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月刊，1984年创刊
主管：内蒙古自治区教育厅
主办：包头医学院
主编：赵云山
特邀主编：高长青
编辑出版：包头医学院学报编辑部
国际刊号：ISSN 1006－740X
国内刊号：CN 15－1182/R
邮发代号：16-292

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2025 Vol. 44, No. 2 Published: 2025-03-25

Research and Application Overview and Specific Topic

Research and Application

	171	Effects of Activation of Mitophagy on Adipocyte Apoptosis and Growth and Development in Grass Carp Ctenopharyngodon idella
		ZENG Caihong, BIAN Chenchen, SUN Jian, JI Hong, LI Handong, HU Zechao
		DOI: 10.16378/j.cnki.1003-1111.24022
		Excessive lipid deposition in grass carp Ctenopharyngodon idella adipose tissue as one of the common and prominent problems in aquaculture production can be dealt with induction of adipocyte apoptosis.To investigate the relationship between mitophagy and apoptosis in grass carp adipocytes, 2 trails were designed and conducted in vitro and in vivo. In vitro, juvenile grass carp with body weight of some 20 g were reared in net cages and fed diets containing 0 mg/kg (control group), 10 mg/kg, 20 mg/kg, and 40 mg/kg mitophagy activatorcarbonyl cyanide-3-chlorophenylhydrazone (CCCP) at water temperature of 24—30 ℃for 8 weeks. In vitro trail, the isolated primary adipocytes of grass carpwere cultured, differentiated and matured, and then treated with CCCP at dose of 0(control group), and 20 μmol/L for 24 h.The results in the vivo assay showed that compared with the control group, the treatment of 40 mg/kg of mitophagy activator led to significantly lower grass carp intraperitoneal fat index (P<0.05), and the content of triglycerides (P<0.05), and to significantly elevated the mRNA levels of autophagy-related genes pink1, parkin, atg12, atg5 and apoptosis-related genes caspase3 and caspase9 (P<0.05), without significant change in the size of adipocyte area in each treatment group compared with the control group (P>0.05). In vivo results showed that there were significantly elevated cellular mitophagy-related genes pink1, parkin, atg4, atg7, and atg12(P<0.01), significant increase in the mRNA levels of the apoptosis-related genes bax, caspase9, and the bax/bcl-2 ratio (P<0.05 or P<0.01), and significant decrease in the mRNA of the anti-apoptosis gene bcl-2level (P<0.05), and cellular triglyceride content (P<0.05) in the fish fed the diet containing the activator. It was found that mitophagy activator treatment activated mitophagy and apoptosis. The findings indicate that reduction of intraperitoneal fat index in grass carp may be realized by inducing apoptosis of grass carp adipocytes, thus reducing lipid accumulation in grass carp. Combined in vivo and in vitro assays showed that mitophagy activator treatment activated mitophagy mediated by Pink1/Parkin.
		2025 Vol. 44 (2): 171-180 [Abstract] ( 194 ) HTML (1 KB) PDF (3541 KB) ( 40 )

	181	Species Composition and Diversity of Crustacean Community in the Waters Adjacent to Changshan Islands
		CAO Jingxuan, ZOU Jianyu, XU Binduo, SUN Lidong, JI Yupeng
		DOI: 10.16378/j.cnki.1003-1111.24027
		In order to ascertain the species composition and diversity of crustacean community in the adjacent waters of Changshan Islands, the seasonal and spatial changes in crustacean species composition, dominant species, community species diversity and their correlations with environmental factors were analyzed by ecological diversity index and index of relative importance (IRI) and generalized additive model based on the seasonal survey data of fishery resources and marine environment in the adjacent waters of Changshan Islands in autumn in 2016, and winter, spring and summer in 2017. There were 37 species captured, 2 orders, 16 families and 26 genera, with 18.92% of warm water species, 72.97% of warm temperate species and 8.11% of cold temperate species in the total number of crustacean species. The crustacean resources density was shown to be obvious spatial and seasonal changes in the adjacent waters of Changshan Islands, with species composition replacement rates ranging from 36% to 53%, higher replacement rates in autumn-winter (53%) and in winter-spring (48%), and lower replacement rate in spring-summer (37%) and summer-autumn (36%). Mantis shrimp Oratosquilla oratoria was found to be the dominant species in each season, and Crangon affinis and Alpheus japonicas to be the common dominant species in spring and winter. Higher species diversity index (D) of crustacean community was observed in spring and summer (2.22), and lower in winter (1.66), and higher Shannon-Wiener diversity index (H') and evenness index (J') in autumn (1.48) and low in summer (0.26). There were significant spatial changes in species diversity index in crustaceans, with the peak species richness index (D) in the northwest of the surveyed area in spring, with low value in the southeast sea and near the coast, two peaks in the central sea area in summer, and high value in the southwest and low value in the northeast in autumn. There were two peaks of Shannon-Wiener's Diversity Index (H') in the northwest and southeast seas in autumn, and a peak in the northeast in winter, with a lower value near the coast. The peak evenness index (J') was observed in the southeast coast in autumn. Generalized additive model (GAM) analysis revealed that water depth, bottom temperature and bottom salinity were the environmental factors affecting the spatial distribution of crustacean diversity in this sea area. The findings indicate that the species composition and diversity of crustaceans have obvious spatial and temporal heterogeneity in the adjacent waters of Changshan Islands.
		2025 Vol. 44 (2): 181-190 [Abstract] ( 122 ) HTML (1 KB) PDF (4988 KB) ( 86 )

