Biographical sketch of Hendrik Jan Bertschinger

Biography of Hendrik Jan Bertschinger. The biography includes information about his education and career, scientific contributions and writings, homages and distinctions.Some personal information is erased from the original document for security reasons and to protect the person's identityab202

Fertility suppression of some wildlife species in southern Africa a review

Generally speaking, southern Africa's wildlife populations in small-to-medium-sized protected game reserves (10,000 65,000 ha) reproduce at rapid rates which often lead overpopulation of certain species. Most commonly these are large predators such as lions, African wild dogs and cheetahs, and elephants. Overpopulation of large predators leads to depletion of prey species, breakouts into neighbouring communities and increased risks for disease transmission. An overabundance of elephants leads to habitat destruction which is to the detriment of not only other herbivores but also certain bird species. By far, the most acceptable and effective method of population control is contraception. Another problem, particularly in South Africa, is the large numbers of large predators that are held in zoos, wildlife sanctuaries or captive breeding facilities. Once again, there is a need for contraception to control the rate of reproduction. In this review, we discuss the methods that have been most commonly used for some wildlife species in southern Africa. The methods include hormonal control and immunocontraception. We also address the problem of androgen-related aggressive behaviours in elephant bulls and giraffe males and present solutions that have been used to ameliorate such behaviours.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1439-05312017-09-30Production Animal Studie

Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine

Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5 -pregnan-3 -ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5 -pregnan-3 -ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5 -pregnan-3 -ol-20-on concentrations were 1.61 0.46 g/g (mean SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5 -pregnan-3 -ol-20-on concentrations. Average 5 -pregnan-3 -ol-20-on levels positively correlated with rainfall. No association between average individual 5 -pregnan-3 -ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post-treatment and onward. Results indicate the presence of ovarian activity amongst pZP-treated female African elephants in 2 yr after initial immunization. Further study should now be aimed toward investigating the long-term effects of pZP vaccination on the reproductive function of female African elephants.Thornybush Private Nature Reserve, the US Fish and Wildlife Service-African Elephant Conservation Fund, Humane Society International, and the University of Pretoria.http://www.theriojournal.comab201

Carcass utilization by tigers : implications for calculating prey requirements

Fewer than 3,500 tigers (Panthera tigris) remain in the wild. Habitat loss and fragmentation, and depletion of prey are key factors contributing to their decline, prompting investigations on prey requirements needed to sustain their dwindling populations. To estimate prey requirements from consumption rates the Non-Consumed Portion of a carcass (NCP) or degree of carcass utilization is required, as depending on prey size part of the kill might not be consumed. Because NCPs for tigers have never been systematically estimated, the aim of this study was to develop a model to calculate NCPs based on prey body mass, and to determine whether the NCPs used in current tiger literature were accurate. Additionally, we applied the model to two tiger reserves to test if our results improved prey requirement estimates calculated with current NCPs. The study took place at Laohu Valley Reserve (South Africa), where four male and five female tigers were fed fresh carcasses of six ungulate species. Each prey carcass was weighed prior to feeding to tigers and once abandoned, the remains were weighed allowing the weight consumed minus the gastrointestinal contents to be calculated. We observed a strong positive relationship between prey body mass and NCP. For large prey, prey requirement estimates obtained with the NCPs yielded by our model were very similar to those obtained with the NCPs used in current tiger literature. However, differences increased for smaller prey, and for those species that comprised a high percentage of the tiger diet. In summary, we provide a model to calculate NCPs based on prey body mass, and demonstrate the importance of using specific values of NCPs in calculating prey requirements from consumption rates. These results could be useful for other large carnivores, as well as for calculating feed portions for large predators in captive settings.We thank the University of Pretoria for partly funding the lead author in conducting this and other related studies of tigers, as well as Save China’s Tigers for providing funding for the lead author, the facilities, and logistic support for data collection.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1469-79982018-02-28hb2017Production Animal Studie

