investigation as dietary supplements to ameliorate or prevent IOD in prone species. Polyphenolic compounds variably affect microbial fermentation, so the first objective of this experiment was to evaluate the effects of grape seed extract (GSE; a concentrated source of condensed tannins; CT) on black rhinoceros hindgut fermentation. Equine nutrition knowledge is used to assess supplements for rhinoceros; therefore, the second objective was to evaluate the domestic horse model for black rhinoceros fermentation and compare fermentation responses to GSE using a continuous single‐flow in vitro culture system. Two replicated continuous culture experiments were conducted using horse and black rhinoceros faeces as inoculum sources comparing four diets with increasing GSE inclusion (0.0%, 1.3%, 2.7% and 4.0% of diet dry matter). Diet and GSE polyphenolic compositions were determined, and sodium sulphite effect on neutral detergent fibre extraction of CT‐containing forages was tested. Increasing GSE inclusion stimulated microbial growth and fermentation, and proportionally increased diet CT concentration and iron‐binding capacity. Horse and black rhinoceros hindgut microflora nutrient digestibility and fermentation responses to GSE did not differ, and results supported equine fermentation as an adequate model for microbial fermentation in the black rhinoceros. Interpretation of these results is limited to hindgut fermentation and further research is needed to compare foregut digestibility and nutrient absorption between these two species. Supplementation of GSE in black rhinoceros diets up to 4% is unlikely to adversely affect hindgut nutrient digestibility or microbial viability and fermentation.  相似文献   

3.
Captive African black rhinoceroses (Diceros bicornis) are unusually susceptible to several diseases not commonly observed in any of the other three rhinoceros species maintained in captivity. The potential role of corticosteroids (either endogenously produced or exogenously administered) in the development of these sometimes fatal diseases has been questioned. In this study, the suppressive effects of two therapeutic corticosteroids (dexamethasone and hydrocortisone) on in vitro lymphocyte proliferation was examined in four rhinoceros species, including the Sumatran rhinoceros (Dicerorhinus sumatrensis, n = 3), Indian rhinoceros (Rhinoceros unicornis, n = 4), African black rhinoceros (n = 10), and African white rhinoceros (Ceratotherium simum, n = 5). Three blood samples collected from each rhinoceros 1 mo to 1 yr apart provided replicates for the study. Both dexamethasone and hydrocortisone suppressed (P < 0.05) lymphocyte proliferation stimulated by B-cell mitogens (pokeweed and lipopolysaccharide) and T-cell mitogens (phytohemagglutinin and concanavalin A). Suppressive effects of the glucocorticoids differed (P < 0.05) depending on the mitogen used to stimulate the lymphocytes. Overall, dexamethasone was a more potent suppressor of cell proliferation when compared with hydrocortisone (P < 0.05). However, black rhinoceros cell proliferation in response to any of the four mitogens was never completely suppressed, even in cultures containing the highest steroid concentration tested (10(-3) M). The effect of the two corticosteroids differed slightly among the rhinoceros species and subspecies tested, but there was no evidence that eastern or southern black rhinoceros lymphocytes were more sensitive to the suppressive effects of corticosteroids than the other rhinoceros species.  相似文献   

4.
In South Africa, the black rhinoceros (Diceros bicornis) is divided into two subspecies, the South-western in the west and the South-central in the east. The exact boundary between the ranges of these subspecies is uncertain, but has been defined to coincide with the administrative border between the Northern Cape and North West provinces. It is current practice to refer to the South-central black rhinoceros as Diceros bicornis minor, which has Zululand as the type-locality. This needs adjustment, because an earlier valid scientific name was given to a rhinoceros killed near Zeerust in the western part of North West province. In line with the rules of zoological nomenclature, the South-central black rhinoceros should be known as Diceros bicornis keitloa.  相似文献   

5.
To investigate the syndrome of acute intravascular hemolytic anemia in the black rhinoceros (Diceros bicornis), laboratory techniques used in the differential diagnosis of hemolytic anemias were performed on blood samples from 6 black rhinoceroses: 3 nonrelated healthy rhinoceroses, 1 rhinoceros with iron deficiency anemia, and 2 rhinoceroses with intravascular hemolysis. Osmotic fragility, erythrocyte membrane protein composition, hemoglobin electrophoresis, and hemoglobin stability did not distinguish between healthy and affected (anemia or hemolysis) rhinoceroses. Polyclonal antiglobulin reagents were prepared in rabbits, using whole rhinoceros serum and purified rhinoceros immunoglobulin G. These reagents were nonreactive against erythrocytes of the healthy and iron-deficient rhinoceroses. Reactions with RBC from the rhinoceros with fatal hemolytic anemia indicated increased membrane coating by the third component of complement; this was not evident in a second rhinoceros that survived a hemolytic event.  相似文献   

