Etude de la prévalence des infections à trypanosomes chez différentes espèces d'animaux sauvages du parc national de la Comoé en Côte d'Ivoire : résultats préliminaires sur la comparaison de trois méthodes de diagnostic

Si de nombreuses études portent sur la trypanosomoses chez les animaux domestiques, peu de rcherches ont été effectuées sur la faune sauvage d'Afrique occidentale. Les résultats préliminaires sur la comparaison de trois méthodes de dépistages des trypanosomes : le frottis de sang, la détection des antigènes circulants par le technique ELISA et l'isolement in vitro des trypanosomes par le "kit for in vitro isolation" (KIVI), chez les animaux sauvages du parc national de la Comoé en Côte d'ivoire, ont permis de confirmer l'existence de cette infection chez ces animaux sans toutefois identifier de façon précise les espèces de trypanosomes en cause. Des investigations ultérieures permettront d'affiner l'identification des souches de parasites isolées par KIVI. (Résumé d'auteur

Ulcerative pododermatitis in free-ranging African elephant (Loxodonta africana) in the Kruger National Park

The occurrence of severe lameness in adult African elephant bulls in a shrub Mopane (Colophospermum mopane) ecosystem was investigated. Large ulcers in the soles of at least one front foot were seen in each of the recorded cases. Microscopically, the lesion can be described as a severe, chronic-active, ulcerative, bacterial pododermatitis (complicated by hypersensitivity/septic vasculitis). A variety of bacteria were isolated from these lesions as well as from regional lymph nodes. Streptococcus agalactiae was the most consistent isolate, while Dichelobacter nodosus, the only organism known to be involved with foot disease in domestic ruminants, was isolated from two cases. Contributory factors such as body mass, portal of entry and origin of potential pathogens may have predisposed to the development of the lesions.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

An outbreak of encephalomyocarditis-virus infection in free-ranging African elephants in the Kruger National Park

A cluster of four deaths in late December 1993, marked the onset of an outbreak of disease of African elephants (Loxodonta africana) in the Kruger National Park (KNP) in South Africa, which has an estimated population of 7 500 elephants. Mortalities peaked in January 1994, with 32 deaths, and then declined steadily to reach pre-outbreak levels by September, but sporadic losses continued until November. During the outbreak altogether 64 elephants died, of which 53 (83%) were adult bulls. Archival records revealed that, in addition to the usual losses from known causes such as poaching and intraspecific fighting, sporadic deaths from unexplained causes had, in fact, occurred in widely scattered locations from at least 1987 onwards, and from that time until the perceived outbreak of disease there had been 48 such deaths involving 33 (69%) adult bulls. Carcases had frequently become decomposed or had been scavenged by the time they were found, but seven of eight elephants examined early in 1994 had lesions of cardiac failure suggestive of encephalomyocarditis (EMC)-virus infection, and the virus was isolated from the heart muscles of three fresh carcases. The results of tests for neutralizing antibody on 362 elephant sera collected for unrelated purposes from 1984 onwards and kept frozen, indicated that the virus had been present in the KNP since at least 1987. Antibody prevalences of 62 of 116 (53 %), 18 of 139 (13%) and seven of 33 (21 %) were found in elephants in three different regions of the KNP in 1993 and 1994. Studies had been conducted on myomorph rodents in the KNP for unrelated purposes since 1984, and trapping attempts were increased during the perceived outbreak of disease in elephants. There was a striking temporal correlation between the occurrence of a population explosion (as evidenced by markedly increased catch rates per trap-night) and a surge in prevalence of antibody to EMC virus in rodents, and the occurrence of the outbreak of disease in elephants.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Effect of Weld Schedule on the Residual Stress Distribution of Boron Steel Spot Welds

Press-hardened boron steel has been utilized in anti-intrusion systems in automobiles, providing high strength and weight-saving potential through gage reduction. Boron steel spot welds exhibit a soft heat-affected zone which is surrounded by a hard nugget and outlying base material. This soft zone reduces the strength of the weld and makes it susceptible to failure. Additionally, different welding regimes lead to significantly different hardness distributions, making failure prediction difficult. Boron steel sheets, welded with fixed and adaptive schedules, were characterized. These are the first experimentally determined residual stress distributions for boron steel resistance spot welds which have been reported. Residual strains were measured using neutron diffraction, and the hardness distributions were measured on the same welds. Additionally, similar measurements were performed on spot welded DP600 steel as a reference material. A correspondence between residual stress and hardness profiles was observed for all welds. A significant difference in material properties was observed between the fixed schedule and adaptively welded boron steel samples, which could potentially lead to a difference in failure loads between the two boron steel welds

Characterization of Loading Responses and Failure Loci of a Boron Steel Spot Weld

Boron steel, classed as an ultra high-strength steel (UHSS), has been utilized in anti-intrusion systems in automobiles, providing high strength and weight-saving potential through gage reduction. UHSS spot welds exhibit unique hardness distributions, with a hard nugget and outlying base material, but with a soft heat-affected zone in-between these regions. This soft zone reduces the strength of the weld and makes it susceptible to failure. Due to the interaction of various weld zones that occurs during loading, there is a need to characterize the loading response of the weld for accurate failure predictions. The loading response of certain weld zones, as well as failure loci, was obtained through physical simulation of the welding process. The results showed a significant difference in mechanical behavior through the weld length. An important result is that instrumented indentation was shown to be a valid, quantitative method for verifying the accuracy with which weld microstructure has been recreated with regard to the target weld microstructure

Transport and boma management techniques for black rhinoceros <i>Diceros bicomis</i> as used in the Etosha/Vaalbos operation

