Dataset Information

Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis.

ABSTRACT: Identifying how developmental temperature affects the immune system is critical for understanding how ectothermic animals defend against pathogens and their fitness in the changing world. However, reptiles have received little attention regarding this issue. We incubated eggs at three ecologically relevant temperatures to determine how incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis. When exposed to bacterial infections, hatchlings from 24?°C had lower cumulative mortalities (55%, therefore, higher immunocompetence) than those from 28?°C (85%) or 32?°C (100%). Consistent with higher immunocompetence, hatchlings from low incubation temperature had higher IgM, IgD, and CD3? expressions than their counterparts from the other two higher incubation temperatures. Conversely, the activity of immunity-related enzymes did not match the among-temperature difference in immune function. Specifically, enzyme activity was higher at intermediate temperatures (alkaline phosphatase) or was not affected by incubation temperature (acid phosphatase, lysozyme). Our study is the first to provide unequivocal evidence (at the molecular and organismal level) about the significant effect of incubation temperature on offspring immunity in reptiles. Our results also indicate that the reduced immunity induced by high developmental temperatures might increase the vulnerability of reptiles to the outbreak of diseases under global warming scenarios.

SUBMITTER: Dang W

PROVIDER: S-EPMC4450580 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis.

Dang Wei W Zhang Wen W Du Wei-Guo WG

Scientific reports 20150601

Identifying how developmental temperature affects the immune system is critical for understanding how ectothermic animals defend against pathogens and their fitness in the changing world. However, reptiles have received little attention regarding this issue. We incubated eggs at three ecologically relevant temperatures to determine how incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis. When exposed to bacterial infections, hatchlings from 2 ...[more]

PMID: 26028216

Similar Datasets

Project description:BackgroundChinese soft-shell turtle (Pelodiscus sinensis) is an important commercial species for their high nutritional value and unique taste, but it has been a vulnerable species due to habitat loss. In this study, homologous juvenile turtles were allocated to lake, pond and paddy field to investigate the habitat effects on turtles.ResultsThe growth, morphology and gut microbial communities were monitored during the 4 months cultural period. It showed higher growth rate of turtles in paddy field and pond. The appearance, visceral coefficients, gut morphology and microbial communities in turtles were distinct among different habitats. The microbial community richness on Chao1 was obviously lower in initial turtle guts from greenhouses, whereas it was relative higher in turtle guts sampled from paddy fields than ponds and lake. Significant differences on dominant microbes were found among initial and subsequent samples from different habitats. Firmicutes was the most abundant phylum in the guts of turtles sampled from the greenhouse initially, while Proteobacteria was the most abundant phylum after cultivation in different habitats, followed by Bacteroidetes. The microbial composition were distinct in different habitats at 60d, and the appearance of dominant phyla and genera was more driven by sampling time than habitats at 120d. Both the sampling time and habitats affected the appearance of dominant phyla and genera during the cultivation. The functional predictions indicated that both habitat type and sampling time had significant effects on metabolic pathways, especially amino acid and carbohydrate metabolism.ConclusionsThe turtles could adapt to natural lakes, artificial ponds and paddy fields. The gut microbial abundance was different among the habitats and sampling time. The species of microbes were significantly more diverse in paddy field specimens than in those from ponds and lakes. Rice-turtle coculture is a potential ecological and economic farming mode that plays important roles in wild turtle protection and food security.

Project description:The Chinese soft-shelled (Pelodiscus sinensis) turtle exhibits obvious sex dimorphism, which leads to the higher economic and nutritional value of male individuals. Exogenous hormones can cause the transformation from male to female phenotype during gonadal differentiation. However, the molecular mechanism related to the sexual reversal process is unclear. In this study, we compared the difference between the small RNAs of male, female, and pseudo-female turtles by small RNA-seq to understand the sexual reversal process of Chinese soft-shelled turtles. A certain dose of estrogen can cause the transformation of Chinese soft-shelled turtles from male to female, which are called pseudo-female individuals. The result of small RNA-seq has revealed that the characteristics of pseudo-females are very similar to females, but are strikingly different from males. The number of the microRNAs (miRNAs) of male individuals was significantly less than the number of female individuals or pseudo-female individuals, while the expression level of miRNAs of male individuals were significantly higher than the other two types. Furthermore, we found 533 differentially expressed miRNAs, including 173 up-regulated miRNAs and 360 down-regulated miRNAs, in the process of transformation from male to female phenotype. Cluster analysis of the total 602 differential miRNAs among females, males, and pseudo-females showed that miRNAs played a crucial role during the sexual differentiation. Among these differential miRNAs, we found 12 miRNAs related to gonadal development and verified their expression by qPCR. The TR-qPCR results confirmed the differential expression of 6 of the 12 miRNAs: miR-26a-5p, miR-212-5p, miR-202-5p, miR-301a, miR-181b-3p and miR-96-5p were involved in sexual reversal process, which was consistent with the results of omics. Using these six miRNAs and some of their target genes, we constructed a network diagram related to gonadal development. We suggest that these miRNAs may play an important role in the process of effective sex reversal, which would contribute to the breeding of all male strains of Chinese soft-shelled turtles.