6.
Cellular immune function in four rhinoceros species was evaluated by way of in vitro lymphocyte proliferation responses to mitogenic and antigenic stimuli to establish normative data on white blood cell activity for each species and to identify species-specific differences that might help explain the predisposition of black rhinoceroses (Diceros bicornis) to disease. A cross section of the U.S. rhinoceros population encompassing all four captive species was sampled, including the Sumatran rhinoceros (Dicerorhinus sumatrensis) (n = 3); Indian rhinoceros (Rhinoceros unicornis) (n = 4); African black rhinoceros (n = 16); and African white rhinoceros (Ceratotherium simum) (n = 10). Of the four species evaluated, African black rhinoceroses exhibited the weakest (P < 0.05) lymphocyte proliferative responses to the mitogens: pokeweed (0.1 microg/ml), phytohemagglutinin (0.3 microg/ml), and concanavalin A (5.0 microg/ml). Total cell density at the end of culture was only 70% of that achieved with lymphocytes isolated from African white rhinoceroses, Indian rhinoceroses, and Sumatran rhinoceroses. However, lymphocyte response to bacterial endotoxin lipopolysaccharide was similar (P > 0.05) across species. Antigenic stimulation produced much weaker responses than mitogenic stimulation. No differences (P > 0.05) were observed among rhinoceros species in response to 1 and 10 microg/ml of Leptospira icterohemorrhagiae or Leptospira gryppotyphosa. Lymphocytes from African white rhinoceroses proliferated weakly in the presence of Aspergillus fumigatus filtrate, whereas lymphocytes from the southern black rhinoceros subspecies appeared slightly suppressed in the presence of increasing doses (0.1, 1, and 10 microg/ml) of Aspergillus filtrate. This comparative data set characterizing lymphocyte proliferation in the rhinoceros reveals several differences in immune cell responses among rhinoceros species and provides some evidence that lymphocytes of captive African black rhinoceroses are less vigorous than those of the other rhinoceros species.  相似文献   

7.
A 21-mo-old female southern black rhinoceros (Diceros bicornis minor) developed acute upper respiratory dyspnea in association with lymphadenopathy and marked immature lymphocytosis. A diagnosis of acute lymphoblastic leukemia was reached on the basis of the morphologic and cytochemical characteristics of peripheral lymphoblasts. Antineoplastic chemotherapy included administration of cytarabine, cyclophosphamide, vincristine, and doxorubicin, with clinical remission achieved 19 days after initiation of treatment. The rhinoceros died, however, of congestive heart failure, presumably secondary to doxorubicin cardiotoxicity and a particular sensitivity of rhinoceros myocardial tissue to free hydroxyl radicals. The pharmacologic effects of any therapeutic agent need to be carefully considered before use in the black rhinoceros, especially within the context of the unique physiology of this species.  相似文献   

8.
A testicular mass was identified by ultrasonography performed during a routine reproductive evaluation of an adult male southern black rhinoceros ( Diceros bicornis minor ). Histological examination of a testicular biopsy supported a presumptive diagnosis of testicular neoplasia. Hemi-castration was performed to excise the affected testis and a pathological diagnosis of a seminoma was made. Assessment of semen suggested reduced fertility as a consequence of the neoplastic process, but hemi-castration prevented further growth and metastasis of the tumour and ensured the animal's breeding potential. This is the second documented case of a seminoma in a rhinoceros species and the first case in a black rhinoceros.  相似文献   

9.
The oedematous and traumatised protruding section of the rectal tissue of an adult free-ranging female African black rhinoceros (Diceros bicornis) was surgically amputated. Immediately before completion of surgery, the rhinoceros died of anaesthetic-related cardiac arrest. At necropsy a deformed pelvis and sacrum associated with a healed fracture of the left ileal wing were noted. New bone formation in and around the left ventral sacral foramina may have resulted in neuropathy of particularly the 3rd and 4th left ventral sacral nerves, which (in the horse) supply the majority of the nerve fibres innervating the caudal rectum and anus. The cause of the injury is not known, although back injuries, presumably sustained during mating by bulls, have been recorded in white rhinoceros. An encounter with elephants could also have been responsible for the injury in this case.  相似文献   

