College of Veterinary Medicine, Federal University of Agriculture, P.M.B. 2240 Abeokuta, Ogun state, Nigeria; Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Prince Edward Island C1A 4P3, Canada.
College of Veterinary Medicine, Federal University of Agriculture, P.M.B. 2240 Abeokuta, Ogun state, Nigeria.
Infect Genet Evol. 2019 Jun;70:53-60. doi: 10.1016/j.meegid.2019.02.017. Epub 2019 Feb 21.
Giardia duodenalis is an intestinal flagellated protozoan parasite that is infectious to humans and a wide range of animals worldwide. While varying prevalence rates have been reported in pigs worldwide, there are currently no published reports on the genotypes of Giardia infecting pigs in any African country. The present study is on the prevalence and genotypes of G. duodenalis in 209 pigs raised on four farms in Ogun State Nigeria. Using an enzyme-linked immunosorbent assay (ELISA) kit, Giardia duodenalis coproantigens were detected on all farms and in 25.4% (53/209) of pigs sampled. However, there was no significant influence (p > 0.05) of age, sex and stool consistencies of the pigs on the distribution of the infection. Genotyping of Giardia duodenalis in all ELISA-positive samples, achieved by the amplification of the small subunit ribosomal RNA (ssu rRNA), glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi) and beta giardin (bg) genes, identified 14 and 37 assemblage B and E isolates respectively while mixed infection by both assemblages was recorded in two isolates. Novel nucleotide substitutions were identified in four assemblage B isolates at the ssu rRNA locus. Genetic diversity was observed among the assemblage B isolates after multiple alignment analyses of the gdh, tpi and bg sequences whereby sub-assemblages BII (n = 2), BIII (n = 9) and BIV (n = 3) were identified. The assemblage B isolates from pigs in this study were phylogenetically related to isolates from humans, marmoset and cattle while the assemblage E isolates were related to isolates from sheep, goats and cattle. These findings suggest that pigs in southwest Nigeria predominantly harbour G. duodenalis isolates that could be infectious to other animal species and to a lesser extent, isolates that may be of zoonotic importance.
十二指肠贾第鞭毛虫是一种感染人和世界各地多种动物的肠道鞭毛原生动物寄生虫。虽然在全球范围内报道了不同的流行率，但目前还没有关于任何非洲国家感染猪的贾第鞭毛虫基因型的发表报告。本研究是在尼日利亚奥贡州的四个农场饲养的 209 头猪中进行的，检测了贾第鞭毛虫的流行率和基因型。使用酶联免疫吸附试验（ELISA）试剂盒，在所有农场和 25.4%（53/209）的采样猪中检测到了十二指肠贾第鞭毛虫的粪抗原。然而，猪的年龄、性别和粪便稠度对感染的分布没有显著影响（p>0.05）。对所有 ELISA 阳性样本进行的贾第鞭毛虫基因分型，通过扩增小亚基核糖体 RNA（ssu rRNA）、谷氨酸脱氢酶（gdh）、磷酸丙糖异构酶（tpi）和β-微管蛋白（bg）基因实现，分别鉴定出 14 个和 37 个 B 组和 E 组分离株，而在两个分离株中记录到了两种虫株的混合感染。在 ssu rRNA 基因座，四个 B 组分离株中发现了四个新的核苷酸取代。在 gdh、tpi 和 bg 序列的多重比对分析后，观察到 B 组分离株之间存在遗传多样性，其中鉴定出 BII（n=2）、BIII（n=9）和 BIV（n=3）亚组。本研究中来自猪的 B 组分离株与来自人类、狨猴和牛的分离株在系统发育上有关，而 E 组分离株与来自绵羊、山羊和牛的分离株有关。这些发现表明，尼日利亚西南部的猪主要携带可能感染其他动物物种的十二指肠贾第鞭毛虫分离株，在较小程度上，也可能携带具有人畜共患重要性的分离株。
