Embryonic and Larval Development of Stinging Catfish, Heteropneustes fossilis, in Relation to Climatic and Water Quality Parameters

Abstract

In terms of hatchery-based seed production, one of the most important aquaculture species in Bangladesh is the stinging catfish (Heteropneustes fossilis). Scientific and evidence-based embryonic and larval development research on this fish species in the context of climate change is limited. This experimental study was conducted via induced breeding of stinging catfish using a conventional hatchery system, rearing the larvae in hapas placed in ponds. A series of microscopic observations using a trinocular digital microscope and an analysis of the relationship between larval growth and climate-driven water quality parameters such as temperature, pH, dissolved oxygen, total dissolved solids, alkalinity, and ammonia were performed. During embryonic development, the first cleavage was observed between 30 and 35 min of post-fertilization. Embryonic development (ranging from the 2-cell to the pre-hatching stage) took 21:00 h. Hatching occurred at 22:30 to 23:00 h after fertilization, with an average larvae length of 2.78 ± 0.04 mm. In the post-hatching stage, four pairs of tiny barbels appeared at 36:00 h, and the larvae started feeding exogenously after 72:00 h. These larvae fully absorbed their yolk sacs on the 6th day and attained an average length of 6.44 ± 0.06 mm. Aerial respiration of the larvae was investigated through naked-eye observation on the 10th day of hatching. The average length of the larvae was 32.00 ± 2.0 mm at the end of the 30-day post-hatching observation period. Bivariate correlation analysis showed significant correlations between key climatic variables and water quality parameters under hapa-based larval-rearing conditions. According to canonical correlation analysis, the first canonical function revealed the highest significant correlation between the two sets of variables (r1 = 0.791). The response variable weight of larvae (6.607) was linked to two explanatory variables: pH (0.321) and dissolved oxygen (0.265). For the second canonical correlation function, a positive correlation (0.431) was observed between the two sets of variables. Larval weight (−18.304) was observed to be linked to climatic variables, including air temperature (−0.316) and surface pressure (0.338). Results of this study reveal the subtle correlation between larval growth and water quality driven by climatic variables.

Hormonal (sGRnH) Doses Optimization with the Ages of Brood Fish in Induced Breeding of Mystus tengara (Hamilton, 1822)

“…of hatching appeared*100)/ No. of eggs in subsample [16,17] But this study applied another formula to calculate the fertilization rate and hatching which resembled to recent study on embryonic and larval development of stinging catfish [19]. Consequently hatching rate was found to be higher than fertilization Rate in some weeks which also assimilate with the study of Mahalder et al [19].…”

Multifaceted Linkages among Eco-Climatic Factors, Plankton Abundance, and Gonadal Maturation of Hilsa Shad, Tenualosa ilisha, Populations in Bangladesh

“…Furthermore, further studies are needed to clarify the specific mechanisms underlying the relationship between phytoplankton abundance and gonadal maturation in Hilsa fish. Detailed investigations into the nutritional composition of phytoplankton species and their effects on reproductive hormones and gamete development can provide deeper insights into the biological processes involved [135][136][137][138][139][140]. However, this variation in gonad development, food and feeding habits, and feeding biology might be the next focus of research through transcriptomic profiling of kidney, brain, muscle, and gonad samples of T. ilisha in the six diverse habitats of Bangladesh.…”

Effects of Commercial Probiotics on the Growth Performance, Intestinal Microbiota and Intestinal Histomorphology of Nile Tilapia (Oreochromis niloticus) Reared in Biofloc Technology (BFT)

“…Recent data indicate about 50% of the world's fish supply is sourced from aquaculture [3,4]. Bangladesh, like other tropical countries, is widely recognized as one of the premier locations for freshwater aquaculture [5,6], due to its abundant resources and favorable agroclimatic conditions [7]. Bangladesh ranked fifth worldwide with a total fish production of 4.76 million MT in 2021-2022, while also holding the fourth position in tilapia production globally and the third in Asia [4,8].…”