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Fission–fusion dynamics allow animals to manage costs and benefits of group living by adjusting group size. The degree of intraspecific variation in fission–fusion dynamics across the geographical range is poorly known. During 2008–2016, 38 adult female Cape buffalo were equipped with GPS collars in three populations located in different protected areas (Gonarezhou National Park and Hwange National Park, Zimbabwe; Kruger National Park, South Africa) to investigate the patterns and environmental drivers of fission–fusion dynamics among populations. We estimated home range overlap and fission and fusion events between Cape buffalo dyads. We investigated the temporal dynamics of both events at daily and seasonal scales and examined the influence of habitat and distance to water on event location. Fission–fusion dynamics were generally consistent across populations: Fission and fusion periods lasted on average between less than one day and three days. However, we found seasonal differences in the underlying patterns of fission and fusion, which point out the likely influence of resource availability and distribution in time on group dynamics: During the wet season, Cape buffalo split and associated more frequently and were in the same or in a different subgroup for shorter periods. Cape buffalo subgroups were more likely to merge than to split in open areas located near water, but overall vegetation and distance to water were very poor predictors of where fission and fusion events occurred. This study is one of the first to quantify fission–fusion dynamics in a single species across several populations with a common methodology, thus robustly questioning the behavioral flexibility of fission–fusion dynamics among environments., The frequency at which Cape buffalos split and join allows them to adjust to environmental conditions. In 3 distinct populations, the associations between individuals last on average between 1 and 3 days, but seasonal differences exist: In the dry season, buffalos split and join less frequently but stay in the same subgroup for longer periods than in wet season. Vegetation openness and distance to water are poor predictors of where fission and fusion events occur.

At a human/livestock/wildlife interface, Escherichia coli populations were used to assess the risk of bacterial and antibiotic resistance dissemination between hosts. We used phenotypic and genotypic characterization techniques to describe the structure and the level of antibiotic resistance of E. coli commensal populations and the resistant Enterobacteriaceae carriage of sympatric African buffalo ( Syncerus caffer caffer ) and cattle populations characterized by their contact patterns in the southern part of Hwange ecosystem in Zimbabwe. Our results (i) confirmed our assumption that buffalo and cattle share similar phylogroup profiles, dominated by B1 (44.5%) and E (29.0%) phylogroups, with some variability in A phylogroup presence (from 1.9 to 12%); (ii) identified a significant gradient of antibiotic resistance from isolated buffalo to buffalo in contact with cattle and cattle populations expressed as the Murray score among Enterobacteriaceae (0.146, 0.258, and 0.340, respectively) and as the presence of tetracycline-, trimethoprim-, and amoxicillin-resistant subdominant E. coli strains (0, 5.7, and 38%, respectively); (iii) evidenced the dissemination of tetracycline, trimethoprim, and amoxicillin resistance genes ( tet , dfrA , and bla TEM-1 ) in 26 isolated subdominant E. coli strains between nearby buffalo and cattle populations, that led us (iv) to hypothesize the role of the human/animal interface in the dissemination of genetic material from human to cattle and toward wildlife. The study of antibiotic resistance dissemination in multihost systems and at anthropized/natural interface is necessary to better understand and mitigate its multiple threats. These results also contribute to attempts aiming at using E. coli as a tool for the identification of pathogen transmission pathway in multihost systems.

We report on the long-distance movements of subadult female buffalo within a Transfrontier Conservation Area in Africa. Our observations confirm that bovine tuberculosis and other diseases can spread between buffalo populations across national parks, community land, and countries, thus posing a risk to animal and human health in surrounding wildlife areas.

International audience; Understanding the spatiotemporal dynamics of human-wildlife interfaces is important for the sustainable management of protected areas and wildlife conservation. We investigated the drivers of domestic and wild herbivore habitat selection at the edge of an unfenced protected area adjacent to Hwange National Park, Zimbabwe. We used GPS data to quantify the movement patterns of elephant bulls, buffalo and cattle at multiple scales and according to seasonal changes of surface water availability. Cattle, elephant and buffalo prefer open grassland habitats found close to water but elephant and buffalo avoid cattle differently. During the rainy season, cattle enter the protected area daily; buffalo avoid cattle completely at the home range scale, whereas elephant bulls avoid cattle at finer scales by favoring temporal niche shift. Elephant bulls avoid direct encounters with cattle (or people) during the day but come closer to the boundary and to water at night when cattle are kept in enclosures close to the homesteads. During the dry season, when cattle range further into the protected area in search of forage, buffalo and cattle spatial overlap increases as water dependence takes precedence over avoidance. Elephant bulls range closer to the boundary at night and increase the number of excursions into the Communal Area. Cattle herding creates a buffer zone between wildlife areas and human settlements because wild herbivores strongly avoid livestock and people. However, avoidance only lasts as long as resources are abundant. Our study suggests that long-term planning of both artificial water provisioning and traditional cattle herding practices could help maintaining spatial segregation and thus mitigate conservation conflicts such as pathogen transmission, crop raiding or livestock depredation.

