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Zhang X.,University of South China | Zhang X.,Guangdong Entomological Institute South China Institute of Endangered Animals | Li L.,University of South China | Bai Y.,University of South China | And 3 more authors.

Summary: Dynamic simulated microgravity (SMG) culture systems provide environments that stimulate stem cell proliferation and differentiation. However, the effect of SMG on spermatogonial stem cells (SSCs) remains unclear. Here, we used a rotating cell culture system (RCCS) to determine its effect on mouse SSC proliferation and differentiation. SSCs were enriched from mouse pub testis and cocultured with Sertoli cell feeders pre-treated with mitomycin C on fibrin scaffolds in a rotary bioreactor for 14 days. Our results show that mouse SSCs cultured in a rotary bioreactor exhibited enhanced proliferation surpassing those cultured in static conditions, although SSC cultures in SMG underwent a growth lag at initial 3 days. After 14 days, mouse SSCs and feeders grew into cell aggregates with average diameters of 242.63 ± 16.53 μm compared with those in conventional static culture (49.51 ± 15.64 μm). Related detection revealed that proliferating SSCs in SMG remained undifferentiated, maintained clone-forming capacity and were capable of differentiation into round spermatids with flagella. The growth characteristics of mouse SSCs in RCCS suggest that the resulting aggregates are similar to native in vivo cells. Rotary bioreactors that create SMG environments may be an alternative to conventional systems for the clinical application of SSCs. © 2013 Blackwell Verlag GmbH. Source

Gong S.-P.,Guangdong Entomological Institute South China Institute of Endangered Animals | Yang D.-D.,Central South University of forestry and Technology | Chen Y.-H.,Mangshan Nature Museum | Lau M.,Kadoorie Farm and Botanic Garden | Wang F.-M.,Guangdong Provincial Wildlife Rescue Center

The Endangered Mangshan pit viper Protobothrops mangshanensis is endemic to the Nanling Mountain Range of China. It has been targeted for exploitation to satisfy the international pet trade and zoological collections since it was described. Long-term intensive exploitation and habitat destruction have resulted in drastic reductions in wild populations, pushing this rare species towards extinction. Since 1990 only limited investigations have been conducted and the most optimistic estimation of the population size was 300-500 individuals, in 2000. Since then, however, there have been no updates on the population status of this snake in the wild. To provide baseline data for effective conservation of this species we conducted a study of its status and distribution, during 2007-2010. Only eight individuals were found during fieldwork and we documented the illegal harvesting of >30. The total population of the species was estimated to be 462, occupying c. 105 km 2 in the Nanling Mountain Range. The black market price of a Mangshan pit viper is currently >USD 1,000 kg-1 and illegal trade has led to over-harvesting, which is the greatest threat to the species. Our study indicates that protected areas cannot effectively protect this pit viper if the trade in this species cannot be controlled. Based on the results of our study we present five recommendations for conservation of the species. Copyright © Fauna & Flora International 2013. Source

Hua L.,Guangdong Entomological Institute South China Institute of Endangered Animals | Wang F.,Guangdong Provincial Wildlife Rescue Center | Gong S.,Guangdong Entomological Institute South China Institute of Endangered Animals | Ge Y.,Guangdong Entomological Institute South China Institute of Endangered Animals | And 2 more authors.
Biochemical Genetics

The big-headed turtle (Platysternon megacephalum) is critically endangered because of overharvesting, illegal trade, and habitat destruction. Assessment of genetic variability in existing populations becomes very important to the taxonomy and conservation of this species. Here we describe 14 microsatellite loci isolated from an enriched genomic library of the big-headed turtle, and the polymorphisms of these loci were assessed in 28 individuals from Huizhou, Heyuan, Zhaoqing, and Shaoguan of Guangdong, China. The range of polymorphism information content is 0.305-0.738, and no evidence of significant linkage disequilibrium was found among any pairs of loci. These 14 new polymorphic microsatellite loci can be used in population genetics, taxonomy, phylogeography, behavior ecology, and conservation efforts of Platysternon megacephalum. © 2014 Springer Science+Business Media. Source

Gong S.,Guangdong Entomological Institute South China Institute of Endangered Animals | Wang F.,Guangdong Provincial Wildlife Rescue Center | Shi H.,Hainan Normal University | Zhou P.,Hainan Normal University | And 3 more authors.
Science of the Total Environment

Salmonella Pomona, a highly pathogenic serotype, can cause severe human salmonellosis, especially in children. Turtles and other reptiles are reservoirs for S. Pomona, and these cold-blooded animals remain a source of human Salmonella infections. Since the 1980s, this serotype has become a significant public health concern because of the increasing number of cases of S. Pomona infection in humans. To date, outbreaks of Salmonella Pomona infection in humans have mainly occurred in the United States, with some in other countries (e.g. Belgium, Germany, Canada), and most of the infections in humans were associated with turtles and other reptiles. In China, S. Pomona was first isolated from the feces of an infant in Shanghai in 2000, and two further cases of S. Pomona infection in humans were later found in Guangzhou. No one knew the source of S. Pomona in China. In this study, for the first time we isolated S. Pomona from free-living exotic red-eared sliders in the wild in China. Salmonella serotype (. S. Pomona) was isolated from 16 turtle samples. The total carrying rate of S. Pomona in the collected red-eared sliders was 39% (. n=. 41) overall: 40% (. n=. 25) in juveniles and 38% (. n=. 16) in adult turtles. This study suggests that the widespread exotic red-eared sliders may impact on public health and ecosystems of China by transmitting S. Pomona. Additional steps should be considered by the governments and public health agencies to prevent the risk of turtle-associated Salmonella infections in humans in China. © 2013 Elsevier B.V. Source

Zhang Q.,Guangdong Entomological Institute South China Institute of Endangered Animals | Han R.,Guangdong Entomological Institute South China Institute of Endangered Animals | Huang Z.,CAS South China Botanical Garden | Zou F.,Guangdong Entomological Institute South China Institute of Endangered Animals
Biodiversity and Conservation

As forests undergo natural succession following artificial afforestation, their bird assemblages also change. However, interspecific avian social organization associated with forest succession has not been fully understood, particularly for mixed-species bird flocks. To disentangle how mixed-species flocks change as a function of local forest structure, we analyzed flock characteristics (particularly species richness, flocking frequency and propensity) and vegetation physiognomies along a presumed successional series (early, middle, and advanced) simultaneously in subtropical forests in southern China. As hypothesized, monthly point counts demonstrated that complexity of flocks increases with the progression of natural forest succession at a local scale. Advanced forests differed significantly from pioneering plantations with respect to vegetation structure, flock characteristics and constituents (especially for understory specialists). Importantly, forest succession affected flock patterns particularly in relation to the flocking propensity of regular species, and the frequency of nuclear species (Huet's fulvetta Alcippe hueti), which in turn determined flocking occurrence at different successional stands. Canonical correspondence analysis indicated that understory flocking species (mainly Timaliidae babblers) were significantly associated with intact native canopy cover, complex DBH diversity, as well as high densities of dead trees and large trees, representing a maturity level of successional stands. Our study reveals that the effect of natural forest succession on mixed-species bird flocks is species-specific and guild-dependent. From a conservation perspective, despite a high proliferation of pine plantation in southern China, priority should be placed on protecting the advanced forest with a rich collection of understory flocking specialists. © 2013 Springer Science+Business Media Dordrecht. Source

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