Monitoring the endangered population of the antelope Kobus leche smithemani (Artiodactyla: Bovidae), in the Bangweulu ecosystem, Zambia

Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15 000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15 000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.

El lechwe negro (Kobus leche smithemani) es un antílope semi-acuático de tamaño medio que en la actualidad se encuentra en la lista roja de la UICN de especies en peligro de extinción y sólo es endémica de la cuenca del Bangweulu de Zambia. Su población ha disminuido considerablemente, de más de 250 000 a 15 000, debido a las inundaciones que se dieron durante el período 1930-1940, lo que llevó al gobierno de Zambia a declarar todos los hábitats del lechwe negro en áreas protegidas estatales, y a establecer estrategias de administración urgentes necesarias para salvar el resto de la población de la extinción. Utilizando los datos retrospectivos, nuestros resultados muestran que la población ha aumentado de 15 000 animales en 1954 a 55 632 en 2009. La población actual se estima en 34.77% (55 632/160 000) de la capacidad de carga de la cuenca del Bangweulu. Aunque el lechwe Negro es una de las 42 especies que se ofrecen para su utilización consuntiva por la Autoridad de Vida Silvestre de Zambia (ZAWA), sólo el 0.12% y 0.08% de la población actual se ha ofrecido para el safari y la caza residente anual para el período 2005-2009, respectivamente. La utilización de la cuota anual se estima en 67% (n=67) y 81% (n=37) para safari de caza y residente, respectivamente. Por lo tanto, los ingresos totales obtenidos de la utilización del lechwe negro son muy bajos contando sólo el 2.1% de los ingresos totales obtenidos de la utilización de la fauna silvestre. Aunque la tendencia actual de la población está mostrando un incremento unitario de 639 animales por año, está todavía muy por debajo de los niveles ideales para la utilización lucrativa. En este estudio, se demuestra que los cambios ecológicos perjudiciales sobre especies de fauna silvestre, puede conducir a su vulnerabilidad y peligro de extinción, y que la recuperación de su capacidad de carga completa puede exigir una cantidad considerable de tiempo.

Detection of parasites and parasitic infections of free-ranging wildlife on a game ranch in zambia: a challenge for disease control.

Ex-situ conservancies are expanding alternatives to livestock production in Zambia albeit the lack of information on circulating infectious parasites from wildlife. Therefore, 12 wildlife species were examined on a game ranch were all species were found to be infected by Rhipecephalus spp. Haemoparasite infections were estimated at 7.37% (n = 95) with Babesia spp. detected in bushbuck (Tragelaphus scriptus); Anaplasma marginale in impala (Aepyceros melampus) and puku (Kobus vardonii) for the first time in Zambia. The majority of worm species isolated from bovids were not detected in equids and, vice versa. Our findings intimate ecological and behavioural patterns of some animals as deterministic to exposure. Kafue lechwe (Kobus leche kafuensis) had the widest range of worm species with more infected organs than other animals suggesting their semi aquatic nature contributory to prolonged worm exposure compared to other animals. On the other hand, Kafue lechwe had the least tick infections attributable more to shorter attachment periods as they spend prolonged periods submerged in water. Our findings indicate the vital role that wildlife plays in the epidemiology of parasitic diseases. To reduce the infection burden, control measures should be focused on reducing transmission to highly susceptible animal species as described herein.

Monitoring the endangered population of the antelope Kobus leche smithemani (Artiodactyla: Bovidae), in the Bangweulu Ecosystem, Zambia.

Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.

Thelazia rhodesii in the African buffalo, Syncerus caffer, in Zambia.

We report 2 cases of Thelazia rhodesii infection in the African buffaloes, Syncerus caffer, in Zambia. African buffalo calves were captured from the livestock and wildlife interface area of the Kafue basin in the dry season of August 2005 for the purpose to translocate to game ranches. At capture, calves (n=48) were examined for the presence of eye infections by gently manipulating the orbital membranes to check for eye-worms in the conjunctival sacs and corneal surfaces. Two (4.3%) were infected and the mean infection burden per infected eye was 5.3 worms (n=3). The mean length of the worms was 16.4 mm (95% CI; 14.7-18.2 mm) and the diameter 0.41 mm (95% CI; 0.38-0.45 mm). The surface cuticle was made of transverse striations which gave the worms a characteristic serrated appearance. Although the calves showed signs of kerato-conjunctivitis, the major pathological change observed was corneal opacity. The calves were kept in quarantine and were examined thrice at 30 days interval. At each interval, they were treated with 200 µg/kg ivermectin, and then translocated to game ranches. Given that the disease has been reported in cattle and Kafue lechwe (Kobus lechwe kafuensis) in the area, there is a need for a comprehensive study which aims at determining the disease dynamics and transmission patterns of thelaziasis between wildlife and livestock in the Kafue basin.

