Small-subunit ribosomal DNA sequencing analysis of dietary shifts during gonad maturation in wild black Amur bream (Megalobrama terminalis) in the lower reaches of the Pearl River

Individual dietary specialization reduces intraspecific competition, rather than feeding activity, in black amur bream (Megalobrama terminalis)

“…Although black amur bream have been an economically important species in the Pearl River basin for many decades, only a handful of studies have explored their feeding ecology 24 , 25 . The goal of the present study was to improve the understanding of intraspecific dietary competition, and its influencing factors, which is important to the protection and sustainable use of black amur bream.…”

“…However, isotope analysis revealed the variation in the contribution of given prey items to the four size groups with results concurring with gut content analysis. The number of prey items determined by isotope analysis was much less than visual, and molecular identification of gut contents 25 . Two isotope ratios powerful evaluated the flow of organic material from three prey items to consumers 33 , but it is hard to determine more than three preys due to the variation in trophic fractionations between preys and consumers [34][35][36] .…”

“…Dietary composition of the black amur bream is supported by a previous study in the Pearl River with a high consumption of detritus 24 . Small subunit ribosomal DNA (18S rDNA) sequenc- www.nature.com/scientificreports/ ing also detected juvenile black amur bream with highly abundant Streptophyta, and adults with more benthic animals 25 . The 18S rDNA sequencing method identified prey items along with intestinal microbes, while gut content identification can more accurately determine the contribution of each item.…”

“…It has been reported that black amur bream mainly consume golden mussel ( Limnoperna fortunei ), Asian clam ( Corbicula fuminea ), organic debris, and aquatic plants 24 . Small subunit ribosomal DNA sequencing analysis revealed that the black amur bream presented dietary shifts during gonad maturation 25 . During the past decade, biomass percentage of black amur bream in catches has decreased by 18.3% 26 , 27 , and the stock status of this species is overexploited 28 .…”

Isolation, identification and character analysis of Streptococcus dysgalactiae from Megalobrama terminalis

“…Megalobrama terminalis (Cypriniformes, Cyprinidae, Culterinae) is mainly distributed in the Pearl River system and other subtropical areas in China, such as Guangdong Province and Hainan Province. M. terminalis is the dominant fish species in the middle and lower reaches of the Pearl River, and its biomass accounts for about 20% of all fish catches (Li et al, ; Shuai et al, ; Xia et al, ). Moreover, M. terminalis has been farmed in large areas in southern China.…”