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Preliminary study on the tick population of Benin wildlife at the moment of its invasion by the Rhipicephalus microplus tick (Canestrini, 1888)

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Background and Aim: Rhipicephalus microplus (Rm) is one of the most problematic livestock tick species in the world. Its rapid propagation and resistance to acaricides make it control difficult in the sub-region and Benin particularly. 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. This will help to design more efficient control strategy. Materials and Methods: This study was conducted from February to March 2017 in the National Parks of Benin (Pendjari and W Park) and wildfowl's assembly and selling point in Benin. Ticks were manually picked with forceps from each animal after slaughtering by hunters then stored in 70° ethanol. Collected ticks were counted and identified in the laboratory using the identification key as described by Walker. Results: Overall, seven species of ticks (Amblyomma variegatum, Boophilus decoloratus, Rm, Boophilus spp., Hyalomma spp., Rhipicephalus sanguineus, Rhipicephalus spp.) were identified on nine wild animal species sampled (Cane rat, wildcat, Hare, Doe, Cricetoma, Buffalo, Buffon Cobe, and Bushbuck and Warthog). The average number of ticks varies from 3 to 6 between animal species, 3 to 7 between localities visited, and 2 to 5 between tick species. However, these differences are statistically significant only for localities. Considering tick species and animal species, the parasite load of Rm and Rhipicephalus spp. is higher; the buffalo being more infested. The analysis of deviance reveals that the abundance of ticks observed depends only on the observed localities (p>0.05). However, the interactions between animal species and localities on the one hand and between animal and tick species on the other hand, although not significant, have influenced the abundance of ticks as they reduce the residual deviance after their inclusion in the model. Conclusion: This study reported the presence of Rm in wildlife of Benin and confirmed its role in the maintenance and spread of the parasites. It is, therefore, an important risk factor that we must not neglect in the epidemiological surveillance and ticks control strategies in the West African sub-region and particularly in Benin.
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Veterinary World, EISSN: 2231-0916 845
Veterinary World, EISSN: 2231-0916
Available at www.veterinaryworld.org/Vol.11/June-2018/18.pdf
RESEARCH ARTICLE
Open Access
Preliminary study on the tick population of Benin wildlife at the moment
of its invasion by the Rhipicephalus microplus tick (Canestrini, 1888)
Kossi Justin Adinci1, Yao Akpo2, Camus Adoligbe1, Safiou Bienvenu Adehan3, Roland Eric Yessinou1,
Akoeugnigan Idelphonse Sodé4, Guy Appolinaire Mensah3, Abdou Karim Issaka Youssao1, Brice Sinsin5 and Souaïbou
Farougou1
1. Laboratory of Research in Applied Biology, Polytechnic School of Abomey-Calavi, University of Abomey-Calavi, 01 P.O.
Box 2009, Cotonou, Benin; 2. Laboratory of Ecology, Health and Animal Production, Faculty of Agronomy, University of
Parakou, P.O. Box 123 Parakou, Benin; 3. National Institute for Scientific Research, Research Center of Agonkanmey
(CRA/INRAB), Benin; 4. Laboratory of Biomathematics and Forest Estimations Faculty of Agronomic Sciences (FSA)
University of Abomey-Calavi, 04 BP 1525, Cotonou (Bénin); 5. Department of Animal Production, Faculty of Agronomic
Sciences (FSA), University of Abomey-Calavi (Benin), 01 BP 526 Cotonou, Benin.
Corresponding author: Kossi Justin Adinci, e-mail: justinmario8@gmail.com
Co-authors: YA: yao.akpo@gmail.com, CA: adolcam83@yahoo.fr, REY: eric.yessinou@uac.bj,
SBA: adehankarim@ gmail.com, AIS: sdidelphonse@gmail.com, AKIY: iyoussao@yahoo.fr, SF: farougou@gmail.com,
BS: bsinsin@gmail.com, GAM: mensahga@gmail.com
Received: 11-01-2018, Accepted: 17-05-2018, Published online: 25-06-2018
doi: 10.14202/vetworld.2018.845-851 How to cite this article: Adinci KJ, Akpo Y, Adoligbe C, Adehan SB, Yessinou RE,
Sodé AI, Mensah GA, Youssao AKI, Sinsin B, Farougou S (2018) Preliminary study on the tick population of Benin wildlife at
the moment of its invasion by the Rhipicephalus microplus tick (Canestrini, 1888), Veterinary World, 11(6): 845-851.
Abstract
Background and Aim: Rhipicephalus microplus (Rm) is one of the most problematic livestock tick species in the world.
Its rapid propagation and resistance to acaricides make it control difficult in the sub-region and Benin particularly. 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. This will help to design more efficient control strategy.
Materials and Methods: This study was conducted from February to March 2017 in the National Parks of Benin (Pendjari
and W Park) and wildfowl’s assembly and selling point in Benin. Ticks were manually picked with forceps from each animal
after slaughtering by hunters then stored in 70° ethanol. Collected ticks were counted and identified in the laboratory using
the identification key as described by Walker.
Results: Overall, seven species of ticks (Amblyomma variegatum, Boophilus decoloratus, Rm, Boophilus spp.,
Hyalomma spp., Rhipicephalus sanguineus, Rhipicephalus spp.) were identified on nine wild animal species sampled (Cane
rat, wildcat, Hare, Doe, Cricetoma, Buffalo, Buffon Cobe, and Bushbuck and Warthog). The average number of ticks varies
from 3 to 6 between animal species, 3 to 7 between localities visited, and 2 to 5 between tick species. However, these
differences are statistically significant only for localities. Considering tick species and animal species, the parasite load of
Rm and Rhipicephalus spp. is higher; the buffalo being more infested. The analysis of deviance reveals that the abundance
of ticks observed depends only on the observed localities (p>0.05). However, the interactions between animal species and
localities on the one hand and between animal and tick species on the other hand, although not significant, have influenced
the abundance of ticks as they reduce the residual deviance after their inclusion in the model.
