Molecular epidemiology of Cryptosporidium spp. in dairy cattle in Guangdong Province, South China | Parasitology | Cambridge Core (original) (raw)

Introduction

Cryptosporidium is an important protozoan parasite, mainly causing gastrointestinal disease in humans and animals, including livestock, companion animals and wildlife (Fayer, Reference Fayer2010). Among domestic animals, cattle are recognized as the most common mammalian species to be infected by Cryptosporidium, and preweaned calves are considered an important reservoir for zoonotic Cryptosporidium infections (Xiao and Feng, Reference Xiao and Feng2008; Xiao, Reference Xiao2010; Imre et al., Reference Imre, Lobo, Matos, Popescu, Genchi and Darabus2011). Contamination of cattle manure has led to several food-borne and water-borne outbreaks of human cryptosporidiosis (Blackburn et al., Reference Blackburn, Mazurek, Hlavsa, Park and Tillapaw2006; Baldursson and Karanis, Reference Baldursson and Karanis2011). Cryptosporidium infections frequently result in morbidity, weight loss and delayed growth, and sometimes mortality of young animals.

To date, 37 valid Cryptosporidium species and over 70 genotypes have been described (Ryan et al., Reference Ryan, Fayer and Xiao2014; Kváč et al., Reference Kváč, Havrdová, Hlásková, Daňová, Kanděra, Ježková, Vítovec, Sak, Ortega, Xiao, Modrý, Chelladurai, Prantlová and McEvoy2016; Zahedi et al., Reference Zahedi, Durmic, Gofton, Kueh, Austen, Lawson, Callahan, Jardine and Ryan2017; Čondlová et al., Reference Čondlová, Horčičková, Sak, Květoňová, Hlásková, Konečný, Stanko, McEvoy and Kváč2018; Kváč et al., Reference Kváč, Vlnatá, Ježková, Horčičková, Konečný, Hlásková, McEvoy and Sak2018). Four of them, namely Cryptosporidium parvum, Cryptosporidium bovis, Cryptosporidium andersoni and Cryptosporidium ryanae are the most common species that can infect cattle and cause bovine cryptosporidiosis. Occasionally, Cryptosporidium felis, Cryptosporidium hominis, Cryptosporidium suis, Cryptosporidium scrofarum and _C. suis_-like have also been detected in cattle (Trout and Santín, Reference Trout, Santín, Fayer and Xiao2008). Many studies conducted in industrialized nations demonstrate that the four common species have age-related distributions. Cryptosporidium parvum is mostly found in preweaned calves and is a significant cause of diarrhoea. Cryptosporidium bovis and C. ryanae usually infect postweaned calves and yearlings, although C. bovis is more prevalent than C. ryanae, and neither is associated with diarrhoea (Santín et al., Reference Santín, Trout and Fayer2008). In contrast, C. andersoni is commonly seen in adult cattle and has been associated with gastritis, reduced milk yield and poor weight gain (Esteban and Anderson, Reference Esteban and Anderson1995).

In China, Cryptosporidium infections have been reported in dairy cattle in Xinjiang, Ningxia, Gansu, Shaanxi, Heilongjiang, Henan, Shandong, Hubei and other provinces (Liu et al., Reference Liu, Wang, Li, Zhang, Shu, Zhang, Feng, Xiao and Ling2009; Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_, Reference Wang, Wang, Sun, Zhang, Jian, Qi, Ning and Xiao2011_b_; Zhang et al., Reference Zhang, Wang, Yang, Zhang, Cao, Zhang, Hong, Liu and Shen2013, Reference Zhang, Tan, Zhou, Ni, Liu, Yang and Zhu2015; Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013, Reference Zhao, Wang, Zhang, Liu, Cao, Shen, Yang and Zhang2014; Cui et al., Reference Cui, Wang, Huang, Wang, Zhao and Luo2014; Huang et al., Reference Huang, Yue, Qi, Wang, Zhao, Li, Shi, Wang and Zhang2014; Ma et al., Reference Ma, Li, Zhao, Xu, Wu, Wang, Guo, Wang, Feng and Xiao2015; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015_a_, Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_; Fan et al., Reference Fan, Wang, Koehler, Hu and Gasser2017), but no information is available on the prevalence or genotypes of Cryptosporidium infections in dairy cattle in Guangdong Province. In this study, we conducted the first molecular epidemiological survey of dairy cattle in Guangdong Province to identify the infection rates and species distribution of Cryptosporidium.