Rift Valley Fever (RVF) is a mosquito-borne zoonosis, which may cause significant losses for the livestock sector and have serious public health implications. Egypt has been repeatedly affected by RVF epidemics, mainly associated to the importation of animals from sub-Saharan countries, where the disease is endemic. The objective of our study was the improvement of the surveillance and control strategies implemented in Egypt. In order to do that, first we evaluated the legal trade of live animals into and within Egypt. Then, we assessed the risk of Rift Valley Fever virus (RVFV) transmission within the country using a multi-criteria evaluation approach. Finally, we combined the animal trade and the risk of RVFV transmission data to identify those areas and periods in which the introduction of RVFV is more likely. Our results indicate that the main risk of RVFV introduction is posed by the continuous flow of large number of camels coming from Sudan. The risk of RVFV transmission by vectors is restricted to the areas surrounding the Nile river, and does not vary significantly throughout the year. Imported camels are taken to quarantines, where the risk of RVFV transmission by vectors is generally low. Then, they are taken to animal markets or slaughterhouses, many located in populated areas, where the risk of RVFV transmission to animals or humans is much higher. The measures currently implemented (quarantines, vaccination or testing) seem to have a limited effect in reducing the risk of RVFV introduction, and therefore other (risk-based) surveillance strategies are proposed., Author summary Rift Valley Fever (RVF) is a mosquito-transmitted disease, which may affect animals (ruminants and camels) and cause severe disease. Egypt has been affected by RVF in the past, and it is considered at risk because of the importation of animals from endemic countries. We developed a map of the risk of RVFV transmission by vectors using current knowledge on the disease, and then combined it with animal trade data to identify the areas at the highest risk for RVFV introduction. Our results indicate that the main risk is posed by camels imported from Sudan, when they are transported to animal markets or slaughterhouses, which are generally located in areas where the risk of RVFV transmission is much higher. In fact many of them are located in the proximities or within the main cities, resulting in an increased risk of RVFV transmission to humans.

A study was conducted to investigate seroprevalence and risk factors for Brucella species infection in cattle and some wildlife species in communities living at the periphery of the Great Limpopo Transfrontier Conservation Area in south eastern Zimbabwe. Three study sites were selected based on the type of livestock–wildlife interface: porous livestock–wildlife interface (unrestricted); non-porous livestock–wildlife interface (restricted by fencing); and livestock–wildlife non-interface (totally absent or control). Sera were collected from cattle aged ≥ 2 years representing both female and intact male animals. Sera were also collected from selected wild ungulates from Mabalauta (porous interface) and Chipinda (non-interface) areas of the Gonarezhou National Park. Samples were screened for Brucellaantibodies using the Rose Bengal plate test and confirmed by the complement fixation test. Data were analysed by descriptive statistics and multivariate logistic regression modelling. In cattle, brucellosis seroprevalence from all areas was 16.7% (169/1011; 95% CI: 14.5–19.2%). The porous interface recorded a significantly (p = 0.03) higher seroprevalence (19.5%; 95% CI: 16.1–23.4%) compared to the non-interface area (13.0%; 95% CI: 9.2–19.9%).The odds of Brucellaseropositivity increased progressively with parity of animals and were also three times higher (OR = 3.0, 2.0 < OR < 4.6, p < 0.0001) in cows with history of abortion compared to those without.Brucella antibodies were detected in buffaloes; 20.7% (95% CI: 13.9–29.7%) form both study sites, but no antibodies were detected from impalas and kudus. These results highlight the importance of porous interface in the interspecies transmission of Brucella species and that independent infections may be maintained in buffalo populations. Thus, brucellosis control aimed at limiting animal inter-species mixing may help reduce the risk of human brucellosis in interface areas. Further studies should aim at establishing subspecies identity and direction of possible transmission of brucellosis between wildlife and livestock.

Little is known about the levels of stress experienced by African buffalos affected by injury, disease, or socio-ecological and anthropogenic factors. To be able to start filling this gap, we examined the suitability of two 11-oxoaetiocholanolone enzyme-immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (FGMs) with a 5-3-ol-11-one structure (3 ,11oxo-CM), respectively, for monitoring stress-related physiological responses in African buffalo. An adrenocorticotrophic hormone (ACTH) challenge in one male and one female housed at Mokopane Biodiversity Conservation Centre, South Africa, showed a threefold increase in circulating cortisol levels in a sample taken 40 min post-injection. Corresponding 11,17-DOA levels increased tenfold (female) and 15-fold (male) above baseline, and 3,11oxo-CM concentrations increased ninefold (female) and 12-fold (male) above pre-injection levels, indicating that both EIAs are suitable for measuring FGMs in African buffalo.In addition, 11,17-DOA levels monitored during the adaptation process of individual housing revealed an up to 14-fold elevation in FGMs. Storage of faeces at ambient temperature for up to 16 h post-defecation resulted in an significant increase in 11,17-DOA levels 2 h after defecation. Finally, higher individual baseline 11,17-DOA concentrations were found in samples defecated overnight, indicating a possible diurnal effect in excretion of FGMs in African buffalo.Key words: faecal glucocorticoid metabolites, ACTH challenge test, animal separation, hormone degradation rate, circadian variation

This study aims to characterize buffalo veal supply chain in 5 villages around Cairo. Value chain approach was applied to analyze veal supply chain using the data of 82 farmers, 4 traders and 4 butchers. Economic analysis was applied to different scenarios of raising calves using buffalo milk, cow milk or milk replacer. Survey analysis showed that 65% of farmers sold veal as early as possible. However, 61% of farmers sold their calves for economic reasons, 14 % for technical reasons and 25 % for both economic and technical reasons. Survey analysis showed the high demand on veal meat due to its unique quality. Technical and economic pressures on farmers motivate them to sell veal. Buffalo veal chain provides farmers with money to cover their needs, offers jobs through the whole year. Many butchers and traders prefer to slaughter veal due to the low price of veal compared with older or heavier cattle. Economic analysis of different alternatives to raise calves proved the feasibility of using milk replacer compared with cow or buffalo milk. Slaughtering veal, lack of finance and training programs to raise buffalo calves decreased the contribution of buffaloes in Egyptian meat market. High demand of veal meat and veal selling decision sustain the veal supply chain around Cairo. This study confirms that all chain actors and the related enterprises should be considered to set new regulations for the current veal chain.

