Manipulation of dietary lipids, fatty acids and vitamins in zooplankton cultures

Abstract

1. A wide range of species that are cultivated in commercial mariculture are planktonic during at least part of their life cycle; for example, the larval stages of shellfish (shrimp and molluscs) and the live feeds (rotifers, brine shrimp, copepods) used in the larviculture of marine fish and shellfish. Over the last decades various techniques have been developed to deliver nutrients to these zooplanktonic organisms either through artificial diets or by manipulating the composition of the live prey fed to the carnivorous stages. This paper reviews the methodology that has allowed aquaculturists to gain knowledge of nutritional requirements and may offer interesting opportunities for ecologists to verify the importance of key nutrients in the natural food chain of marine as well as freshwater ecosystems. 2. Live micro‐algae can be replaced partially or completely in the diet of filter‐feeders such as rotifers, Artemia, shrimp larvae and bivalves, by various types of preserved algae, micro‐encapsulated diets and yeast‐based diets, whereas lipid emulsions and liposomes may be utilized to supplement specific lipid‐and water‐soluble nutrients, respectively. Microbound and micro‐encapsulated diets have been designed to supplement live feed in the culture of micro‐predators such as fish and shrimp larvae. 3. Live prey organisms, in particular rotifers and Artemia, can be ‘bio‐encapsulated’ with a variety of enrichment diets to manipulate their content in certain nutrients, including ω3 highly unsaturated fatty acids (FA) and the vitamins C, A and E. Nevertheless, the enrichment techniques are not applicable for all nutrients and prey organisms. Phospholipid composition is difficult to manipulate through the diet of live feed and the enrichment of the essential FA docosahexaenoic acid (DHA) is hampered in most Artemia species due to the catabolism of this FA following enrichment.

Effect of food quality on rate of growth and development of the pelagic copepod Pseudocalanus elongatus (Copepoda, Calanoida)

“…Lipids used to supplement the food were ICES emulsions obtained from P. Coutteau (University of Gent, Belgium). These emulsions are of the Selco(r) type, containing lipids (62% on wet weight basis), vitamins, antioxidants, preservatives, emulgators and water, and are widely used in aquaculture to supplement extra HUFA to, e.g., Arternia nauplii (Coutteau & Mourente 1997, Coutteau & Sorgeloos 1997. We used ICES series 2 in which 30 % of the lipids consist of the HUFA 2 2 .…”

Total lipids content and fatty acids composition of the rotifer Brachionus plicatilis using artificial enrichments

“…Several rearing trials of rotifers fed with algal species and strains in various forms (fresh, frozen, dried, frozen-dried, concentrated, frozen concentrated, etc) have been carried out in order to support the population growth and survival of the rotifer cultures as well as improve the dietary value of Brachionus plicatilis (Scott and Baynes, 1978;Yufera and Pasqual, 1983;Yamasaki et al, 1984;Lubzens et al,1995;Yufera and Navarro, 1995;Navarro and Sarasquete, 1998;Robert and Trintignac, 1997;Maruyama et al, 1997;Yoshimura et al, 1997;Tzovenis, et al, 2004;Palmtag et al, 2006;Tzovenis et al, 2009;Seychelles et al, 2009;Kotani et al, 2010). In addition, a range of artificial enrichments such as yeasts (Kitajima et al,1979;Hirata, 1980, Kitajima et al, 1980aPenglase et al,2011), microcapsules (Jones et al, 1984;Walford and Lam, 1987;Langdon, 2003) and emulsions (Dhert et al, 1993;Haché and Plante, 2011) were continuously tested in an effort to improve and optimize the nutritional value (total lipids, fatty acids, trace elements, vitamins, amino acids) of the rotifers as they used as biocapsule-boosters to transfer nutrients and support fish larval growth (Lubzens et al, 1989;Coutteau and Sorgeloos, 1997;Rodríguez et al, 1996;Dhert et al, 2001;Lubzens and Zmora, 2003;Conceição et al, 2010).…”

Giant liposomes as delivery system for ecophysiological studies in copepods

“…Liposomes have already been employed for nutrient enrichment of brine shrimp (Artemia salina) larvae, which is one of the key organisms used as food for larval fish rearing in commercial mariculture (for a review, see Coutteau and Sorgeloos, 1997), and have recently been proposed as carriers of nutrients and therapeutic agents in mollusc aquaculture (Lai et al, 2004). Considering the increasing attention that copepods are receiving as alternative live preys to Artemia (Støttrup, 2000;McKinnon et al, 2003), we suggest the use of liposomes as specific nutrient and/or drug carriers for copepod mass cultivation in aquaculture.…”