Discussion

The overall Cryptosporidium prevalence in this study was 4.38%, which is lower than most rates reported in dairy cattle in Heilongjiang (17.33%, 257/1483), Anhui (14.9%, 52/350), Shanghai (12.5%, 55/440), Jiangsu (20.7%, 251/1215), Henan (13.0%, 276/2116), Xinjiang (16.0%, 82/514) and Shaanxi (5.24%, 122/2329) (Liu et al., Reference Liu, Wang, Li, Zhang, Shu, Zhang, Feng, Xiao and Ling2009; Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_, Reference Wang, Wang, Sun, Zhang, Jian, Qi, Ning and Xiao2011_b_; Chen and Huang, Reference Chen and Huang2012; Zhang et al., Reference Zhang, Wang, Yang, Zhang, Cao, Zhang, Hong, Liu and Shen2013; Zhao et al., Reference Zhao, Wang, Zhang, Liu, Cao, Shen, Yang and Zhang2014; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015a, Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_; Zhang et al., Reference Zhang, Tan, Zhou, Ni, Liu, Yang and Zhu2015), but higher than that in Ningxia (3.76%, 115/3054) (Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013; Huang et al., Reference Huang, Yue, Qi, Wang, Zhao, Li, Shi, Wang and Zhang2014; Cui et al., Reference Cui, Wang, Huang, Wang, Zhao and Luo2014; Qi et al., Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_). The infection rate of 6.4% in preweaned calves was lower than all previously reported studies, in which the prevalence was 10.22–47.68% (Wang et al., Reference Wang, Wang, Sun, Zhang, Jian, Qi, Ning and Xiao2011_b_; Zhang et al., Reference Zhang, Wang, Yang, Zhang, Cao, Zhang, Hong, Liu and Shen2013; Huang et al., Reference Huang, Yue, Qi, Wang, Zhao, Li, Shi, Wang and Zhang2014; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015_a_, Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_; Fan et al., Reference Fan, Wang, Koehler, Hu and Gasser2017). However, the infection rate in postweaned calves (6.19%) was higher than that in Heilongjiang (5.5%) (Liu et al., Reference Liu, Wang, Li, Zhang, Shu, Zhang, Feng, Xiao and Ling2009), but lower than that in Henan (11.3%) and Xinjiang (16.2%) (Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015_a_). Many factors, including specimen size, diagnostic technique, management system, season and geographic area, may be responsible for the differences in the prevalence of Cryptosporidium observed in different areas of China. These results were also consistent with previous studies, which showed that the prevalence of Cryptosporidium was higher in preweaned calves than in any other age group (Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_, Reference Wang, Wang, Sun, Zhang, Jian, Qi, Ning and Xiao2011_b_; Huang et al., Reference Huang, Yue, Qi, Wang, Zhao, Li, Shi, Wang and Zhang2014; Zhang et al., Reference Zhang, Tan, Zhou, Ni, Liu, Yang and Zhu2015) (Table 1).