Porcine zona pellucida vaccine immunocontraception of African elephant (Loxodonta africana) cows : a review of 22 years of research

BACKGROUND : The native porcine zona pellucida (pZP) vaccine has been successfully used for immunocontraception of wild horses, white-tailed deer and approximately 90 zoo species for more than 25 years. OBJECTIVES : To provide proof of concept and test contraceptive efficacy of pZP in African elephants. Once completed, test the population and behavioural effects on cows in the Greater Makalali Private Game Reserve (GMPGR). Following the GMPGR, test efficacy, population effects, safety and reversibility in 25 reserves with populations ranging from 9 to 700 elephants. METHOD : Histological sections were reacted with anti-pZP antibodies to provide proof of concept. From 1996 to 2000, 21 and 10 cows were treated with pZP vaccine in the Kruger National Park (KNP) and monitored for pregnancy. Population effects of pZP with Freund’s adjuvants (three vaccinations in Year 1 with one annual booster) were studied on 18 cows in the GMPGR. Another six game reserves with a total of 90 cows were added to the project. The project was then expanded to include another 18 reserves. RESULTS : Binding of anti-pZP antibodies to elephant zona proteins was demonstrated in vitro. The KNP provided efficacy results of 56% and 80%, respectively. The contraceptive efficacy in the GMPGR and additional six reserves was 100% following calving of pregnant cows. Safety and lack of impact on social behaviour were demonstrated. In larger populations, efficacy was > 95%. CONCLUSION : Contraceptive efficacy and safety of pZP vaccine could be demonstrated in small to large populations. The methodology is now being implemented in approximately 800 cows on 26 reserves across South Arica.http://www.abcjournal.orgam2018Production Animal Studie

Immunocontraception of the female African savanna elephant (Loxodonta africana) in South Africa : from pipe dream to policy

Globally, African savanna elephants have been assessed as ‘endangered’. Consequently, additional threats and losses due to human–elephant conflict (HEC) could further exacerbate the species’ decline. In stark contrast, South Africa’s elephant populations are mostly confined within fenced-in reserves that impede natural processes such as migration. As ecosystem engineers, elephant population growth herein should be limited. Within South Africa, elephant management has evolved as differing wildlife philosophies from utilitarian conservation (‘nature for man’) to biocentric preservation (‘nature for nature’) and a combination thereof, have been practiced. Traditionally, both HEC and population control have been largely synonymous with lethal control, i.e. culling. However, with the increase of public or expert input to Policy, lethal control is not favoured by the public. As an alternative, immunocontraception of female African savanna elephants through non-invasive, native porcine zona pellucida (pZP) vaccinations has been employed successfully and is currently adopted in 43 elephant reserves across South Africa. Current legislation now recommends culling as the last population management resort. Newly promulgated legislation calls for wellbeing and welfare to be carefully measured in all biodiversity management decisions taken to minimise threats to biodiversity. As a keystone species, elephant is a direct driver of biodiversity change. Accordingly, and in light of these developments, all population management options, including immunocontraception, must be fully considered in South Africa’s largest national park, the Kruger.https://www.publish.csiro.au/wrhj2024Production Animal StudiesSDG-03:Good heatlh and well-beingSDG-15:Life on lan

The clinical pathology of heartwater. I. Haematology and blood chemistry

Clinical pathological studies were undertaken in 5 calves with experimentally-induced heartwater. The most important findings include a progressive anaemia which may be associated with bone marrow depression and fluctuations in the total and differential white cell count, of which an eosinopenia and a lymphocytosis were the most marked. A severe drop in serum protein, especially in the albumin levels, was observed in all 5 cases . This disease is probably associated with an increased capillary permeability, as the protein content of the pericardial fluid in 1 case that died, approximated that of the serum. The osmolality of the effused fluid was also higher than that of the blood. No significant changes in the serum electrolyte levels occurred, except for total calcium levels which tended to decrease to below normal during the acute stage of the disease. Marked increases in total bilirubin were recorded. This, however, was not associated with liver pathology or haemolysis and may possibly be ascribed to a fasting hyperbilirubinaemia. Darkening of plasma colour was associated with peak rises in total biluribin. Increases in both blood urea and creatinine levels indicate interference with renal glomerular filtration during the acute stage of the disease.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.lmchunu2014mn201

