Abstract:
Tick infestation has direct impact on animal health and production in many parts of the world, including sub-Saharan Africa. Tick infestation causes important economic losses, particularly in tropical and subtropical countries.
A cross-sectional study was conducted from December 2017 to April 2018 to determine the prevalence of tick infestation in cattle, sheep and goats in Khartoum North, investigate the potential risk factors associated with tick infestation in these livestock species. A total of 277 animals of different species (182 cattle, 60 sheep and 35 goats) were selected randomly and examined for tick infestation at 44 farms in Bahri and Sharg Alneel in Khartoum North (Algaili, Wadramli, Wawissi, Samrab, Shigla, Silait, Kafouri, Ailafoon and Kuku).Predesigned questionnaire was used for each examined animal to identify possible risk factors associated with tick prevalence prior to tick collectionand collected ticks werefurther morphologically identified using taxonomic keys.
The highest prevalence of tick infestation was recorded in Bahri area 88.8% and 52.6% was in Sharg Alneel. About 68.9% (191/277) of total observed animals were found infested by ticks with the highest rate in cattle (74.2%) followed by sheep (66.7%) and goats (45.7%). Regarding the associated risk factors, tick infestation was found significant (P < 0.004) different among the three species of animals.Old animals (<5 years old of cattle) and (< 3years old of sheep and goats) had the highest prevalence of 87.8% compared with adults (2–5 years old of cattle) and (<6 months–3 years old of sheep and goats) 66.1% and young (> 2 years old of cattle) and (1-6 months in sheep and goat) 56.1%. Females had slightly higher prevalence of 71.1% compared with the males 59.2%. Crossbred and foreign breed had the highest prevalence of tick infestations of 72.4% compared with local breed 62.0%.Medium herd size had the highest prevalence of tick infestation of 80.7% compared with the small herd size 67.6 % and the lowest reported in the large herd size of 20.8%. Animal kept in semi closed registered the highest prevalence of tick infestation of 95.7% compared with those kept in closed one 59.9%. The prevalence of tick infestation in farms where control of ticks was practiced was greatly less (55.1%) than farms without tick control (90%).There was significant association between tick infestation prevalence and different methods of tick control.Weekly removing of manure decreased the tick infestation prevalence (48.3%) much better than the monthly removing of manure (94.5%).The highest prevalence of tick was reported in summer (83.1%) compared with autumn (60.6%). Distribution of the tick species in different livestock revealed that, cattle were more infested by Hyalomma. anatolicum, sheep were more infested byRhipicephalus sanguineous and goats were more infested by Rhipicephalus e. evertsi.
From the total count of 2367 ticks (male 1591, female776) collected, three genera and five species were identified of which the dominant tick species was Hyalomma anatolicum, Rhipicephalus e. evertsi, Rhipicephalus Sangiuanus group, Hyalomma rufipes and less frequently Amblyomma lepidum.Udder was the most tick infested site in cattle(54.5%), ears were the most tick infested site in sheep (70.6%) and tail was the most tick infested site in goats (77.5%).
High prevalence of tick infestation reported among examined cattle, sheep and goats population was in Khartoum North. Animal species, age, herd size, housing type, tick control, control method, removing of manure and season were considered risk factors for tick infestation prevalence. Hyalomma anatolicum was the most common tick species infesting ruminants in the study area.