Freshwater fish seed quality in Asia.

Abstract

The rapid development of inland aquaculture in Asia has been based on the ready availability of fish seed to farmers. Although seed of the major cultured species is now produced in large quantities in hatcheries, poor quality is increasingly perceived as a major constraint to the success of fish culture, especially for new entrant farmers and poorer smallholders. However, clarification of the role of seed quality, as opposed to post-stocking management, as the cause of farmers' poor results is often lacking. Furthermore, poor seed quality can have a variety of causes relating to both genetics and management. A participatory methodology is described, 'state of the system' (SoS) reporting, that identifies probable causes of poor seed quality and important researchable issues with the people involved in seed production and distribution networks. SoS reporting may be a useful approach for accelerating accurate analysis and subsequent policy-making of such dynamic situations with, and for, the stakeholders involved. Characteristics of current fish seed networks, and promising strategies for the production and distribution of high quality seed to smallholders, are identified. Improved seed quality will depend both on greater awareness of the problem and on practical methods for its assessment at the hatchery or farm level. The role of institutions in improving, maintaining and monitoring fish seed availability and quality is discussed.

Nursing duration and pond fertilization level affect polycultures of Indian major carp (rohu Labeo rohita and mrigal Cirrhina mrigala ) with monosex Nile tilapia Oreochromis niloticus

“…Overwintering of Indian major carp appears to be particularly attractive when the fish are subsequently raised in low‐input polycultures with stocked or feral tilapia. Given the current paradox of food fish production being relatively extensive and fish seed intensive in much of Asia (Little, Satapornvanit & Edwards 2002), the potential importance of prolonged nursing becoming more widespread is clear.…”

Fish Seed Production for National Development in Kenya: Current Status, Challenges, Quality Control and Innovative Strategies for Commercialization

“…Despite this importance, fish seed production remains a challenge to farmers, both in terms of quantity and quality. This challenge seems to affect many parts of the world [4], including Asia [5], but is especially serious in sub-Saharan Africa [6]. In many of these regions, there is an overall trend of intensification of aquaculture due to high demand for fish, therefore availability of high-quality fish seed is essential, to support this growth in fish production.…”

Development and evaluation of a stress challenge testing methodology for assessment of Nile tilapia (Oreochromis niloticus, Linn.) fry quality

“…Poor quality seed has recently been identified as a very significant constraint on the development of the freshwater fish culture industry in Asia (Little, Satapornvanit & Edwards 2001), particularly with regard to discouragement of new entrants and economic losses and/or compromised food security for poor small holders. The seed currently available though plentiful in supply, is generally of low or inconsistent quality as a result of a number of factors: broodstock management practices, stress during nursing and transport or disease.…”

“…The seed currently available though plentiful in supply, is generally of low or inconsistent quality as a result of a number of factors: broodstock management practices, stress during nursing and transport or disease. While schemes are in place to improve broodstock management (Bromage & Roberts 1995), dealing with aquatic disease is ongoing and many reliable hatchery/nursery techniques have been developed (Beveridge & Haylor 1998), there is an immediate requirement for simple and reliable methodologies for determining seed quality at the hatchery or farm gate (Little et al . 1999).…”