Conclusion: This study reported the presence of Rm in wildlife of Benin and confirmed its role in the maintenance and
spread of the parasites. It is, therefore, an important risk factor that we must not neglect in the epidemiological surveillance
and ticks control strategies in the West African sub-region and particularly in Benin.
Keywords: Benin, Rhipicephalus microplus, ticks, wild animals.
Introduction
Ticks’ host, like all parasites host, plays an
important role in their distribution. Ticks spend almost
all their time with the host and move from one point
to another with them. Female ticks leave their host
and fall into the environment, lay eggs when they
are fully engorged. New larvae will look for another
host, and the cycle will restart [1]. Tick-borne diseases
have a significant impact on animal productivity and
cause economic losses for livestock owners. This is a
major obstacle for the livestock sector development in
Africa and Benin, in particular, due to the presence of
a large number of tick species including Rhipicephalus
mipcroplus (Rm), one of the most feared species [2].
The previous study has shown that Rm is a vector of
Babesia bovis, Babesia bigemina, and Anaplasma
marginale [3]. In Benin, the introduction of Rm was
largely attributed to the importation of Girolando cattle
from Brazil by the Government of Benin through the
Pafilav Project which aim was to improve local breed
milk production [4]. The first study conducted on
October 2008 in the village of Kpinnou, the main site
of Girolando cattle in Benin, indicated the presence of
Rm and the suitability of local conditions for its devel-
opment [5]. As stated by different findings, this tick
species has rapidly spread all over the country [6].
Ticks collection and identification from domestic ani-
mals were done several times for research purposes.
Copyright: Adinci, et al. Open Access. This article is distributed under
the terms of the Creative Commons Attribution 4.0 International
License (http://creativecommons.org/licenses/by/4.0/), which
permits unrestricted use, distribution, and reproduction in any
medium, provided you give appropriate credit to the original
author(s) and the source, provide a link to the Creative Commons
license, and indicate if changes were made. The Creative Commons
Public Domain Dedication waiver (http://creativecommons.org/
publicdomain/zero/1.0/) applies to the data made available in this
article, unless otherwise stated.
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Wildlife is often pointed to act as a reservoir
of tick-borne disease for domestic animals and,
vice versa [7-9]. Some studies confirm this percep-
tion for some diseases (severe acute respiratory syn-
drome, bird flu) [10-12]. For pastoralist, wildlife can
be the cause of economic disasters when the survival
or profitability of the domestic herd is threatened by
epizootics or endozooties in which the fauna acts as a
carrier, reservoir, or intermediate host [13]. However,
no investigation has yet been done on wild species
following the identification and spread of Rm, which
stands out for its resistance to common acaricides and
is a real problem for ruminant farms in Benin [14].
Studies related to the identification of the tick
population of Benin’s wildlife are, therefore, neces-
sary. These will make it possible to check the pres-
ence of this new species tick in the wildlife of Benin.
Furthermore, they will allow to have a good knowl-
edge of the acarological environment of this tick and
to take it to account in the strategies of control.
Materials and Methods
Ethical approval
The samples taken during the present study knew
no ethical requirements. In fact, these samples were taken
from animals slaughtered by legal and illegal hunters.
Study area
This study was conducted in Southern, Central, and
Northern Benin located in the intertropical zone between
parallels 6 ° 30 ‘ and 12 ° 30’ of north latitude on the
one hand and meridians 1° and 3° 40’ of east longitude,
on the other hand, Benin covers an area of 112,622 km2.
The relief is slightly uneven, consisting of 2 plains and
plateaus whose average altitude does not exceed 200
meters. The highest region (Atacora) where many riv-
ers take their source from (Alibori, Mekrou…) is located
at the northwestern part of the country (Alibori and
Mekrou) Benin has three main climatic zones as follow:
• Thenorthernpartischaracterizedby asemi-arid
Sudanese climate beyond latitude 10° N with a
unimodal climatic regime (900–1100 mm of rain),
two seasons (one dry and one rainy) and a begin-
ning of saheli station, with shallow soils, often
degraded and not very fertile;
• ThecentralpartownatransitionalSudano-Guinean
climate, between 7° and 10° N parallels, with both
unimodal and bimodal climatic conditions (1000-
1200 mm of rain). It has poor colluvial soil at the
reliefs foot and the top of the undulations, with a
weak ecological situation in certain localities;
• TheSouthernpartischaracterizedbyasub-equa-
torial climate (between parallels 6° 30’ and 7° N).
It has four-seasons (two rainy and two dry sea-
sons) with fertile soils and degradation of ecolog-
ical conditions. The rainfall reaches 1500 mm.
Benin has five agro-pastoral zones: the dry
Sudanese zone with marginal pastures, the Sudanese
surplus grassland zone, the Sudano-Guinean zone
with abundant forage resources, the semi-humid zone
with agricultural vocation which becomes a zone of
breeding and the forest zone [15,16]. Benin cattle
herd is estimated at 2,166,000 head on 2015 [17],
90% of the animal is found in the Northern part of
the country. The town of Banikoara, where W Park
is located has the greatest number of cattle all over
the country. The main ruminant breeds raised in these
different agro-pastoral areas are Borgou, Somba,
Ndama, Lagunaire, Mbororo, and White Fulani
and their crossbred’s products for cattle; Djallonke
sheep, Peulh sheep, Guinean dwarf goat, Maradi red
goat, and Peulh goat for small ruminants. The whole
country is suitable for animal husbandry, except a
small area in the northern and southern part of the
country [18].
Sampling sites
In southern and central Benin, samples were taken
at the grouping and selling points of wildfowl in the
commune of Kpomasse, Dassa-Zoume, Agbanhizoun,
and Zogbodome, respectively. In northern Benin,
sampling was performed in the two national parks
(W Park and Pendjari Park). These sampling sites are
illustrated in Figure-1.
Materials
To achieve our goal, we used a stereo-micro-
scope (Zeiss Stemi 2000) with a 60× resolution, a
microscope with a 100× resolution, a Geographic
Position System, 70° of ethanol, plastic bottles, pliers,
a pencil, and adhesive papers, A4 papers.