SUMMARYIn southern African transfrontier conservation areas (TFCAs), people, livestock and wildlife share space and resources in semi-arid landscapes. One consequence of the coexistence of wild and domestic herbivores is the risk of pathogen transmission. This risk threatens local livelihoods relying on animal production, public health in the case of zoonoses, national economies in the context of transboundary animal diseases, and the success of integrated conservation and development initiatives. The level of interaction between sympatric wild and domestic hosts, defining different wildlife/livestock interfaces, characterizes opportunities of pathogen transmission between host populations. Exploring the relationship between infection burden and different types of wildlife/domestic interfaces is therefore necessary to manage the sanitary risk in animal populations through control options adapted to these multi-host systems. Here, we assessed the infection burdens of sympatric domestic cattle (Bos taurus/Bos indicus) and African buffalo (Syncerus caffer) at an unfenced interface and compared the infection burdens of cattle populations at different wildlife/livestock interfaces in the Great Limpopo TFCA. Patterns of infection in ungulate populations varied between wild and domestic hosts and between cattle populations at different wildlife/livestock interfaces. Foot-and-mouth disease, Rift Valley fever and theileriosis infections were detected in buffalo and cattle at unfenced interfaces; bovine tuberculosis was only present in buffalo; and brucellosis and lumpy skin disease only in cattle. At unfenced interfaces, cattle populations presented significantly higher Theileria parva and brucellosis prevalence. We hypothesize that cattle populations at wildlife/livestock interfaces face an increased risk of infection compared to those isolated from wildlife, and that the type of interface could influence the diversity and quantity of pathogens shared. Additional host behavioural and molecular epidemiological studies need to be conducted to support this hypothesis. If it is confirmed, the management of wildlife/livestock interfaces will need to be considered through the prism of livestock and public health.

This study investigates the presence of Enterocytozoon bieneusi in domestic and wild animals living in the wildlife/livestock interface area of the Kruger National Park (KNP) in South Africa. Fifty fecal samples from domestic calves in rural communities and 142 fecal samples from impala (Aepyceros melampus) and buffalo (Syncerus caffer) in the KNP were analysed for Enterocytozoon bieneusi, using a nested PCR targeting the internal transcribed spacer of the rRNA gene. All wildlife samples were negative for E. bieneusi, whereas nine (18%) calf samples were positive. Three cattle specific genotypes (group 2) were identified, belonging to the known genotypes BEB4 and I, and one novel genotype (BEB3-like). One human-pathogenic genotype (D) was detected in one calf. This is the first study on microsporidia performed in a wildlife/livestock interface area of sub-Saharan Africa. Our findings show that at least one genotype of zoonotic importance is circulating in native cattle in the study area and the rest of the identified microsporidia were host-specific genotypes. Larger studies in domestic animals, humans and wildlife are necessary to assess the public health significance of E. bieneusi in that interface area.

Over a decade ago, foot-and-mouth disease (FMD) re-emerged in Southern Africa specifically in beef exporting countries that had successfully maintained disease-free areas in the past. FMD virus (FMDV) serotype SAT2 has been responsible for a majority of these outbreaks. Epidemiological studies have revealed the importance of the African buffalo as the major wildlife FMD reservoir in the region. We used phylogeographic analysis to study dynamics of FMD transmission between buffalo and domestic cattle at the interface of the major wildlife protected areas in the region currently encompassing two largest Transfrontier conservation areas: Kavango–Zambezi (KAZA) and Great Limpopo (GL). Results of this study showed restricted local occurrence of each FMDV SAT2 topotypes I, II, and III, with occasional virus migration from KAZA to GL. Origins of outbreaks in livestock are frequently attributed to wild buffalo, but our results suggest that transmission from cattle to buffalo also occurs. We used coalescent Bayesian skyline analysis to study the genetic variation of the virus in cattle and buffalo, and discussed the association of these genetic changes in the virus and relevant epidemiological events that occurred in this area. Our results show that the genetic diversity of FMDV SAT2 has decreased in buffalo and cattle population during the last decade. This study contributes to understand the major dynamics of transmission and genetic variation of FMDV SAT2 in Southern Africa, which will could ultimately help in designing efficient strategies for the control of FMD at a local and regional level.

This thesis includes four parts to characterize Buffalo milk and veal chains at different chain levels, the objectives of the first part were to identify the diversity of different chains and more deeply to determine main actors along the milk value chains in three villages to understand how these chains work. Also, milk analysis was applied to study the effect of location on milk composition, milk urea nitrogen (MUN) and somatic cell count (SCC). Field visits and interview are used to collect data. Milk samples were collected from farmers through 2013/14. Results indicated that there were a short chain and a long chain. Short chain achieved higher profit for farmers and reasonable price for consumers compared to long chain. While long chain provide s a lot of jobs. MUN, SCC and milk composition could be used as diagnostic tools for different regions to identify the most priority services and extension needs at village level. The aim of the 2nd part was to suggest a methodology to characterize the diversity of dairy farming systems in Egypt to understand the traditional dairy sector. Data were collected from 65 farmers in three villages through three consecutive seasons. Based on multiple factorial and cluster analyses, six farmer s' group were identified. Milk production was a major activity in very small land farms, the sustainability of this sector facing the lack of technical support and lack of pricing system for milk and feedstuffs, more governmental and NGOs projects needed to supply farmers with high quality forage seeds, high producing animals and veterinary services. So, considering the diversity of farming systems, one agricultural policy will not fit all farmers' categories taking into account the region and the season. The objective of the 3rd part was to apply a SWOT analysis on a traditional milk chain, particularly buffalo skimmed milk chain around greater Cairo, which considered as one of the main dairy markets in Egypt. Main stakeholders of the chain were farmers, milk collection points, milk collection center, and dairy processing units. SWOT analysis allowed highlighting the major role of social network to explain the flexibility and adaptation of this sector to the major constraints in linked with international competitiveness and national constraints, mainly on land access. These elements could help decision makers and developers to prioritize sustainable development activities in link with agriculture global agenda. The aim of fourth part was to characterize the veal supply chain using survey analysis for different actors along the chain and to understand the preference of some meat consumers to veal meat through comparing meat quality parameters of buffalo meat categories in Egyptian market including meat quality analysis of veal, fattening males and culled females. Survey analysis results indicated that 65 % of Egyptian farmers sold veal as early as possible. About 61 % of these farmers sold their animals for economic reasons, 14 % for technical reasons and 25 % for both reasons. Fat content and cholesterol levels were lower in veal meat compared with fattening calves or culled females; the same trend was observed for shear force value s and cooking loss percentage. These results explained why the veal meat is regularly consumed by elders, sick peoples and employees with limited physic al activities, veal showed high tenderness and more attractive color, in contrast veal contained lower fat and cholesterol levels.