	191	*Predation on Gray Planthopper Laodelphax striatellus* by Chinese Mitten Crab Eriocheir sinensis in Rice-Crab Co-Culture**
		WANG Yuquan, FAN Sining, YU Yilin, MEI Jie, SUN Na, LIANG Xiaochen, LIU Xueshen, LI Xiaodong
		DOI: 10.16378/j.cnki.1003-1111.21187
		In order to explore the predation of gray planthopper Laodelphax striatellus by Chinese mitten crab Eriocheir sinensis in rice-crab co-culture, field trial and laboratory test were carried out in Panjin Guanghe Crab Industry Co., Ltd., in Dawa District, Panjin City, Liaoning Province, from June 10 to September 24, 2020. The changes in the number of gray planthoppers were measured in the field by a pot shooting method, the gastrointestinal food contents were analyzed in the Chinese mitten crab in the field, and effects of Chinese mitten crab with body weight of 12-24 g, as well as the female crabs with body weight of (20±4) g and (10±2) g, sex, and short-term starvation on the predation function of the Chinese mitten crab on the gray planthopper were simulated in a laboratory to probe the predation mechanism of the Chinese mitten crab with body weight of 12—24 g on the gray planthopper in the field. The results showed that there was decrease in number of gray planthopper by 53.05% in field trial and 51.5% in laboratory test compared with that in the field without Chinese mitten crab, with significantly more gray planthopper in the field with large Chinese mitten crab than in the field with small Chinese mitten crab higher than that in the filed with small ones (P<0.01). The Chinese mitten crab exposed to short-term starvation had significantly higher feeding ability of gray planthopper than that in the satiety group (P<0.01), without significant difference in the feeding ability between male and female individuals. Therefore, the increase in body weight and short-term starvation can lead to significantly enhance the ability of Chinese mitten crab to prey on gray planthoppers, and the three predatory functional response models are in line with the Holling Ⅱ equation.
		2025 Vol. 44 (2): 191-201 [Abstract] ( 87 ) HTML (1 KB) PDF (1592 KB) ( 26 )

	202	*Evaluation of Heterosis of Growth and Photosynthetic Efficiency in Hybrid Offsprings from Multiple Crosses between Northern and Southern Kelp Laminaria japonica* Cultivars in China**
		SONG Guiwen, HUANG Xiang, ZHANG Di, YAN Yu, JIN Haiping, XU Yuanyuan, DAI Hongliang, LIU Fuli
		DOI: 10.16378/j.cnki.1003-1111.24018
		The female and male gametophytes of kelp Laminaria japonica Lianza 1 and Haijia 1 in the southern seas, 901, Yudai 1 and Dongfang 7 in the northern seas were cultured in solutions with final concentrations of 4 mg/L N and 0.4 mg/L P in sterilized seawater at 1600 lx (16L∶8D) and 10 ℃, and the gametophyte cloning and multiplication and self-breeding of various varieties were carried out by shaking culture. By comparing the growth rate and anti-high-light ability of the hybrid offspring, the heterosis characteristics of cross-breeding with different parental combinations were evaluated, and the mechanism of heterosis formation of high-light tolerance of kelp was probed by photosynthetic physiology to provide a basis for the breeding of high light-resistant varieties. The results showed that significant high-parent heterosis was observed in only a few crossing combinations, with mid-parent heterosis in most hybrid offsprings, indicating that crossing did not necessarily produce heterosis in growth and stress resistance. The 5—10 cm length seedlings had the maximum growth light intensity of 13 600 lx, and crossing and reciprocal crossing had a significant impact on the growth rate and high light resistance of hybrid offspring. The growth rate and high light resistance of offspring were shown to be more similar to their female parent self-cross group. The findings provide new ideas and evidence for cross breeding of kelp to cultivate high light-resistant varieties.
		2025 Vol. 44 (2): 202-211 [Abstract] ( 68 ) HTML (1 KB) PDF (2439 KB) ( 11 )

