Souaïbou Farougou

Prevalence of peste des petits ruminants in the arid zone in the Republic of Niger

The study aimed to determine the prevalence of peste des petits ruminants in the arid zone (Niamey, Tillabéry and Tahoua) of the Republic of Niger. A serological survey was conducted and 519 serum samples were collected from 253 unvaccinated sheep and 266 unvaccinated goats. The sample included 340 female animals (168 sheep and 172 goats) and 160 kids and lambs (78 lambs and 82 kids). A competitive enzyme-linked immunosorbent assay yielded an overall seroprevalence of 45.0%. The prevalence in sheep was 42.0% compared with 47.9% in goats. The seroprevalence observed amongst small ruminants in Tahoua (49.8%) and Tillabéry (46.6%) was significantly higher (p = 0.001) than that observed in animals from Niamey (25.1%). It was also higher (p = 0.04) in sheep younger than two years (51.8%) than in adults (37.6%). Conversely, the seroprevalence showed no significant difference between male animals (35.8% in sheep; 50.1% in goats) and female animals (45.1% in sheep; 46.4% in goats). The prevalence of the disease observed amongst the sheep and goat populations confirms the continued danger of this disease in the areas studied. It is therefore necessary to develop strategies such as improving livestock services, providing effective vaccines and implementing a vaccination programme for an effective control of the disease in sub-Saharan Africa.

Evidence of multiple mechanisms of alphacypermethrin and deltamethrin resistance in ticks Rhipicephalus microplus in Benin, West Africa

Ticks are obligate haematophagous arthropods, causing heavy losses in affected livestock. The objective of this study is to investigate phenotypic and genotypic resistance in Rhipicephalus microplus populations from Benin. Engorged female adult ticks were collected from cattle in two districts of Benin. Bioassays, biochemical and molecular tests were carried out on these ticks to determine the phenotypic, enzymatic and genetic status of resistance. Results of bioassays showed high resistance factors (RF > 41). The molecular tests showing the presence of the domain II mutation and absence of the domain III mutation in the voltage-gated sodium channel gene. Biochemical tests showed increased activity of esterases, multifunction oxidases and glutathione transferases in resistant samples. Genotyping the samples showed high levels of heterozygous genotypes (73.36% and 63.30%) as compared to homozygous susceptible and resistant genotypes (23.3% and 10%) respective at Samiondji and Betecoucou. A correlation between phenotype resistance and presence of the domain II mutation at the voltage gated sodium channel gene was observed suggesting that this could be associated with resistance. Target site mutation and metabolic detoxification are mechanisms of resistance to pyrethroids in R. microplus tick populations from Benin.

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

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. Conclusions: 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.

Sensitivity of Different Cattle Breeds to the Infestation of Cattle Ticks Amblyomma variegatum, Rhipicephalus microplus, and Hyalomma spp. on the Natural Pastures of Opkara Farm, Benin

A study was carried out on the Opkara (Benin) cattle farm on 64 cattle of four different breeds (16 individuals per breed) from June to December 2016. During this study, three tick species were found in different numbers, Amblyomma variegatum (732), Rhipicephalus microplus (8079), and Hyalomma spp. (208), with parasitic intensity of 11.90, 126.23, and 3.25, respectively. The interracial comparison of the tick infestation between the cattle showed a significant difference (P < 0.001). However, Girolando was more infested than all the cattle breeds. Infestation of A. variegatum, R. microplus, and Hyalomma spp. on the Girolando was, respectively, 19.43 ± 2.71, 171.25 ± 23.50, and 7.12 ± 0.63, but the Borgou were less infested. Borgou breed females were more infested by A. variegatum (4.41 ± 1.14) than females Girolando (4.20 ± 0.90). The Crossbred and Azawak females were less infested (P < 0.01). The mean of A. variegatum on Borgou, Azawak, Crossbred, and Girolando calves was 1.29 ± 0.35, 0.66 ± 0.26, 1.37 ± 0.37, and 2.25 ± 0.48 (P < 0.01), respectively. The results of this study can be exploited to include genetic and nongenetic approaches to tick control.

Molecular characterization of pyrethroids resistance mechanisms in field populations of Rhipicephalus microplus (Acari: Ixodidae) in district of Kpinnou and Opkara, Benin

ABSTRACT The tick Rhipicephalus microplus developed resistance against synthetic pyrethroid classes used for its control. The aim of this study was to characterize resistance of R. microplus for synthetic acaricides in order to establish an efficient control plan. The adult immersion test (AIT) was performed to test the susceptibility of R. microplus ticks to pyrethroids in two districts of Benin. Besides after DNA extraction from the tick larvae, a molecular identification test was done. Specific primers were used to determine the different mutations on the sodium channel gene in R. microplus population by PCR. AIT revealed a reproductive index of 0.02 ± 0.01 (p < 0.001) (Kpinnou) and 0.04 ± 0.02 (p < 0.03) (Opkara) with alphacypermethrin. Using deltamethrin, reproductive index was 0.24 ± 0.01 (p < 0.05) at Kpinnou and 0.10 ± 0.03 at Opkara, all at a concentration of 4 mg/ml. The resistance factors (RF) in the two districts were well above 41. The T2134A mutation was absent on the investigated farms. Regarding the C190A mutation, 86.67% and 56.67% of R. microplus larvae have resistant homozygotes in Kpinnou and Opkara, respectively. The introduction of new methods of tick control is essential to limit its population and control resistance.