We test the extent to which fence damage or fence permeability (resulting from human and elephant damage) influences patterns of cattle and buffalo movement at the periphery of Gonarezhou National Park, Zimbabwe. We used spoor data to detect and compare the frequency of cattle and buffalo movement across the fence boundary. Results show that spoor proportions for cattle were significantly higher on fence partially damaged by humans than buffalo spoor. Conversely, buffalo spoor proportions were significantly higher on sections with totally removed fence as a result of elephant damage. Results suggest that cattle and buffalo use different sections of the damaged fence. (Resume d'auteur)

The aim of this study was to suggest a methodology to characterize the diversity of dairy farming systems in Nile valley lands (NVLs) and newly reclaimed lands (NRLs) in Egypt to understand the traditional dairy sector. Data were collected from 65 farmers in three villages through three consecutive seasons. Interviews and field visits were done at farm level. Based on multiple factorial and cluster analyses, six farmer groups were identified according to land and livestock assets, milk production and selling. Milk marketing was influenced by season, farmers' traditions, and market access. Structure highlights the dominance of small scale crop-livestock system, farm family depends on milk as a source of protein and fat for family food and as a main source of income especially in old lands, while in NRLs, there was a higher crop-livestock integration and complementarity to cover family and farm expenses, so paid services strategy could fit dairy sector in new land. Milk production constitutes a major activity in very small land farms, the sustainability of this sector facing the lack of technical support and lack of pricing system for milk and feedstuffs, where more governmental and non-governmental projects needed to supply farmers with high quality forage seeds, high producing animals and veterinary services. So, considering the diversity of farming systems, one agricultural policy will not fit all farmers' categories. Also, governmental and non-governmental services should be reasoned according to the region and the season.

Aim Home range (HR) metrics are widely used in ecology and conservation, but the quantitative basis for choosing and parameterizing metrics is weak. Home range estimates are ecological and statistical hypotheses that must balance type I and type II errors. Here, we present and test a new approach to fine-tuning and comparing HR estimates using the area under the curve (AUC) statistic. Location Test data are taken from telemetry studies of 44 individual ducks in southern Africa and nine buffaloes in southern and western Africa. Methods We use a meta-analysis of AUC statistics to compare the performance of four standard HR metrics on data from 44 ducks (two species) and nine African buffaloes. Results The AUC method emerges as a useful and accessible statistical tool. It captures clear differences between HR estimators as well as providing a way of fine-tuning parameters for an individual HR estimate. Code to run the HR AUC analyses in R is provided. As argued by others, we found that kernel density estimators offer the best combination of ecological and statistical validity, while estimators that use minimum convex polygons at any stage of the algorithm perform poorly and should be avoided. Main conclusions The AUC statistic provides a readily implementable and straightforward approach to comparing different HR metrics and to selecting parameters for individual metrics. It thus offers a valuable tool for conservation efforts that seek to define HRs for species or populations. The use of the AUC in this new context further contributes to solidifying the interface between species occurrence models and HR estimators. (Resume d'auteur)

Water and forage are key non-substitutable resources for herbivores in arid and semi-arid ecosystems. The distribution of surface water determines the distribution and abundance of water dependent animal species yet little is known about the processes involved at the individual level. Thirteen African savanna elephant family groups and ten bulls (Loxodonta Africana) were tracked with GPS collars within and on the outskirts of Hwange National Park, Zimbabwe. Elephants behave as multiple central place foragers: They visit waterholes periodically every 5h, 24h, 48h or 72h and travel further from water during longer trips. During the dry season, temperatures increase and forage becomes depleted closer to water. Elephant family groups visit waterholes more often by increasing the proportion of briefer trips and abandoning 72h trips. However, they forage further during 24h trips by increasing travelling speed. Elephant movement patterns revealed locomotional and navigational abilities are at the core of their coping strategies although they are seldom allowed to vary in most foraging models of animal's use of heterogeneously distributed resources. During these foraging trips, family herds select for areas with low waterhole density at multiple scales. Selection strength for low density areas increases with both distance to water and the advancement of the dry season. Although scaling effects are widely recognized, the effects of the spatial distribution of multiple central places constraining foraging have been ignored yet they determine depletion effects and their feedbacks on habitat selection. I also showed that wildlife strongly avoid livestock and people that herd them at the boundary of a protected area during the rainy season yet avoidance decreases during the dry season when foraging and drinking resources become scares. Elephants are increasingly constrained by surface water availability during the dry season as their drinking requirements increase while they strive to main their forage intake. This study provides quantitative assessment of individual water dependence and of landscape effects of surface water distribution on a large herbivore. These findings can inform surface water management in contexts of aridification resulting from climate change., L’eau et le fourrage sont deux ressources non substituables pour les herbivores dans les écosystèmes arides et semi-arides. La distribution spatiale de l’eau de surface détermine la distribution et l’abondance des espèces dépendantes de l’eau. Cependant les processus impliqués à l’échelle individuelle demeurent méconnus. Treize groupes familiaux d’éléphants d’Afrique (Loxodonta africana) et dix mâles ont été équipé de colliers GPS dans le parc National de Hwange, au Zimbabwe, et à sa périphérie. Les éléphants fourragent autour de multiples points centraux : ils visitent un point d’eau périodiquement toutes les 5h, 24h, 48h ou 72h et s’éloignent plus de l’eau lorsque ils font des trajets de plus longue durée. Pendant la saison sèche, la température augmente et les ressources fourragères s’épuisent à proximité de l’eau. Les groupes familiaux d’éléphants visitent les points d’eau plus souvent en augmentant la fréquence des trajets courts et en abandonnant les trajets de 72h. Cependant, ils parviennent à se rendre plus loin de l’eau pendant les trajets de 24h en augmentant la vitesse de déplacement. Ainsi les patrons de déplacement révèlent que les capacités de locomotion et de navigation des éléphants sont au cœur de leur stratégie d’adaptation à la saison sèche. Malgré cela, ces capacités sont rarement incluses dans les modèles d’approvisionnement dans des environnements hétérogènes. Pendant ces trajets, les groupes familiaux sélectionnent les zones de faible densité de points d’eau à des échelles multiples. La force de la sélection pour ces zones de faible densité augmente avec la longueur du trajet et au cours de la saison. Malgré le fait que l’importance des échelles spatiales soit bien établie dans la littérature, les contraintes associées à l’utilisation de multiples points centraux distribués de manière hétérogène dans le paysage ont été négligé alors que cette distribution détermine le degré d’épuisement des ressources fourragères et les rétroactions sur la sélection de l’habitat. J’ai aussi montré que la faune sauvage évite fortement le bétail et les humains qui les conduisent en périphérie d’une zone protégée pendant la saison des pluies. Cependant cet évitement décline au cours de la saison sèche en raison de l’assèchement des points d’eau et de la raréfaction des ressources fourragères. Les éléphants sont de plus en plus contraints par la distribution de l’eau de surface en saison sèche en raison de l’augmentation de leur besoins en eau tandis qu’ils tentent de maintenir leur approvisionnement en fourrage. Cette étude donne une évaluation quantitative de la contrainte en eau à l’échelle individuelle ainsi que les effets de la distribution en eau dans le paysage sur un grand herbivore. Ces résultats peuvent guider les politiques de gestion de l’eau dans un contexte d’aridification dû au changement climatique.

