The effect of dietary
coconut oil on reproductive traits and egg fatty acid composition in rainbow
trout (Oncorhynchus mykiss)
R. Ballestrazzi, S. Rainis, F. Tulli, A. Bracelli-2003
Aquaculture
International, 11(3):
289-299
Abstract :
Two hundred and twenty rainbow trouts (IBW: 700 g)
were randomly allotted to four tanks, with a male/female ratio of 0.56. Fish
were fed for 168 d with four experimental diets containing herring oil, cod
liver oil and coconut oil with the following inclusion rates: diet A:
12-1-0% respectively; diet B: 6-1-6%; diet C: 0-1-12%; diet D: 0-0-13%.
Irrespective of the dietary treatment, weight gains of broodstocks were high
(> 3 g/d) and FCR below 2. No significant
difference was observed concerning the total amount of eggs spawn, egg
average weight (82.5 mg/egg) and lipid content (5.4 mg/egg). However, the
fatty acid profile of eggs was significantly affected by the dietary
treatments. The content of unsaturated fatty acids, particularly the n-3
fatty acid series (EPA and DHA) significantly decreased with increasing
levels of coconut oil in the diet.
(Dipartimento
di Scienze della Produzione Animale, Univ. degli Studi di Udine, Via S.Mauro
2, Pagnacco, 33010, Italy, e-mail: rodolfo.ballestrazzi@dspa.uniud.it)