	212	Observation of Larval Development and Determination of Point of No Return of Barbatula nuda
		WU Chen, LUO Xiaonian, DUAN Youjian, LI Jiao, XING Yuxin, JI Chenyue, LI Quansen
		DOI: 10.16378/j.cnki.1003-1111.23097
		In order to explore the developmental characteristics and optimal feeding time of larval Barbatula nuda, the microscopic morphological observation of B. nuda larvae and juvenile was carried out systematically from 0 to 44 days post hatching(dph) and effects of fasting on larval development, growth and digestive tract and the point of no return (PNR) were investigated. The results showed that the early development stage of B. nuda was divided into yolk sac larvae stage (0—4 dph), late larvae stage (5—26 dph) and juvenile stage(27—44 dph) at water temperature of 16.2—20.0℃ according to the exhaustion of yolk sac, formation of air bladder and body color. The newly hatched larvae had total length of (4.09±0.11) mm, and the yolk sac volume of (0.1176±0.0304) mm³. The initial feeding was observed in the larvae at 3 dph, and the yolk sac was completely exhausted at 5 dph, with mixed trophic of 3 days. At 27 dph, the air bladder drum can be observed clearly, and the end of notochord began to bend, signing the juvenile stage. The B. nuda had similar morphology of juvenile to that of adult at 44 dph. The result of starvation test showed that the initial feeding rate of the starvation larvae was 35%, with the maximum food ingestion rate of 90% for 2 days. Compared with feeding groups, the starvation larvae showed decrease in vitality, weakened clustering, and solitary swimming, without intestinal folds formed. The activities of pepsin and trysin were (0.54±0.07) U/mL and (58.83±13.99) U/mL in the starvation groups, respectively, significantly lower than those in the feeding groups (P<0.01). The degrowth was observed in the starved larvae at 6 dph, with a large number larvae starting to be death at 7 dph and all dead at 10 dph. It was found that the point of no return was 7—8 dph. Therefore, the optimal initial feeding may be 3—4 dph for B. nuda larvae. The findings preliminarily revealed the basic rules of early development of B. nuda and provided basic biological data for the early development biology research and feeding strategies of B. nuda.
		2025 Vol. 44 (2): 212-222 [Abstract] ( 74 ) HTML (1 KB) PDF (7136 KB) ( 13 )

	223	Effects of Two Species of Green Microalgae on Water Quality and Biofilm Flora Structure in Aquaculture Systems of Pacific White Shrimp Litopenaeus vannamei
		LYU Libin, LIU Chao, SUN Mingzhu, XU Ailing, SONG Zhiwen
		DOI: 10.16378/j.cnki.1003-1111.24037
		In order to investigate the effects of addition of green algae Chlorella pyrenoidosa and Haematococcus pluvialis on water quality, growth, biofilm bacterial community structure, and diversity of the Pacific white shrimp Litopenaeus vannamei in an internal circulation aquaculture system, a hydrophilic polyurethane gel filler with hanging film was loaded into a mesh bag, placed in an 80 L glass tank at 5% (V/V), with a salinity of 15 artificial seawater, and 64 juvenile shrimp (800 individuals/m³) with body length of (0.8±0.1) cm were stocked, and reared for 84 d and 10 mL of C. pyrenoidosa and H. pluvialis were added every 3 days, respectively, and no algae were added to the control group at water temperature of 26—28 ℃. Wash the hydrophilic polyurethane gel filler every 7 days and replenish it regularly. The results showed that the addition of microalgae led to reduce contents of nitrate nitrogen (NO^-₃-N) and total phosphorus (TP) in the aquaculture system, with decrease in NO_3--N and TP by 13.0% and 17.7% in C. pyrenoidosa group and 6.3% and 29.7% H. pluvialis group. However, there were variations in ammonia nitrogen (TAN)and nitrite nitrogen (NO^-₂-N) performance: decrease in concentration in H. pluvialis group and increase in C. pyrenoidosa group in the aquaculture system. The body length, body weight, average daily growth rate (ADG), and feed utilization efficiency were improved in the shrimp exposed to addition of microalgae, without significant effect on shrimp survival rate. Body weight was found to be increased in the shrimp by 15.0% in C. pyrenoidosa group and 11.8% in H. pluvialis group.Analysis of bacterial community structure and diversity revealed that the relative abundances of Proteobacteria and Bacteroidetes were decreased in C. pyrenoidosa system and the relative abundance of Acidobacteria was increased; relative abundance of Bacteroidetes was increased in H. pluvialis system while Acidobacteria and Proteobacteria were decreased instead. Additionally, the relative abundance of nitrifying bacteria was shown to be increased in the added microalgae culture systems, while the relative abundance of denitrifying bacteria to be decreased.
		2025 Vol. 44 (2): 223-234 [Abstract] ( 76 ) HTML (1 KB) PDF (14386 KB) ( 22 )