International audience; The role which West and Central African wildlife populations might play in the transmission dynamics of FMD is not known nor have studies been performed in order to assess the distribution and prevalence of FMD in wild animal species inhabiting those specific regions of Africa. This study reports the FMD serological profile extracted from samples (n = 696) collected from wildlife of West and Central Africa between 1999 and 2003. An overall prevalence of FMDV NSP reactive sera of 31.0% (216/696) was estimated, where a significant difference in seropositivity (p = 0.000) was reported for buffalo (64.8%) as opposed to other wild animal species tested (17.8%). Different levels of exposure to the FMDV resulted for each of the buffalo subspecies sampled (p = 0.031): 68.4%, 50.0% and 0% for Nile Buffalo, West African Buffalo and African Forest Buffalo, respectively. The characterisation of the FMDV serotypes tested for buffalo found presence of antibodies against all the six FMDV serotypes tested, although high estimates for type O and SAT 3 were reported for Central Africa. Different patterns of reaction to the six FMDV serotypes tested were recorded, from sera only positive for a single serotype to multiple reactivities. The results confirmed that FMDV circulates in wild ruminants populating both West and Central Africa rangelands and in particular in buffalo, also suggesting that multiple FMDV serotypes might be involved with type O, SAT 2 and SAT 1 being dominant. Differences in serotype and spill-over risk between wildlife and livestock likely reflect regional geography, historical circulation and differing trade and livestock systems.

This study determined the prevalence of Cryptosporidium spp. oocysts in faecal samples from elephant ( Loxodonta africana ), buffalo ( Syncerus caffer ) and impala ( Aepyceros melampus ) in the Kruger National Park (KNP) and an adjacent game reserve in South Africa. Two of the study areas were in close proximity to rural communities on the western KNP boundary and the third study area was located in the centre of the KNP. Fresh stool samples ( n = 445) were collected and tested using an immunofluorescent antibody test (IFA) for Cryptosporidium parvum . A total of 278 of these were randomly selected (approximately 90 samples per wildlife species) and tested with the modified Ziehl Neelsen staining technique (ZN) for Cryptosporidium spp. The prevalence of Cryptosporidium spp. was highest in elephants (25.8% [95% confidence interval: 17.3, 35.9]), compared to buffalo (5.5% [1.8, 12.4]) and impala (4.3% [1.2, 10.5]). C. parvum showed similar patterns, being most prevalent in elephants (4.2% [1.5, 8.8]), compared to buffalo (1.4% [0.2, 5.1]) and impala (1.9% [0.4, 5.3]). 29 samples, including ZN positive and IFA positive samples, were retested using a real time PCR (rtPCR) technique. Of the 28 ZN-positive samples, 14 (50%) were positive with rtPCR and of the 9 IFA-positive samples 6 (67%) were confirmed positive by rtPCR. The prevalence of Cryptosporidium oocysts was significantly higher in both of the two study areas adjacent to the western KNP boundary compared to the area in the centre of the KNP ( OR = 3.2 [1.2, 9.0]; P = 0.024). Our study demonstrates for the first time the presence of Cryptosporidium spp. in wildlife in South Africa. The transmission of this parasite between wildlife, domestic animals and humans is a plausible hypothesis and represents a potential risk for immunodeficient human populations.

Kernel-based utilization distribution (UD) estimates are powerful tools to investigate home range space use and resource selection in many vertebrate species. By ignoring local movement information provided by the serial correlation between successive locations and the constraints to movement imposed by obvious boundaries, the classical kernel method results in loosely estimated UDs that tend to overflow into never-visited areas and eventually in possibly biased estimates of space use and habitat selection. We improved biological relevance of kernel home range space use estimates by incorporating both movement (and activity) information and boundary constraints.

