Odeniran Paul Olalekan, Macleod Ewan Thomas, Ademola Isaiah Oluwafemi, Ohiolei John Asekhaen, Majekodunmi Ayodele Oluwakemi, Welburn Susan Christina
Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Nigeria.
Infection Medicine, Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9JZ, UK.
Acta Parasitol. 2021 Mar;66(1):116-128. doi: 10.1007/s11686-020-00260-9. Epub 2020 Aug 11.
Glossina spp. (Glossinidae), Tabanus spp. (Tabanidae), Ancala spp. (Tabanidae), Atylotus spp. (Tabanidae) and Stomoxys spp. (Muscidae) are important transmitting vectors of African animal trypanosomosis in sub-Saharan Africa. There is paucity of information on the distribution and identification of these flies in cattle settlements in southwest Nigeria.
The distribution patterns, genetic variations and diversities of dipteran flies in southwest Nigeria were described and identified using morphological and molecular analysis of the 28S rDNA gene.
Of the 13,895 flies examined morphologically between April 2016 and March 2017, tabanids were identified [Tabanus (0.34%), Ancala (0.03%), Atylotus (0.01%), Haematopota (0.014%) and Chrysops (0.11%)]. Two stomoxyine species were identified; Stomoxys niger niger Macquart (45.30%) and Stomoxys calcitrans Linnaeus (17.29%) and two Glossina spp. namely; Glossina p. gambiense Vanderplank, 1911 (0.46%) and Glossina tachinoides Westwood (0.51%) were identified. The identities were further confirmed in a BLAST search using their nucleotide sequences. The median-joining network of the 28S rDNA gene sequences indicated that fly species examined were genetically distinct. The apparent density of all the trapped flies was highest at a mean temperature of 26-28 ℃, humidity > 80% and rainfall of 150-220 mm/month. The distribution of flies was observed to increase as vegetation increased in density and decreased in areas with relatively high human population density (> 100/km).
The population indices of the 28S rDNA gene of the flies suggest that analysis of nuclear DNA fragments may provide more information on the molecular ecology of these flies. Characterising fly species and assessing their impact are essential in distribution and monitoring AAT spread.
舌蝇属（舌蝇科）、虻属（虻科）、鞍斑虻属（虻科）、麻虻属（虻科）和厩螫蝇属（蝇科）是撒哈拉以南非洲地区非洲动物锥虫病的重要传播媒介。关于尼日利亚西南部牛群聚居地这些苍蝇的分布和鉴定信息匮乏。
利用28S rDNA基因的形态学和分子分析，描述并鉴定了尼日利亚西南部双翅目苍蝇的分布模式、遗传变异和多样性。
在2016年4月至2017年3月间对13895只苍蝇进行形态学检查，鉴定出了虻类（虻属占0.34%、鞍斑虻属占0.03%、麻虻属占0.01%、斑虻属占0.014%和距虻属占0.11%）。鉴定出两种厩螫蝇属物种；黑厩螫蝇（45.30%）和厩螫蝇（17.29%），以及两种舌蝇属物种，即冈比亚舌蝇指名亚种（0.46%）和刺舌蝇（0.51%）。通过核苷酸序列的BLAST搜索进一步确认了这些鉴定结果。28S rDNA基因序列的中介邻接网络表明所检查的苍蝇物种在遗传上是不同的。所有捕获苍蝇的表观密度在平均温度26 - 28℃、湿度>80%且月降雨量为150 - 220毫米时最高。观察到苍蝇的分布随着植被密度的增加而增加，在人口密度相对较高（>100/平方公里）的地区减少。
苍蝇28S rDNA基因的种群指数表明，核DNA片段分析可能为这些苍蝇的分子生态学提供更多信息。鉴定苍蝇物种并评估其影响对于非洲动物锥虫病传播的分布和监测至关重要。
