C. Hendry, L.C. Halfyard
Abstract:
A study was performed to determine the necessity of providing live feed (i.e., Artemia nauplii) to larval Atlantic wolffish (Anarhichas lupus L.) during the first-feeding stage. The study also tried to evaluate whether the Artemia require enrichment with essential fatty acids (EFA), or are they nutritious enough by themselves with their natural EFA content? In various other marine fish, the presence of live feed promotes the instinctive predatory response, and they are also thought to supply exogenous digestive enzymes that the larvae are unable to synthesize themselves. Newly hatched wolffish were raised to 40 days post-hatch in recirculated seawater raceways at 8°C and supplied dry feed and Artemia naupii (where necessary) under automatic timer control. Results indicated that all measured growth parameters (wet weight, body length, specific growth rate) were significantly higher with diets supplemented with unenriched Artemia versus no Artemia, and such growth parameters were significantly highest for diets supplemented with the enriched Artemia. Survival followed the same trend as the growth parameters between different treatments. It is therefore necessary to provide larval wolffish with dry feed supplemented with enriched Artemia to obtain the best growth performance and survival.
(Department of Fisheries and Oceans, Biological Station, St. Andrews, NB E0G 2X0, Canada)