Riverbed Substrate Requirements for Natural Reproduction of Gymnocypris przewalskii

Gymnocypris przewalskii (i.e., Qinghai Lake naked carp) is a migratory fish species that lives in highland brackish water. It is important to understand the abiotic environment required by this fish to reproduce naturally so that its habitat can be protected and the wild population can be conserved. Here, artificial simulation and spawning ground substrate transformation experiments were conducted to examine the riverbed substrate requirements for G. przewalskii to naturally reproduce. Using various techniques (in vitro markers, videography, and Ethovision XT behavior tracking), this study systematically investigated the riverbed substrate preferences of G. przewalskii as well as the characteristics and effectiveness of natural reproduction induced by pebble riverbed substrate. The findings can be summarized as follows: (1) the habitat preferences of G. przewalskii differed significantly between various riverbed substrate, with pebble substrate being preferred during natural reproduction, and sand substrate being preferred pre- and post-spawning, and (2) the natural reproduction of G. przewalskii was heavily reliant on pebble riverbed substrate. Specifically, pebble substrate significantly improved spawn quantity and fertilization rate. These findings provide scientific evidence for the improvement and restoration of G. przewalskii spawning grounds, and insights regarding the artificial bionic reproduction of G. przewalskii.

Disordered Climate Threatens Short-Distance Migrants

In the global warming world, the migratory and breeding behaviors of many species have changed, and short-distance migrants may benefit from climate change. With climate change leading to an increasingly disordered climate, we show here that a disordered spring climate disturbs the migration and breeding of a short-distance anadromous fish. In 2020, on the Qinghai-Tibetan Plateau, an abnormally low temperature in April delayed the migration rhythm of Gymnocypris przewalskii by nearly 10 days, while the gonadal development rhythm of the breeding population was almost normal. The phenology mismatch decreased the migrating populations by 30–70%, reducing the larval flux by nearly 80%. This case reveals that for short-distance migrants, different phenologies within the same species respond to disordered climates differently, which leads to phenology mismatches and then threatens the species. Along with increasing local abnormal climate events, short-distance migrants need more attention and conservation actions.

Disordered climate threatens short-distance migrants

Global climate change has led to a warmer world, changing the migratory and breeding behaviors of many species, and short-distance migrants may benefit from climate change. With climate change leading to an increasingly disordered climate, we show here that a disordered spring climate disturbs the migration and breeding of a short-distance anadromous fish. In 2020, on the Qinghai-Tibetan Plateau, an abnormally low temperature in April delayed the migration rhythm of Gymnocypris przewalskii by nearly 10 days, while the gonadal development rhythm of the breeding population was almost normal. The phenology mismatch decreased the migrating populations by 30% - 70%, reducing the larval flux by nearly 80%. This case reveals that for short-distance migrants, different phenologies within the same species respond to disordered climates differently, which leads to phenology mismatches and then threatens the species. Along with increasing local extreme weather and climate events, short-distance migrants need more attention and conservation actions.

16S rRNA Gene Amplicon Sequencing of Gut Microbiota from Naked Carp (Gymnocypris przewalskii) in Qinghai Lake, China

Naked carp ( Gymnocypris przewalskii ) is a second-grade animal under state protection of China. We report 16S rRNA gene amplicon analysis of the gut microbiota of Gymnocypris przewalskii . The three most abundant phyla are Tenericutes , Proteobacteria , and Fusobacteria , and the six most abundant genera are Aeromonas , Clostridium , Cetobacterium , Shewanella , Prochlorococcus , and Vibrio .

Isolation, identification and 16S rRNA gene analysis of Yersinia enterocolitica strains isolated from the Gymnocypris Przewalskii

Background: Yersinia enterocolitica is a human-animal-fish-associated infectious diarrhea pathogen that has caused widespread international attention in recent years. Many strains of Yersinia enterocolitica were identified from different animal species, but there is no information reported Yersinia enterocolitica in Gymnocypris przewalskii . The Gymnocypris przewalskii is a very important species in the Qinghai Lake. They were listed in the China' s second-class protected animal species. Preliminary research on the distribution of Yersinia enterocolitica and the drug sensitive fauna test on Gymnocypris przewalskii was a urgent solving problem for which maintain the original ecological symbiotic system and restore Gymnocypris przewalskii resource. In order to solve these issues, we performed this research.Results: The results showed that 5 strains Yersinia enterocolitica were obtained, positive ratio was 6.67% (5/75). The average drug-resistant of 5 strain Yersinia enterocolitica was 54.29% (38/70) to 14 kinds of antibiotic. The result of 16S rRNA gene of Yersinia enterocolitica identified showed that one piece of 1419 bp specific braid was obtained. The homologies of nucleotide of 16S rRNA were 91%-95% between 15 strains of Yersinia enterocolitica from GenBank by measuring sequence.Conclusion: Yersinia enterocolitica can infect Gymnocypris przewalskii . Some strains have drug-resistant effect. The 16S rRNA gene matches 91%-95% with other strains nucleotides download from GenBank and forms a unique branch separated from them.

Isolation, identification and 16S rRNA gene analysis of Yersinia enterocolitica strains isolated from the Gymnocypris przewalskii

Background: Yersinia enterocolitica is a human-animal-fish-associated infectious diarrhea pathogen that has caused widespread international attention in recent years. Many strains of Yersinia enterocolitica were identified from different animal species, but there is no information reported Yersinia enterocolitica in Gymnocypris przewalskii. The Gymnocypris przewalskii is a very important species in the Qinghai Lake. They were listed in the China' s second-class protected animal species. Preliminary research on the distribution of Yersinia enterocolitica and the drug sensitive fauna test on Gymnocypris przewalskii was a urgent solving problem for which maintain the original ecological symbiotic system and restore Gymnocypris przewalskii resource. In order to solve these issues, we performed this research.Methods: Pathogen of Yersinia enterocolitica of 75 death Gymnocypris przewalskii was isolated by routine isolation culture and identification technique in fishing bank of Xining. At the same time, the drug sensitive fauna test had been detected. At the meantime, 16S rRNA gene of Yersinia enterocolitica was cloned and sequences identified.Results: The results showed that 5 strains Yersinia enterocolitica were obtained, positive ratio was 6.67% (5/75). 1 strains bacteria had lethal effect to mice by pathogenic test. The average drug-resistant of 5 strain Yersinia enterocolitica was 54.29% (38/70) to 14 kinds of antibiotic. The result of 16S rRNA gene of Yersinia enterocolitica identified showed that one piece of 1419 bp specific braid was obtained. The homologies of nucleotide of 16S rRNA were 91%-95% between 15 strains of Yersinia enterocolitica from GenBank by measuring sequence.Conclusion: Yersinia enterocolitica can infect Gymnocypris przewalskii. Some strains cause lethal effect to mice and have drug-resistant effect. The 16S rRNA gene matches 91%-95% with other strains nucleotides download from GenBank and forms a unique branch separated from them.Trial registration: During this research, we didn’t need to apply for trail and have no trial registration number.