Effect of Stocking Density on Growth, Water Quality Changes and Cost Efficiency of Butter Catfish (Ompok bimaculatus) during Seed Rearing in a Biofloc System

Abstract

Biofloc technology is a modern-day high-density fish culture system employing heterotrophic conversion of nitrogenous waste into useful flocs for water quality control and improved welfare. However, optimization of the stocking density for the target species during seed rearing is the key to a successful farming operation. The study evaluated the effect of different stocking density on the growth, feed utilization, digestive physiology and economics in a biofloc-based seed rearing of butter catfish, O. bimaculatus. Advanced fry (1.21 ± 0.08 g) was reared in a zero-water exchange biofloc system for 90 days at stocking densities of 0.5 g/L(T1), 1.0 g/L(T2), 1.5 g/L(T3) and 2.0 g/L(T4). The observed water quality indicates a reduction in DO and pH in T4, while the total ammonia nitrogen and nitrite levels remained low in T1. Among the groups, highest weight gain was noticed in the lowest stocking density (0.5 g/L) (p < 0.05), which coincides with a better feed conversion ratio. Similarly, the digestive enzyme (protease, amylase, and lipase) secretion was higher in T1. Profitability assessment describes the possibility of low profit in T4, in the case where the fish’s sale price is based on harvested size. T1 showed higher individual growth and higher profit. Overall, a low stocking density of 0.5 g/Lis optimum for augmenting growth, feed utilization, physiological function and economic performance of O. bimaculatus. The study provides direction for a low-stocking oriented ecological and economically sustainable method of seed production of butter catfish in a biofloc system.

A Novel Risk-Based Quantifiable Approach to Biosecurity Measures in Biofloc Units of West Bengal, India: Implications for Consumer Safety

“…So a negative correlation seems apt, moreover, suggesting the proper functioning of the units. The negative role of pH has been previously studied and the negative correlation seems fitting (Majhi et al 2023). However, TDS is a good determinant of biofloc and the negative correlation observed in our study could have been due to any water treatment process being performed (unknowingly) or a reduced organic load due to plankton-crash (Kazemi et al 2022).…”

Catfishes: A global review of the literature

“…Dunham and Elaswad [ 97 ] emphasized the significance of water quality, temperature, and dissolved oxygen levels in their review, suggesting that proper management of these factors can substantially improve overall welfare and productivity. Similarly, Majhi et al [ 98 ] demonstrated that the implementation of biofloc-based water treatment systems improved water quality, reduced stress, and enhanced growth performance, supporting the notion that ecological factors play a significant role in catfish welfare. Handling and transport are key areas where catfish welfare is paramount, as these processes can induce stress, compromising immune function and increasing disease susceptibility [ 99 , 100 ].…”

The concept of “state fishes of India”: Current status, knowledge gaps, and strategic plans for conservation and sustainable utilization

“…All these imply that conservation aquaculture has the potential to reverse the status of exploited fish stock in the wild by enhancing the natural populations and reducing the pressure on capture fisheries (Diana, 2009). Such efforts are required for the conservation and effective utilization of all state fish species, including C. chitala (Mitra et al, 2018), mahseer (NAAS, 2018Pinder et al, 2019), O. bimaculatus (Biswas et al, 2023), andT. ilisha (NAAS, 2018).…”