Survey of External Parasites of Wild Birds in Kaduna State, Nigeria

Aims: As wild birds interact with poultry the likelihood of exchange of external parasites between wild birds and poultry highlights the need to understand wild bird parasites so as to reduce cross infection at the wild bird-poultry interface. There is paucity of data on external parasites of wild birds in Kaduna State, Nigeria. This study investigated the prevalence and diversity of external parasites among wild birds in Kaduna State. Place and Duration of Study: The study was carried out in Kaduna State, Nigeria between March, and June 2012. Methodology: Wild birds were captured and examined for external parasites by visual and microscopic examination. The data were analyzed using Quantitative Parasitology software. Results: Of the 233 wild birds representing 56 species and 25 families examined, the ectoparasite prevalence was 10.7% (25/233). The ectoparasites identified were Menacanthus spp (0.9%), Amblyomma variegatum (0.9%), Argas persicus (3.4%), Gonides gigas (2.1%) and Rhipicephalus spp (2.6%). Streptopelia senegalensis and Chalcomitra senegalensis were infested with Amblyomma varigatum while Numida meleagris and Ploceus cucullatus had Rhipicephalus spp. Conclusion: This is the first report to the best of our knowledge of hard tick infestation of free flying birds in Kaduna State. This study establishes baseline data for future study of wild bird host-parasite interaction in Nigeria. There is need for more studies on external parasites of wild birds to understand their impact on the survival of wild bird species in Nigeria.

Ecology of Ticks (Ixodidae) on Cattle within Main Campus of the University of Abuja, Nigeria

A survey was conducted using standard parasitological procedures to determine the ecology of ticks on the cattle within the main campus of the University of Abuja, Nigeria. The tick specie identified were Amblyomma variegatum, Amblyomma hebraeum, 0rnithodorus moubata complex, Hyalomma truncatum, Hyalomma rufipies, Rhipicephalus decoloratus, Phipicephalus appendiculatus, and Boophilus microplus. Of the 100 cattle examined. 47(47%) of the tick examined was found on the male cow and 53(53%) were found on the female cow. In addition, 23(23%) of the observed tick are found on the leg, 20(20%) are found in the anus, 20(20%) are found on the udder, 14(14%) are found on the back while 23(23%) of the ticks are found in the ear. 31(31%) of the observed ticks were found on the bunaj specie, 24(24%) of the ticks on the Gudali, 24(24%) of the observed ticks on the Rahaji specie and 21(21%) on the wadara specie. Amblyomma hebraeum, Ornithodorus moubata Complex and Rhipicephalus dicoloratus were found more dominantly on Bunaj breed (42.9%, 55.6% and 42.9% respectively), Amblyomma variegatum and Phipicephalus appendiculatus was observed to be more dominant on Rahaji breed (infesting 33.3% and 66.7% respectively), Boophylus microplus and Hyalomma rufipe were found dominant on wadara (30% and 50% respectively). There is need to help establish baseline information on ticks ecology and occurrence in the study area which would consequently lead to increased public awareness especially to the herdsmen and in avoiding tick borne diseases, also to help in vector control formulation and to prevent the herdsmen of suffering from low productivity due to the presence of ticks, thereby leading to various weaknesses, diseases and sometimes death of the cattle. Owing to this, this study did not only identify the tick species infesting cattle but also examined the host-parasite ecology of ticks on cattle within the main campus of the University of Abuja, Nigeria.

Rickettsia africae: identifying gaps in the current knowledge on vector-pathogen-host interactions

Rickettsia africae is a bacterium of zoonotic importance, which causes African tick bite fever (ATBF) in humans. This pathogen is transmitted by ticks of the genus Amblyomma, with Amblyomma hebraeum and Amblyomma variegatum being the major vectors. Tick species other than the above-mentioned have also been reported to carry R. africae DNA. There is scarcity of information on the epidemiology of this pathogen, yet several cases have been recorded in foreign travellers who visited endemic areas, especially southern Africa. The disease has rarely been described in people from endemic regions. The aim of this study was to discuss the information that is currently available on the epidemiology of R. africae, highlighting the gaps in this field. Furthermore, ATBF cases, clinical signs and the locations where the cases occurred are also listed in this review.