10.
Bovine tuberculosis (BTB) is endemic in African buffalo (Syncerus caffer) in the Kruger National Park (KNP). In addition to buffalo, Mycobacterium bovis has been found in at least 14 other mammalian species in South Africa, including kudu (Tragelaphus strepsiceros), Chacma baboon (Papio ursinus) and lion (Panthera leo). This has raised concern about the spillover into other potentially susceptible species like rhinoceros, thus jeopardising breeding and relocation projects aiming at the conservation of biodiversity. Hence, procedures to screen for and diagnose BTB in black rhinoceros (Diceros bicornis) and white rhinoceros (Ceratotherium simum) need to be in place. The Interferon-gamma (IFN-gamma) assay is used as a routine diagnostic tool to determine infection of cattle and recently African buffalo, with M. bovis and other mycobacteria. The aim of the present work was to develop reagents to set up a rhinoceros IFN-gamma (RhIFN-gamma) assay. The white rhinoceros IFN-gamma gene was cloned, sequenced and expressed as a mature protein. Amino acid (aa) sequence analysis revealed that RhIFN-gamma shares a homology of 90% with equine IFN-gamma. Monoclonal antibodies, as well as polyclonal chicken antibodies (Yolk Immunoglobulin-IgY) with specificity for recombinant RhIFN-gamma were produced. Using the monoclonals as capture antibodies and the polyclonal IgY for detection, it was shown that recombinant as well as native white rhinoceros IFN-gamma was recognised. This preliminary IFN-gamma enzyme-linked immunosorbent assay (ELISA), has the potential to be developed into a diagnostic assay for M. bovis infection in rhinoceros.  相似文献   

11.
Two black rhinoceroses (Diceros bicornis michaeli) developed clinical leptospirosis without hemolytic crises. The first rhinoceros presented with peracute depression, anorexia, rear leg trembling, dysuria, glucosuria, gastrointestinal discomfort, and decreased fecal output and died within 12 hr. Necropsy and histopathology revealed lesions within multiple organs. Leptospirosis was diagnosed postmortem based on positive fluorescent antibody staining of liver. The second rhinoceros presented 2 mo later with similar signs. It survived with treatment and was diagnosed with leptospirosis based on serology using microscopic agglutination testing and detection of urinary antigen using a fluorescent antibody technique. Leptospira kirschneri serovar grippotyphosa was postulated as the etiologic agent, with transmission probably occurring through wallow contamination by wild raccoons (Procyon lotor).  相似文献   

12.
OBJECTIVES: To measure metabolic rates of the hexose monophosphate shunt (HMPS) in erythrocytes of rhinoceroses, and to test the hypothesis that low concentrations of endogenous ATP in erythrocytes impair HMPS capacity, thereby increasing susceptibility to oxidant-induced hemolysis. ANIMALS: 13 black and 3 white rhinoceroses, free-ranging in several regions of southern Africa, and 1 Sumatran rhinoceros in US captivity. PROCEDURE: HMPS fluxes were measured in rhinoceros erythrocytes with carbon-labeled glucose in the presence and absence of known HMPS activators. RESULTS: Compared with values for human erythrocytes, mean basal state HMPS fluxes were appreciably lower (22 to 46%) in all 3 rhinoceros species studied. Shunt activators increased HMPS rates approximately 5-fold over basal rates in rhinoceros erythrocytes, compared with increases in humans of 10-fold with ascorbate and 15-fold with methylene blue. Stimulated HMPS rates in human erythrocytes were quantitatively 5- to 10-times greater than those observed in rhinoceros erythrocytes. Overall HMPS catabolic rates were completely independent of intracellular ATP concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: HMPS glycolytic and recycling rates and responses to activators are inherently low in erythrocytes from 3 species of rhinoceros, likely contributing to (but not solely responsible for) the high susceptibility of black rhinoceroses to oxidant-induced hemolysis. Slow erythrocyte HMPS capacities were independent of intracellular ATP concentrations, invalidating a current hypothesis regarding the pathogenesis of hemolytic anemia in captive black rhinoceroses. Limitations in HMPS capacities emphasize the importance of protecting rhinoceroses from exposure to drugs, chemicals, toxins, foodstuffs, and other conditions known to increase production of oxidizing metabolites, reactive oxygen species, and free radicals.  相似文献   

