The importance of careful breeding
The most critical necessity of any food producer is having good quality production inputs. In a freshwater fish farm, the two key inputs are water and juvenile fish.
Regarding the first key input, water, we are fortunate to be situated along the Murrumbidgee and Murray river catchments, within the Murray cod’s natural habitat. As far as river water goes, our source is both natural and ideal. We also have access to pristine bore water, free from algae, bacteria and other organic matter, which we feed into our recirculating aquaculture systems in our nursery and grow-out systems.
While we are blessed with pristine and natural water as a result of our location, we have needed decades of dedicated breeding to produce multigenerational lineages of Murray cod broodstock that consistently spawn healthy, strong, fast-growing, disease-resistant fish that are highly-suitable for aquaculture and that also have the distinct depth of flavour found in wild Murray cod.
Thus, for any modern Murray cod farm, the most important input is also the most basic – carefully-bred, multigenerational broodstock that produce genetically-stronger larvae that become exceptionally healthy fingerlings that are both hardy enough for restocking wild populations and adaptable enough to be raised in aquaculture.
However, while this core input may seem like a simple matter, raising a sufficient number of high-quality, selectively-bred broodstock can require over 20 years of dedicated breeding. Only then, will a farm have a regular and dependable supply of healthy juvenile fish that are both suited for aquaculture and that will also have the required quality of taste and texture that is desired by end-market consumers.
At Uarah Fisheries, we first began our breeding program in 1977. Since then, for over 40 years, we have carefully bred and selected Murray cod for their natural strength and vitality, initially using a base of wild stock, but progressively incorporating more selectively-bred broodstock with each new season.
Today, we have a sizeable base of multigenerational lineages of Murray cod broodstock producing juvenile fish that excel in an aquaculture environment. Based on our experience and the extensive records we have kept since 1977, we have noticed a substantial and steady improvement in growth rates and disease resistance over the seasons as we have incorporated selective-breeding.
Focusing on natural processes over hormone-induced breeding
An additional feature of the breeding program at Uarah Fisheries is that we utilise natural spawning of Murray cod, rather than the artificial hormone-induced spawning process that is widely-used in the industry. In our experience, we have found that natural spawning in an outdoor pond environment, though more time-consuming and labour-intensive, produces far superior juvenile fish that exhibit favourable characteristics in terms of growth, hardiness and health.
Lastly, though it is often overlooked, another benefit of raising and managing our own broodstock and breeding season is that we can also maintain a longer season to introduce juvenile fish into the farm, and consequently ensure a steady supply of market size fish to the end consumer, all-year round. Likewise, it would be relatively simple to steadily scale up our production by retaining mature fish to add to our broodstock base, and thus, responsively expand our production volumes to meet increases in demand.
Therefore, by controlling the quality and supply of our two key production inputs – namely water and juvenile fish – we are able to ensure the best basis from which to produce a consistent and high-quality fish, that tastes great, and is available all through the year. Considering these above factors, an effective breeding program and selection of good quality broodstock is the fundamental building block of any modern Murray cod farm.