International audience; Trypanosoma evansi is a protozoan blood parasite and etiologic agent of “surra,” a disease affecting a wide range of domestic and wild mammals, some identified as potential reservoirs. Although T. evansi has been detected in several small wild rodent species, their role in the epidemiology of surra is unclear. There is molecular evidence of T. evansi in wild rodents in Asia, but it is not known whether they can carry the parasite for sufficient time to significantly contribute to the epidemiology of surra. We assessed the susceptibility of the Oriental house rat (OHR; Rattus tanezumi) to T. evansi infection. Five adult male OHRs trapped in Bangkhen district, Bangkok, Thailand, and five laboratory Wistar rats (Rattus norvegicus) as positive controls, were experimentally infected with a local strain of T. evansi. The five controls and three of the five OHRs were highly susceptible and rapidly exhibited the high levels of parasitemia usually observed in Wistar rats. They died or were euthanized just prior to expected death. Two OHRs presented fluctuating levels of parasitemia, without obvious clinical signs, throughout 40 d of monitoring. These results highlight the moderate susceptibility of some OHRs and their ability to carry the infection over time. Along with the molecular evidence of T. evansi in captured OHRs (demonstrated elsewhere), our results bring new information on the potential role of OHRs in the complex epidemiology of surra.

In Southern Africa, the African buffalo (Syncerus caffer) is the natural reservoir of foot and mouth disease (FMD). Contacts between this species and cattle are responsible for most of the FMD outbreaks in cattle at the edge of protected areas, which generate huge economic losses. During the late 1980's and 90's, the erection of veterinary cordon fences and the regular vaccination of cattle exposed to buffalo contact at the interface of the Kruger National Park (KNP), proved to be efficient to control and prevent FMD outbreaks in South Africa. However, since 2000, the efficiency of those measures has deteriorated, resulting in an increased rate of FMD outbreaks in cattle outside KNP, currently occurring more than once a year. Based on retrospective ecological and epidemiological data, we developed a stochastic quantitative model to assess the annual risk of FMD virus (FMDV) transmission from buffalo to cattle herds present at the KNP interface. The model suggests that good immunization of approximately 75% of the cattle population combined with a reduction of buffalo/cattle contacts is an efficient combination to reduce FMDV transmission to one infective event every 5.5 years, emulating the epidemiological situation observed at the end of the 20th century, before current failure of control measures. The model also indicates that an increasing number of buffalo present in the KNP and crossing its boundaries, combined with a reduction in the vaccination coverage of cattle herds at the interface, increases 3-fold the risk of transmission (one infective event per year).The model proposed makes biological sense and provides a good representation of current knowledge of FMD ecology and epidemiology in Southern Africa which can be used to discuss with stakeholders on different management options to control FMD at the wildlife livestock interface and updated if new information becomes available. It also suggests that the control of FMD at the KNP interface is becoming increasingly challenging and will probably require alternative approaches to control this disease and its economic impact.

In southern Africa, TransFrontier Conservation Areas (TFCAs) are promoting the sustainable coexistence between Mankind and Nature, and are seeking to find a balance between wildlife conservation, agricultural production and natural resource use. In these TFCAs, the various land use types include wildlife/domestic interfaces prone to create human/wildlife conflicts. Amongst those conflicts, disease transmission between buffalo and cattle (and potentially to human for zoonoses) is a serious concern. In this study, we GPS-tracked buffalo and cattle herds in the Great Limpopo TFCA in order to understand disease transmission and estimate the risk of emerging pathogen spillover. This protocol makes it possible to investigate inter-species contacts along multiple spatiotemporal windows, and thus risks of transmission of various pathogens. Regarding buffalo specifically, Adult females were shown to range within stable home ranges, displaying little overlap with adjacent buffalo herds. However, interindividual association patterns strongly challenged the standard concept of herd. Interestingly, two of the young GPS-tracked females displayed long-range (70- 90kms) movements in a few week times, linking distant buffalo populations across communal lands. This shed light on a poorly described behaviour that has major implications in disease ecology in the GLTFCA. We conclude by discussing the implication of buffalo/cattle interactions for disease transmission, particularly in the context of transboundary disease transmission and by listing some hypotheses that will require testing in the near future to manage the health issue at buffalo/cattle interfaces in Africa.

Rift Valley fever (RVF) is endemic in many countries in Sub-Saharan Africa and is responsible for severe outbreaks in livestock characterized by a sudden onset of abortions and high neonatal mortality. During the last decade, several outbreaks have occurred in Southern Africa, with a very limited number of cases reported in Botswana. To date, published information on the occurrence of RVF in wild and domestic animals from Botswana is very scarce and outdated, despite being critical to national and regional disease control. To address this gap, 863 cattle and 150 buffalo sampled at the interface between livestock areas and the Chobe National Park (CNP) and the Okavango Delta (OD) were screened for the presence of RVF virus neutralizing antibodies. Antibodies were detected in 5.7% (49/863), 95% CI [4.3%-7.5%] of cattle and 12.7% (19/150), 95% CI [7.8%-19.5%] of buffalo samples. The overall prevalence was significantly higher (p=0.0016) for buffalo (12.7%, 95% CI [7.8-19.5]) than for cattle (5.7%, 95% CI [4.3-7.5]). Equally, when comparing RVF seroprevalence in both wildlife areas for all pooled bovid species, it was significantly higher in CNP than in OD (9.5% vs 4%, respectively; p=0.0004). Our data provide the first evidence of wide circulation of RVF virus in both buffalo and cattle populations in Northern Botswana and highlights the need for further epidemiological and ecological investigations on RVF at the wildlife-livestock-human interface in this region.

