Dietary histidine supplementation prevents cataract development in adult Atlantic salmon, Salmo salar L., in seawater

Abstract

The aim of the present study was to investigate the cataract preventive effect of dietary histidine regimes in adult Atlantic salmon (Salmo salar L.) in seawater, both through manipulating the dietary histidine level and feeding period. Mean body weight of individually tagged Atlantic salmon at the start of the experiment was 1662 (SD 333) g. Low prevalence of mild cataracts were recorded in the beginning of June. Three fishmeal and fish oil-based extruded diets (crude protein: 375 g/kg and fat: 342 g/kg), differing only in histidine content (low (L): 9·3, medium (M): 12·8 and high (H): 17·2 g histidine/kg diets), were fed to duplicate net pens in seawater. The experimental period was divided into three seasons

Effect of plant-based feed ingredients on osmoregulation in the Atlantic salmon lens

“…Certain changes in the deeper layers of the lens were, however, more frequently observed in P-lenses, although, the localisation of these changes suggests development at an early stage in the seawater phase. The findings of the present study are contrary to a recent feeding trial (Waagbø et al, 2004), where Atlantic salmon reared in sea water net pens and fed a diet containing the same lipid composition as in the present study developed severe cataracts. Under normal unregulated conditions in the sea, elevated or fluctuating water temperatures have been considered a risk factor for cataract development in farmed fish (Bjerkås et al, 2001).…”

“…In the study of Waagbø et al (2004), feeding plant oil based diets also resulted in elevated levels of linoleic and other n-6 acids in the lens and corresponded with in a massive increase in the incidence of Table 3). The standard error of the mean (SE) is shown by error bars.…”

“…In addition, a recent study has indicated a link between the use of vegetable oils in the feed and severe outbreaks of cataract in adult Atlantic salmon (Waagbø et al, 2004). However, in general, little effort has so far been made to investigate the consequences of the use of vegetable lipids and proteins in the diet on lens function and cataractogenesis in Atlantic salmon.…”

Criteria for Safe Use of Plant Ingredients in Diets for Aquacultured Fish

“…In a recent study it was demonstrated that dietary lipid sources affected cataract development in farmed Atlantic salmon adults in sea (Waagbø et al 2004). Fish fed a diet coated with a blend of plant oils (palm oil, linseed oil and rapeseed oil) grew equally from start-feeding and until 3 kg body weight, but developed more severe cataract than fish fed the same diet added marine oil.…”

Enhancing fish performance in aquaculture

“…This level is relatively easy to achieve in normal salmon feed formulations. However, juvenile Atlantic salmon require nearly twice as much histidine in their diet for a relatively short period after transfer from freshwater to seawater to prevent cataracts (Waagbø et al, 2010). Other nutrient requirement levels for fish can vary with feed formulation.…”