Animal species and period of study
Ticks were collected from February to March
2017 on 9 wild animal species that were freshly
slaughtered and visibly infested (Table-1). Sampling
area selection was made randomly.
Ticks collection
Ticks were manually picked with forceps from
each animal after they were slaughtered by hunters.
These ticks were kept in different vials of 100 ml con-
taining 70° of ethanol. One vial is used per animal
species. At the end of each sampling, a tag made of
A4 paper with the necessary information (date of col-
lection, sampling area, and animal species sampled)
was directly inserted into each vial before it was com-
pletely closed.
Figure-1: Sampling sites.
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Ticks identification
Ticks identification was made at the laboratory
based on the identification key as described by Walker
et al. [19] using a binocular loupe. The genus and spe-
cies of each tick examined were recorded.
Statistical analysis
The average number of ticks was calculated
for the different factors including localities, animal
species, and tick species. The same parameters were
calculated for localities, and animal species for each
species of tick observed. Then these averages were
tested using a Kruskal–Wallis test. Histograms were
also constructed to highlight the proportion of dif-
ferent stages of tick development per animal species
and localities. In addition, the proportion of each tick
species was calculated by animal species and local-
ity to assess the importance of its prevalence. Finally,
to evaluate the effect of the factors studied on tick’s
abundance, the data were adjusted to the Poisson
model since the latter come from counts. All analyses
were done with R Core Team version 3.2.2 software
(Vienna, Austria).
Results
Comparison of average number of ticks according to
factors levels
The average number of ticks varies from 3 to
6 between animal species, 3 to 7 between visited
localities, and 2 to 5 between tick species (Table-1).
However, these differences are statistically significant
only for localities (Table-1). With regard to animal
species, the highest average number of ticks is obtained
on doe (Cervus elaphus) and Wildcat (Felis silvestris)
in the locality of Adomougon (Table-1). Considering
simultaneously localities and tick species, Rm has
the highest average number in the locality of Mekrou
(Table-2). Taking into account tick species and animal
species, the parasite load of Rm and Rhipicephalus
spp. is higher and Buffalo is the most infested animal
(Table-3).
Variation in tick number by sex and development
stage
Tick number collected within different localities
and on different animal species was counted by sex
and development stage. Overall, the results reveal that
in all the localities and for all animal species consid-
ered, female ticks are the most prevalent (Figure-2a-b).
Larvae or nymphs are less observed or almost absent in
certain species such as the cricetoma (Gambia rat) and
buffalo cobe. Table-4 shows that only Rhipicephalus
sanguineus is found on doe (C. elaphus) whereas only
Rhipicephalus spp. is found on wildcat (F. silvestris).
The other animal species are infested by several tick
species; however, ticks belonging to Boophilus and
Rhipicephalus genus are predominant.
Adjustment of the data to Poisson model
The deviance analysis table reveals that the
abundance of ticks observed depends only on local-
ities (p>0.05) (Table-5). However, the interactions
between animal species and localities on the one hand
and between animal and tick species on the other hand,
although not significant, can influence the abundance
of ticks as they reduce the residual deviance after their
integration into the model.
Discussion
Previous studies on domestic animal particu-
larly cattle have shown the existence of for genus
of ticks (Amblyomma, Boophilus, Rhipicephalus,
and Hyalomma) in Benin. Meanwhile, these works
revealed that September, October, November, June,
July, and August are favorable to the proliferation of
ticks and the months of February and March are peri-
ods of low abundance [20-22]. The results of our work
on wild animals at Northern, central, and southern
Table-1: The selected animal species.
Scientific name Common
name
Number of
animals
Thryonomys swinderianus Cane rat 14
Felis silvestris Wildcat 1
Lepus spp. Hare 26
Cervus elaphus Doe 2
Cricetomys gambianus Cricetoma 10
Syncerus caffer planiceros Buffalo 7
Kobus kob Buffon Cobe 2
Tragelaphus scriptus Bushbuck 8
Phacochoerus aethiopicus Warthog 3
Total 73
Table-2: Average number of ticks and standard error per factor.
Animal species Localities Ticks species
Modalities Avg. SE Modalities Avg. SE Modalities Avg. SE
Wildcat 6.00a- Adomougon 7.75a2.17 Av 5.00a3.00
Cane rat 5.00a0.89 Hounkpogon 4.11ab 0.48 Bd 2.00a0.00
Doe 6.00a- Koncombri 4.22ab 0.88 Rm 5.33a0.91
Buffalo 4.78a1.09 Mekrou 4.57ab 1.11 Bsp 3.75a0.75
Buffon cobe 2.50a0.50 Porga 2.40b0.24 Hsp 3.17a0.31
Cricetoma 4.00a0.55 Segbohoue 5.50ab 0.96 Rsa 5.57a1.65
Bushbuck 3.63a0.68 Tegon 4.00ab 1.14 Rsp 4.58a0.57
Hare 5.50a1.45 - -
Warthog 3.50a0.65
Prob. 0.636 0.075 0.191
Av=Amblyomma variegatum, Bd=Boophilus decoloratus, Rm=Rhipicephalus microplus, Bsp=Boophilus spp.,
Hsp=Hyalomma spp, Rsa=Rhipicephalus sanguineus, Rsp=Rhipicephalus spp. Prob.=Probability related to the
significance of the Kruskal–Wallis test at the 5% threshold, Avg.=Average, SE=Standard error. Averages with same
letters within the same column are not significantly different at 5%
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Table-3: Average number of ticks and standard error by location and tick species.
