ISSN:
1365-2109
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
A study was conducted to determine growth and feed utilization by haddock fed diets containing graded levels of protein (35, 40, 45 and 50%). Haddock fingerlings with an average weight of 24 g were hand-fed one of the four isoenergetic (≈16.6 MJ digestible energy kg−1) experimental diets to satiation, three times a day during the 9-week period. Filtered and UV-treated water (salinity, 30‰) was supplied to each circular tank (holding capacity: 320 L) at 4 L min−1 in a flow-through system. Increases in dietary protein improved weight gain, specific growth rate (SGR) and feed : gain ratio. The highest weight gain (percentage/initial weight) was observed in fish fed 50% protein, although there was no significant difference between groups fed 45% and 50% protein. A similar effect was observed in SGR of fish fed 50% protein, which was the highest among treatments. Although an increase in dietary protein resulted in a slight increase in feed intake, the lowest feed : gain ratio was obtained in fish fed the diet with the highest protein. Nitrogen intake increased from 1.48 to 2.33 g with the increase in dietary protein levels, which resulted in an improvement in whole-body nitrogen gain, although there were no significant differences in nitrogen retention and protein efficiency ratio among fish groups. The broken-line regression of weight gain against protein level yielded an estimated protein requirement of 49.9%.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1355-557x.2001.00001.x
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