	235	Effects of Three Microalgal Species and Densities on Physiological Metabolism, and Carbon and Nitrogen Budgets of Pearl Oyster Pinctada fucata martensii
		REN Peng, ZHANG Xingzhi, LIU Jingcan, LYU Shuguo, WANG Aimin, LIU Chunsheng
		DOI: 10.16378/j.cnki.1003-1111.24106
		To elucidate the effects of different microalgae species and concentrations on physiological metabolism and carbon and nitrogen budget of pearl oyster Pinctada fucata martensii, the pearl oyster with shell length of (55.06±1.22) mm and wet body weight of (23.26±1.12) g were reared in plastic barrels of 200 L sand-filtered seawater, and was fed microalgae Isochrysis galbana, Chaetoceros muelleri and Platymonas subcordiformis at concentrations of each alga 2.2, 4.4 and 6.6 mg/L (dry weight), respectively, at water temperature of (26.0±0.5) °C. The physiological and metabolic indices including food ingestion rate, oxygen consumption rate, ammonia excretion rate, fecal excretion rate and calcification rate of Pinctada martensii under the interaction of microalga species and concentrations were investigated, and then carbon and nitrogen budget of the pearl oyster was calculated. The results showed the food ingestion rate of the pearl oyster was significantly influenced by microalgal species and concentrations (P<0.05), with from 13.36 to 39.14 mg/(g·h). In the I. galbana group, the pearl oyster and food ingestion rates in a trend of initially increasing and then decreasing with food concentration, while in the other two treatment groups, the food ingestion rates were found to be increased with food concentration. The respiration and ammonia excretion rates of the pearl oyster were significantly influenced by microalgal species, with lower respiration rates [0.63—1.34 mg/(g·h)]in P. subcordiformis group, and higher ammonia excretion rates [0.44—0.71 mg/(g·h)]in C. muelleri group. Growth carbon was significantly influenced by microalgal species and concentration in carbon budget of the pearl oyster. The proportion of growth carbon was shown to be increased with the increase in food concentration under the experimental conditions, with the maximal proportion of growth carbon in the I. galbana group, followed by the C. muelleri group, and the P. subcordiformis group at the same microalgal concentration. The pearl oyster has a higher proportion of excreted nitrogen (36.75%—81.63%) and a lower proportion of growth nitrogen (-26.91%—29.48%) in nitrogen budget under low microalgal concentration condition (2.2 mg/L). At higher microalgal concentrations (4.4 and 6.6 mg/L), however, the maximal proportion of growth nitrogen was observed in the I. galbana group, followed by the P. subcordiformis group, and the lowest in the C. muelleri group. The parameters of various physiological metabolisms and carbon and nitrogen budgets were quantified in the pearl oyster under different microalgal species and concentrations. The findings can provide reference data for enhancing the farming techniques of bivalves and investigating their ecological adaptability mechanisms.
		2025 Vol. 44 (2): 235-243 [Abstract] ( 67 ) HTML (1 KB) PDF (1060 KB) ( 21 )