13.
In contrast to the grazing white (C. simum) and Indian (R. unicornis) rhinoceros, the black rhinoceros (D. bicornis) is an exclusive browser. Due to the particular fermentation characteristics of browse, one would expect browsers to display both shorter ingesta retention times and lower digestion coefficients on comparable diets than grazers. In order to generate a database to test this hypothesis, we performed digestibility studies in eight black rhinoceroses (D. bicornis) from three zoological institutions, using total faecal collection for the quantification of faecal output. One to three regularly fed zoo rations of roughage, concentrates and varying proportions of browse material were used per animal. Additional data was taken from three hitherto unpublished studies as well as several published sources. When compared with horses on similar rations, black rhinoceroses achieved lower digestion coefficients for organic matter and CF. In general, an increase in dietary CF content led to a steeper decrease in organic matter and GE digestibility in black rhinoceroses than in horses. When comparing available data for rhinoceroses, browsing species showed a steeper decrease in organic matter digestibility than grazing species with increasing dietary cell wall content. Endogenous losses as determined by linear regression analysis were within the range reported for horses and Indian rhinoceroses. The results suggest that the horse is not a useful model animal for evaluating diets for black rhinoceroses energetically. In general, diets fed to captive black rhinoceroses seem to include higher proportions of concentrates than diets for other rhinoceros species, and an increase in browse or roughage would reduce digestion coefficients to levels observed in animals fed natural forage.  相似文献   

14.
Two weeks before dying of congestive heart failure, a juvenile black rhinoceros (Diceros bicornis minor) received a single low dose of doxorubicin as part of combination chemotherapy for acute lymphoblastic leukemia. Diffuse hemosiderosis was present at necropsy in a pattern indicative of dietary iron overload, but unique iron-positive degenerative lesions were found in isolated myocardiocytes. Serum analyses revealed hyperferremia, 87% transferrin saturation, and 5- to 10-fold elevations in ferritin concentration, reflecting markedly increased tissue iron stores. Since both toxic and therapeutic effects of anthracyclines are mediated by formation of reactive free radicals via iron-catalyzed reactions, these observations suggest that iron overload may have enhanced myocardial susceptibility to cardiotoxic effects of doxorubicin. Impairments in other myocardial antioxidant defenses, such as deficiencies in catalase and glutathione S-transferase that are known to exist in rhinoceros erythrocytes, may have been underlying factors contributing to an inherent sensitivity of rhinoceros tissues to oxidant-induced injury.  相似文献   

15.
An adult female southern black rhinoceros (Diceros bicornis minor) experienced intermittent periods of regurgitation while eating, suggesting an esophageal disorder. Endoscopy for evaluation of the trachea, esophagus, and stomach revealed a 30-mm nasopharyngeal orifice with associated recess located in the caudodorsal pharynx and a 10-cm dilated segment of the distal esophagus that was presumably the cause of regurgitation. Dietary management of esophageal dilation through short-term utilization of a "soft feed" program successfully eliminated the regurgitation. This is the first report of esophageal dysfunction in a rhinoceros.  相似文献   

16.
Reproductive tracts or tissues from five male black rhinoceroses (Diceros bicornis), two male white rhinoceroses (Ceratotherium simum), two male one-horned Asian rhinoceroses (Rhinoceros unicornis), seven female black rhinoceroses, and six female white rhinoceroses from multiple institutions were examined to characterize their anatomy and histology. Some observations and measurements were obtained from in situ tracts of intact animals before or during necropsy. Formalin-fixed tissues were dissected and examined histologically. Retrospective reproductive data from each rhinoceros was obtained from the institutions of origin. Reproductive histology of these species was similar to that of other mammals. Male accessory gland structure varied among species, and the Asian rhinoceros epididymis was more loosely attached and had larger duct diameters than did the epididymides of the African species. Although histology was typically mammalian, rhinoceros reproductive morphology combined characteristics of several different mammals. Defining this unique morphology of rhinoceroses may help in understanding their reproductive physiology and will effect the development of appropriate reproductive techniques.  相似文献   

17.
Flow cytometric sexing of spermatozoa followed by application in artificial insemination or in vitro fertilization provides a unique opportunity to predetermine the sex of offspring and might enhance the conservation management of endangered species in captivity such as the elephant and rhinoceros. To obtain an indication of the sortability of spermatozoa from these species, the relative DNA differences between X and Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from three rhinoceros species [white ( Ceratotherium simum ), black ( Diceros bicornis ), Indian ( Rhinoceros unicornis )] and both elephant species, the Asian and the African elephant ( Elephas maximus, Loxodonta Africana ), were determined through separation of spermatozoa into X and Y chromosome bearing populations, using a modified high speed flow cytometer. The head profile areas of spermatozoa from all five species were measured using light microscopy. By multiplying the relative DNA differences and the head profile areas, the sperm sorting indices were calculated to be 47, 48 and 51 for white, black and Indian rhinoceros respectively. The calculated sorting index for the Asian elephant was 66. In the African elephant, we determined the highest sorting index of 76. These results indicate the practicability of flow cytometric sex sorting of spermatozoa from the tested rhinoceros species and both elephant species. The lower sorting indices in rhinos indicate that sex sorting of spermatozoa from the rhinoceros will be more challenging than in elephants.  相似文献   