Localities Statistics Tick species
Av Bd Rm Bsp Hsp Rsa Rsp
Adomougon Avg. - - 7 6 - 14 4
SE - - - - - - -
Hounkpogon Avg. - - 3.5 - 3 4 6
SE - - 0.5 - 0 1 0
Koncombri Avg. - 2 8 3 3 - 4.75
SE - - - - 1 - 1.55
Mekrou Avg. 2 2 8.5 3 4 - 4
SE - - 1.5 - - - -
Porga Avg. - 2 2.5 - 3 - 2
SE - - 0.5 - - - -
Segbohoue Avg. - - 4 - - 6 6
SE - - - - - 2 -
Tegon Avg. 8 - - 3 - 1 4
SE - - - - - - 0
Prob. 0.317 - 0.354 0.391 0.900 0.867 0.403
SE=Standard error, Prob.=Probability of the significance of the Kruskal–Wallis test at only 5%. Avg.=Average,
Av=Amblyomma variegatum, Bd=Boophilus decoloratus, Rm=Rhipicephalus microplus, Bsp=Boophilus spp.,
Hsp=Hyalomma spp., Rsa=Rhipicephalus sanguineus, Rsp=Rhipicephalus spp.
Table-5: Full model deviance analysis table.
SSV Df Deviance Resid. Df Resid. Dev Pr(>χ)
Null 42 57.31
Species 8 7.80 34 49.51 0.453
Localities 6 17.74 28 31.77 0.007**
Ticks 6 6.76 22 25.01 0.344
Species: Localities 7 9.56 15 15.45 0.214
Species: Ticks 9 11.02 6 4.43 0.274
Localities: Ticks 6 4.42 0 0 0.619
Species: Localities: Ticks 0 0 0 0 -
**Significant at the 5% threshold
Table-4: Average number of ticks and standard error per tick and animal species.
Animal species Statistics Tick species
Av Bd Rm Bsp Hsp Rsa Rsp
wildcat Avg. - - - - - - 6
SE - - - - - - -
Cane rat Avg. 8 - - - 3 4 5
SE - - - - - - 1
Doe Avg. - - - - - 6 -
SE - - - - - - -
Buffalo Avg. 2 2 7 - 3.5 - 9
SE - 0 2.08 - 0.5 - -
Buffon cobe Avg. - 2 - - - - 3
SE - - - - - - -
Cricetoma Avg. - - - 6 3 3 4
SE - - - - - - 0
Bushbuck Avg. - - 4 3 - - 3.5
SE - - 1.53 - - - 0.96
Hare Avg. - - 5 3 - 6.5 -
SE - - 1 - - 2.9 -
Warthog Avg. - - - 3 3 - 5
SE - - - - 1 - -
Prob. 0.317 - 0.2101 0.391 0.654 0.199 0.495
SE=Standard error, Prob.=Probability of the significance of the Kruskal–Wallis test at only 5%. Av=Amblyomma
variegatum, Bd=Rhipicephalus decoloratus, Rm=Rhipicephalus microplus, Bsp=Boophilus spp., Hsp=Hyalomma spp.,
Rsa=Rhipicephalus sanguineus, Rsp=Rhipicephalus spp.
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Benin also showed the presence of the four geniuses
of ticks previously found on domestic animals. Morel
[23] reported the presence of four kinds of ticks
on wild animals in Benin including Amblyomma,
Boophilus Rhipicephalus, and Haemaphysalis. The
latter, specific to carnivores, was not identified in this
study.
Among the ticks of Boophilus genius, we have
identified three species, namely Boophilus microplus,
Boophilus decoloratus, and Boophilus spp. [24] iden-
tified Boophilus geigyi in Benin on hartebeest and
in Niger (north of W park) on hartebeest and roan.
It has also been identified in Senegal on Luzarches
hartebeest and then the bushbuck and warthog in
the Niokolo-koba National Park. In the North East
of Central Africa, the work of Thal [25] also men-
tioned the presence of this species on hartebeest and
roan. Indeed, according to this author, it is the only
Boophilus that could be found on wild ungulates in
West Africa. However, although our samples were
taken from ungulates such as C. elaphus, Syncerus
caffer planiceros, Kobus kob, Tragelaphus scrip tus,
and Phacochoerus aethiopi cus, this species has
not been identified. Its absence could be linked to a
mutation phenomenon leading to the appearance of
Rm. This phenomenon was already described in East
Africa where Rm replaced the other Rhipicephalus
species [26]. The highest presence Rm in the hunting
camp of the Mekrou and Koncombri can be explained
by the fact that there are next to Burkina Faso.
Moreover, the presence of water table next to W park
hunting area in Popoman attract transhumant animals
from Burkina-Faso and could explain the strong rep-
resentation of Rm in the Mekrou area. Indeed, these
camps are located at the Benin-Burkina border where
there is a large movement of live cattle from Burkina
to Benin through livestock trade. This is corroborated
by recent findings that revealed the presence of this
tick in Benin and Benin-Burkina Faso border [27].
However, the presence of B. decoloratus men-
tioned in this study does not confirm the results of
Lamontellerie [28] who state that B. decoloratus is a
tick of arid environments an only found on livestock
and never on wild ungulates. Several authors have
reported its presence on cattle in Benin [23,29]. Its
presence on wild ungulates may be due to the possibil-
ity of being transported on long distances by the host
from one environment to another as it development
cycle is monophasic.
Altogether, two species of Boophilus were iden-
tified in our study. The undefined (Boophilus spp.)
species may be originated from the different crossings
that occur, nowadays, between Boophilus species [7].
One species of Rhipicephalus (R. sanguineus)
and some undefined species (Rhipicephalus spp.)
were identified. R. sanguineus is collected from doe
(C. elaphus), cricetoma (Cricetomys gambianus), hare
(Lepus spp.), and cane rat (Thryonomys swinder ianus)
in areas located in Central and Southern Benin.
However, Rhipicephalus spp. is present in all the
prospected localities. The absence of R. sanguineus in
this study in the parks may be related to the prohibi-
tion of hunting that would have limited dog access to
the parks. In fact, illegal hunters are often accompa-
nied by their dogs, which constitute the main host of
R. sanguineus in the tropics and subtropics as reported
by Fahmy et al. [30]. A high probability of dissemina-
tion of this tick on the natural route by these dogs and
thus an infestation of wild animals is possible. This
has been proven by the work of Smith et al. [31].
Amblyomma tick is widespread in Africa, and its
hosts are domestic and wild ruminants such as buf-
faloes, cattle, sheep, and goats [32]. However, they
are able to infest others animals species. This is the
case in our study where Amblyomma variegatum was
found on cane rats (T. swinderianus).
