Enterocytozoon bieneusi genotypes in Tibetan sheep and yaks

Abstract

Few studies have been conducted on the distribution of Enterocytozoon bieneusi genotypes in Tibetan sheep and yaks, which live outdoors in extreme climate with high altitude. In this study, fecal specimens from 312 Tibetan sheep and 554 yaks in Qinghai, China, were collected and examined for E. bieneusi by PCR-sequence analysis of the ribosomal internal transcribed spacer. Among them, 73 (23.4%) specimens from Tibetan sheep and 40 (7.2%) from yaks were positive for E. bieneusi. There were eight E. bieneusi genotypes in Tibetan sheep, including three known ones (BEB6, COS-I, and NESH5) and five novel ones (named as CHS13-CHS17). Similarly, seven E. bieneusi genotypes were found in yaks, including five known ones (J, BEB4, BEB6, COS-I, and NESH5) and two novel ones (named as CHN13 and CHN14). Most of the E. bieneusi genotypes and all frequent ones identified in the study belonged to group 2. One new subgroup of genotypes was identified within group 1. The distribution of E. bieneusi genotypes was different between Tibetan sheep and yaks, with BEB6 as the dominant one (42.5%) in Tibetan sheep and J as the dominant one (47.5%) in yaks. These data support the occurrence of host adaptation among E. bieneusi genotypes within group 2.

Prevalence and genetic diversity of Enterocytozoon bieneusi in sheep in China

“…Additionally, the prevalence rate of E. bieneusi in Heilongjiang in the present study (51.7%) was higher than the previously reported rate of 22.5% found using the same method [ 23 ]. However, compared to studies that used different ITS primers, prevalence rates in the present study in Henan (0%), Inner Mongolia (2.9%) and Qinghai (9.2%) were lower than previous reports in Henan (51.9%) [ 25 ], Inner Mongolia (69.3%) [ 24 ] and Qinghai (23.4%) [ 26 ], but higher than previous reports in Heilongjiang (4.4, 13.9 and 25.0%) [ 19 , 22 , 25 ]. The differences between our study and previous studies may be due to differences in detection methods, sampling sites, sampling seasons, sheep age groups or sheep densities.…”

“…In the present study, a higher prevalence of E. bieneusi was detected in lambs (23.5%) than in adults (14.6%), which is consistent with many previous studies in Brazil and China [ 21 , 22 , 24 – 26 ]. The prevalence of E. bieneusi in lambs under one year of age was 23.5%, which is similar to the findings of a previous study in Heilongjiang (18.2%) [ 22 ], but lower than reported in previous studies in other parts of China [ 25 , 26 ] and in Sweden [ 28 ]. The prevalence in pre-weaned lambs (25.0%) was also similar to a study by Li et al [ 19 ] in Heilongjiang (20.0%) but was significantly lower than previous reports by Ye et al [ 24 ] in Inner Mongolia (77.8%).…”

“…However, the epidemiology of E. bieneusi has rarely been reported in sheep. To date, a few studies have reported E. bieneusi infection in sheep in Brazil [ 21 ], China [ 19 , 22 – 26 ], Iran [ 27 ] and Sweden [ 28 ] (Table 1 ). Several genotypes were identified in these studies, including genotypes D, BEB6, BEB7, EbpC, O, I, Peru6, NESH1-NESH 6, CS-4, CM7, COS-I-COS-VII and CHS1-CHS12 [ 7 , 22 , 23 , 25 ].…”

“…In China, E. bieneusi infections have been reported in sheep in five provinces, including Heilongjiang, Henan, Inner Mongolia, Liaoning and Qinghai Province, with infection rates ranging between 4.4–69.3% [ 19 , 22 – 26 ] (Table 1 ). At the end of 2016, China had the largest number of sheep in the world ( http://www.fao.org/faostat/en/#data/QA ), with most being bred in northern areas.…”

Molecular Characterization and Phylogenetic Analysis of Enterocytozoon bieneusi in Lambs in Oromia Special Zone, Central Ethiopia

“…Similar rate of infection was reported for E. bieneusi in sheep in Northeast China (13.9%, 68/489) (11), Southwest China (10.6%, 70/661) (12), and Egypt (11.2%, 10/89) (13); while lower infection rates were detected in sheep in East-central China (3.4%, 28/832) (14) and Slovakia (0/33) (15). However, a higher prevalence of E. bieneusi was found in Inner Mongolian (China) lambs (77.8%, 126/162) (16), Swedish lambs (68%, 49/72) (17), Brazilian sheep (19.2%, 24/125) (18), and in sheep from some other studies in China (19)(20)(21)(22). The differences in the prevalence are likely due to differences in the geographic and ecological setup.…”