In vitro evaluation of the acaricidal effect of vegetal oils extracted from the kernel of Thevetia peruviana and Annona muricata on the Rhipicephalus (Boophilus) microplus larvae

The objective of this work was to study the acaricide activity of oils extracted from kernels of T. peruviana and A. muricata with the hexane at different concentrations on Rhipicephalus (Boophilus) microplus larvae aged from 14 to 21 days. For this purpose, the Larva Immersion Test was performed. Twice dilutions of both oils were tested from a starting dilution of 40% to 2.5%. There were three repetitions for each concentration and for each oil. The control solution in which these larvae were treated consisted of Tween-20, diluted at 2% in distilled water. The experimental groups were stored in an incubator at 27 ± 1 °C and at 85-90% of relative humidity for 24 hours. The larvae mortality was greater than 55% in all tested groups and reached 100% at the 40% concentration for A. muricata , while the control group had a 0% mortality. The LC 50 and CL 90 obtained were respectively 4.0331% and 10.7594% for A. muricata and 7.0942% and 41.4247% respectively for T. peruviana . These results clearly indicate that these oils all have acaricidal effects on Rhipicephalus (Boophilus) microplus larvae. However, A. muricata oil is the most toxic. It can therefore be used as an effective alternative to control the Rhipicephalus (Boophilus) microplus tick and there is a high probability that it can be used for other ticks affecting cattle and even other ectoparasites in Benin and worldwide, thereby reducing the use of synthetic acaricides which are toxic to the environment and ineffective against this tick.

CHARACTERISTICS OF THE CARCASS AND NUTRITIONAL VALUES OF BREED GRASSCUTTER MEAT (THRYONOMYS SWINDERIANUS) FED WITH PELLETS IN BENIN.

F. F. Aizoun 1,2* , S. C. B. Pomalegni 1 , C. D. S. J Gbemavo 3 , A. K. I. Youssao 4 , S. Farougou 2 , G. A. Mensah 1 . 1. Laboratory of Zootechnical, Veterinary and Halieutic Research (LRZV), Centre of Agricultural Research/Agonkanmey (CRA) of the National Institute of Agricultural Research of Benin (INRAB), 01 BP 884 Master recipe, Cotonou, 01 Republic of Benin. 2. Department of Animal Production and health, Biotechnology Research Unit of Production and Animal Health, Polytechnic School of Abomey-Calavi, University of Abomey-Calavi (UAC), 01 BP 2009 Cotonou, Benin. 3. Laboratory of Biomathematics and Forest Estimates (LABEF), Faculty of Agricultural Sciences, University of Abomey-Calavi (UAC), 04 BP 1525, Cotonou, Benin. 4. University of Abomey-Calavi (UAC),Polytechnic School of Abomey-Calavi (EPAC), Department of Animal Production and health, Laboratory of Research in Applied Biology, 01 BP 2009 Cotonou, Benin. ...................................................................................................................... ManuscriptInfo Abstract ......................... ........................................................................ Manuscript History

INFLUENCE OF THREE PELLETS BASED GREEN FODDERS, PRODUCTS AND BY-PRODUCTS MAIZE ON THE GROWTH OF BRED GRASSCUTTER (THRYONOMYS SWINDERIANUS) IN BENIN.

F. F. Aizoun 1,2 *, S. C. B. Pomalegni 1 , C. D. S. J. Gbemavo 3 , S. Farougou 2 , A. K .I. Youssao 4 and G.A. Mensah 1 . 1. Laboratory of Zootechnical, Veterinary and Halieutic Research (LRZV), Centre of Agricultural Research/Agonkanmey (CRA) of the National Institute of Agricultural Research of Benin (INRAB), 01 BP 884 Master recipe, Cotonou, 01 Republic of Benin. 2. Department of Animal Production and health, Biotechnology Research Unit of Production and Animal Health, Polytechnic School of Abomey-Calavi, University of Abomey-Calavi (UAC), 01 BP 2009 Cotonou, Benin. 3. Laboratory of Biomathematics and Forest Estimates (LABEF), Faculty of Agricultural Sciences, University of Abomey-Calavi (UAC), 04 BP 1525, Cotonou, Benin. 4. University of Abomey-Calavi (UAC),Polytechnic School of Abomey-Calavi (EPAC), 2Department of Animal Production and health, Laboratory of Research in Applied Biology, 01 BP 2009 Cotonou, Benin. ...................................................................................................................... ManuscriptInfo Abstract ......................... ........................................................................ Manuscript History