Åberg Malin, Emanuelson Ulf, Troell Karin, Björkman Camilla
Department of Clinical Sciences, Swedish University of Agricultural Sciences, Box 7054, SE-750 07 Uppsala, Sweden.
Department of Microbiology, National Veterinary Institute, SE-751 89 Uppsala, Sweden.
Vet Parasitol X. 2019 Apr 7;1:100010. doi: 10.1016/j.vpoa.2019.100010. eCollection 2019 May.
In order to investigate the infection dynamics of and , a Swedish dairy farm known to be free of was recruited for a one-year study. Fecal samples were collected every four weeks (a total of 13 occasions) from 20 randomly selected calves younger than 65 days. A total of 238 feces samples were collected directly from the rectum and then examined with immunofluorescence microscopy; those positive for spp. oocysts were further processed by molecular species determination. Oocysts were found in 92 samples, and in 72 of these the species was successfully determined: 87.5% 9.7% and 2.8% a mix of both species. No was found. The prevalence of shedding calves was highest at ages 4 and 5 weeks; however, the feces with the highest oocyst per gram (OPG) were registered at 2-4 weeks of age. This is earlier than what has been found in most other studies, indicating that the infection dynamics of may be affected by the presence of . The OPG for the positive calves ranged from 200 to 1.1 × 10 (geometric mean 6.88 × 10). The youngest calf in which was identified was 5 days old, and the youngest calf in which was identified was 15 days old. Calves' housing type and seasonality were not associated with differences in the shedding of oocysts. Furthermore, there was no association between the presence of diarrhea and oocyst shedding.
为了研究[具体寄生虫名称1]和[具体寄生虫名称2]的感染动态，招募了一个已知无[具体寄生虫名称1]的瑞典奶牛场进行为期一年的研究。每四周（共13次）从20头随机挑选的65日龄以下犊牛采集粪便样本。总共直接从直肠采集了238份粪便样本，然后用免疫荧光显微镜检查；对[具体寄生虫名称1]属卵囊呈阳性的样本进一步进行分子物种鉴定。在92份样本中发现了卵囊，其中72份成功鉴定出物种：87.5%为[具体寄生虫名称1]，9.7%为[具体寄生虫名称2]，2.8%为两种物种的混合。未发现[具体寄生虫名称3]。排虫犊牛的患病率在4周龄和5周龄时最高；然而，每克粪便中卵囊数（OPG）最高的粪便记录于2 - 4周龄。这比大多数其他研究中发现的时间更早，表明[具体寄生虫名称1]的感染动态可能受[具体寄生虫名称2]的存在影响。阳性犊牛的OPG范围为200至1.1×10（几何平均值6.88×10）。鉴定出[具体寄生虫名称1]的最年幼犊牛为5日龄，鉴定出[具体寄生虫名称2]的最年幼犊牛为15日龄。犊牛的饲养类型和季节性与卵囊排出的差异无关。此外，腹泻的存在与卵囊排出之间没有关联。