Along with the elephant and the wildbeest, the African buffalo (Syncerus caffer) is the most dominant species in terms of biomass but also the most widespread herbivore. It exhibits extreme morphological variability at large geographical scale, which has led to controversies about its taxonomic status. Nowadays, the African buffalo experience a severe reduction in population size and geographical distribution, as a result of human demographic expansion, overexploitation, habitat degradation and diseases. Using different kinds of markers on a large sampling set, we aimed to infer the genetic diversity and phylogeographic history of the African buffalo at the pan-African spatial distribution (N=766), as well as to assess the genetic health and the population structure of southern African Cape buffalo populations that face gene flow restriction (N=264). Analyses highlighted the existence of two distinct lineages at the continental scale: West and Central African populations (S.c. nanus, S.c. brachyceros, S.c. aequinoctialis) and East and Southern African populations (S.c. caffer). The two lineages likely expanded and diverged in the late to middle Pleistocene from an ancestral population located around the current-day Central African Republic. They probably adapted their morphology to colonize new habitats, hence developing the variety of ecophenotypes observed today. The finer scale axis- concentrated on southern Africa allowed identifying three genetic clusters. The splitting period suggests that the current pattern results from human-induced factors and/or from the aridification process that occurred during the Holocene. Lower differentiation estimates were observed between localities that experienced translocation over the last century. The two main clusters displayed high intra-cluster genetic diversity, low inter-cluster differentiation, and an absence of inbreeding depression signal, while the third one- a tiny population enclosed within an isolated protected area, experienced genetic drift. All those information are particularly essential within the context of conservation programs currently undertaken to restore genetic diversity of African buffalo populations. (Texte intégral)

La mégapole du Caire compte aujourd’hui près de 20 millions d’habitants. En son cœur et dans sa périphérie subsiste une activité agricole organisée sur une base familiale. Ce chapitre éclaire la situation des exploitations, qui contribuent à l’approvisionnement alimentaire du Caire, en particulier en produits laitiers et maraîchers. Les données sont issues d’une étude conduite dans le cadre du projet Dairy entre le Cirad, l’Universit...

Surra, caused byTrypanosoma evansi, is a neglected disease due to frequent subclinical evolution, especially in bovines in Asia. However, acute and chronic signs are regularly observed, with significant sanitary and economic impacts. In this study, we evaluated and applied an indirect-ELISA test for the detection of anti-T. evansiimmunoglobulin G in buffaloes using antibovine conjugate. Based on buffalo reference sera from the Philippines, a two-graph receiver operating characteristics analysis (TG-ROC) was conducted to define an optimal cut-off value; sensitivity and specificity were estimated at 92.5% and 94.2%, respectively. A cross-sectional serological survey was carried out in the major buffalo breeding areas of Thailand; 892 buffaloes from 8 provinces were sampled in North, Northeastern, and Southern Thailand. Seropositive buffaloes were found in all 8 provinces, on 20.3% of farms for an overall prevalence of 12.2% (95% CI 10.2–14.5%). Nearly one-third of the sampled population was exposed to infection. Broader sampling would be necessary but is not possible in the southern half-wild breeding systems. According to our results, buffaloes may constitute a large and robust reservoir forT. evansi, which is a permanent threat to other livestock such as cattle and horses as well as wild animals such as elephants in Southest Asia.

African wildlife experienced a reduction in population size and geographical distribution over the last millennium, particularly since the 19th century as a result of human demographic expansion, wildlife overexploitation, habitat degradation and cattle-borne diseases. In many areas, ungulate populations are now largely confined within a network of loosely connected protected areas. These metapopulations face gene flow restriction and run the risk of genetic diversity erosion. In this context, we assessed the “genetic health” of free ranging southern African Cape buffalo populations (S.c. caffer) and investigated the origins of their current genetic structure. The analyses were based on 264 samples from 6 southern African countries that were genotyped for 14 autosomal and 3 Y-chromosomal microsatellites. The analyses differentiated three significant genetic clusters, hereafter referred to as Northern (N), Central (C) and Southern (S) clusters. The results suggest that splitting of the N and C clusters occurred around 6000 to 8400 years ago. Both N and C clusters displayed high genetic diversity (mean allelic richness (A r ) of 7.217, average genetic diversity over loci of 0.594, mean private alleles (P a ) of 11), low differentiation, and an absence of an inbreeding depression signal (mean F IS = 0.037). The third (S) cluster, a tiny population enclosed within a small isolated protected area, likely originated from a more recent isolation and experienced genetic drift (F IS = 0.062, mean A r = 6.160, P a = 2). This study also highlighted the impact of translocations between clusters on the genetic structure of several African buffalo populations. Lower differentiation estimates were observed between C and N sampling localities that experienced translocation over the last century. We showed that the current genetic structure of southern African Cape buffalo populations results from both ancient and recent processes. The splitting time of N and C clusters suggests that the current pattern results from human-induced factors and/or from the aridification process that occurred during the Holocene period. The more recent S cluster genetic drift probably results of processes that occurred over the last centuries (habitat fragmentation, diseases). Management practices of African buffalo populations should consider the micro-evolutionary changes highlighted in the present study.

Background: The African buffalo (Syncerus caffer) is a host for many pathogens known to cause economically important diseases and is often considered an important reservoir for livestock diseases. Theileriosis, heartwater, babesiosis and anaplasmosis are considered the most important tick-borne diseases of livestock in sub-Saharan Africa, resulting in extensive economic losses to livestock farmers in endemic areas. Information on the distribution of tick-borne diseases and ticks is scarce in Northern Botswana. Nevertheless, this data is necessary for targeting surveillance and control measures in livestock production at national level. Methods: In order to address this gap, we analyzed 120 blood samples from buffalo herds for the presence of common tick-borne haemoparasites causing disease in livestock, collected in two of the main wildlife areas of Northern Botswana: the Chobe National Park (CNP, n = 64) and the Okavango Delta (OD, n = 56). Results: Analysis of the reverse line blot (RLB) hybridization assay results revealed the presence of Theileria, Babesia, Anaplasma and Ehrlichia species, either as single or mixed infections. Among the Theileria spp. present, T. parva (60%) and T. mutans (37%) were the most prevalent. Other species of interest were Anaplasma marginale subsp. centrale (30%), A. marginale (20%), Babesia occultans (23%) and Ehrlichia ruminantium (6%). The indirect fluorescent antibody test (IFAT) indicated 74% of samples to be positive for the presence of T. parva antibodies. Quantitative real-time PCR (qPCR) detected the highest level of animals infected with T. parva (81% of the samples). The level of agreement between the tests for detection of T. parva positive animals was higher between qPCR and IFAT (kappa = 0.56), than between qPCR and RLB (kappa = 0.26) or the latter and IFAT (kappa = 0.15). Conclusions: This is the first report of tick-borne haemoparasites in African buffalo from northern Botswana, where animals from the CNP showed higher levels of infection than those from OD. Considering the absence of fences separating wildlife and livestock in the CNP and the higher levels of some parasite species in buffalo from that area, surveillance of tick-borne diseases in livestock at the interface in the CNP should be prioritized.