Selected Papers from the Rhinoceros Conservation Workshop, Skukuza, Kruger National Park,31 August – 4 September 1988 The translocation of six black rhinoceros from the Etosha National Park (Namibia) to the Vaalbos National Park (Republic of South Africa) is described. Data are provided on the transporting vehicle, the capture, transport and off-loading procedures followed while aspects of boma management are briefly dealt with

Evaluation of etorphine and midazolam anesthesia, and the effect of intravenous butorphanol on cardiopulmonary parameters in game-ranched white rhinoceroses (ceratotherium simum)

Nineteen white rhinoceroses ( Ceratotherium simum ) were anesthetized with 4 mg of etorphine hydrochloride; 35-40 mg of midazolam; and 7,500 international units of hyaluronidase for dehorning purposes at a game ranch in South Africa, to investigate this anesthetic combination. Median time to recumbency was 548 sec (range 361-787 sec). Good muscle relaxation and no muscle rigidity or tremors were observed in 18 animals, and only 1 individual showed slight tremors. In addition, all animals received butorphanol i.v. 5 min after recumbency at the ratio of 10 mg of butorphanol per 1 mg of etorphine. Blood gas and selected physiologic parameters were measured in the recumbent animal, immediately before and 10 min after the administration of butorphanol. Statistically significant improvements were observed in blood gas physiologic and cardiopulmonary parameters 10 min after the administration of butorphanol, with a reduction in arterial partial pressure of carbon dioxide, systolic blood pressure, and heart rate and an increase in pH, arterial partial pressure of oxygen, oxygen saturation, and respiratory rate (all P < 0.005). After i.v. naltrexone reversal, recovery was uneventful, and median time to walking or running was 110 sec (range 71-247 sec). The results indicate etorphine and midazolam combination is an effective alternative anesthetic protocol and produces good muscle relaxation. Furthermore, i.v. butorphanol was associated with improved blood gas values and cardiopulmonary function for at least 10 min postinjection.Martine van Zijll Langhout, Charles G.B. Caraguel, Jacobus P. Raath and Wayne S. J. Boardma

Immobilization quality and cardiopulmonary effects of etorphine alone compared with etorphine–azaperone in blesbok (Damaliscus pygargus phillipsi)

Objective To evaluate the immobilization quality and cardiopulmonary effects of etorphine alone compared with etorphine–azaperone in blesbok (Damaliscus pygargus phillipsi). Study design Blinded, randomized, crossover design. Animals A total of 12 boma-habituated female blesbok weighing [mean ± standard deviation (SD)] 57.5 ± 2.5 kg. Methods Each animal was administered etorphine (0.09 mg kg–1) or etorphine–azaperone (0.09 mg kg–1; 0.35 mg kg–1) intramuscularly with 1-week intertreatment washout period. Time to first sign of altered state of consciousness and immobilization time were recorded. Physiological variables were recorded, arterial blood samples were taken during a 40-minute immobilization period, and naltrexone (mean ± SD: 1.83 ± 0.06 mg kg–1) was intravenously administered. Recovery times were documented, and induction, immobilization and recovery were subjectively scored. Statistical analyses were performed; p < 0.05 was significant. Results No difference was observed in time to first sign, immobilization time and recovery times between treatments. Time to head up was longer with etorphine–azaperone (0.5 ± 0.2 versus 0.4 ± 0.2 minutes; p = 0.015). Etorphine caused higher arterial blood pressures (mean: 131 ± 17 versus 110 ± 11 mmHg, p < 0.0001), pH, rectal temperature and arterial oxygen partial pressure (59.2 ± 7.7 versus 42.2 ± 9.8 mmHg), but lower heart (p = 0.002) and respiratory rates (p = 0.01). Etorphine–azaperone combination led to greater impairment of ventilatory function, with higher end-tidal carbon dioxide (p < 0.0001) and arterial partial pressure of carbon dioxide (58.0 ± 4.5 versus 48.1 ± 5.1 mmHg). Immobilization quality was greater with etorphine-azaperone than with etorphine alone (median scores: 4 versus 3; p < 0.0001). Conclusions and clinical relevance Both treatments provided satisfactory immobilization of blesbok; however, in addition to a deeper level of immobilization, etorphine–azaperone caused greater ventilatory impairment. Oxygen supplementation is recommended with both treatments

Do potent immobilising-opioids induce different physiological effects in impala and blesbok?

Potent opioids are known to cause negative alterations to the physiology of immobilised antelope. How these effects differ between species has not been studied. This study aimed to compare time to recumbence and effects of opioid-based immobilisation on the physiology of impala (Aepyceros melampus) and blesbok (Damaliscus pygargus phillipsi). Eight animals of each species were immobilised, with 0.09 mg/kg etorphine and 0.09 mg/kg thiafentanil respectively, in a randomised two-way cross-over study. Variables measured and analysed by means of a linear mixed model included time to recumbence, heart rate, respiratory rate, arterial blood pressure, blood gases, lactate and glucose. In blesbok, mean time to recumbence was not significantly different with either drug (2.5 minutes and 2.2 min, respectively), but in impala thiafentanil achieved a shorter time to recumbence (2.0 min) than etorphine (3.9 min). Mean heart rates of immobilised impala were within reported physiological limits, but lower in immobilised blesbok when both opioids were used (35 beats/min to 44 beats/min vs. 104 ± 1.4 beats/min resting heart rate). Impala developed severe respiratory compromise and hypoxaemia from both opioids (overall mean PaO2 values ranged from 38 mmHg to 59 mmHg over 30 min). In contrast, blesbok developed only moderate compromise. Therefore, significantly different species-specific physiological responses to potent opioid drugs exist in blesbok and impala. Given that these different responses are clinically relevant, extrapolation of immobilising drug effects from one species of African ungulate to another is not recommended