	244	Methylation Analysis of Promoter of Dmc1 Gene Related to Meiosis in Hybrid Triploid Loach Misgurnus anguillicaudatus
		MA Kexin, LI Yifan, YANG Yueyao, LI Chuan, GUO Wenxuan, ZHUANG Zixin, WANG Wei, ZHOU He
		DOI: 10.16378/j.cnki.1003-1111.23099
		In order to investigate the important role of DNA Meiotic Recombinase 1 (Dmc1) in the infertility mechanism of the hybrid triploid loach Misgurnus anguillicaudatus(4n ♀ × 2n ♂), the Dmc1 gene was cloned from the hybrid triploid loach, and the physicochemical properties and phylogenetic position of the gene were analyzed by bioinformatics. The methylation and expression levels of the promoter region of Dmc1 gene were analyzed by bisulfite sequencing (BSP) and RT-PCR in the gonadal tissues of female and male offspring of loach triploid crosses and their parents. The results showed that the Dmc1 gene had the full length of 3895 bp, and an open reading frame (ORF) of 1029 bp encoding 342 amino acids, with the predicted molecular weight of 37.85 ku, and the theoretical isoelectric point (pI) of 6.95. Multiple sequence alignment showed that the amino acid sequence of Dmc1 in the loach was similar to that of other fish in Cypriniformes and less similar to arthropods. The phylogenetic tree revealed that the loach clustered with other osteichthyans in terms of Dmc1 evolution. BSP analysis showed that the methylation rates of the Dmc1 promoter region were 100% in the tetraploid maternal parent, 80.0% in diploid paternal parent, and 82.2% in triploid offsprings. There was higher methylation rate of the Dmc1 promoter region in the male offspring of triploids than that in the diploid paternal parent, with the significantly lower expression level of the Dmc1 gene than that in the diploid paternal parent. The methylation rate of the Dmc1 promoter region was shown to be lower in the female offspring of triploids than that in the tetraploid maternal parent, with significantly higher expression level of the Dmc1 than that in the tetraploid maternal parent. Pearson correlation coefficient analysis indicated that the methylation rate of the Dmc1 promoter region was negatively correlated with its expression level (r =-0.986, P=0.014). These findings suggested that the expression level of the Dmc1 gene in different ploidy loach was negatively regulated by methylation of the promoter region, leading to the speculation that the DNA methylation rate of the Dmc1 gene was correlated with the meiotic abnormalities and low fertility of triploid loaches. These findings provide theoretical basis for unraveling the molecular mechanisms underlying the infertility of hybrid triploid loaches.
		2025 Vol. 44 (2): 244-253 [Abstract] ( 54 ) HTML (1 KB) PDF (22069 KB) ( 12 )

	254	Effect of Sodium Acetate Supplementation on Nutrient Removal Efficiency of Laver Pyropia-Processing Wastewater by Microalga Scenedesmus obliquus
		WANG Hongyan, ZHANG Huai, JIANG Houquan, GUO Xiangxu, ZHAO Pu, WANG Xinmiao, ZHENG Shiyan, WANG Qiang
		DOI: 10.16378/j.cnki.1003-1111.24048
		To explore the impacts of carbon source supplementation on the purification efficiency of Pyropia-processing wastewater (PPW) by microalga, Scenedesmus obliquus was selected as the research object and sodium acetate as the supplementary carbon source. The growth performance of S. obliquus and the removal efficiency of pollutants in PPW were investigated under different sodium acetate concentrations (0, 0.25, 0.50, 0.75, 1.00, and 1.50 g/L). The results showed that the addition of exogenous sodium acetate led to an obvious increase in the initial concentration of chemical oxygen demand (COD) in PPW. However, S. obliquus was still effective in removing pollutants from PPW (P<0.05). After 5—7 d of culture, the maximal removal rate was shown to be 81.97% in COD, 88.41% in total nitrogen (TN), 94.10% in total phosphorus (TP), and 91.23% in phycobiliprotein (PP) from PPW by S. obliquus under different concentrations of sodium acetate. The addition of 80 mg/L chitosan to flocculate algal cells after culturing S. obliquus resulted in significant increase in the maximum COD elimination rate to 91.43% (P<0.05). The maximal biomass (0.81 g/L) and soluble sugar (168.61 mg/g) contents were observed in S. obliquus in the 1.50 g/L sodium acetate group for 7 days culture, 63.54% and 1.06 times higher than those in the control group (P<0.05). The findings suggest that under exogenous supplementation of 0.25—1.50 g/L sodium acetate conditions, S. obliquus cultivated in PPW can accumulate higher biomass and soluble sugar content, with effectively reducing the levels of pollutants in PPW simultaneously. In addition, the COD removal rate is found to be further improved by adding moderate chitosan for flocculation at the end of microalgae culture.
		2025 Vol. 44 (2): 254-263 [Abstract] ( 58 ) HTML (1 KB) PDF (5407 KB) ( 26 )

