Eliminate factors inhibiting redclaw farming from reaching its full potential

Summary

Two main objectives of the NQCFA have been to improve the growth potential though selective breeding and the development of a hatchery to produce consistent quality seed stock for industry. Thanks to RIRDC the Selective Breeding Project (SBP) has been realised and is being continued by a NQCFA member. The hatchery has also been developed to a point where significant quantities of S3J’s (craylings) are successfully incubated each year. This has changed redclaw farming dramatically. We now have enough data from growers and experience to confidently state that the utilisation of both these objectives has resulted in some outstanding results across many farms in Queensland. The full exploitation of these new farming methods is the future of redclaw farming in Australia. However we have three persistent and problematic bottle necks that need to be overcome to fully realize the potential of these new developments. 1. Improve the management of the microbiology within the incubator system to maximize production efficiency, reliability and predictability. We need the tools to take more control over the microbiology within the egg incubators so as to avoid major losses that occur intermittently. 2. Investigate methods to maximise survival of S3J’s from hatchery to pond and formulate best practices for the hatchery operator and farmer. 3. Investigate why significant losses of adult redclaw occur shortly after handling. Especially frustrating when regular handling of the broodstock for the continuation of the selective breeding program results in a steady decline of stock through the course of the breeding cycle.

Program

New and Emerging Animal Industries

Research Organisation

North Queensland Crayfish Farmers Association Inc

Objective Summary

The objectives of this proposed R&D project are threefold: 1. Improve the management of the microbiology within the incubator system to maximize production efficiency, reliability and predictability. The fresh water gramnegative bacterium Aeromonas hydrophila has been identified numerous times over the last 8 years as the cause of high mortalities, specifically in stage 2 larvae, sometimes resulting in a complete loss of production. The longterm viability of the hatchery depends on finding solutions to manage these aggressive bacteria. Methods have been found that work but need refining by microbiologists within the laboratory. In addition protocols have to be developed to best implement these measures and ensure the longterm viability of the hatchery. 2. Investigate & implement methods to maximizing the transition survival from hatchery to pond and formulate best practice for the hatchery operator and farmer. For the first time with S3J’s produced from a hatchery we can stock an exact quantity into a pond. This means we now have the techniques to determine exact survival and biomass at the end of the production cycle. Numbers from the last couple of years suggest that around 50 % of all stocked craylings survive till the end of growout. The question now is: where are these 50 % lost in the cycle? Is it at initial stocking or through natural attrition throughout the growout phase? Investigations need to be carried out to better understand the needs of S3J’s in the early months of stocking. 3. To determine the cause and establish a solution, to a long standing industry problem – that of post handling mortality. This is especially important with the advent of hatchery technology where the survival of pedigree broodstock is critical to the continued propagation of improved stock.

Project Code

PRJ-009388

Project Stage

Closed

Project Start Date

Saturday, May 31, 2014

Project Completion Date

Sunday, March 31, 2019

Journal Articles From Project

Not Available

National Priority

Frontier technologies for building and transforming Australian industries

National Priority

Adoption of R&D

National Priority

NAP-Enhance industry success through targeted industry-specific RD&E

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