Ebiyo Adinew, Haile Geremew
Sibu Sire District Livestock Development Office, Nekemte, Ethiopia.
School of Veterinary Medicine, Wollega University, Nekemte, Ethiopia.
Vet Med Int. 2022 Feb 17;2022:1468242. doi: 10.1155/2022/1468242. eCollection 2022.
Cryptosporidiosis, caused by a protozoan parasite of the genus , is a zoonotic disease that affects young animals and humans. The study was conducted from October 2020 to May 2021, with the objectives of estimating the prevalence of infection in calves and assessing the associated risk factors in Nekemte town, Ethiopia.
A cross-sectional study was adopted during the study period. Initially, 35 dairy farms were selected using a systematic study approach from which a total of 384 calves under the age of 12 months (75 calves from intensive, 51 from semi-intensive, and 258 from extensive dairy farms) were selected purposively for fecal sample collection. Fecal samples were collected directly from the rectum of each calf and tested for oocysts using Sheather's flotation and a modified Ziehl-Neelsen staining procedure. The data were analyzed using STATA statistical software version 13.
infection was found in 53 of the 384 calves investigated, with an overall prevalence of 13.8% (95% CI = 8.1-17.6). Logistic regression analysis on the risk factors showed that types of farm, age, body condition scores, fecal consistency, types of feed, source of water, and farm hygiene were found to have a statistically significant influence on the shedding of oocysts by the calves ( < 0.05). Calves under the age of six months had a higher likelihood (OR = 2.7, 95% CI = 1.0-4.2, < 0.001) of shedding the oocysts than the calves of 6 to 12 months of age. It was also confirmed that calves with poor body condition scores had a higher likelihood (OR = 2.6, 95% CI = 1.2-3.7, =0.024) of shedding the oocysts than other ones. The likelihood of shedding a oocyst by the diarrheic calves was higher than by the nondiarrheic ones (OR = 3.1, < 0.001). The infection was 2.6 times highest (16.8%, 31/185, 95% CI = 14.5-19.1, OR = 2.6, =0.028) in calves feeding on grass alone, followed by milk and grass (15%) and milk (4.2%). Similarly, it was 2.2 times higher (18.5%, OR = 2.2, and =0.002) in calves drinking river water than in calves drinking tap water. Moreover, calves kept under poor hygiene were more likely to shed oocysts (OR = 2.8, =0.001) than calves kept under good hygiene.
In conclusion, cryptosporidiosis is one of the health problems of calves in and around Nekemte town, East Wollega zone. Our findings confirmed that risk factors such as types of farm, age, body condition scores, fecal consistency, types of feed, water source, and farm hygienic status were found to have a significant effect on the occurrence of infection in the calves. While the molecular-based study is required to be carried out aiming at species identification and the epidemiology of the parasite, particular attention should be paid to the control of the disease in the study area.
隐孢子虫病由隐孢子虫属原生动物寄生虫引起，是一种影响幼畜和人类的人畜共患病。本研究于2020年10月至2021年5月进行，目的是估计埃塞俄比亚内克姆特镇犊牛隐孢子虫感染率，并评估相关危险因素。
在研究期间采用横断面研究。最初，采用系统抽样方法从35个奶牛场中选取，共选取384头12月龄以下的犊牛（75头来自集约化养殖场，51头来自半集约化养殖场，258头来自粗放式奶牛场）进行粪便样本采集。粪便样本直接从每头犊牛的直肠采集，使用Sheather漂浮法和改良的齐尔-尼尔森染色程序检测隐孢子虫卵囊。使用STATA 13统计软件对数据进行分析。
在384头被调查的犊牛中，有53头检测出隐孢子虫感染，总体感染率为13.8%（95%置信区间=8.1-17.6）。对危险因素的逻辑回归分析表明，养殖场类型、年龄、身体状况评分、粪便稠度、饲料类型、水源和养殖场卫生状况对犊牛隐孢子虫卵囊排出有统计学显著影响（P<0.05）。6月龄以下的犊牛排出卵囊的可能性（比值比=2.7，95%置信区间=1.0-4.2，P<0.001）高于6至12月龄的犊牛。还证实身体状况评分差的犊牛排出隐孢子虫卵囊的可能性（比值比=2.6，95%置信区间=1.2-3.7，P=0.024）高于其他犊牛。腹泻犊牛排出隐孢子虫卵囊的可能性高于非腹泻犊牛（比值比=3.1，P<0.001）。仅以草为食的犊牛感染率最高（16.8%，31/185，95%置信区间=14.5-19.1，比值比=2.6，P=0.028），其次是牛奶和草（15%）和牛奶（4.2%）。同样，饮用河水的犊牛感染率比饮用自来水的犊牛高2.2倍（18.5%，比值比=2.2，P=0.002）。此外，卫生条件差的犊牛比卫生条件好的犊牛更易排出隐孢子虫卵囊（比值比=2.8，P=0.001）。
总之，隐孢子虫病是东沃莱加区内克姆特镇及周边地区犊牛的健康问题之一。我们的研究结果证实，养殖场类型、年龄、身体状况评分、粪便稠度、饲料类型、水源和养殖场卫生状况等危险因素对犊牛隐孢子虫感染的发生有显著影响。虽然需要开展基于分子的研究以进行寄生虫的种类鉴定和流行病学研究，但在研究区域应特别注意该病的防控。