	264	*Habitat Suitability of Chub Mackerel Scomber japonicus* in the East China Sea based on Vertical Water Temperature**
		NI Yongyi, WEN Jian, LI Yikai, YU Wei, WU Feng
		DOI: 10.16378/j.cnki.1003-1111.24032
		The impact of climate variability on the habitat of chub mackerel Scomber japonicas, an economically important pelagic fish species, can be exploited to provide scientific references for resources management. In this study, the habitat suitability index (HSI) on the fishing ground of chub mackerel was calculated in the East China Sea based on the environmental data of vertical water temperature at depths of 2.5 m, 25.0 m and 50.0 m and the Pacific decadal oscillation (PDO) index from 1977 to 2015. The spatio-temporal distributions of potential habitat of chub mackerel were compared among the different phases of PDO. The results showed that the anomalies of water temperature at different depths were significantly positively correlated with the PDO index. During the cold PDO, the anomalies of water temperature at different depths tended to be high, the range of suitable areas of water temperature tended to be more, the ratio of suitable areas of water temperature at 2.5 m and 50.0 m was obviously higher than that during the warm PDO, the ratio of unsuitable areas of water temperature at 2.5 m was significantly lower than that during the warm PDO, and the gravity center of the suitable index of water temperature at different depths shift northwestward. Compared to the warm PDO, the habitat suitability and the ratio of suitable habitat were higher, the ratio of unsuitable habitat was lower, the longitudinal gravity center of suitable habitat shift westward and the latitudinal gravity center of suitable habitat shifted northward during the cold PDO. The findings indicate that the warm and cold PDO regime shift yield significant impacts on variations in habitat distribution of chub mackerel in the East China Sea by changing the vertical water temperature on the fishing ground.
		2025 Vol. 44 (2): 264-273 [Abstract] ( 61 ) HTML (1 KB) PDF (8796 KB) ( 14 )

	274	Screening and Application of Chinese Herbal Medicines to Inhibit Photobacterium damselae subsp. damselae
		LIANG Yifan, WU Jianshao, LI Huiyao, YANG Quihua, GUO Songlin, LI Zhaojie, LIN Qi
		DOI: 10.16378/j.cnki.1003-1111.23074
		In order to screen out the Chinese herbal medicines for safe and efficient prevention and treatment of skin ulceration syndrome in sea cucumber Apostichopus japonicus, in vitro bacteriostatic effects of 20 types of Chinese herbal medicines on Photobacterium damselae subsp. damselae (PDD) from the sea cucumber were determined by using inhibition circle method and modified microdouble dilution method on MH medium (Mueller-Hinton Agar), and 2216E liquid medium (2216E liquid medium), includingFructusChebulae, Radix et Rhizoma Rhei, Radix Isatidis, Spica Prunellae, Fructus Mume, Cortex Phellodendri, Rhizoma Polygoni Cuspidati, Cortex Fraxini, Rhizoma Coptidis, Radix Paeoniae Alba, Galla Chinensis, Radix Paeoniae Rubra, Herba Andrographis, Fructus Schisandrae, Herba Artemisiae Annuae, Flos Lonicerae, Radix Pulsatillae, Radix Scutellariae, Pericarpium Granati, Folium Isatidis, which were crushed and,sieved and 2 g of medicinal powder was soaked in 150 mL of double distilled water for 30 min, boiled over high heat, and boiled on low heat for 20 min, and concentrated to 20 mL. The toxicity of the screened Chinese herbal medicines with good antibacterial to the sea cucumber with body weight of (0.4±0.15) g was examined and the Chinese herbal medicines with good antibacterial effect were added into the diets which were fed the sea cucumber with body weight of (18.5±5.4) g for 28 days and then artificially challenged with PDD, to calculate the relative protection rate. The results showed that the aqueous extracts of six herbs, including Fructus Chebulae, Radix et Rhizoma Rhei, Cortex Fraxini, Rhizoma Coptidis, Galla Chinensis, Pericarpium Granati, had bacteriostatic effects on the PDD, Galla Chinensis having the strongest bacteriostatic and bactericidal effects, with the minimum inhibitory mass concentrations (MIC) of 1.56 g/L and the minimum bactericidal mass concentrations (MBC) of 6.25 g/L. The MIC of 3.13 g/L and MBC of 25 g/L were observed in Pericarpium Granati, and MBC from 6.25 g/L to 25 g/L in Fructus Chebulae, Radix et Rhizoma Rhei, Cortex fraxini and Rhizoma Coptidis, with good bactericidal effect. The descending order of the acute toxicity of the three herbal medicines to juvenile sea cucumber was expressed asGalla Chinensis>Fructus Chebulae>Pericarpium Granati, with the LC₅₀ of 0.417 g/L in 24 h, 0.209 g/L in 48 h, 0.174 g/L in 72 h and 0.145 g/L in 96 h for Fructus Chebulae, and the LC₅₀ of 0.67 g/L in 24 h, 0.318 g/L in 48 h, 0.211 g/L in 72 h and 0.172 g/L in 96 h for Pericarpium Granati. There was cumulative mortality rate of 40% in the control group in 15 d, and the relative protection rate of 92%, 75% and 58.4% in the drug-addition groups in the 15 d,with the order of 3% added group>1% added group>5% added group. The findings indicated that Pericarpium Granati significantly improved the disease resistance of sea cucumber, with the best effect in 3% additive group.
		2025 Vol. 44 (2): 274-283 [Abstract] ( 68 ) HTML (1 KB) PDF (5013 KB) ( 61 )

