Genetic diversity of Chinese alligator (Alligator sinensis) revealed by AFLP analysis: an implication on the management of captive conservation

Abstract

Chinese alligator (Alligator sinensis) is one of the most critically endangered species among 23 extant crocodiles in the world. To prevent the extinction of the species, a captive propagation started at early 1980s, and the total number of alligator was brought up to 10 thousands from dozens of founder in 2000. But several genetic investigations showed those alligators were under an extremely low genetic diversity status with few detectible polymorphic loci. To get more insight into its genetic diversity for the management of captive Chinese alligator, AFLP was adopted to characterize variations in the population. Total of 347 bands were generated from 47 individuals using 3 primer combinations, of which 203 (58.50%) were polymorphic, and 35 AFLP phenotypes were revealed from those individuals. Comparing the results between RAPD and AFLP analysis on almost same sample set clearly indicated that AFLP is more efficient in revealing polymorphic loci, especially in those populations with extremely low genetic diversity. In present three assays, electrophoresis profile also displayed 3 individuals possessing very highly polymorphic AFLP phenotypes that were never been found by RAPD and mtDNA D-loop sequencing, implicating that we should offer these individuals more breeding opportunities to maintain the genetic diversity in the population and restrict those carrying few polymorphic loci from reproduction

Global conservation prioritization areas in three dimensions of crocodilian diversity

“…The species A. sinensis is classified as CR by the IUCN Red List 4 . Because of decreasing of the population of A. sinensis , strategies for the conservation of this species are fundamental, thus some implications for the management of captive breeding have been implemented 46 . However, these individuals in captivity decrease the genetic diversity, resulting in a bottleneck effect 47 .…”

Heterologous microsatellite primers are informative for paca (Cuniculus paca), a large rodent with economic and ecological importance

“…All of the primers (n = 13 or 100%) tested in this study were polymorphic, which permits individuals in a population to be differentiated. It is suspected these primers would be even more informative in a free-ranging paca study, as those populations would likely have higher genetic variability compared to captive populations [ 53 – 55 ]. The low number of founders in the used captive population would suggest it likely possesses some levels of homozygosity (e.g., revealed by monomorphic microsatellites) and low genetic variability [ 56 ].…”

Research Progress of Solar Pond Technology

“…Chengli Ding has studied the concentration distribution, temperature distribution and energy use of glauber solar pond [22]. Chao Wang analyzed the characteristics of the shallow solar pond, a new type of solar collector device, to investigate the feasibility of shallow solar pond as an air source heat pump auxiliary heat sources in winter [23]. Wence Sun carried out the small indoor experiments and tested the temperature, salinity and turbidity distribution of solar pond [24][25][26].…”