Inventaire des espèces de tiques (Arthropoda; Ixodinae) parasites des bovins et recherche de pathogène chez les tiques du genre Hyalomma au niveau de deux étages bioclimatiques.

Abstract

Cattle are confronted to vector-borne diseases which reduce their growth, meat quality and milk production. Hard ticks are vectors of pathogens that cause bacterial, viral and parasitic diseases. In Algeria, parasitosis such as piroplasmosis whose vectors are ticks or we can witness serious damage and sometimes mortality even with treatment, especially during bovine theileriosis. We chose to identify the problem of the infestation of cattle by ticks thus, our work consisted in carrying out an inventory of the ticks present in three regions with different bioclimatic status (Jijel; humid, Guelma; sub-humid and Mila; semi- -arid), 2816 ticks; 947 in Mila, 1464 in Jijel and 405 in Guelma were collected from 402 cattle, 196 goats and 182 sheep. We were able to identify ten species of hard ticks, Rhipicephalus (Boophilus) annulatus, Rhipicephalus bursa, Rhipicephalus camicasi, Rhipicephalus sanguineus, Hyalomma marginatum, Hyalomma excavatum, Hyalomma scupense, Hyalomma lusitanicum, Hyalomma impeltatum, Hyalomma anatolicum. We have also demonstrated that ticks are not equidistributed according to species by studying ecological indices thus Rhipicephalus (Boophilus) annulatus was mainly found in Jijel and Guelma, Rhipicephalus bursa and Rhipicephalus sanguineus are very high in Mila, Hyalomma excavatum only present in Guelma and Mila. We also note the presence of Rhipicephalus camicasi for the first time in Algeria. Regarding the sex of ticks, the percentage of females of the genus Rhipicephalus is higher than that of males, on the other hand for Hyalomma the males are more present. The study of biotic factors namely sex, age and breed of cattle showed a significant difference in the prevalence and intensity of tick infestations, we note that the intensity of infestation by category d Cattle age was found to be statistically significant in cattle with an average age of 3.5 and 5.5 years. We also noted in our study the grouping of different species of ticks thus, Rhipicephalus sanguineus formed a group with Rhipicephalus bursa in Mila and that in Jijel Hyalomma anatolicum associated with Rhipicephalus (Boophilus) annulatus. Species association is an effective strategy for hard ticks that can lead to an exchange of pathogens over time. This grouping of species was also related to the density of ticks, so the low density species, Jijel Rhipicephalus sanguineus, Mila Hyalomma excavatum and Hyalomma impeltatum tended to group together with the species that had the highest densities. Through this work we contribute to the systematics of ticks and we bring a new approach to the study of biotic factors.