配合饲料投喂量和粒径对绿盘鲍稚鲍生长和存活的影响

在水温15.8~24.7℃下,将小规格(壳长为1.03±0.02 cm)和中规格(壳长为1.57±0.03 cm)绿盘鲍(GS-02-003-2018)(皱纹盘鲍Haliotis discus hannai Ino♀×绿鲍H.fulgens♂)稚鲍分成A、B、C和D 4个组,饲养在240 mm×170 mm×285 mm、容积8 L的水族箱内:A组投喂粒径165μm的饲料,投喂率为2%、3%、4%和5%;B组投喂率为4%,用粒径198μm和165μm饲料混合投喂,二者比例分别为1:0、7:3、5:5和3:7;C组投喂粒径198μm的饲料,投喂率为2%、3%、4%和5%;D组投喂率为4%,用粒径245μm和198μm饲料混合投喂,二者比例分别为1:0、7:3、5:5和3:7,研究了配合饲料投喂量和粒径对不同规格稚鲍生长和存活的影响。用壳长日增长(DLG)、体质量日增长(WLG)以及壳长特定生长率(LSGR)、体质量特定生长率(WSGR)4个指标来衡量生长情况。结果显示:配合饲料投喂量对稚鲍的生长具有重要影响,不同规格稚鲍适宜的投喂量不同。中规格稚鲍适宜的投喂量为体质量的3%,小规格为体质量的5%;用198μm和165μm颗粒配合饲料以3:7混合投喂小规格稚鲍生长最佳,用245μm和198μm颗粒以1:0混合投喂中规格稚鲍生长最佳;试验结束时各试验组稚鲍存活率均高于88.0%,具有较高的存活率。因此,育苗生产中应根据不同生长阶段选用适宜的投喂量和粒径,以更好地促进稚鲍的生长发育。

Effects of feeding rate and dietary particle size on growth and survival of juvenile hybrid abalone(Haliotis discus hannai Ino♀×H.fulgens♂)

Under the water temperature of 15.8-24.7℃,small size(shell length of 1.03±0.02 cm)and medium size(shell length of 1.57±0.03 cm)green disc abalone(GS-02-003-2018)(Haliotis discus hannai Ino♀×H.fulgens♂)were divided into 4 groups(A,B,C and D),and reared in a 240×170×285 mm aquarium with a volume of 8 L:in Group A the juveniles were fed with compound feed with a particle size of 165μm at feeding rate of 2%,3%,4%,or 5%;in Group B the juveniles were fed with compound feed with a particle size of 198μm and 165μm mixed feed at the ratio of 1:0,7:3,5:5 or 3:7 at feeding rate of 4%;in Group C the juveniles were fed with compound feed with a particle size of 198μm at feeding rates were 2%,3%,4%,or 5%;in Group D the juveniles were fed with a mixed particle size feed of 245μm and 198μm at the ratios of 1:0,7:3,5:5 and 3:7 at feeding rate of 4%.The effects of feeding rate and dietary particle size on the growth and survival were studied in juvenile abalone with different specifications.The daily growth of shell length(DLG),daily growth of body mass(WLG),specific growth rate of shell length(LSGR)and specific growth rate of body mass(WSGR)were measured for the growth.SPSS and Excel software were used for data analysis and mapping.The results showed that growth of the juvenile of hybrid abalone was significantly affected by the feeding rate of compound feed,with different effects of suitable feeding amount of different sizes on growth of juvenile abalone.The medium size juvenile abalone had suitable feeding rate of 3%and small size juvenile abalone had suitable feeding rate of 5%.The growth of the juvenile abalone was influenced by particle size of compound feed,and the best growth was observed in the small-size juvenile abalone fed with mixed particles of 198μm and 165μm at a ratio of 3:7,and the best growth was found in 245μm and 198μm mixed diet at a ratio of 1:0 in the medium size juvenile abalone.Survival rate was over 88.0%in the juvenile abalone in each experimental group.The findings indicated that the feeding amount and particle size of compound feed had an important impact on the growth of juvenile abalone with different sizes.Therefore,the appropriate feeding amount and particle size should be selected according to different growth stages in order to better growth and development of juvenile abalone.