The buffalo hosts two specific ticks, Amblyomma
splendidum and Rhipicephalus cliffordi; both species
were identified in Ivory Coast, and A. splendidum
only in central Benin [23].
None was identified in western, central, and east-
ern Burkina-Faso although the number of buffalo one
by the country [23].
Similarly, Barre [33] found this tick, at the adult
stage, on Caribbean and Guadeloupe dog’s, where it
was introduced 150 years ago. Our results confirm the
great variability of hosts susceptible to be infested by
the ticks of the Amblyomma genus.
Figure-2: Proportions of the following tick stages (a) localities and (b) animal species. Localities: (Adom=Adomougon,
Houn=Hounkpogon, Konc=Koncombri, Mekr=Mekrou, Porg=Porga, Segb=Segbohoue, and Tego=Tegon). Animals:
(Alu=Wild cat, Aul=Cane rat, Bic=Doe, Buf=Buffalo, Cob=Buffon cobe, Cri=Cricetoma, Gui=Bushbuck, Lie=Hare, and
Pha=Warthog).
b
a
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Hyalomma spp. populations have been iden-
tified on C. gambianus, T. swinderianus, S. caffer,
and P. aethiopicus. This demonstrates its ability to
infest a diversity of hosts. These results are in con-
cordance with those obtained by Morel [23]. Indeed,
Hyalomma ticks are generally found on wild ungulates
and rodents. The same author reports the presence of
Hyalomma nitidum in Central African Republic where
it was collected on Buffalo, Antelope, Buffalo Cob,
and warthog. It is also known in Senegal and Benin.
Of all these species, it should be noted that the
proportion of nymph and larva is very low or almost
absent. Indeed, previous work carried in the same
areas and during the same month’s revealed low abun-
dance of nymph and larva [34]. This observation can
be explained by several factors such as the height
of the animals considered, targeted animals are old,
and old animals are big in size what make does not
favor nymph and larva to attach to them; the climate:
February and March are hot and larva and nymph
are more sensitive to heat than adults. Moreover,
this period is the most favorable for the availability
of wildfowl, and illegal hunters use bushfires to find
wildfowl. As a result, these bushfires, kill imma-
ture ticks hidden in the environment. According to
Verdonck [35], immature survival is very dependent
on humidity during the hot season; the abundance of
Rm, for example, begins to decrease at the end of the
rainy season. Likewise, tick activity varies according
to species and climatic conditions [36]. However, the
massive presence of ticks does not always correspond
to the rainiest months. Farougou et al. [22] showed a
low correlation between rainfall and number of ticks
collected. This result can be explained by the fact that
some ticks appear before the rainy season. The find-
ing may also be related to genus and stage of devel-
opment that persist in moisture and sometimes other
sources of moisture at the vegetation level. Similarly,
Fahmy et al. [30] showed that Rm can grow in warm
and humid regions, B. decoloratus in dry and cold
areas, and Boophilus annulatus can survive in areas
suitable both for Rm and B. decoloratus. This fact has
also been confirmed by several researchers [37,38].
Madder et al. [27] and Muhimuzi et al. [39] also
reported that B. annulatus and B. geigyi might share
the same habitats associated with woods and forests
and favor similar environmental requirements as well.
In summary, during this cross-sectional study
on wild animals in Benin, seven species of ticks were
identified including Rm on buffalo, the bushbuck, and
the hare. Although the number of animals surveyed and
the number of ticks taken are low for specific reasons
related to the low parasite load of the animals encoun-
tered, the reluctance of some illegal hunters and the
limited number of legal hunters with a hunting license
at the level of national parks. 24 tick species have
been recorded on wild animals in Upper Volta [23]; In
the Democratic Republic of Congo, three species of
ticks were identified on natural grasslands, including
Rhipicephalus appendiculatus, B. decoloratus, and
Haemaphysalis Leachi Leachi [39]. The lower num-
ber of tick collected in our case is due to the reluctance
of some hunters to allow ticks collection from their
animals. Moreover, the number of hunters that can be
survey is also limited as few hunters own a hunting
license.
Conclusion
This study shows that Rm is established in the
wildlife of Benin. Its presence confirms the reservoir
role and maintenance that wildlife plays in the spread
of parasites. Wildlife is, therefore, an important risk
factor that should not be neglected in the epidemio-
logical surveillance and tick control strategies partic-
ularly Rm in Benin and the West African sub-region.
Thus, it is important to involve in the programs of pro-
tection of the faunistic reserves the control of ticks in
particular and a sanitary management of wildlife in
general.
Authors’ Contributions
KJA; BS, GAM; YA, and SBA have partici-
pated in developing the protocol, the sample of ticks
and in drafting the manuscript. REY participated in
the identification of ticks and the development of
the database. CA contributed to the translation of the
manuscript. AKIY; SF and AIS supervised the anal-
ysis of the statistical results and the correction of the
manuscript. All authors have read and approved the
final manuscript.
Acknowledgments
We thank the authorities of the Wildlife Reserves
Management National Center (CENAGREF) for per-
mitting us to access to national parks. We are grateful
to Prof Farougou Souaïbou and our collaborators of
URBPSA/laboratory of acarology for their help. This
project is self-funded.
Competing Interests
The authors declare that they have no competing
interests.
References
1. Barré, N., Uilenberg, G. (2010) Propagation de parasites
transportés avec leurs hôtes: Cas exemplaires de deux
espèces de tiques du bétail. Rev. Sci. Tech. Off. Int. Epiz.,
29(1): 135-147.
2. De Clercq, E.M. (2013) Assessment of the Ecological
Niche of Rhipicephalus microplus in West Africa. Thesis
of Master in Bio-science Engineering: Forest and Nature
Management. p1.
3. Jonsson, N., Bock, R. and Jorgensen, W. (2008) Productivity
and health effects of anaplasmosis and babesiosis on Bos
indicus cattle and their crosses, and the effects of differ-
ing intensity of tick control in Australia. Vet. Parasitol.,
155(1- 2): 1-9.
