Background: The majority of the African population lives in rural areas where they heavily depend... more Background: The majority of the African population lives in rural areas where they heavily depend on crop and livestock production for their livelihoods. Given their socio-economic importance, we initiated a standardized multi-country (Benin, Burkina Faso, Ghana, Nigeria, Ethiopia Tanzania and Uganda) surveillance study to assess the current status of important tick-borne haemoparasites (TBHPs) of cattle across these seven sub-Saharan African territories. Methods: We assessed vector-borne pathogen prevalences (Anaplasma marginale, Anaplasma centrale, Babesia bigemina, Babesia bovis, Ehrlichia ruminantium, and Theileria parva) in the blood of cattle, via molecular screenings in approximately 480 individuals per district in two districts per country and seven countries each. In addition, we screened for intrinsic (sex, weight, body condition) and extrinsic (husbandry, tick exposure) risk factors as predictors of infections with TBHPs. Results: There was a large macro-geographic variat...
Diapause in adults of the African brown ear tick Rhipicephalus appendiculatus is dependent on lat... more Diapause in adults of the African brown ear tick Rhipicephalus appendiculatus is dependent on latitude and stock origin. Lower latitude populations, that is, those nearer the equator, show no diapause response to long or short day exposure. Diapause response to short day lengths is found in higher latitude populations, further south, and increases with increasing latitude. Nearly all individuals in
Newly-moulted adults of three Rhipicephalus appendiculatus stocks, originating from Kenya, Zambia... more Newly-moulted adults of three Rhipicephalus appendiculatus stocks, originating from Kenya, Zambia and Zimbabwe, were kept in different photoperiods (12h : 12h, 13h : 11h and 14h : 10h light : dark). The stock originating from Kenya showed almost no behavioural diapause in any of these day lengths, whereas virtually all individuals of the Zimbabwean stock entered a behavioural diapause irrespective
Infectious bovine rhinotracheitis is caused by the bovine herpesvirus type 1. It is an enzootic d... more Infectious bovine rhinotracheitis is caused by the bovine herpesvirus type 1. It is an enzootic disease on the B List of the Office International des Epizooties (O.I.E.). Programs to eradicate bovine herpesvirus type I have been implemented in several European countries to facilitate the free trade of cattle, semen and embryos within the European Community. Therefore, Belgium has an incentive
... and being able to predict) nymphal activity patterns is of epidemiological importance and ess... more ... and being able to predict) nymphal activity patterns is of epidemiological importance and essential for modelling purposes (Floyd, 1987; Randolph & ... Pegram and Banda (1990) also observed that R. appendiculatus nymphs were questing early in the morning and afternoon and ...
A new method has been developed to investigate behavioural diapause in adult Rhipicephalus append... more A new method has been developed to investigate behavioural diapause in adult Rhipicephalus appendiculatus ticks. It is based on a system of gauze columns in which the activity of the ticks can be monitored in the laboratory. An experiment was conducted, involving different photoperiodic conditions during the nymph-to-adult moulting and pre-questing periods, with the aim of comparing the results obtained by the in vitro method with those of the standard in vivo method. Comparable results were obtained with both methods.
Donkeys (Equus asinus) are rustic animals, but in Africa's poorest regions, they can present ... more Donkeys (Equus asinus) are rustic animals, but in Africa's poorest regions, they can present multiple health problems, including tick infestation. The study's objective was to determine the species composition of ticks that infest donkeys in Maputo Province (Mozambique). Ticks were collected in five conveniently selected southern districts of Maputo Province (Moamba, Matutuíne, Marracuene, Boane, and Matola) and were identified to species level using a stereoscopic microscope with the aid of dichotomous identification keys. In total, 500 ticks were collected from all 88 selected donkeys. Three genera of ticks were identified, namely Rhipicephalus (97.2%; 486/500), Amblyomma (2.2%; 11/500), and Hyalomma (0.6%; 3/500). Seven species were identified, of which Rhipicephalus evertsi evertsi with 50.4% (252/500) was the most prevalent, followed by Rhipicephalus appendiculatus (27.4%; 137/500), Rhipicephalus turanicus (11.6; 10/500), Rhipicephalus (boophilus) microplus (6.8; 20/500), Amblyomma hebraeum (2.2%; 11/500), Rhipicephalus sanguineus (1%; 5/500) and Hyalomma truncatum (0.6%; 3/500). Rhipicephalus evertsi evertsi occurred in all locations, whereas Hyalomma truncatum occurred only in the Boane district. Males were the most prevalent (67.2%; 336/500). The study revealed that donkeys in Maputo Province were infested with seven tick species of which R. evertsi evertsi was the main species.
Background Ticks infesting animals constitute one of the most important factors limiting profitab... more Background Ticks infesting animals constitute one of the most important factors limiting profitable livestock production in sub-Saharan Africa and the region is beleaguered by a paucity of data on diseases implicated in high morbidity and mortality in most of its livestock production systems. Methods In a tick endemic Guinea savannah ecosystem, ticks infesting calves and yearlings during their first eighteen months of life were collected weekly and morphologically identified. PCR, Restriction Fragment Length Polymorphism (RFLP) and sequencing were applied on DNA of tick-borne pathogens in animal blood buffy coat to amplify and characterize the 16S rRNA genes of Anaplasma, Ehrlichia and 18S rRNA gene for Babesia spp. Results Of 31 364 adult ticks, nymphs and larvae collected from the 20 experimental animals, 6525 (20.1%), 7399 (23.6%), 990 (3.2%), 16450 (52.4%) were Amblyomma variegatum, Rhipicephalus spp., other genera, and tick larvae respectively. Tick infestation rates during the...
