Cryptosporidium Species and C. parvum Subtypes in Farmed Bamboo Rats

Bamboo rats (Rhizomys sinensis) are widely farmed in Guangdong, China, but the distribution and public health potential of Cryptosporidium spp. in them are unclear. In this study, 724 fecal specimens were collected from bamboo rats in Guangdong Province and analyzed for Cryptosporidium spp. using PCR and sequence analyses of the small subunit rRNA gene. The overall detection rate of Cryptosporidium spp. was 12.2% (88/724). By age, the detection rate in animals under 2 months (23.2% or 13/56) was significantly higher than in animals over 2 months (11.2% or 75/668; χ2 = 6.95, df = 1, p = 0.0084). By reproduction status, the detection rate of Cryptosporidium spp. in nursing animals (23.1% or 27/117) was significantly higher than in other reproduction statuses (6.8% or 4/59; χ2 = 7.18, df = 1, p = 0.0074). Five Cryptosporidium species and genotypes were detected, including Cryptosporidium bamboo rat genotype I (n = 49), C. parvum (n = 31), Cryptosporidium bamboo rat genotype III (n = 5), C. occultus (n = 2), and C. muris (n = 1). The average numbers of oocysts per gram of feces for these Cryptosporidium spp. were 14,074, 494,636, 9239, 394, and 323, respectively. The genetic uniqueness of bamboo rat genotypes I and III was confirmed by sequence analyses of the 70 kDa heat shock protein and actin genes. Subtyping C. parvum by sequence analysis of the 60 kDa glycoprotein gene identified the presence of IIoA15G1 (n = 20) and IIpA6 (n = 2) subtypes. The results of this study indicated that Cryptosporidium spp. are common in bamboo rats in Guangdong, and some of the Cryptosporidium spp. in these animals are known human pathogens.

Den habitat selection of the chinese bamboo rat (Rhizomys sinensis) in Northern Guangxi China

A habitats comprises a range of environmental features that provide adequate resources for wildlife to survive. Consequently, the criteria of habitat selection by animals, combines a wider spectrum of both environmental and other factors, with major prerequisites being food resources, availability of shelter and suitable conditions for reproduction. The den habitat selection of the Chinese bamboo rat (Rhizomys sinensis) was studied in Yuanbaoshan Nature Reserve, Guangxi China. The Vanderloeg and Scavia selectivity index (Ei) indicates that the Chinese bamboo rat shows a preference for all habitat features except for slope, slope position and distance to water (P>0.05). Chi-square goodness of fit test showed that canopy density, shelter from wind, distance between shrubs, shrub density, elevation, southern aspect, human disturbance and food abundance, were the preferred features (P less than 0.05). With regards to human disturbance, the Chinese bamboo rat preferred places >1000 m away from human habitation. An eastern and southern sloping direction, a 20°^~40° slope and an elevation range of >1800m were more frequently used. The Chinese bamboo rat prefers habitats lying above 1000m in elevation with high shrub density (with shrub separation under 0.1m). Principle component analysis indicates that concealment factors, geographical factors, interference factors, food factors, and water factors affect the den habitat character of the Chinese bamboo rat. Our results support the notion that the habitat preferences of the Chinese bamboo rat are a tradeoff between suitable habitat features and avoidance of potential human interactions.