Efficacy of two commercial synthetic pyrethroids (cypermethrin and deltamethrin) on Amblyomma variegatum and Rhipicephalus microplus strains of the south-western region of Burkina Faso

Since 2011, period of the livestock invasion by the cattle tick Rhipicephalus microplus in Burkina Faso (BF), tick-control problems were exacerbated. Based on farmer’s reports, most commonly used commercial acaricides were found to be ineffective in Western South part of the country. To investigate the occurrence and extent of such acaricidal ineffectiveness, we performed the standardized larval packet test (LPT) with commercial deltamethrin (vectocid) and cypermethrin (cypertop), on two cattle tick species, the native Amblyomma variegatum and the invasive R. microplus. The resistance ratios (RR) were computed with susceptible Hounde strain of Rhipicephalus geigyi as reference. The R. microplus population showed resistance to the two acaricides tested with the highest lethal concentration (LC) values, and different resistance ratios higher than 4 (deltamethrin: RR50 = 28.18 and RR90 = 32.41; cypermethrin: RR50 = 8.79 and RR90 = 23.15). In the contrary, A. variegatum population was found to be highly susceptible to acaricides tested with low lethal concentrations and resistance ratio values (deltamethrin: RR50 = 0.5 and RR90 = 0.48; cypermethrin: RR50 = 0.68 and RR90 = 0.79). These data demonstrate high synthetic pyrethroid resistance in R. microplus strain, leading to conclude that the acaricide ineffectiveness in tick populations control remains a concern in BF.

The influence of disease-inducing agents other than Dermatophilus congolensis on the severity of bovine dermatophilosis

This study was designed to assess the influence of disease-inducing agents other than Dermatophilus congolensis on the incidence of bovine dermatophilosis from cattle farms in Federal University of Agriculture, Abeokuta and Olabisi Onabanjo University, Ogun State and also from Akinyele cattle market in Oyo State. Skin scrapings collected from cattle with typical lesions of dermatophilosis were examined for the presence of bacteria, fungi and ectoparasites. Out of the 57 animals examined with typical skin lesions of dermatophilosis, Dermatophilus congolensis organism was cultured from 23 cases. Other bacterial organisms identified included Staphylococcus aureus (28 cases), Staphylococcus albus (35 cases), Bacillus mycoides (14 cases), Bacillus cereus (1 case), haemolytic Streptococcus (5 cases) Pseudomonas aeruginosa (13 cases), Escherichia coli (16 cases), Proteus spp (4 cases) and Norcardia spp (5 cases). Ticks (mostly Amblyomma variegatum) were seen in all the 57 animals while Demodex bovis, Sarcoptes scabiei var bovis and lice were seen in 15, 4 and 8 cases respectively. It was inferred that secondary bacterial invasions are associated with the pathogenesis and severity of the infection and the presence of ticks and mange mites may serve as the portal of entry for dermatophilosis infection. The control of dermatophilosis should take into account of arthropod vectors and secondary bacterial complications.

SOME PARASITES OF FERAL WESTERN KOB (Kobus Kob kob) OF LAKE KAINJI NATIONAL PARK, NIGERIA

The parasites of kob based on physical, faecal and blood examination has revealed that kob harbor ticks which include Rhipicephalus evertsi, Rhipicephalus nymph, Amblyomma variegatum; lice, Damalinia sp; and fed upon by by biting fly Culicoides. sp. Helminth ova found were Strongyl sp. and Fasciola. sp.; protozoan. Babesia sp. in blood and Eimeria sp. in faeces. The significance of tick as vector of parasites of domestic animals and the potential risk of kob as reservoir of the parasites these vectors transmit are discussed. The prevalence of Strongyl sp. and Fasciola sp. ova as reflection of worm burden and potential pasture contamination are highlighted

Efficacy of tobacco extract and Flumethrin Pour-on against cattle tick, Amblyomma variegatum