Background: The majority of the African population lives in rural areas where they heavily depend... more Background: The majority of the African population lives in rural areas where they heavily depend on crop and livestock production for their livelihoods. Given their socio-economic importance, we initiated a standardized multi-country (Benin, Burkina Faso, Ghana, Nigeria, Ethiopia Tanzania and Uganda) surveillance study to assess the current status of important tick-borne haemoparasites (TBHPs) of cattle across these seven sub-Saharan African territories. Methods: We assessed vector-borne pathogen prevalences (Anaplasma marginale, Anaplasma centrale, Babesia bigemina, Babesia bovis, Ehrlichia ruminantium, and Theileria parva) in the blood of cattle, via molecular screenings in approximately 480 individuals per district in two districts per country and seven countries each. In addition, we screened for intrinsic (sex, weight, body condition) and extrinsic (husbandry, tick exposure) risk factors as predictors of infections with TBHPs. Results: There was a large macro-geographic variat...
Diapause in adults of the African brown ear tick Rhipicephalus appendiculatus is dependent on lat... more Diapause in adults of the African brown ear tick Rhipicephalus appendiculatus is dependent on latitude and stock origin. Lower latitude populations, that is, those nearer the equator, show no diapause response to long or short day exposure. Diapause response to short day lengths is found in higher latitude populations, further south, and increases with increasing latitude. Nearly all individuals in
Newly-moulted adults of three Rhipicephalus appendiculatus stocks, originating from Kenya, Zambia... more Newly-moulted adults of three Rhipicephalus appendiculatus stocks, originating from Kenya, Zambia and Zimbabwe, were kept in different photoperiods (12h : 12h, 13h : 11h and 14h : 10h light : dark). The stock originating from Kenya showed almost no behavioural diapause in any of these day lengths, whereas virtually all individuals of the Zimbabwean stock entered a behavioural diapause irrespective
Infectious bovine rhinotracheitis is caused by the bovine herpesvirus type 1. It is an enzootic d... more Infectious bovine rhinotracheitis is caused by the bovine herpesvirus type 1. It is an enzootic disease on the B List of the Office International des Epizooties (O.I.E.). Programs to eradicate bovine herpesvirus type I have been implemented in several European countries to facilitate the free trade of cattle, semen and embryos within the European Community. Therefore, Belgium has an incentive
... and being able to predict) nymphal activity patterns is of epidemiological importance and ess... more ... and being able to predict) nymphal activity patterns is of epidemiological importance and essential for modelling purposes (Floyd, 1987; Randolph & ... Pegram and Banda (1990) also observed that R. appendiculatus nymphs were questing early in the morning and afternoon and ...
A new method has been developed to investigate behavioural diapause in adult Rhipicephalus append... more A new method has been developed to investigate behavioural diapause in adult Rhipicephalus appendiculatus ticks. It is based on a system of gauze columns in which the activity of the ticks can be monitored in the laboratory. An experiment was conducted, involving different photoperiodic conditions during the nymph-to-adult moulting and pre-questing periods, with the aim of comparing the results obtained by the in vitro method with those of the standard in vivo method. Comparable results were obtained with both methods.
Donkeys (Equus asinus) are rustic animals, but in Africa's poorest regions, they can present ... more Donkeys (Equus asinus) are rustic animals, but in Africa's poorest regions, they can present multiple health problems, including tick infestation. The study's objective was to determine the species composition of ticks that infest donkeys in Maputo Province (Mozambique). Ticks were collected in five conveniently selected southern districts of Maputo Province (Moamba, Matutuíne, Marracuene, Boane, and Matola) and were identified to species level using a stereoscopic microscope with the aid of dichotomous identification keys. In total, 500 ticks were collected from all 88 selected donkeys. Three genera of ticks were identified, namely Rhipicephalus (97.2%; 486/500), Amblyomma (2.2%; 11/500), and Hyalomma (0.6%; 3/500). Seven species were identified, of which Rhipicephalus evertsi evertsi with 50.4% (252/500) was the most prevalent, followed by Rhipicephalus appendiculatus (27.4%; 137/500), Rhipicephalus turanicus (11.6; 10/500), Rhipicephalus (boophilus) microplus (6.8; 20/500), Amblyomma hebraeum (2.2%; 11/500), Rhipicephalus sanguineus (1%; 5/500) and Hyalomma truncatum (0.6%; 3/500). Rhipicephalus evertsi evertsi occurred in all locations, whereas Hyalomma truncatum occurred only in the Boane district. Males were the most prevalent (67.2%; 336/500). The study revealed that donkeys in Maputo Province were infested with seven tick species of which R. evertsi evertsi was the main species.
Background Ticks infesting animals constitute one of the most important factors limiting profitab... more Background Ticks infesting animals constitute one of the most important factors limiting profitable livestock production in sub-Saharan Africa and the region is beleaguered by a paucity of data on diseases implicated in high morbidity and mortality in most of its livestock production systems. Methods In a tick endemic Guinea savannah ecosystem, ticks infesting calves and yearlings during their first eighteen months of life were collected weekly and morphologically identified. PCR, Restriction Fragment Length Polymorphism (RFLP) and sequencing were applied on DNA of tick-borne pathogens in animal blood buffy coat to amplify and characterize the 16S rRNA genes of Anaplasma, Ehrlichia and 18S rRNA gene for Babesia spp. Results Of 31 364 adult ticks, nymphs and larvae collected from the 20 experimental animals, 6525 (20.1%), 7399 (23.6%), 990 (3.2%), 16450 (52.4%) were Amblyomma variegatum, Rhipicephalus spp., other genera, and tick larvae respectively. Tick infestation rates during the...
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