Project description:Vibrio cholerae is an important human pathogen and environmental microflora species that can both propagate in the human intestine and proliferate in zooplankton and aquatic organisms. Cholera is transmitted through food and water. In recent years, outbreaks caused by V. cholerae-contaminated soft-shelled turtles, contaminated mainly with toxigenic serogroup O139, have been frequently reported, posing a new foodborne disease public health problem. In this study, the colonization by toxigenic V. cholerae on the body surfaces and intestines of soft-shelled turtles was explored. Preferred colonization sites on the turtle body surfaces, mainly the carapace and calipash of the dorsal side, were observed for the O139 and O1 strains. Intestinal colonization was also found. The colonization factors of V. cholerae played different roles in the colonization of the soft-shelled turtle's body surface and intestine. Mannose-sensitive hemagglutinin (MSHA) of V. cholerae was necessary for body surface colonization, but no roles were found for toxin-coregulated pili (TCP) or N-acetylglucosamine-binding protein A (GBPA). Both TCP and GBPA play important roles for colonization in the intestine, whereas the deletion of MSHA revealed only a minor colonization-promoting role for this factor. Our study demonstrated that V. cholerae can colonize the surfaces and the intestines of soft-shelled turtles and indicated that the soft-shelled turtles played a role in the transmission of cholera. In addition, this study showed that the soft-shelled turtle has potential value as an animal model in studies of the colonization and environmental adaption mechanisms of V. cholerae in aquatic organisms.IMPORTANCE Cholera is transmitted through water and food. Soft-shelled turtles contaminated with Vibrio cholerae (commonly the serogroup O139 strains) have caused many foodborne infections and outbreaks in recent years, and they have become a foodborne disease problem. Except for epidemiological investigations, no experimental studies have demonstrated the colonization by V. cholerae on soft-shelled turtles. The present studies will benefit our understanding of the interaction between V. cholerae and the soft-shelled turtle. We demonstrated the colonization by V. cholerae on the soft-shelled turtle's body surface and in the intestine and revealed the different roles of major V. cholerae factors for colonization on the body surface and in the intestine. Our work provides experimental evidence for the role of soft-shelled turtles in cholera transmission. In addition, this study also shows the possibility for the soft-shelled turtle to serve as a new animal model for studying the interaction between V. cholerae and aquatic hosts.

Project description:Background:As the primary source of protein for aquaculture, fishmeal has reached the extremity of sustainable development, our previous studies have proven that rice protein concentrate and squid paste are outstanding protein source and stimulant for Pelodiscus sinensis. However, little attention has been given to the molecular mechanism of the appetite modulated by the dietary nutrient factor, especially for a reptile. Thus, the present study aimed to evaluate feed intake and brain-gut dynamic responses to dietary rice protein concentrate and squid paste in Chinese soft-shelled turtle Pelodiscus sinensis. Methods:Three isonitrogenous and isoenergetic practical diets were formulated including 60% fishmeal (CT), 42% fishmeal + 18% rice protein concentrate (RP) and 42% fishmeal + 18% rice protein concentrate + 1% squid paste (RPS), respectively. Microcapsule lysine was supplemented in RP and RPS diets to balance the amino acid profile. Turtles (initial weight 30.65 ± 0.97 g) were fed three times daily to apparent satiation. After the 8-week feeding trial, the turtles were exposed to 48h food deprivation, then the dynamic expression of the orexigenic and anorexigenic peptides were measured. Results:The results showed that no significant effect was observed on feed intake when fishmeal was replaced by rice protein concentrate (P = 0.421), while significantly improved feed intake was found by squid paste supplemented (P = 0.02). The mRNA expression of anorexigenic peptides, such as leptin receptor, insulin receptor, pro-opiomelanocortin, cocaine and amphetamine-regulated transcript, cholecystokinin (and its receptor) and glucagon-like peptide-1 receptor in the brain increased significantly at 3 h past feeding (P < 0.05), and then decreased. Nevertheless, neuropeptide Y and peptide YY mRNA expression showed the valley at 3h and peak at 12h past feeding. Intestinal cholecystokinin receptor and glucagon-like peptide-1 receptor mRNA expression showed no difference during the postprandial time (P > 0.05). The results suggested that squid paste is an outstanding stimulant for Pelodiscus sinensis. Furthermore, the orexigenic and anorexigenic peptides evaluated here might play an essential role in short-term fasting to this species, of which the dynamic expression levels were regulated by squid paste.

Dataset Information

Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis.

Publications

Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets