Laboratoire de Parasitologie, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, École Nationale de Médecine Vétérinaire de Sidi Thabet, Univ. Manouba, Ariana, Tunisia.
Regional Slaughterhouse of Béja, Béja, Tunisia.
Transbound Emerg Dis. 2018 Aug;65(4):976-982. doi: 10.1111/tbed.12828. Epub 2018 Feb 8.
Neosporosis, caused by the protozoan Neospora caninum, is a major cause of reproductive failure in ruminants causing enormous economic losses. The objective of this study was to estimate the infection rate and molecular identification of N. caninum in Tunisian cattle and sheep. A total number of 348 meat samples were collected from 150 cows and 198 ewes slaughtered in the regional slaughterhouse of Béja (North-west Tunisia) and tested for the presence of N. caninum ITS1 gene using PCR followed by sequencing of some PCR products. A phylogenetic tree was then constructed to compare the partial sequences of the ITS1 gene with GenBank sequences. The overall molecular infection prevalence of N. caninum was significantly higher in cattle than in sheep (22 and 10.6%, respectively, p = .003). In sheep, the highest prevalence was observed in the northern Béja locality (31.2 ± 16.1), with the Noire de Thibar breed as the most infected sheep breed (31.7 ± 14.2%) (p < .001). In cattle, there were no differences in the molecular prevalence of N. caninum according to breeds and localities. The association between age and N. caninum molecular prevalence was statistically significant in both species; the highest prevalence was observed in sheep of more than one year of age (19.4 ± 9.1%), and in cattle between two and eight years of age (28.8 ± 10.9%). Comparison of the partial sequences of the ITS1 gene revealed 96%-100% similarity among our N. caninum amplicon and those deposited in GenBank. To our knowledge, this is the first detection and molecular identification of N. caninum in sheep and cattle in North Africa. This information is pertinent in designing control programmes that would reduce economic losses in the livestock industry.
刚地弓形虫病由原生动物刚地弓形虫引起，是反刍动物繁殖失败的主要原因，给养殖业带来了巨大的经济损失。本研究的目的是估计突尼斯牛和羊中刚地弓形虫的感染率和分子鉴定。从贝贾地区屠宰场（突尼斯西北部）屠宰的 150 头牛和 198 只羊中采集了 348 份肉样，采用 PCR 检测刚地弓形虫 ITS1 基因的存在，然后对一些 PCR 产物进行测序。随后构建了一个系统发育树，将 ITS1 基因的部分序列与 GenBank 序列进行比较。牛的总体分子感染率明显高于羊（分别为 22%和 10.6%，p=0.003）。在绵羊中，北部贝贾地区的患病率最高（31.2±16.1），诺雷·德·蒂巴尔品种的绵羊感染率最高（31.7±14.2%）（p<0.001）。在牛中，根据品种和地区，刚地弓形虫的分子感染率没有差异。两种动物的年龄与刚地弓形虫分子感染率之间存在统计学显著关联；年龄超过 1 岁的绵羊感染率最高（19.4±9.1%），2 至 8 岁的牛感染率最高（28.8±10.9%）。ITS1 基因部分序列的比较表明，我们的刚地弓形虫扩增子与 GenBank 中储存的扩增子之间具有 96%-100%的相似性。据我们所知，这是首次在北非的绵羊和牛中检测和鉴定刚地弓形虫。这些信息对于制定控制计划以减少畜牧业的经济损失具有重要意义。
