Study On Nutrition And Attractant Of Euphausia

Euphausia pacific is widely distributed over the Shandong Peninsula and the central andnorthern regions of Yellow Sea, and has abundant resources. The contents of crude protein inEuphausia Pacific is as much as imported fishmeal to65%, but Euphausia Pacific is cheaperthan imported fishmeal. In our country, Euphausia Pacific is usually used as feed additive, butthe raw krill can not be fully utilized. After hydrolyzed Euphausia Pacific adding to the feed,the feed will have a better taste and increase the appetite of aquatic animals.Firstly, the nutrient components of pacific krill was studying. We made the evaluationthat on amino acid composition and contents of pacific krill powder by using two differentmodels of amino acid assessment standards. The results showed that the contents of crudeprotein, crude fat, crude ash, moisture of pacific krill powder were64.44%,14.95%,10.22%and4.98%respectively. We found18common amino acids that reached to70.69%in pacifickrill powder. The content of essential amino acids was36.06%, the percentage of essentialamino acids in total amino acids was52.01%. The essential amino acids index is48.35(EAAI),which was comply with the FAD/WHO. In pacific krill, the content of delicious amino acidsis21.28%, making up30.10%of total amino acids. The contents of trace element wereabundant, especially the content of Se can reach to0.4mg/100kg dry wet. The average valuesof main heavy metals were lower than the relative standard in feed. As a result, we considerEuphausia Pacific is one kind of krill with high nutritional value, which deserves exploitationand utilization.Secondly, author used cryprinus carpiod which has a beauty surface as the object forresearching, used hydrolyzed pacific krill powder as the attractant and used ball method as theexperimental method. The result showed that at the pH is6.5, the time is4h, the solid-liquidratio is1:3, the enzyme concentration is1500U/g and the temperature is50℃, the attractantis the best.Thirdly, there are two kinds of ball method. One method is counting the fish touch theball within5min, another is counting the the time(s) that the fish touch the ball take. To makea comparison for the two methods, we selected growth method to evaluate. The result showedthe first one is better.Finally, we evaluate the enzyme-hydrolysate of Euphausia pacific. The product was akind of light yellow powder which was soluble in water and had shrimp flavor. The productcould absorb water quickly but moisture retention ability was low relatively. The rate of fatoxidation and protein hydrolyzate of the product are lower than domestic and importedfishmeal. Therefore, the product is a good storage protein feed.Furthermore, the hydrolyzateis useful to carp and tilapia.