Division of Chinese soft‐shelled turtle intestine with molecular markers is slightly different from the morphological and histological observation

Abstract

The Chinese soft-shelled turtle (Pelodiscus sinensis) is a commercially important species in Asian countries. Knowledge of its nutritional requirements and physiology is essential for determining the appropriate content of the feed for this animal. However, the lack of functional characterization of the intestine of this turtle limits the understanding of its absorption and utilization of nutritional materials. To solve this problem, this work utilized anatomical and histological methods to characterize 9 segments sampled along the anterior-posterior axis of the intestine. Furthermore, 9 genes, which have been well documented in the intestine division of mammals and fish, were employed to functionally characterize the 9 sampled segments. Our results suggest that regions covering from the starting site to S3 (position at 29.9% of the total length from the starting of the intestine) are the equivalent of mammalian dedumonen, and those covering S4 (40.2%) and S5 (65.4%), posterior to S8 (92.7%), are the equivalent of the mammalian ileum and the large intestine, respectively. As to the region spaning S6 (81.3%) and S7 (87.3%), its functional equivalent (small intestine or large intestine) may be variable and depends on the functional genes. This molecular characterization in relation to the division of the intestine of Chinese soft-shelled turtle may contribute to the understanding of the nutritional physiology of the turtle, and promote Chinese soft-shelled turtle production.

A New IL6 Isoform in Chinese Soft-Shelled Turtle (Pelodiscus sinesis) Discovered: Its Regulation during Cold Stress and Infection

“…This implied that the two cDNA were more likely splice variants rather than transcripts from two different paralogs. Several other findings gave support to our conclusion: (1) At present, no duplicated IL6 genes have ever been found in vertebrates ranging from teleost to mammals [2][3][4][5][6][7][8][9][10][11][12]14]; (2) Duplicated genes are less likely to share the same 3 UTRs [29];…”

Effects of Dietary Phosphorus Levels on Growth Performance, Phosphorus Utilization and Intestinal Calcium and Phosphorus Transport-Related Genes Expression of Juvenile Chinese Soft-Shelled Turtle (Pelodiscus sinensis)

“…After that, the turtles were dissected on chilled trays, the small intestine and liver were collected, frozen in the liquid nitrogen and stored at −80 °C for gene expression analyses. The small intestine was differentiated from the large intestine according to the previous study [ 46 ].…”

Direct Full-Length RNA Sequencing Reveals an Important Role of Epigenetics During Sexual Reversal in Chinese Soft-Shelled Turtle

“…In recent years, the new aquatic species of yellow catfish, Japanese flounder and tilapia were successfully bred based on gender dimorphism (Palaiokostas et al, 2015;Zhang et al, 2016). Chinese soft-shelled turtle is another economically important aquatic animal that displays a high degree of gender dimorphism (Zhang et al, 2018). Despite years of study, our understanding of the biological basis of sexual dimorphism of Chinese soft-shelled turtle remains incomplete.…”