Detection of Babesia spp. in free-ranging Pukus, Kobus vardonii, on a game ranch in Zambia.

Babesia spp. were detected from 4 asymptomatic pukus captured on a game ranch in central Zambia in October 2008. Blood smears were examined in 4 species of aymptomatic free-ranging antelopes, namely the puku (Kobus vordanii), reedbuck (Redunca arundinum), bushbuck (Tragelaphus sylvaticus), and kudu (Tragelaphus strepsiceros), and showed the presence of Babesia parasites only in the puku. In the puku, the prevalence of babesiosis was estimated at 33.3% (n = 12), while the overall prevalence in all examined animals was 8.5% (n = 47). The parasites showed morphological characteristics of paired ring-like stages with the length varying between 1.61 µm and 3.02 µm (mean = 2.12 µm, n = 27; SD = 0.76 µm). Both the infected and non-infected pukus showed good body condition scores (BCS), while the dominant tick species detected from all animals were Rhipicephalus appendiculatus, Rhipicephalus spp., and Boophilus spp. To our knowledge this is the first report of Babesia spp. infection in pukus in Zambia. These findings suggest that wildlife could play an important role in the epidemiology of babesiosis in Zambia.

Investigating effects of parasite infection on body condition of the Kafue lechwe (Kobus leche kafuensis) in the Kafue basin.

BACKGROUND: The Kafue lechwe (Kobus leche Kafuensis), a medium-sized semi-aquatic antelope, is endemic to the Kafue basin of Zambia. The population of the Kafue lechwe has significantly dropped in the last decades leading to its subsequent inclusion on the red list of endangered species. In order to save the remaining population from extinction, it has become increasingly important that the impact of parasite infection and infestation on the Kafue lechwe is investigated. FINDINGS: Endoparasites accounted for the majority of parasites observed from a study of 40 Kafue lechwe occurring in the the Kafue basin. Amphistoma spp. were present in all animals examined, while Fasciola gigantica had a prevalence rate of 0.525 (95% CI: 0.36 to 0.69) and species of Schistosoma 0.3 (95% CI: 0.15 to 0.45). Among the ectoparasites, Strobiloestrous vanzyli, had a prevalence rate of 0.15 (95% CI: 0.03 to 0.27), while Rhipicephalus appendiculatus had a prevalence of 0.075 (3/40). Our findings indicate that body condition was not influenced by the parasitic infestation in Kafue lechwe. There was no association between sex and parasitic burden (odds ratio = 0.3, 95% CI: 0.8-1.3). However, an association between age and parasitic burden was observed as older animals above 15 years were more likely to get parasite infections than those aged between 1-5 years (odds ratio = 1.5, 95% CI: 1.1-2.4). CONCLUSION: Overall, there was no evidence that parasitic infections and infestations adversely affected the lechwe population on the Kafue basin. These findings indicate that ecto- and endo-parasite infestation might not play a significant role in reducing the Kafue lechwe population on the Kafue basin.

Serosurvey of Brucella spp. infection in the Kafue lechwe (Kobus leche kafuensis) of the Kafue flats in Zambia.

One of the diseases of veterinary and public health importance affecting the Kafue lechwe (Kobus leche kafuensis) on the Kafue flats is brucellosis, for which only scant information is available. During the 2003 (October), 2004 (December), and 2008 (July-December) hunting seasons in the Kafue flats, we conducted a study to determine the seroprevalence of Brucella spp. in the Kafue lechwe and to evaluate serologic tests for detection of Brucella spp. antibodies in lechwe. The Rose Bengal Test (RBT), competitive enzyme-linked immunosorbent assay (cELISA), and fluorescence polarization assay (FPA) were used. A total of 121 Kafue lechwe were hunted for disease investigations in 2003, 2004, and 2008 in the Kafue Flat Game Management Area. Of these, 21.6%, (95% confidence interval [CI]: 14.2-29.1%) had detectable antibodies to Brucella spp. The Kafue lechwe in Lochnivar National Park had higher antibody results than those in Blue Lagoon National Park (odds ratio=3.0; 95% CI: 0.94-9.4). Infection levels were similar in females (21.6%) and males (21.7%). Results were similar among RBT, FPA, cELISA tests, suggesting that these could effectively be used in diagnosing brucellosis in the Kafue lechwe. Our study demonstrates the presence of Brucella infections in the Kafue lechwe in two national parks located in the Kafue flats and further highlights the suitability of serologic assays for testing the Kafue lechwe. Because the Kafue lechwe is the most hunted wildlife species in Zambia, hunters need to be informed of the public health risk of Brucella spp. infection.

