Amdouni Yosra, Rouatbi Mariem, Lassoued Narjess, Rekik Mourad, Gharbi Mohamed
Laboratoire de Parasitologie, Univ. Manouba, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Ecole Nationale de Médecine Vétérinaire de Sidi Thabet, 2020, Sidi Thabet, Tunisia.
Laboratory of Animal Production and Forages, National Institute of Agronomic Research of Tunisia (INRAT), Carthage University, Tunis, Tunisia.
Acta Parasitol. 2019 Dec;64(4):821-828. doi: 10.2478/s11686-019-00105-0. Epub 2019 Aug 15.
The aim of this study was to estimate the seroprevalence and molecular prevalence and perform a molecular identification of Neospora caninum in semen of Tunisian rams.
A total of 92 blood samples were collected from four farms located in four Tunisian governorates (Jendouba, Kairouan, Zaghouan and Ben Arous) and samples were screened with a commercial ELISA kit for N. caninum antibodies. For the same rams, semen samples were collected and tested for the presence of N. caninum ITS1 gene using PCR. Five amplicons were randomly selected for sequencing. A phylogenetic tree was constructed to compare the partial sequences of the ITS1 gene with sequences deposited in GenBank.
The seroprevalence of N. caninum infection was 25% (23/92) and PCR revealed that the molecular infection prevalence in semen was 11.95% (11/92). Kappa test showed an average agreement between seroprevalence and parasite prevalence in semen (κ = 0.44). The highest molecular prevalence was for rams that accomplished more than two mating seasons (21.0 ± 12.1%) compared to those performed less than two mating seasons and yearling individuals (4.0 ± 5.5%) (P = 0.01). There were no differences in N. caninum molecular prevalence according to either breed or locality. Comparison of the partial sequences of the ITS1 gene revealed 99-100% similarity with those deposited in GenBank.
To the best of our knowledge, this is the first detection and molecular identification of N. caninum in semen from rams in North Africa. Our findings indicate that N. caninum infection rate was high in rams.
本研究旨在估计突尼斯公羊精液中犬新孢子虫的血清阳性率和分子感染率，并对其进行分子鉴定。
从突尼斯四个省（杰尔巴、凯鲁万、扎古万和本·阿鲁斯）的四个农场采集了92份血液样本，并用商用ELISA试剂盒检测犬新孢子虫抗体。对于同一批公羊，采集精液样本，采用PCR检测犬新孢子虫ITS1基因的存在情况。随机选择五个扩增子进行测序。构建系统发育树，将ITS1基因的部分序列与GenBank中保存的序列进行比较。
犬新孢子虫感染的血清阳性率为25%（23/92），PCR检测显示精液中的分子感染率为11.95%（11/92）。Kappa检验显示血清阳性率与精液中寄生虫感染率之间的平均一致性（κ = 0.44）。完成两个以上交配季节的公羊分子感染率最高（21.0 ± 12.1%），而交配季节少于两个的公羊和一岁公羊分子感染率较低（4.0 ± 5.5%）（P = 0.01）。犬新孢子虫的分子感染率在品种和产地方面均无差异。ITS1基因部分序列的比较显示与GenBank中保存的序列相似度为99 - 100%。
据我们所知，这是首次在北非公羊精液中检测到犬新孢子虫并进行分子鉴定。我们的研究结果表明突尼斯公羊中犬新孢子虫感染率较高。
