AUTHOR=Mao Yifan , Lv Weiwei , Huang Weiwei , Yuan Quan , Yang Hang , Zhou Wenzong , Li Mingyou 

TITLE=Effects on growth performance and immunity of Monopterus albus after high temperature stress

JOURNAL=Frontiers in Physiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2024.1397818

DOI=10.3389/fphys.2024.1397818

ISSN=1664-042X

ABSTRACT=<p>To investigate the impact of the effect of high temperature stimulation on <italic>Monopterus albus</italic> larvae after a certain period of time, five experimental groups were established at different temperatures. Then, the <italic>M. albus</italic> under high temperature stress was fed at 30°C for 70 days. After that, the growth index of the <italic>M. albus</italic> was counted and analyzed. In terms of growth index, high temperature stress had significant effects on FCR, FBW, WGR, and SGR of <italic>M. albus</italic> (<italic>p &lt;</italic> 0.05). The SR increased after being stimulated by temperature (<italic>p &lt;</italic> 0.1). The study revealed that liver cells of <italic>M. albus</italic> were harmed by elevated temperatures of 36°C and 38°C. In the experimental group, the activities of digestive enzymes changed in the same trend, reaching the highest point in the 32°C group and then decreasing, and the AMS activity in the 38°C group was significantly different from that in the 30°C group (<italic>p</italic> &lt; 0.05). The activities of antioxidase in liver reached the highest at 34°C, which was significantly different from those at 30°C (<italic>p</italic> &lt; 0.05). In addition, the expression levels of <italic>TLR1</italic>, <italic>C3</italic>, <italic>TNF-α</italic>, and other genes increased in the experimental group, reaching the highest point at 34°C, and the expression level of the <italic>IL-1β</italic> gene reached the highest point at 32°C, which was significantly different from that at 30°C (<italic>p</italic> &lt; 0.05). However, the expression level of the <italic>IRAK3</italic> gene decreased in the experimental group and reached its lowest point at 34°C (<italic>p</italic> &lt; 0.05). The expression level of the <italic>HSP90α</italic> gene increased with the highest temperature stimulus and reached its highest point at 38°C (<italic>p</italic> &lt; 0.05). In the α diversity index of intestinal microorganisms in the experimental group, the observed species, Shannon, and Chao1 indexes in the 34°C group were the highest (<italic>p</italic> &lt; 0.05), and β diversity analysis revealed that the intestinal microbial community in the experimental group was separated after high temperature stimulation. At the phylum level, the three dominant flora are <italic>Proteus</italic>, <italic>Firmicutes</italic>, and <italic>Bacteroides</italic>. <italic>Bacteroides</italic> and <italic>Macrococcus</italic> abundance increased at the genus level, but <italic>Vibrio</italic> and <italic>Aeromonas</italic> abundance decreased. To sum up, appropriate high-temperature stress can enhance the immunity and adaptability of <italic>M. albus</italic>. These results show that the high temperature stimulation of 32°C–34°C is beneficial to the industrial culture of <italic>M. albus</italic>.</p>