Page 132 - 《水产学报》2025年第12期

邹奥锟，等 水产学报, 2025, 49(12): 129610

Growth, carbon and nitrogen balances, and transcriptome analysis of
the allometric growth in Symphysodon haraldi

1,2
1,2
1,2*
ZOU Aokun , GAO Jianzhong , WEN Bin , CHEN Zaizhong 1,2*
1. Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture and Rural Affairs,
Shanghai Ocean University, Shanghai 201306, China;
2. Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education,
Shanghai Ocean University, Shanghai 201306, China

Abstract: To explore the potential process of growth heterogeneity in discus fish, this experiment selected five pairs of the
same species of discus fish as parents and cultivated their offspring for 60 days. The offspring were divided into two extreme
groups with significant differences in body weight: the slow-growing group (S group) with the weight of (0.153±0.011) g and
the fast-growing group (F group) with the weight of (0.347±0.030) g. After 30 days of cultivation, the growth, nutrient diges-
tion, carbon and nitrogen balance, and transcriptome analysis of the visceral tissue of the discus fish were measured. The res-
ults showed that, in terms of growth, the average daily weight gain, average daily feed intake and feed efficiency of the F group
were significantly higher than those of the S group. In terms of digestion, the apparent digestibility of dry matter, carbon, and
nitrogen in the F group was significantly higher than those in the S group; the activities of α-amylase and gastric protease in the
viscera of the F group were significantly higher than those in the S group. In terms of carbon and nitrogen balance, the F group
absorbed more carbon and nitrogen, mainly for growth, and excreted less carbon and nitrogen through feces and
respiration/excretion than the S group. Transcriptome analysis showed that the differentially expressed genes between the two
groups were mainly enriched in signal pathways such as myocardial contraction, calcium signaling, glycolysis/gluconeogenesis,
PPAR, thyroid hormone, purine metabolism, insulin secretion, galactose metabolism, and the pentose phosphate pathway.
Among them, the significantly upregulated genes in the F group included ann, mid1, pur, fat, elo, acy, and dcK, and both the
PPAR signaling pathway and purine metabolism may be related to the rapid growth of the F group. The results indicate that
compared to the small-sized discus fish, the large-sized individuals have stronger growth and digestion abilities and higher util-
ization of carbon and nitrogen, which may be related to the activation of the PPAR signaling pathway and purine metabolism,
providing a theoretical basis for the nutritional intervention and breeding of allometric growth fish.
Key words: Symphysodon haraldi; allometric growth; digestion; carbon and nitrogen balances; transcriptome

Corresponding authors: WEN Bin. E-mail: bwen@shou.edu.cn;
CHEN Zaizhong. E-mail: chenzz@shou.edu.cn
Funding projects: Shanghai Natural Science Foundation (20ZR1423600); Shanghai Sailing Program (19YF1419400)

中国水产学会主办 sponsored by China Society of Fisheries https://www.china-fishery.cn
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