Ixodid ticks of traditionally managed cattle in central Nigeria: where Rhipicephalus (Boophilus) microplus does not dare (yet?)

BACKGROUND: Ticks and tick-borne diseases (TBDs) undermine cattle fitness and productivity in the whole of sub-Saharan Africa, including Nigeria. The aim of this study was to document the composition of tick species, assessing the burden of infestation, in traditionally managed cattle in an area of central Nigeria where acaricides have not been used historically. METHODS: The study was carried out in September 2010 in 9 villages belonging to three neighbouring local government areas in Plateau State, Nigeria. In each village all visible adult ticks were collected from at least 15 cattle (mean number = 25). Collected ticks were preserved in 70% ethanol to be counted and morphologically identified to the species level. RESULTS: A total of 5011 ixodid ticks (1935 males and 3076 females) were collected from 228 cattle, comprising 14 calves, 33 juveniles, and 181 adults. Three tick genera (i.e., Amblyomma, Hyalomma, and Rhipicephalus, including the Boophilus sub-genus) and 11 species were identified. The most prevalent species was Rhipicephalus (Boophilus) decoloratus (41.4%), followed by Rhipicephalus (Boophilus) annulatus (15.4%), Rhipicephalus guilhoni (12.0%), Rhipicephalus (Boophilus) geigyi (7.6%), Hyalomma truncatum (7.4%), Amblyomma variegatum (6.3%), Rhipicephalus simus Group (4.0%), Rhipicephalus turanicus (1.2%), Rhipicephalus sanguineus (0.3%), Hyalomma rufipes (0.2%), and Rhipicephalus lunulatus (n = 1). Mean tick loads recorded were relatively high (22 ± 1.4), in spite of the practice of hand removal of ticks traditionally undertaken by the Fulani pastoralists in the area. Calves bore a significantly lower tick burden than adults (p = 0.004). Rhipicephalus (Boophilus) microplus was not found in the area, suggesting that the eastbound expansion of this tick species in West Africa, has not yet reached central Nigeria. CONCLUSIONS: This study ascertained the presence of a broad variety of cattle tick species, most of which are of veterinary importance. The presence of each tick species is correlated with the potential occurrence of tick-borne pathogens and suggestions for tick control in the area are considered. Results should assist the diagnosis of related TBDs in cattle as well as the strategic planning of cost-effective tick control

Tick-borne pathogens of zoonotic and veterinary importance in Nigerian cattle

Additional file 1: Multiple infections by tick-borne pathogens according to age classes and overall number of animals. (PDF 19 kb)BACKGROUND : Ticks and tick-borne diseases undermine cattle fitness and productivity in the whole of sub-Saharan Africa, including Nigeria. In this West African country, cattle are challenged by numerous tick species, especially during the wet season. Consequently, several TBDs are known to be endemic in Nigerian cattle, including anaplasmosis, babesiosis, cowdriosis and theilerioris (by Theileria mutans and Theileria velifera). To date, all investigations on cattle TBDs in Nigeria have been based on cytological examinations and/or on serological methods. This study aimed to ascertain the occurrence of tick-borne pathogens of veterinary and zoonotic importance in cattle in Nigeria using molecular approaches. METHODS : In October 2008, 704 whole blood samples were collected from indigenous cattle in the Plateau State, Nigeria. Analysis for tick-borne pathogens was conducted by means of PCR-based reverse line blotting (RLB) and sequencing targeting a panel of five genera of microorganisms (i.e. Babesia, Theileria, Anaplasma, Ehrlichia and Rickettsia spp.). RESULTS : In total, 561/704 (82.6 %) animals were found infected, with 465 (69.6 %) of them being infected by two or more microorganisms, with up to 77 possible combinations of pathogens detected. Theileria mutans was the most prevalent microorganism (66.3 %), followed by Theileria velifera (52.4 %), Theileria taurotragi (39.5 %), Anaplasma marginale (39.1 %), Anaplasma sp. (Omatjenne) (34.7 %), Babesia bigemina (7.9 %), Anaplasma centrale (6.3 %), Anaplasma platys (3.9 %), Rickettsia massiliae (3.5 %), Babesia bovis (2.0 %) and Ehrlichia ruminantium (1.1 %). Calves were found significantly less infected than juvenile and adult cattle. CONCLUSIONS : This study provides updated, molecular-based information on cattle TBDs in Nigeria. The molecular approach employed allowed the diagnosis of numerous positive cases including carrier statuses, multiple infections and novel pathogen detections within the indigenous cattle population. Moreover, the RLB method here described enabled the detection of veterinary agents not only pertaining to bovine health, including also those of zoonotic importance. The high prevalence recorded for T. mutans, T. velifera, A. marginale, T. taurotragi and Anaplasma sp. (Omatjenne), suggests they may be endemically established in Nigeria, whereas the lower prevalence recorded for other microorganisms (i.e. A. centrale and B. bovis) highlights a less stable epidemiological scenario, requiring further investigations.The UK’s Biotechnology and Biological Sciences Research Council (BBSRC) under the ‘Combating Infectious Diseases in Livestock for International Development’ (CIDLID) scheme, and the European Union’s Seventh Framework Program (FP7/2007–2013) under grant agreement n° 221948, Integrated Control of Neglected Zoonoses (ICONZ).http://www.parasitesandvectors.comam2016Veterinary Tropical Disease