4. Lempereur, L., Geysen, D., Madder, M. (2010) Development
and validation of a PCR–RFLP test to identify African
Rhipicephalus (Boophilus) ticks. Acta Trop., 114: 55-58.
5. Madder, M., Thys, E., Achi, L., Toure, A. and De Deken, R.
(2011) Rhipicephalus (Boophilus) microplus: A most suc-
cessful invasive tick species in West-Africa. Exp. Appl.
Acarol., 53(2): 139-145.
6. De Clercq, E.M., Vanwambeke, S.O., Sungirai, M.,
Adehan, S., Lokossou, R. and Madder, M. (2012)
Geographic distribution of the invasive cattle tick
Veterinary World, EISSN: 2231-0916 851
Available at www.veterinaryworld.org/Vol.11/June-2018/18.pdf
Rhipicephalus microplus, a country-wide survey in Benin.
Exp. Appl. Acarol., 58: 441-452.
7. Keck, F. (2013) Santé animale et santé globale: La grippe
aviaire en Asie. Rev. Tiers Monde, 215(3): 35-52.
8. Ariane, P. (2014) Rôle de la Faune Sauvage dans
le Système Multi-hôtes de Mycobacterium bovis
et Risque de Transmission Entre Faune Sauvage et
Bovins: Etude Expérimentale en Côte d’Or. Biologie
Animale. Université Claude Bernard, Lyon I, «NNT:
2014LYO10040».«tel-01081144».
9. Artois, M., Biteau-Coroller, F., Rossi, S. and Hars, J. (2002)
La surveillance et le contrôle des maladies infectieuses de la
faune sauvage en France et en Europe. Bull. Soc. Méd. Vét.
Pratique, 86: 36-51.
10. Bengis, R.G., Leighton, F.A., Fischer, J.R., Artois, M.,
Mörner, T. and Tate, C.M. (2004) The role of wildlife in
emerging and re-emerging zoonoses. Rev. Sci. Tech. Off. Int.
Epiz., 23(2): 497-511.
11. Hestvik, G., Warns-Petit, E., Smith, L.A., Fox, N.J.,
Uhlhorn, H., Artois, M., Hannant, D., Hutchings, M.R.,
Mattsson, R., Yon, L. and Gavier-Widen, D. (2015) The sta-
tus of tularemia in Europe in a one-health context: A review.
Epidemiol. Infect., 143: 2137–2160.
12. Vagneron, F. (2015) Surveiller et s’unir: Le rôle de l’OMS
dans les premières mobilisations internationales autour d’un
réservoir animal de la grippe. RAC, 9(2): 139-162.
13. Michel, A.L. and Bengis, R.G. (2012) ‘The African buffalo:
A villain for inter-species spread of infectious diseases in
southern Africa. Onderstepoort. Online J. Vet. Res., 79(2),
Article ID: #453, 5 Pages.
14. Eric, Y.R., Akpo, Y., Adoligbe, C., Adinci, J., Assogba, M.N.,
Koutinhouin, B., Abdou Karim, I.Y. and Farougou, S.
(2016b) Resistance of tick Rhipicephalus microplus to aca-
ricides and control strategies. J. Entomol. Zool. Stud., 4(6):
408-414.
15. ANOPER Benin, (2014) Current situation of livestock and
ruminant farmers in Benin. 10p.
16. Marc, M. (2015) Breeders’ challenges: the case of Benin
in West Africa. SOS Hunger/Farming Dynamics no36, 2p.
https://www.sosfaim.org/be/publication.
17. Countrystat (2018) Élevage: Total des Effectifs D’animaux
Vivants par Annee, Niveau Administratif 2, Produits.
Available from: http://www.countrystat.org/home.
aspx?c=benetta= 053SPD135ettr=-2. Last accessed on
14-04-2018. 
18. Wint, W. and Robinson, T.P. (2007) Gridded Livestock of
the World. FAO, Rome.
19. Walker, A.R., Bouattour, A., Camicas, J.L., Estrada–
Peña, A., Horak, I.G., Latif, A.A., Pegram, R.G. and
Preston, P.M. (2007) Ticks of Domestic Animals in Africa:
A Guide to Identification of Species. © The University of
Edinburgh, p221.
20. Vercruysse, J., Lafia, S. and Camicas, J.L. (1982) Les tiques
(Amblyommidae) parasites des bovins en republique pop-
ulaire du Bénin. Rev. Elev. Med. Vet. Pays Trop., 35(4):
361-364.
21. Farougou, S., Tassou, A.W., Tchabode, M., Kpodekon, M.,
Boko, C. and Youssao, A.K.I. (2007b) Ticks and hemo-
parasites in cattle in the north of Benin. RMV, 158(8-9):
463-467.
22. Farougou, S., Kpodekon, S.M., Adakal, H. and Sagbo, R.
(2007a) Seasonal abundance of ticks (Acari: Ixodidae)
infesting sheep in the southern area of Benin. RMV, 12(158):
627-632.
23. Morel, P.C. (1978) Tiques d’animaux sauvages en Haute-
Volta. Rev. Elev. Méd. Vét. Pays Trop., 31(1): 69-78.
24. Hoffmann, G. and Lindau, M. (1971) Zecken an Nutz-und
Wildtieren in Niger. J. Appl. Entomol., 69(1-4), 72-82.
25. Thal, J.A. (1972) Similar Diseases to Plague: Study and
Control. Ndele, Central African Republic. FAO/UNDP
CAF Project 13. Final Report. Maisons- Alfort, E. M. V. T.,
37 p4.
26. Estrada-Pena, A., Bouattour, A., Camicas, J.L.,
Guglielmone, A., Horak, L., Jongejan, F., Latif, A.A.,
Pegram, R.G. and Walker, A.R. (2006) The known dis-
tribution and ecological preferences of the tick subge-
nus Rhipicephalus (Acari: Ixodidae) in Africa and Latin
America. Exp. Appl. Acarol., 38: 219-235.
