Safiou Adehan

Background: The majority of the African population lives in rural areas and depends on agriculture for their livelihoods. To increase the productivity and sustainability of their farms, they need access to affordable yield-enhancing inputs of which parasite control is of paramount importance. We therefore determined the status of current tick species with the highest economic impact on cattle by sampling representative numbers of animals in each of seven sub-Saharan countries. Methods: Data included tick species’ half-body counts from approximately 120 cattle at each of two districts per country, collected four times in approximately 1 year (to include seasonality). Study sites were chosen in each country to include high cattle density and tick burden. Results: East Africa (Ethiopia, Uganda and Tanzania) showed overall a higher diversity and prevalence in tick infestations compared to West African countries (Benin, Burkina Faso, Ghana and Nigeria). In East Africa, Amblyomma variegatum (vector of Ehrlichia ruminantium), Rhipicephalus microplus (Babesia bovis, B. bigemina, Anaplasma marginale), R. evertsi evertsi (A. marginale) and R. appendiculatus (Theileria parva) were the most prevalent tick species of economic importance. While the latter species was absent in West Africa, here both A. variegatum and R. microplus occurred in high numbers. Rhipicephalus microplus had spread to Uganda, infesting half of the cattle sampled. Rhipicephalus microplus is known for its invasive behaviour and displacement of other blue tick species, as observed in other East and West African countries. Individual cattle with higher body weights, as well as males, were more likely to be infested. For six tick species, we found reduced infestation levels when hosts were treated with anti-parasiticides. Conclusions: These baseline data allow the determination of possible changes in presence and prevalence of ticks in each of the countries targeted, which is of importance in the light of human-caused climate and habitat alterations or anthropogenic activities. As many of the ticks in this study are vectors of important pathogens, but also, as cattle may act as end hosts for ticks of importance to human health, our study will help a wide range of stakeholders to provide recommendations for tick infestation surveillance and prevention. Graphical

A total of 5329 ticks were collected from 85 dogs in three different municipalities of Benin in West Africa. Among the species of Rhipicephalus sanguineus collected in Abomey-Calavi, the presence of a specimen with double monstrosities was revealed. The abnormal tick is a male with four pairs of legs, but the body is double lobed at the back. It has four spiracular plates, two of which are at the base at the level of the festoons and two others at the level of the fourth coxae. The specimen also has two symmetrical anal orifices, each surrounded by two adanal plates and two accessory plates, leading up to a single genital orifice. This specimen contributes to the growing database of teratological ticks.

The aim of this work was to check its presence in wildlife and to confirm the possible role of reservoir wildlife may play in the propagation of the parasite

Worldwide, cattle production is struggling to face the negative impacts caused by ticks and Rhipicephalus (Boophilus) microplus is one of the most harmful ticks for livestock. Most of the people in West Africa depend on cattle farming and subsistence agriculture. The presence of ticks on cattle is a major problem faced by smallholder farmers who fight for their livelihood. National and regional tick control programs could assist these rural communities in protecting their livelihoods against ticks and tick-borne diseases, but only if they take into account the targeted herders and their perception on cattle management and tick control. This paper aims to provide a better insight in the socio-economic characteristics of Beninese cattle farmers, and their perception on tick burden, as well as to document common tick control strategies. Different tick species and their seasonality are well understood by cattle herders. For tick control, many still use manual tick removal, especially in the north of the country. The high cost of acaricides, the lack of financial means of African farmers, and of the local stockbreeders in particular, limits the use of acaricides in livestock breeding in Benin. While aiming to increase the meat or milk production of their animals, stockbreeders who can afford it sometimes turn to an abusive use of acaricides, which might in time lead to an increase in tick resistance. This study remains one of the rare studies to report extensively on the perceptions of West African cattle herders.

| The tick Rhipicephalus microplus is an external parasite of livestock that is present in tropical and subtropical regions. It causes significant economic losses to cattle breeder directly through its destructive actions and indirectly by transmission of pathogens to livestock. In this study, we assessed the impact of Rhipicephalus microplus ticks on animal performance and identify control measures. Breeders were surveyed in Mono, Zou and Borgou departments with a rate of 60%, 63% and 67% of Peulhs on the total population of breeders’. The effect of ticks on milk production was influential in the department of Borgou where 65% of the breeders estimated that the decrease in milk production was linked to animal infestation by ticks against 46% and 41.10% respectively in the departments of Mono and Zou. A similar pattern was observed concerning the decrease in the live weight of the animals 63.75%, 58% and 45.21 %, respectively. In breeding farms, two types of products are adopted: traditional products and chemicals that are use against the ticks. As they are looking for efficient, accessible and less costly means, breeders use traditional products of control such as red oil, red oil mix with salt, black soap, seawater, plant, bush fire and also manual dipping. Chemical products used are essentially pyrethroids, amidine and phenylpyrazoles. The assessments of current study highlight that for most breeders ticks display negative impacts on livestock productivity and the current way to control are not efficient. It is important to put in place a better tick control strategy.

The invasion of West Africa by Rhipicephalus microplus during the past decade has changed the ecological situation of the agent of heartwater Ehrlichia ruminantium in this area. Before, its local vector, Amblyomma variegatum, was the most abundant tick species found on livestock. Today, the abundance of the R. microplus is one magnitude higher than that of A. variegatum in many west-African localities. We investigated the potential of this new ecological situation to impact the circulation of E. ruminantium in West Africa. Ehrlichia ruminantium infections were assessed with the specific PCR-diagnosis targeting the PCS20 region. This screening was applied on field samples of 24 R. microplus adults, on four females from a laboratory strain that had been blood-fed since larvae on one E. ruminantium-infected steer as well as on the offspring of these females at egg and larval stages. The PCR detected E. ruminantium in 29 % of the field-collected R. microplus, i.e. twice as much as reported for A. variegatum with the same protocol. Regarding the laboratory strain, the PCR-diagnosis performed showed that all females were infected and passed the rickettsia to their progeny. Sequencing of the PCR product confirmed that the maternally inherited rickettsia was E. ruminantium. According to the present findings, the invasive dynamic of R. microplus in West Africa is currently impacting the local evolutionary conditions of E. ruminantium since it offers new transmission roads such as maternal transmission in R. microplus.

A cross-section study was carried out in the Mono district in Benin to establish the different proportions of Babesia and Theleria in ticks and blood. Blood samples were collected between October and November, 2008, a period of relative abundance of ticks. The investigation covered nine herds (villages), including the farm of Kpinnou, in an agro-ecological zone where the people adhere to the same pastoral-farming tradition. In total, 756 ticks and 36 drops of blood on filter paper were taken from 36 bovines at a rate of 4 per village. Using morphological identification, identified 166 Rhipicephalus spp., 185 Amblyomma spp. and 405 Rhipicephalus (Boophilus) microplus individuals were collected, corresponding to 53.57% of the vectors. Molecular diagnosis confirmed the results of the morphological identification. Molecular methods were also used for detecting Babesia and Theileria in the bovine blood samples. Different parasites have been identified in varying prevalences: Babesia bigemina (13.89%), Babesia bovis (5.56%), Theileria mutans (22.22%), Theileria ovis (5.56%) and other Babesia species (22. 22%). No data exists so far for the district, but the results of this study are very similar to those obtained in the neighboring districts. Key words: Cattle, ticks, Rhipicephalus microplus, Babesia bigemina, Babesia bovis, Benin.