Canine and ovine tick-borne pathogens in camels, Nigeria

AbstractIn April 2008, whole blood samples were collected from 36 dromedary camels in Sokoto, North-western Nigeria. Following PCR and reverse line blotting, twenty-two samples (61%) resulted positive for Ehrlichia/Anaplasma spp. and three (8%) for Theileria/Babesia spp., with three (8%) cases of co-infections being found. Both sequence and BLAST analyses identified Ehrlichia/Anaplasma spp. and Theileria/Babesia spp. positive cases as Anaplasma platys and Theileria ovis, respectively.This is the first report of the detection of A. platys and T. ovis in camels from sub-Saharan Africa. The epidemiological relevance of this finding is enhanced by the close living of these animals with both dogs and small ruminants. The high prevalence detected for A. platys suggests a possible role of camels as carriers of this infection

The Relationship between Wind Pressure and Pressure Coefficients for the Definition of Wind Loads on Buildings

Wind induced pressures on buildings are the product of a velocity pressure and a pressure coefficient. The way in which these two quantities are calculated has changed over the years, and Design Codes have been modified accordingly. This paper tracks the evolution of the approach to wind loading of buildings from the practice in the 1950s, mainly referring to the Swiss Code SIA, to the most recent advances including probabilistic methods, internet databases, and advanced modelling of meteorological phenomena

Load-Carrying Capacity of Compressed Wall-Like RC Columns Strengthened with FRP

The analytical prediction of the effectiveness of fiber-reinforced polymer (FRP) in the confinement of a rectangular reinforced concrete (RC) column with a high aspect ratio (wall-like) still has an uncertain solution. In this paper, a numerical investigation of the axial response of RC wall-like columns strengthened with FRP systems was developed. Analytical solutions proposed in the literature for the assessment of the axial load capacity were presented and compared with each other and with the available experimental results. Moreover, non-linear finite element analysis was carried out, and the results were discussed, providing a simple model for the assessment of the axial compressive strength of wall-like RC columns strengthened with FRP

The Relationship between Wind Pressure and Pressure Coefficients for the Definition of Wind Loads on Buildings

Wind induced pressures on buildings are the product of a velocity pressure and a pressure coefficient. The way in which these two quantities are calculated has changed over the years, and Design Codes have been modified accordingly. This paper tracks the evolution of the approach to wind loading of buildings from the practice in the 1950s, mainly referring to the Swiss Code SIA, to the most recent advances including probabilistic methods, internet databases, and advanced modelling of meteorological phenomena

Uncertainty in dynamic properties of flexible buildings to wind load

Setting appropriate values of the modal parameters of tall buildings under wind actions is a challenge. Despite both frequency and damping ratio are affected by uncertainty, the latter is recognized to be the main source of randomness in the assessment of the building response. Different analytical formulations have been proposed through the years, relating the damping ratio to the amplitude of oscillation, to the building height, and to frequency. However, these appear to disagree with each other, leading to ifferent estimates of damping. The main aim of the paper is the assessment of stochastic models for the dynamic properties of flexible buildings. To achieve it, available online frequency and damping databases are used. First, the accuracy of some available analytical models is assessed. Then, the datasets are analysed, and probabilistic models are proposed describing the uncertainty in frequency and damping ratio