27. Madder, M., Adehan, S., De Deken, R., Adehan, R. and
Lokossou, R. (2012) New foci of Rhipicephalus microplus
in West Africa. Exp. Appl. Acarol., 56: 385-390.
28. Lamontellerie, M., (1966) Tiques (Acarina, Ixodoidea) de
Haute-Volta. Bull. L’IFAN A, 28: 597-642.
29. Sungirai, M. (2012) Identification of the Four Rhipicephalus
(Boophilus) Ticks Species and their Hybrids from Benin:
Morphology Versus Genetics. ITMA-MSTAH Thesis,
No. 179, p55.
30. Fahmy, M.A.M., Arafa, M.S., Mandour, A.M. and
Sema, A.A.A. (1981) Survey of hard tick (Ixodidae) infest-
ing domestic animals in Assuit Governorate, Upper Egypt.
Acta Parasitol. Polonica, 28(9): 91-96.
31. Smith, F.D., Ballantyne, R., Morgan, E.R. and Wall, R.
(2011) Prevalence and risk associated with tick infestation
of dogs in Great Britain. Med. Vet. Entomol., 25: 377-384.
32. Dougnon, T.J., Adéhan, S., Anago, E., Houessionon, J. and
Farougou, S. (2015) In vitro effect of the ethanolic extract of
Tephrosia vogelii on Rhipicephalus sanguineus in Abomey-
Calavi. Avicenna J. Phytomed., 5(3): 247-259.
33. Barre, N. (1989) Biology and Ecology of the tick
Amblyomma Variegatum (Acarina: Ixodina) in Guadeloupe
(French West Indies). Thèse de Doctorat en Sciences,
Université de Paris Sud, p268.
34. Farougou S., Kpodékon M., Tchabodé D.M, Youssao, A.K.I.,
et Boko, C. (2006) Abondance saisonnière des tiques (Acari:
Ixodidae) parasites des bovins dans la zone soudanienne du
Bénin: Cas des départements de l’Atacora et de la Donga.
Ann. Méd. Vét., 150: 145-152.
35. Verdonck, M.L. (2013) Assessment of the Ecological Niche
of Rhipicephalus (Boophilus) microplus in West Africa.
Universiteit Gent, Faculty of Bio-Science Engineering.
36. Estrada-Peña, A. (2015) Ticks as vectors: Taxonomy, biol-
ogy and ecology. Rev. Sci. Tech. Off. Int. Epiz., 34(1): 53-65.
37. Sutherst, R.W. (1987) The dynamics of hybrid zones
between tick (Acari) species. Int. J. Parasitol., 17(4):
921-926.
38. Lynen, G., Zeman, P., Bakuname, C., Di, G.G., Mtui, P.,
Sanka, P. and Jongejan, F. (2008) Shifts in the distributional
ranges of Rhipicephalus ticks in Tanzania: Evidence that a
parapatric boundary between B. microplus and B. decolor-
atus follows climate gradients. Exp. Appl. Acarol., 44(2):
147-164.
39. Muhimuzi, A.B., Ombeni, B.E., Chishibanji, B.W. and
Masunga, M.B. (2014) The infestation of natural grasslands
by ticks in groups of Bugorhe and Irhambi-katana area in
the province of South Kivu, Democratic Republic of Congo.
Int. J. Innovat. Appl. Stud., 9(4): 1966.
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... The study was carried out in Benin. With a population of 10,008,749 [23], Benin is located in the intertropical zone between parallels 6°30′ North and 12°30′ North latitude, and meridians 1°East and 30°40′ East longitude [24]. With an area of 114,763 km 2 , Benin is bordered in the north by the Niger River in the northwest by Burkina Faso, in the west by Togo, in the south by the Atlantic Ocean and in the east by the Nigeria (Fig. 1). ...
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Background: Pigeonpea is a multipurpose food legume that contributes to food security in Benin. However, its production declined and some landraces are being threatened to disappear. For establishment of conservation and breeding programs previous ethnobotanical surveys on pigeonpea were done in Benin but restricted to south and central regions. Knowing that in past years, pigeonpea landraces were introduced in northern Benin for soil fertility management, it is therefore important to evaluate the diversity of this legume in this region. Exhaustive documentation of pigeonpea diversity grown in the Republic of Benin is necessary for effective breeding and conservation programs. Therefore, this study aimed to document genetic diversity of pigeonpea, across the agro-ecological zones of the Republic of Benin for its promotion and valorization. Methods: 500 producers of pigeonpea belonging to thirteen sociolinguistic groups were selected through 50 villages. Data were collected using methods and tools of participatory research appraisal. Folk nomenclatures, taxonomy of pigeonpea and seed system were investigated. The distribution and extent of pigeonpea landraces were evaluated using the Four Square Analysis method. A comparative analysis of pigeonpea uses categories, production systems, pigeonpea production constraints, famers’ preference criteria and participative evaluation for existing landraces across agro-ecological zones was done. Result: Folk nomenclature and taxonomy were mainly based on seed coat colour and size. Seven pigeonpea use categories were recorded including sacrifice, grain processing and fertilization. The results showed that the pigeonpea seed system is informal. Based on seed characteristics, fifteen landraces were recorded with seven new landraces. The Sudano-Guinean zone contained the highest number (11) of landraces. The average number of landraces per village was 2.7. A high rate of landraces threatened to disappear was observed across the ecological zones. Ten constraints are known affecting pigeonpea production in Benin with pests and diseases as the most important in all agro-ecological zones. This study revealed that pigeonpea cultivation is increasing in the Sudanian zone. Varieties to be produced must be selected on the basis of 11 criteria among them precocity and resistance to pests and diseases, in the three ecological zones and adaptability to any type of soil in the Sudanian zone were the most important. The participatory evaluation revealed the existence of a few performing cultivars. Conclusions: Our results show that to implement a pigeonpea genetic conservation program in Benin, it would be necessary to take into account the diversity, production constraints and criteria of varietal preference, which varied according to agro-ecological zones. In situ and ex situ conservation strategies are important to preserve pigeonpea landraces. Morphological and molecular characterizations of identified cultivars are highly recommended to help select suitable varieties for breeding programs.