Cryptosporidium andersoni is the predominant species in postweaned calves and adult cattle, which had been confirmed in China, Mongolia, Egypt and some European countries (Burenbaatar et al., Reference Burenbaatar, Bakheit, Plutzer, Suzuki, Igarashi, Ongerth and Karanis2008; Ondráčková et al., Reference Ondráčková, Kváč, Sak, Květoňová and Rost2009; Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_; Amer et al., Reference Amer, Zidan, Adamu, Ye, Roellig, Xiao and Feng2013; Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013; Ma et al., Reference Ma, Li, Zhao, Xu, Wu, Wang, Guo, Wang, Feng and Xiao2015; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015a, Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_). In contrast, in other countries, C. bovis was considered the predominant species in postweaned calves (Enemark et al., Reference Enemark, Ahrens, Lowery, Thamsborg and Enemark2002; Feng et al., Reference Feng, Ortega, He, Das, Xu, Zhang, Fayer, Gatei, Cama and Xiao2007). Cryptosporidium andersoni was the only species detected in heifers and adult cattle in this study, which was identical to previous studies conducted in Heilongjiang, Shaanxi and Henan Provinces (Liu et al., Reference Liu, Wang, Li, Zhang, Shu, Zhang, Feng, Xiao and Ling2009; Wang et al., Reference Wang, Ma, Zhao, Lu, Wang, Zhang, Jian, Ning and Xiao2011_a_; Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013). The potential zoonotic transmission of C. andersoni is unknown, but the species has been isolated from humans with diarrhoea (Leoni et al., Reference Leoni, Amar, Nichols, Pedraza-Diaz and McLauchlin2006; Jiang et al., Reference Jiang, Ren, Yuan, Liu, Zhao, Liu, Chu, Pan, Cao, Lin and Shen2014).

Several studies have reported that zoonotic C. parvum is responsible for the majority of Cryptosporidium infections in preweaned calves (Santín et al., Reference Santín, Trout, Xiao, Zhou, Greiner and Fayer2004; Fayer et al., Reference Fayer, Santín, Trout and Greiner2006; Santín et al., Reference Santín, Trout and Fayer2008; Trout and Santín, Reference Trout, Santín, Fayer and Xiao2008; Amer et al., Reference Amer, Zidan, Adamu, Ye, Roellig, Xiao and Feng2013). However, other studies have shown that C. bovis is the species most commonly found in preweaned calves (Feng et al., Reference Feng, Ortega, He, Das, Xu, Zhang, Fayer, Gatei, Cama and Xiao2007; Silverlas et al., Reference Silverlas, Naslund, Bjorkman and Mattsson2010; Rieux et al., Reference Rieux, Chartier, Pors and Paraud2013). In the present study, C. bovis, rather than C. parvum, was the most abundant species in preweaned calves, which was in concordance with the results from Shaanxi, Heilongjiang, Henan and Hubei Provinces, as well as Shanghai (Wang et al., Reference Wang, Wang, Sun, Zhang, Jian, Qi, Ning and Xiao2011_b_; Zhang et al., Reference Zhang, Wang, Yang, Zhang, Cao, Zhang, Hong, Liu and Shen2013; Qi et al., Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_; Fan et al., Reference Fan, Wang, Koehler, Hu and Gasser2017), but differed from Xinjiang and Ningxia (Cui et al., Reference Cui, Wang, Huang, Wang, Zhao and Luo2014; Huang et al., Reference Huang, Yue, Qi, Wang, Zhao, Li, Shi, Wang and Zhang2014; Qi et al., Reference Qi, Wang, Jing, Wang, Wang and Zhang2015a, Reference Qi, Fang, Wang, Zhang, Wang, Du, Guo, Jia, Yao, Liu and Zhao2015_b_).

