Anses, Niort laboratory, 60 rue de Pied de Fond, CS28440, 79024 Niort cedex, France.
Anses, Niort laboratory, 60 rue de Pied de Fond, CS28440, 79024 Niort cedex, France.
Vet Parasitol. 2014 May 28;202(3-4):301-4. doi: 10.1016/j.vetpar.2014.03.024. Epub 2014 Apr 1.
Cryptosporidium spp. is an important agent of neonatal diarrhoea in goat kids. Little is known about its molecular characterization in adult goats. A longitudinal study was set up to identify the species excreted by adult goats around parturition. Individual faecal samples were collected from 20 pregnant adult goats between 1 and 5 years old in one flock. Samplings began 3 weeks before the estimated kidding date and were done weekly until kidding and for 2 weeks after kidding. Cryptosporidium oocysts were concentrated from 15 g of faeces using a caesium chloride (CsCl) method. Oocyst output was determined using a direct immunofluorescent antibody test (IFAT). Genomic DNA was extracted from each CsCl-concentrated faecal sample positive by IFAT and submitted to a nested PCR-RFLP on the SSU rDNA gene followed by sequencing to identify the isolates at species level. According to their kidding date, goats were sampled between 4 and 8 times. Sixteen goats, out of the eighteen which kidded, were found positive at least at one sampling date. Infection was asymptomatic. Prevalence of excretion was maximal 14 days before kidding with half of the goats excreting oocysts at this date. Excretion was higher before kidding than after kidding. Unexpected levels of excretion were observed with individual oocyst excretion ranging from 6 to 2.5 × 10(5) oocysts per gram of faeces. All isolates were identified as Cryptosporidium ubiquitum.
隐孢子虫是引起羔羊腹泻的重要病原体,然而关于成年山羊的分子特征研究却知之甚少。本研究建立了一个纵向研究,旨在确定即将分娩的成年山羊所排泄的隐孢子虫种类。从一个羊群中采集了 20 只 1-5 岁的怀孕成年山羊的个体粪便样本。采样于预产期前 3 周开始,每周一次,直到分娩,并在分娩后进行两周。采用氯化铯(CsCl)方法从 15 克粪便中浓缩隐孢子虫卵囊。采用直接免疫荧光抗体试验(IFAT)确定卵囊产量。用 IFAT 检测到的每个 CsCl 浓缩粪便样本中提取基因组 DNA,进行小亚基核糖体 DNA(SSU rDNA)基因的嵌套 PCR-RFLP,然后测序以确定种水平的分离株。根据产羔日期,山羊在 4 到 8 天内进行了采样。在 18 只产羔的山羊中,有 16 只至少在一个采样日期被检测为阳性。感染无症状。在分娩前 14 天,排泄的流行率最高,此时一半的山羊排泄卵囊。分娩前的排泄量高于分娩后的排泄量。个体卵囊排泄量从 6 到 2.5×10(5)个卵囊/克粪便不等,观察到了意外的排泄水平。所有分离株均鉴定为隐孢子虫 ubiquitum。