Project description:BackgroundThe pangolin is a Pholidota mammal with large keratin scales protecting its skin. Two pangolin species ( Manis pentadactyla and Manis javanica ) have been recorded as critically endangered on the International Union for Conservation of Nature Red List of Threatened Species. Optical mapping constructs high-resolution restriction maps from single DNA molecules for genome analysis at the megabase scale and to assist genome assembly. Here, we constructed restriction maps of M. pentadactyla and M. javanica using optical mapping to assist with genome assembly and analysis of these species.FindingsGenomic DNA was nicked with Nt.BspQI and then labeled using fluorescently labeled bases that were detected by the Irys optical mapping system. In total, 3,313,734 DNA molecules (517.847 Gb) for M. pentadactyla and 3,439,885 DNA molecules (504.743 Gb) for M. javanica were obtained, which corresponded to approximately 178X and 177X genome coverage, respectively. Qualified molecules (≥150 kb with a label density of >6 sites per 100 kb) were analyzed using the de novo assembly program embedded in the IrysView pipeline. We obtained two maps that were 2.91 Gb and 2.85 Gb in size with N50s of 1.88 Mb and 1.97 Mb, respectively.ConclusionsOptical mapping reveals large-scale structural information that is especially important for non-model genomes that lack a good reference. The approach has the potential to guide de novo assembly of genomes sequenced using next-generation sequencing. Our data provide a resource for Manidae genome analysis and references for de novo assembly. This note also provides new insights into Manidae evolutionary analysis at the genome structure level.
Project description:Morphometric relationships and condition factors are crucial to quickly understanding the fitness and well-being of animals. Total length (cm) and bodyweight (g) of 282 (male = 167 and female = 115) pangolins were accounted for in this study which was received and rehabilitated in Pingtung Rescued Center, Pingtung and Endemic Species Research Institute, Nantou, Taiwan. The allometric equation; W = aLb was used to estimate the length-weight relationships where R2 = 0.70, a = 0.61, and b = 1.98. The ratio of total body length and tail length was between 1.1 and 2.7. Pangolins exhibited negative allometric growth (b < 3) as their length increased. The average relative condition factor (KR) was 1.04, indicating a state of good health for rescued individuals. However, Fulton condition factor (KF) and KR fluctuated in different months but was significantly heavier during the wet seasons. This study recommended to release healthy animals with KF of 0.8 or higher back into the wild in order to increase their survival rate. The study, thus will be helpful to promote standardized guidelines for conducting physical measurements and understanding health status. Additionally, it will support the recovery of this threatened species by husbandry and diet management in ex-situ and in-situ conservation.