However, C. parvum was not detected in the present study, which was also reported in early studies from China and abroad (Maikai et al., Reference Maikai, Umoh, Kwaga, Lawal, Maikai, Cama and Xiao2011; Feng et al., Reference Feng, Karna, Dearen, Singh, Adhikari, Shrestha and Xiao2012; Murakoshi et al., Reference Murakoshi, Xiao, Matsubara, Sato, Kato, Sasaki, Fukuda, Tada and Nakai2012; Nguyen et al., Reference Nguyen, Fukuda, Tada, Sato, Duong, Nguyen and Nakai2012; Abeywardena et al., Reference Abeywardena, Jex, Koehler, Rajapakse, Udayawarna, Haydon, Stevens and Gasser2014; Wegayehu et al., Reference Wegayehu, Karim, Anberber, Adamu, Erko, Zhang and Tilahun2016; Fan et al., Reference Fan, Wang, Koehler, Hu and Gasser2017). The reason for the absence of C. parvum remains unclear. The failure to detect C. parvum in preweaned calves in Guangdong Province suggests that the dairy cattle in this province have low zoonotic potential for the transmission of Cryptosporidium to humans. However, larger sample of dairy cattle from this province should be analysed by PCR to confirm the findings of the present study.

To date, 21 MLST subtypes have been identified in C. andersoni isolates from animals, 17 of which occur in cattle (Feng et al., Reference Feng, Yang, Ryan, Zhang, Kvác, Koudela, Modrý, Li, Fayer and Xiao2011; Wang et al., Reference Wang, Jian, Zhang, Ning, Liu, Zhao, Feng, Qi, Wang, Lv, Zhao and Xiao2012; Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013; Qi et al., Reference Qi, Wang, Jing, Jian, Ning and Zhang2016). In the present study, the MLST subtype A4,A4,A4,A1 was the most prevalent subtype in dairy cattle in Guangdong, which was in agreement with the finding in Heilongjiang and other areas of China (Wang et al., Reference Wang, Jian, Zhang, Ning, Liu, Zhao, Feng, Qi, Wang, Lv, Zhao and Xiao2012; Zhao et al., Reference Zhao, Wang, Zhang, Liu, Cao, Shen, Yang and Zhang2014), whereas subtype A2,A4,A2,A1 was predominant in dairy cattle in Xinjiang and A1,A4,A4,A1 in Shaanxi (Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013; Qi et al., Reference Qi, Wang, Jing, Jian, Ning and Zhang2016). These differences may be related to the number of samples examined and geographic segregation. MLST subtype A2,A5,A2,A1 was found for the first time in cattle in this study, which was also identified in sheep, and further suggested that C. andersoni might circulate between cattle and sheep (Wang et al., Reference Wang, Jian, Zhang, Ning, Liu, Zhao, Feng, Qi, Wang, Lv, Zhao and Xiao2012).

In this study, the samples successfully amplified at all four loci were included in the LD analysis, which showed that C. andersoni isolated from dairy cattle in Guangdong Province had a clonal genetic population structure. The result differed from previous findings that C. andersoni population in cattle from Xinjiang and other geographical regions of China had an epidemic genetic structure (Wang et al., Reference Wang, Jian, Zhang, Ning, Liu, Zhao, Feng, Qi, Wang, Lv, Zhao and Xiao2012; Qi et al., Reference Qi, Wang, Jing, Jian, Ning and Zhang2016). However, it was consistent with C. andersoni isolates in cattle from Shaanxi and Heilongjing Provinces (Zhao et al., Reference Zhao, Ren, Gao, Bian, Hu, Cong, Lin, Wang, Qi, Qi, Zhu and Zhang2013; Zhao et al., Reference Zhao, Wang, Zhang, Liu, Cao, Shen, Yang and Zhang2014). A clonal genetic population structure indicated that the prevalence of C. andersoni in cattle in Guangdong Province was not attributable to the introduction of cattle.

In conclusion, Cryptosporidium is common in dairy cattle in Guangdong province. Sequence analysis revealed the presence of C. andersoni, C. bovis and C. ryanae infection, with C. andersoni as the most prevalent species. Three MLST subtypes of C. andersoni were identified, and subtype A2,A5,A2,A1 was found for the first time in cattle. Cryptosporidium andersoni in dairy cattle in Guangdong presented a clonal genetic structure. The findings in this study provided valuable basic data for developing strategies and measures to control Cryptosporidium infection in dairy cattle and evaluate the risk of Cryptosporidium infection to humans.