Importance of the freshwater rotifer Brachionus angularis for improved survival rate of early life‐history stages of pangasius catfish, Pangasianodon hypophthalmus

This study aimed to determine the optimal live feed regime (i.e., initial feeding moment, density, and frequency) for maximum growth and survival of pangasius catfish (Pangasianodon hypophthalmus) early life history stages. The first experiment assessed the optimal initial feeding moment (30, 36, 42, and 48 h post hatching, hph). The second experiment assessed feeding density (3, 5, 8 and 11 individuals per mL, ind/mL) at the optimal initial feeding moment (30 hph) which was the best result from the first experiment. The third experiment assessed optimal feeding frequency (1, 2, 4, and 6 times per day) at the optimal initial feeding moment (30 hph) and density (8 ind/mL) which was drawn upon from the second experiment. All experiments were conducted in 20 L containers containing 20 hph P. hypophthalmus larvae at a density of 10 ind/L and fed rotifers (Brachionus angularis) for 3 days and then water fleas (Moina macrocopa) for 7 days. The first experiment demonstrated that larvae initially fed at 30 hph exhibited a significantly higher survival rate (24%) than larvae initially fed at 36, 42, and 48 hph (19%, 16%, and 16%), respectively. The second experiment demonstrated that larvae fed at 8 and 11 ind/mL densities exhibited significantly higher survival rates (32% and 32%) than larvae fed at 3 and 5 ind/mL densities (13% and 23%), respectively. The third experiment demonstrated that the highest survival rate (66%) was obtained when larvae were fed 6 times per day. These results provide valuable insights regarding the optimal live feed regime for better growth and survival of P. hypophthalmus larvae, which are commercially important and numerously cultured throughout the Mekong Delta region.

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Oceanographic influence on the early life-history stages of benthic invertebrates during the polar night

Polar Biology ◽

10.1007/s00300-021-02918-0 ◽

2021 ◽

Author(s):

Kirstin Meyer-Kaiser ◽

Hongju Chen ◽

Xiaoshou Liu ◽

Samuel R. Laney

Keyword(s):

Life History ◽

Benthic Invertebrates ◽

Early Life ◽

Early Life History ◽

Polar Night ◽

Life History Stages

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Significance of Egg and Larval Size to Recruitment Variability of Temperate Marine Fish

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f91-215 ◽

1991 ◽

Vol 48 (10) ◽

pp. 1820-1828 ◽

Cited By ~ 82

Author(s):

Pierre Pepin ◽

Ransom A. Myers

Keyword(s):

Life History ◽

Marine Fish ◽

Early Life ◽

Univariate Analysis ◽

Early Life History ◽

Fish Populations ◽

Larval Size ◽

Larval Phase ◽

Life History Stages ◽

Recruitment Variability

Recruitment variability is commonly associated with fluctuations in abundance of marine fish populations. Previous studies have focussed on stock-specific correlative or mechanistic models or on comparisons of recruitment variations of several stocks or species. The purpose of this study is to determine whether recruitment variability of commercial marine fish populations is associated with either size or the duration of early life history stages. The analysis was performed with data from 86 stocks representing 21 species of commercial marine fish. Univariate analysis shows that neither egg size nor the length at hatch is significantly correlated with recruitment variability. The change in length during the larval phase, which is representative of the duration of the stage, is significantly positively correlated with recruitment variability. Multivariate analysis shows that recruitment variability increases with increasing length at metamorphosis but that recruitment variability is poorly associated with length at hatch. The degree of serial correlation is related to the relative duration of egg and larval stages. The results clearly indicate that recruitment variability is linked to characteristics of early life history stages.

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