Use of gonadotropin releasing hormone (GnRH) vaccines for behavioural and reproductive control in managed Asian elephant Elephas maximus and African elephant Loxodonta africana populations

Because of their size and reproductive anatomy, surgical castration is not a practical option in adult elephants. However, similar to other species in human care, the effects of gonadectomy are desired in specific situations. This may be for contraceptive purposes, or for behavioural or veterinary management of elephants in human care or wild elephants managed in small reserves. Research into non‐surgical contraceptive measures for wild and domestic animals has resulted in an array of hormonal and immunological options to downregulate gonadal function. Driven by the production‐animal industry, commercial gonadotrophin releasing hormone (GnRH) vaccines are readily and cheaply available. This immunocontraceptive is effective in both males and females as it inhibits gonadotrophic hormone release and, thus, downstream stimulation of testicles and ovaries. Here, available studies from the past 10 years on the GnRH vaccine application in male and female elephants are reviewed. Furthermore, we add our own experience gathered from the treatment of male African elephants Loxodonta africana and female Asian elephants Elephas maximus in human care. The GnRH vaccine offers a viable approach for various management purposes. It should be noted that the GnRH vaccine was not primarily designed as a reversible contraceptive. Therefore, its use must be well justified on an individual basis and the effects closely monitored.https://zslpublications.onlinelibrary.wiley.com/journal/174810902020-07-01hj2020Anatomy and PhysiologyProduction Animal Studie

Regulation of a small, discrete African elephant population through immunocontraception in the Makalali Conservancy, Limpopo, South Africa

Populations of the African elephant, Loxodonta africana, are growing rapidly in southern Africa, to the extent that population control has become essential. The management option of translocation is no longer realistically available, whilst culling has become ethically unacceptable, especially to the general public. Previous immunocontraception trials on elephants with Porcine Zona Pellucida (PZP) vaccine demonstrated that it is safe, effective, reversible, remotely deliverable, and has had no evident adverse side effects. We demonstrate effective contraceptive management of a discrete, small population of free-roaming elephants in the Makalali Conservancy, Limpopo province, South Africa. Complete reproductive control has been demonstrated in all 18 original targeted females, who have by now passed the population's average intercalving interval of 56 months without giving birth. A zero population growth rate has been maintained within this target group since August 2002. On the basis of this small sample over a short period, immunocontraception should be considered a viable means of population management as an alternative to long-term culling strategies in small populations.The Humane Society of the United States (HSUS), the National Research Foundation and Amarula.http://www.sajs.co.zahj2024Centre for Veterinary Wildlife StudiesSDG-03:Good heatlh and well-beingSDG-15:Life on lan

Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana) treated with a gonadotropin-releasing hormone (GnRH) vaccine for inducing anoestrus

BACKGROUND: In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH) vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. METHODS: Between May 2009 - June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM) on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (ImprovacW, Pfizer Animal Health, Sandton, South Africa) 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP) vaccine for four years (2004-2007). RESULTS: All 12 monitored females (8 treated and 4 controls) showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces) were significantly higher (P<0.002) than the dry season (mean 2.59 micrograms/gram dry faeces). CONCLUSIONS: The GnRH vaccination protocol failed to induce anoestrus in the treated female elephants. These results indicate that irregular oestrous cycles occur amongst free-ranging elephants and are not restricted to elephants in captivity. The relationship between ecological conditions and endocrine activity were confirmed. Free-ranging female elephants were observed to not cycle continuously throughout the year in the absence of adult bulls.http://www.rbej.com/content/10/1/63ab2012ab2013 (Author correction)ab2013 (Author correction