	284	Pollution Characteristics and Treatment Effects of Aquaculture Wastewater in the Core Area of Changjiang River Delta
		ZHU Zewei
		DOI: 10.16378/j.cnki.1003-1111.24006
		In order to understand the pollution characteristics of aquacultural wastewater in freshwater ponds in the demonstration zone of green and integrated ecological development in the Changjiang River Delta (Wujiang District, Qingpu District, Jiashan County) and the treatment effect of the wastewater treatment system, the water quality indices were monitored in the of 46 freshwater farms in the core area of the Changjiang River Delta, and the treatment effect of the wastewater in 30 of them were monitored in November—December 2022 (Winter) and June—August 2023 (Summer). Water quality labeling index (WQI) and cluster analysis (CA) were used to analyze all monitoring sites. It was found that the average annual concentrations were (2.80±1.53) mg/L in total nitrogen (TN), (0.49±0.33) mg/L in total phosphorus (TP) and (18.97±17.81) mg/L in permanganate index (COD_Mn) in the wastewater of freshwater ponds in the core area of the Changjiang River Delta. The rates of conforming wastewater was 58.70% in summer and 82.61% in winter, with the most serious wastewater pollution from Macrobrachium rosenhali (WQI mean 6.8), followed by Micropterus salmoides (WQI mean 6.4), and the least serious from Eriocheir sinensis (WQI mean 4.2). The tailwater purification facilities investigated in this study had good purification effect on aquaculture tailwater, all meeted the discharge standards, with the annual removal rates of (49.02±17.38)% in TN, (34.50±21.15)% in TP and (39.93±23.58)% in COD_Mn in aquaculture tailwater. The findings provided scientific basis and reference with the targeted configuration of tailwater treatment facilities for main breeding species or varieties in the core area of the Changjiang River Delta, reduced the construction cost and operation and maintenance cost, and improved the purification effect.
		2025 Vol. 44 (2): 284-294 [Abstract] ( 72 ) HTML (1 KB) PDF (16625 KB) ( 13 )

	295	Requirement of Largemouth Bass Juveniles for Dietary Lysine
		ZHU Xifeng, LI Shiyang, HU Junru, LIANG Haohui, HUANG Yanhua, ZHOU Meng, WANG Guoxia
		DOI: 10.16378/j.cnki.1003-1111.24030
		In order to probe the effects of diary lysine level on growth performance, digestion, and antioxidant capacity of juvenile largemouth bass Micropterus salmoides, juvenile largemouth bass with average body weight of approximately 0.07 g were reared in nylon cages with water volume of 75 L at stocking density of 150 individuals per cage disposed in an outdoor aquaculture system, and fed the isonitrogenous and isoenergetic diets containing lysine level of 1.31%, 1.97%, 2.64%, 3.30%, 3.97 and 4.63% for 30 days. The results showed that there was the minimal survival rates in the juvenile largemouth bass in 1.31% lysine groups and 1.97% lysine (P<0.05), with the first increase and then decrease in weight gain rate and specific growth rate in the juvenile largemouth bass fed the diets containing lysine, the maximal level in 2.64% lysine group, as the dietary lysine level increase. The maximal values for trypsin activity, intestinal villus height, muscular thickness, and the number of goblet cells were observed in the juvenile largemouth bass in 2.64% lysine group. The pattern of initial rise and followed by decline in content of malondialdehyde and the activity of peroxidase was found in the in the test fish, with the maximumt in the 3.97% lysine group. According to the specific growth rate as the evaluation index, largemouth bass juveniles had the lysine requirement of 2.65%, accounting for 5.19% of dietary protein, under this test condition based on the broken line model analysis.
		2025 Vol. 44 (2): 295-302 [Abstract] ( 68 ) HTML (1 KB) PDF (2422 KB) ( 9 )