Mon projet de recherches a pour but de comprendre les interactions entre les animaux sauvages et domestiques, afin de mieux gérer leurs conséquences épidémiologiques, écologiques et socio-économiques. Mes travaux ont associé plusieurs disciplines, notamment l'écologie et l'épidémiologie, mais également la parasitologie et les sciences humaines. J'ai travaillé sur ces questions à travers deux modèles : les ongulés sauvages et le bétail en Afrique australe (1993-98 puis 2007-2014), et les espèces animales envahissantes en Nouvelle-Calédonie (2000-2006). Mes recherches ont porté sur l'écologie des ongulés sauvages et domestiques, notamment les préférences alimentaires et la sélection de l'habitat, et sur les relations entre ces interactions écologiques et la transmission de parasites (tiques) entre la faune et le bétail. En parallèle, j'ai également participé à des études sur la perception de la faune par les populations locales et la fourniture de viande de brousse, au Zimbabwe et en Nouvelle-Calédonie, et sur la prise en compte des aspects culturels et nutritionnels associés aux espèces chassées dans la mise en place de plans de gestion pour les populations locales. De retour en Afrique australe, j'ai approfondi ces recherches sur l'écologie des interfaces faune-bétail, notamment par des suivis télémétriques simultanés de buffles et bovins sympatriques, mis en relation avec les niveaux d'infestation par divers parasites et pathogènes des animaux sauvages et domestiques, tels que la tuberculose bovine, la brucellose, la fièvre aphteuse et la fièvre de la vallée du rift. J'ai également eu l'occasion de m'intéresser à un système différent des grands ongulés, en travaillant sur la circulation de la grippe aviaire entre les oiseaux sauvages et domestiques. En adoptant une démarche comparative et interdisciplinaire focalisée sur l'analyse des mécanismes de transmission des maladies, mon ambition est d'appréhender les systèmes multi-hôtes par une approche fonctionnelle qui pourrait faciliter la compréhension des mécanismes épidémiologiques complexes en jeu au sein des systèmes socio-écologiques. Ces travaux m'ont permis de publier plus de 40 articles et 16 chapitres d'ouvrages, dont 1 ouvrage en tant que co-éditeur.

Inferring the past, recent and future evolutionary history of species At the end of the last century, the renowned scientist John Avise introduced the phylogeography concept in reference to the study of the historical principles and processes that govern the geographical distribution of genealogical lineages (Avise et al. 1987; Avise 2000). Considered as a biogeography subdiscipline, phylogeography emphasizes historical aspects of the contemporary distribution of lineages (Avise & Hamrick 1996; Avise 2000; Hewitt & Butlin 1997). Widely studied, climatic changes have been shown to engender major fluctuations in the demography and distribution of wild species on an evolutionary time scale. Climatic changes (e.g. influence of Quaternary climatic fluctuations) sometimes entail long-lasting isolation of populations, subsequently leading to ecological differentiation or speciation (Lister 2004; Vrba 1995a, 1995b). These phylogeographic patterns shape the evolutionary history of contemporary taxa. Phylogeographical studies have flourished over the last few decades, especially in Europe, but not in Africa, although this continent still hosts large megafaunal communities (Barnosky et al. 2004). Understanding how African wildlife responded to climatic changes in the past facilitates the identification of biodiversity hotspots (i.e. glacial refugia), forecasting future population dynamics and developing adapted management strategies.

Avec la croissance de la population urbaine mondiale, les roles que pourraient jouer les agricultures urbaines dans les villes de demain posent question. L'Egypte, qui a connu une urbanisation tres rapide au cours du siecle dernier, semble abriter une importante diversite d'exploitations urbaines et periurbaines. La megalopole du Grand Caire, avec ses 20 millions d'habitants, ne fait pas exception et profite de la presence de fermes, dont une partie contribue a l'approvisionnement en lait de la ville. Relevant de l'economie informelle, la litterature est presque inexistante quant a leurs structures, fonctionnements, dynamiques et perspectives. Cet article decrit les principaux systemes familiaux du secteur laitier informel du Caire, afin de mieux cerner leurs contraintes et leurs opportunites. Les donnees collectees au cours d'entretiens aupres de 73 eleveurs du Caire ont permis de realiser une typologie de ces systemes en se basant sur leurs caracteristiques structurelles, techniques, familiales et economiques. Deux grandes categories ont ete identifiees : les agroeleveurs integrant agriculture et elevage, et les eleveurs hors-sol. Chacune de ces categories a ete divisee en deux types, a partir d'un gradient de la taille. Dans tous les cas, la satisfaction des besoins alimentaires familiaux a prime. Le lait de bufflonne etait le lait le plus produit et la commercialisation des surplus de lait frais passait par des circuits courts. Bien que rendant des services a la ville, ces exploitations affrontaient de nombreuses contraintes (couts eleves des intrants agricoles, pression fonciere, faible disponibilite des terres agricoles, parmi d'autres) qui remettaient en question leur subsistance a moyen terme. (Resume d'auteur)