18.
The skew toward males in the sex ratio of calves is considered to be a problem for the captive population of black rhinoceroses (Diceros bicornis) in North America. This study used a retrospective case-control design to determine whether there was a predisposition toward birth of male calves over female calves and to examine risk factors associated with the occurrence of any detected skewed natal sex ratio in captive black rhinoceroses in the United States. The study population included captive female black rhinoceroses housed in the United States that had given birth to at least one calf of known sex. This study confirmed a skewing of the natal sex ratio toward male calves in the captive black rhinoceros population. The skewed ratio was found in calves born to wild-born dams, for which an increased time in captivity, irrespective of age, was associated with an increased likelihood of a male calf. Dams between 12 and 19 yr of age had a decreased likelihood of a male calf. The data also suggested a possible trend for the southern subspecies of black rhinoceros (Diceros bicornis minor) to be more likely to produce male calves than the eastern subspecies (Diceros bicornis michaeli). No associations were found with the sex of offspring in captive-born dams: however, this lack of association could be a result of low power in the study.  相似文献   

19.
Management of the endangered black rhinoceros (Diceros bicornis michaeli) in Africa frequently involves translocation. These procedures are not without risk, and protocols must be critically examined. Hematologic analyses can be used to evaluate the effects of translocation on animal health. Hematologic data obtained during routine translocation of free ranging black rhinoceros (n = 74) in Kenya between 1991 and 1995 were examined, and subsets of data from rhinoceros (n = 43) that were translocated to different regions of Kenya were compared. All animals showed an increase in total blood protein. Animals transported for longer periods and to lower altitude zones with higher ambient temperatures and trypanosomiasis developed anemia and showed neutrophilia, lymphopenia (males), and eosinopenia. The changes in packed cell volume (PCV), hemaglobin, and neutrophils were more marked in females, and the PCV drop was more significant in subadults. The red cell changes were most probably pathologic, involving the loss of red cells from circulation through sequestration or hemorrhage. The changes in white cell parameters are consistent with the effect of endogenous corticosteroids as a result of stress. Transport and confinement stress might lead to gastric ulceration with hemorrhage. In many animals, exposure to trypanosomes contributes to anemia.  相似文献   

20.
Control of body temperature is critical to a successful anesthetic outcome, particularly during field immobilization of wild animals. Hyperthermia associated with exertion can lead to serious and potentially life-threatening complications such as organ damage (including myopathy) and death. Methods for monitoring core body temperature must accurately reflect the physiologic status of the animal in order for interventions to be effective. The goal of this preliminary study was to compare serial rectal and muscle temperatures in field-immobilized black rhinoceros (Diceros bicornis) and evaluate a possible association. Twenty-four free-ranging black rhinoceros were immobilized between February and March of 2010 in Ethosha National Park, Namibia. Pairwise comparisons showed a correlation of 0.73 (95% CI; 0.70-0.75) between rectal and muscle temperature measurements. Results from a multivariable model indicate that muscle temperature readings were, on average, 0.46 degrees C (95% CI; 0.36-0.57 degrees C) higher than rectal temperatures while adjusting for repeated measurements on the same rhinoceros, effect of duration of immobilization, and effect of ambient temperature on rhinoceroses' temperature readings. As immobilization time increased, muscle and rectal temperature values within an individual rhinoceros tended to equilibrate. The overall temperatures decreased by an average of 0.00059 degrees C/min (95% CI; -0.0047 to -0.0035 degrees C/min; P = 0.779). As the ambient temperature at time of immobilization increased by 1 degree C, the average rhinoceros temperature increased by 0.09 degrees C (95% CI; 0.06-0.11 degrees C, P < 0.0001). Higher body temperature creates a potential for cellular damage leading to complications that include myopathy. Methods for monitoring rectal, muscle, and ambient temperatures should be incorporated into anesthetic monitoring protocols for large ungulates, particularly under field conditions.  相似文献   

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