Sarcoptes mite epidemiology and treatment in African buffalo (Syncerus caffer) calves captured for translocation from the Kafue game management area to game ranches.

BACKGROUND: In Zambia, translocation of wildlife from National Parks to private owned game ranches demands that only animals free of infectious diseases that could adversely affect the expansion of the wildlife industry should be translocated to game ranches. Sarcoptes mange (Sarcoptes scarbiei) has been involved in the reduction of wildlife populations in some species. RESULTS: Sarcoptes mange (Sarcoptes scarbiei) was detected and eradicated from two herds of African buffalo (Syncerus caffer) calves captured in the Kafue GMA in July 2004 and August 2005. The overall prevalence was estimated at 89.5% (77/86). Sex had no influence on the occurrence and severity of the disease. Of the 86 calves used in the study, 72.1% had good body condition scores, 20.9% were fair and 7.0% were poor. Of the 77 infected calves, 53.2% were mildly infected, 28.6% were moderately and 18.2% were severely infected. Body condition score was correlated to the severity of the infection (r = 0.72, p < 0.000, n = 86) at capture. Eradication of Sarcoptes mites from the entire herd using ivermetcin was dependant on the severity of the infection. The overall ability of ivermectin to clear the infection after the first treatment was estimated at 81.8% (n = 77). It increased to 94.8% and 100% after the second and third treatments respectively. CONCLUSION: This is the first report on the epidemiology and treatment of Sarcoptes mange in African buffaloes in Zambia. This study improves our understanding about Sarcoptes scabiei epidemiology and treatment which will have further applications for the safe animal translocation.

Disease constraints for utilization of the African buffalo (Syncerus caffer) on game ranches in Zambia.

Eco-tourism depending on wildlife is becoming increasingly profitable and landowners are beginning to favor game farming and ecotourism. In these areas, large-scale translocation of wildlife involves a diversity of species and large populations. The African buffalo (Syncerus caffer) is one of the major tourist attractions in Zambia. It accounts for 8.7% and 12.4% of the total animal species hunted in the Game Management Areas and the total hunting revenue earned in Zambia, respectively. It is ecologically an important animal species essential for the purpose of habitat control and facilitating the provision of suitable grazing pastures. However, the rearing of the African buffalo on game ranches has been hampered by its carrier state of the Southern Africa Terroritory (SAT) serotypes of foot and mouth disease virus (FMD). The African buffalo is also known to be a carrier of Theileria parva lawrencei, the causative agent of corridor disease (CD) that continues to have devastating effects on the livestock industry in Zambia. In addition, the importation of buffaloes from countries with populations endemic to bovine tuberculosis is highly restricted. Veterinary regulations in Zambia, strongly advocate against the translocation of buffaloes from protected areas to private ranches for disease control purposes thereby mounting a considerable constraint on the economic and ecological viability of the industry. It is hoped that this review will motivate the relevant government authorities in exploiting ways in which this animal species play a central role in eco-tourism.

Ecology and epidemiology of anthrax in cattle and humans in Zambia.

Anthrax is endemic in Western and North-western Provinces of Zambia. The disease occurs throughout the year and impacts negatively on the economy of the livestock industry and public health in Zambia. During 1989-1995, there were 1626 suspected cases of anthrax in cattle in Western province and of these 51 were confirmed. There were 220 cases of human anthrax cases in 1990 alone and 248 cases during 1991-1998 with 19.1% and 7.7% case fatality rates, respectively. Interplay of the ecology of affected areas and anthropogenic factors seem to trigger anthrax epidemics. Anthrax has drawn considerable attention in recent years due to its potential use as a biological weapon. In this paper, the history, current status and approaches towards the control of the disease in Zambia are discussed. Quarantine measures restrict trade of livestock and exchange of animals for draught power resulting in poor food security at household levels. Challenges of anthrax control are complex and comprise of socio-political, economical, environmental and cultural factors. Inadequate funding, lack of innovative disease control strategies and lack of cooperation from stakeholders are the major constraints to the control of the disease. It is hoped that the information provided here will stimulate continued awareness for the veterinary and medical authorities to maintain their surveillance and capabilities against the disease. This may lead to a culminating positive impact on livestock and human health in the southern African region.