... The study was carried out in Benin. With a population of 10,008,749 [23], Benin is located in the intertropical zone between parallels 6°30' North and 12°30' North latitude, and meridians 1° East and 30°40' East longitude [24]. With an area of 114,763 km², Benin is bordered in the north by the Niger River in the northwest by Burkina Faso, in the west by Togo, in the south by the Atlantic Ocean and in the east by the Nigeria (Figure 1). ...
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Full-text available
Background: Pigeonpea is a multipurpose food legume crop that contributes to food security in the Republic of Benin. For the establishment of conservation and breeding programs, previous ethnobotanical surveys on pigeonpea were done in Benin but restricted to south and central regions. In previous years, pigeonpea landraces were introduced in northern Benin for soil fertility management; it is therefore important to evaluate the diversity in this legume in this region. Exhaustive documentation of pigeonpea diversity grown in the Republic of Benin will be necessary for effective breeding and conservation programs. Therefore, the aim of this study was to document genetic diversity of pigeonpea, across the agro-ecological zones of the Republic of Benin for its promotion and valorization. Methods: A total of 500 pigeonpea farmers representing thirteen sociolinguistic groups were selected from 50 villages. The data were collected using methods and tools of participatory research appraisal. Folk nomenclatures, taxonomy of pigeonpea and seed system were investigated. The distribution and extent of pigeonpea landraces were evaluated using the Four Square Analysis method. A comparative analysis of pigeonpea use categories production systems, production constraints, famers’ preference criteria and participative evaluation for existing landraces across agro-ecological zones was done. Result: Folk nomenclature and taxonomy were mainly based on seed coat colour and size. Seven pigeonpea use categories were recorded including sacrifice, grain processing and fertilization. The results showed that the pigeonpea seed system is informal. Based on seed characteristics, fifteen landraces were recorded including seven new landraces. The Sudano-Guinean zone contained the highest number (11) of landraces. The average number of landraces per village was 2.7. A high rate of landraces facing threat of disappearance was observed across the ecological zones. Ten constraints are known to affect pigeonpea production in Benin, with pests and diseases as the most critical in all agro-ecological zones. This study revealed that pigeonpea cultivation is increasing in the Sudanian zone. Varieties to be produced must be selected based on 11 criteria which included precocity and resistance to pests and diseases in the three ecological zones and adaptability to any type of soil in the Sudanian zone. The participatory evaluation revealed the existence of a few performing cultivars. Conclusions: Our results revealed that implementation of a pigeonpea genetic conservation program in Benin must take into account the diversity, production constraints and varietal preference, which varied according to agro-ecological zones. In situ and ex situ conservation strategies are important to preserve pigeonpea landraces. Morphological and molecular characterizations of identified cultivars are highly recommended to help select suitable varieties for breeding programs.
... The study was carried out in Benin. With a population of 10,008,749 [23], Benin is located in the intertropical zone between parallels 6°30′ North and 12°30′ North latitude, and meridians 1°East and 30°40′ East longitude [24]. With an area of 114,763 km 2 , Benin is bordered in the north by the Niger River in the northwest by Burkina Faso, in the west by Togo, in the south by the Atlantic Ocean and in the east by the Nigeria (Fig. 1). ...
Preprint
Background: Pigeonpea is a multipurpose food legume that contributes to food security in Benin. However, its production declined and some landraces are being threatened with disappearance. For establishment of conservation and breeding programs previous ethnobotanical surveys on pigeonpea were done in Benin but restricted to south and central regions. Knowing that pigeonpea is also grown in northern Benin, and that the varieties cultivated in this region can show agronomic performances, it is therefore important to evaluate the diversity of this legume in this region. However, an exhaustive documentation of pigeonpea diversity grown in Benin Republic are necessary for effective breeding and conservation programs. Therefore, this study aimed to document genetic diversity of pigeonpea, across the agro-ecological zones of Benin Republic for its promotion and valorization. Methods: 500 producers of pigeonpea belonging to thirteen sociolinguistic groups were selected through 50 villages. Data were collected using methods and tools of participatory research appraisal. Folk nomenclatures, taxonomy of pigeonpea and seed system were investigated. The distribution and extent of pigeonpea landraces were evaluated using Four Square Analysis method. A comparative analysis of pigeonpea uses categories, production systems, pigeonpea production constraints, famers’ preference criteria and participative evaluation for existing landraces across agro-ecological zones was done. Result: Folk nomenclature and taxonomy were mainly based on seed coat colour and size. Seven pigeonpea use category were recorded including sacrifice, grain processing and fertilization. The results showed that pigeonpea seed system is informal. Based on seed characteristics, fifteen landraces were recorded with seven new landraces. The Sudano-Guinean zone contained the highest number (11) of landraces. The average number of landraces per village was 2.7. A high rate of landraces threatened with disappearance was observed across the ecological zones. Ten constraints are known affecting pigeonpea production in Benin with pests and diseases as the most important in all agro-ecological zones. This study revealed that pigeonpea cultivation is increasing in the Sudanian zone. Varieties to be produced must be selected on the basis of 11 criteria among them precocity and resistance to pests and diseases, in the three ecological zones and adaptability to any type of soil in the Sudanian zone were the most important. The participatory evaluation revealed the existence of a few performing cultivars. Conclusions: Our results show that to implement a pigeonpea genetic conservation program in Benin, it would be necessary to take into account the diversity, production constraints and criteria of varietal preference, which varied according to agro-ecological zones. In situ and ex situ conservation strategies are important to preserve pigeonpea landraces. Morphological and molecular characterizations of identified cultivars are highly recommended to help select suitable varieties for breeding programs.
... The study was carried out in Benin. With a population size of 10 008 749 habitants [21] the Benin is located in the inter tropical zone between parallels 6° 30 ' North and 12° 30' North latitude, and meridians 1° East and 30° 40' East longitude [22]. With an area of 114,763 km², Benin is limited to the north by the Niger River in the northwest by Burkina Faso, to the west by Togo, the south by the Atlantic Ocean and to the east by the Nigeria (Figure 1). ...
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