Reproduction and Development of the Released Przewalski’s Horses (Equus przewalskii) in Xinjiang, China.
- Journal Article
Summary
The study researches the reproductive patterns and development of a group of Przewalski’s horses, released into a protected area in Xinjiang, China. Key findings include a natural birth rate of 38.7%, a foal survival rate of 69.1%, and a significant correlation between environmental factors and reproduction and infant mortality rates.
Reproduction and Development of Przewalski’s Horses
The research focused on the reproduction and development of Przewalski’s horses in a protected area in Xinjiang, China from 2002 to 2006. The highlights of the research include:
- The average reproduction rate among these horses was 38.7%. The lower reproduction rate was primarily due to environmental factors and frequent change of leadership among the stallions. Infertility observed among female horses may be attributed to these reasons.
- The survival rate among foals was 69.1%. This percentage represents the offspring that survived beyond the infant stage.
- Infant mortality rate was 25.0%, of which 83.3% was because of infanticide by the leading stallion.
Seasonal Breeding Patterns
The study also delved into the seasonal breeding patterns among these species. Key findings include:
- Most births occurred in May and June, representing 70.8% of the total offspring born.
- The fertility rates in April and May were 8.3% and 37.5% respectively, lower than the rates observed in captive Przewalski’s horse groups.
- In contrast, the fertility rate in June was higher among the wild group, at 33.3%, than the captive group’s fertility rate of 18.3%.
Environmental Impact on Breeding Patterns
The study established a connection between environmental conditions and breeding patterns. It was found that:
- The peak breeding season for the released group was later than the captive groups, indicating that changes in survival environment and food supplies might influence the breeding cycle.
- The shift in breeding peak could be a result of changes in the surrounding environment and availability of food resources, suggesting that these horses have the ability to adapt their reproductive behaviour according to environmental and resource changes.
Cite This Article
Publication
Researcher Affiliations
- College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, China.
- College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, China ; Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
- Xinjiang Research Center for Breeding Przewalskii Horse, Xinjiang 831700, China.
- College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, China.
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan ; United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.
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Citations
This article has been cited 3 times.- Hu D, Chao Y, Zhang B, Wang C, Qi Y, Ente M, Zhang D, Li K, Mok KM. Effects of Gasterophilus pecorum infestation on the intestinal microbiota of the rewilded Przewalski's horses in China.. PLoS One 2021;16(5):e0251512.
- Tang L, Li Y, Srivathsan A, Gao Y, Li K, Hu D, Zhang D. Gut Microbiomes of Endangered Przewalski's Horse Populations in Short- and Long-Term Captivity: Implication for Species Reintroduction Based on the Soft-Release Strategy.. Front Microbiol 2020;11:363.
- Zhang Y, Cao QS, Rubenstein DI, Zang S, Songer M, Leimgruber P, Chu H, Cao J, Li K, Hu D. Water Use Patterns of Sympatric Przewalski's Horse and Khulan: Interspecific Comparison Reveals Niche Differences.. PLoS One 2015;10(7):e0132094.