	303	*Difference Analysis in Intestinal Flora of Juvenile Echiura Worm Urechis unicinctus* with Different Growth Rates**
		DONG Haomiao, WANG Fangyi, XU Dong, JIAO Xudong, WANG Weizhong
		DOI: 10.16378/j.cnki.1003-1111.24045
		In order to explore the relationship between growth difference of juvenile echiura worm Urechisunicinctus and its intestinal microbiota with different growth rates, the composition and changes in bacterial flora were analyzed in the intestines especially dissected of the juvenile echiura worm anesthesized by MS-222 with body weight of greater than 700 mg in fast-growth group (FG group) and with body weight of less than 300 mg in slow-growth group (SG group) sampled in three 100 cm² substrate regions in the same culture pond by 16S rRNA high-throughput sequencing. The results showed that greater diversity of intestinal flora species was found in the juvenile echiura worm in FG group than that in FG group, with dominant bacteria in Proteobacteria and Firmicutes in the intestine. There was the maximal relative abundance of Ralstonia in FG group and significantly higher than that in SG group, while there was the maximal abundance of Candidatus_hepatoplasma in SG group and significantly higher than that in FG group.LEfSe analysis revealed that more Pseudomonas, which was speculated to promote individual growth, was observed in FG group, with more Candidatus_hepatoplasma in SG group, or the marker genus with too slow growth rate. Functional prediction showed that the relative abundance of bacteria involved in cellular processes and signaling was significantly higher in FG group than that in SG group, while the relative abundance of microorganisms involved in cell growth and death function groups accounted for a significant advantage in SG group, indicating that there was a correlation between the growth rate of echiura worm and the intestinal flora. The findings can provide theoretical guidance for the healthy breeding and efficient cultivation of echiura worm.
		2025 Vol. 44 (2): 303-312 [Abstract] ( 55 ) HTML (1 KB) PDF (9824 KB) ( 22 )

	313	Effect of Tussah Immunoreactive Substances on Growth and Immunity of Sea Urchin Strongylocentrotus intermedius
		CHEN Xinghe, JIA Xinyue, WEN Zhixin, LI Yajie, WANG Dong, DU Xingfan
		DOI: 10.16378/j.cnki.1003-1111.23092
		To investigate the effect of tussah immunoreactive substances (TIS) on growth and immune function of sea urchin Strongylocentrotus intermedius, the sea urchin with initial body weight of (26.7±0.2) g were reared in a 97 L tank at stocking density of 30 individuals per tank, and fed the diets containing 0% (control group), 0.5, 1.0, and 2.0% of TIS for 60 days. At the end of the experiment, growth performance and immune indices were measured in body coelomic fluid. The results showed that the specific growth rate and shell diameter growth rate were found to be increased in the sea urchins in the 0.5% and 1.0% TIS-fed groups compared to the control group, without significant differences, and significant increase in the gonado-somatic index (P<0.05). The total amount of flavor amino acids was shown to be increased by 5.4% in the gonads of sea urchins in the 1.0% TIS group compared to the control group. Moreover, there was more than 10% increase in the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in unsaturated fatty acids. The sea urchin had significant activities of lysozyme and superoxide dismutase in each TIS-supplemented group as well as the activity of catalase in the sea urchin gonads in the 0.5% dose group (P<0.05). In summary, diet supplemented with 0.5%—1.0% TIS can lead to enhance the growth and improve the immune response of the sea urchin. These findings offer a theoretical framework for integrating TIS into sea urchin formula feed.
		2025 Vol. 44 (2): 313-319 [Abstract] ( 57 ) HTML (1 KB) PDF (1354 KB) ( 35 )

Overview and Specific Topic

	320	A Review of Progress on Feeding Selectivity of Filter-Feeding Shellfish on Food Microalgae
		SONG Guangjun, SONG Lun, LIU Yin, WANG Kun, LI Nan
		DOI: 10.16378/j.cnki.1003-1111.24105

		2025 Vol. 44 (2): 320-326 [Abstract] ( 116 ) HTML (1 KB) PDF (1000 KB) ( 67 )

	327	Research Progress on Bacterial-Algal Symbiosis Biofilm in Aquaculture Tailwater Treatment: a Review
		ZE Wuge, LI Tiejun, QIAO Ling, YUAN Tao, GUO Yuanming, REN Chengzhe
		DOI: 10.16378/j.cnki.1003-1111.24075

		2025 Vol. 44 (2): 327-340 [Abstract] ( 113 ) HTML (1 KB) PDF (2437 KB) ( 47 )