The comparative efficacies of topical tobacco extract and flumethrin pour -on against the cattle tick Amblyomma variegatum was evaluated. Thirty Ndama cattle were divided into three treatment groups often animals per group viz: Flumethrin treatment group ; Tobacco treatment group 2 and the untreated control group 3, in a completely randomized design. Ticks were counted visually and by palpation of affected areas at 0.7, 21, 28 and 35-day period. Backline application of flumethrin was from the pole to the base of the tail according to manufacturer's instruction while application of tobacco was through the aid of cotton wool soaked in liquid tobacco extract. The flumethrin pour-on produced a significant reduction in tick count by the 21" day reaching as high as 100 %( 43.33 and 0) while the tobacco extract produced comparable result at a longer time of 35 days (46.22 and 0). The tobacco extract however maintained the protection against Amblyomma variegatum in the face of continuous challenge by injective tick larvae up until the 64" day post challenge. Significant re-infestation of ticks could be seen however in the flumethrin count 40 day post challenge. This confirmed the efficacy of tobacco in protecting cattle against tick, Amblyomma variegatum.

Ngari virus (Orthobunyavirus, Peribunyaviridae) in ixodid ticks collected from cattle in Guinea

Ngari virus is a mosquito-borne virus belonging to the genus Orthobunyavirus (Peribunyaviridae family). This virus is pathogenic to humans and causes severe illness. Ngari virus is present in several African countries, including Madagascar. Here, we report the detection of Ngari virus in ixodid ticks collected from cows in Guinea.A tick survey was conducted in March-November of 2018 in six regions of Guinea. The sample comprised 710 pools, with a total of 2067 ticks belonging to five species collected from 197 cows. At the initial stage, we screened a subsample of tick pools of vector-borne viruses with a multiplex genus-specific primer panel. In the second stage of the study, we narrowed the search and screened all the samples by qPCR for the detection of Ngari virus. All positive samples were sequenced with primers flanking Ngari virus-specific fragments on the S and M segments.We found Ngari virus in 12 pools that were formed from engorged ticks collected from livestock in three villages of the Kindia and Kankan regions. Sequencing of the S and M segments confirmed that the detected viruses belong to Ngari virus, and the viruses were most similar to the strain Adrar, which was isolated in Mauritania. We detected viral RNA in ticks of the following species: Amblyomma variegatum, Rhipicephalus geigyi, and Rh. (Boophilus) spp. There is no evidence that ixodid ticks are competent vectors of the Ngari virus. Most likely, the ticks obtained the virus through blood from an infected host.

Study on ruminant tick infestation, phytochemical analysis and in vitro acaricidal effect of Calpurnia aurea and Otostegia integrifolia extracts on Amblyomma variegatum

Ticks limit the productivity of livestock through decreased production, reproduction, increased mortality, downgrading and rejection of hides and skin. A cross-sectional study was conducted to estimate the prevalence of tick infestation in ruminant while experimental study was used to evaluate the in-vitro acaricidal efficacy of methanolic extracts: Calpurnia aurea and Otostegia integrifolia and the phytochemicals present in those extracts at different concentrations (200, 100, 50, 25, 12.5 and 6.25 mg/ml) against Amblyomma variegatum. Adult immersion was used for the in-vitro acaricidal efficacy test and plant extracts were subjected to qualitative phytochemical screening for the presence or absence of secondary metabolites using standard procedures. Out of the 160 goats, 152 sheep and 121 cattle, 23 (14.4%), 44 (28.9%) and 28 (23.1%) were found to be positive for tick infestation, respectively. The incidence of tick infestation was significantly different (p<0.01) among ruminants. Five tick spp. were identified: A. variegatum, A. gemma, R. decoloratus, R. evertsi evertsi and R. pulchellus. Extract of C. aurea and O. integrifolia was found to contain alkaloids, saponins, phlobatannin, steroids, phenolic, flavonoids, glycosides and tannins. However, both plants were found negative for triterpens. Extracts of C. aurea and O. integrifolia at 200 and 100 mg/ml concentrations showed a significantly higher (p<0.05) acaricidal activities compared to other treatments at 24 hrs post exposure. Mortality of ticks was increased with the increased dosage (concentration) and exposure time after treatment. Extracts of C. aurea showed a significantly higher (p<0.05) tick mortality (52%) compared to those of O. integrifolia (27%). This is a promising finding to have alternative means of treatment and to substitute the use of synthetic drugs which have a wide spread drug resistance especially in developing countries like Ethiopia. Key words: Calpurnia aurea; in-vitro test; Otostegia integrifolia; Phytochemical screening; Tick infestation