Showing papers on "Fish oil published in 1979"

Effects of Dietary Lipids on Fatty Acid Composition of Channel Catfish Fry

Abstract: Channel catfish (Ictalurus punctatus) fry were reared in flow-through troughs and circular tanks on practical diets supplemented with fish oil, soybean oil, or beef tallow. A control diet was also utilized which contained beef tallow at a reduced level. Fry reared on the fish oil diet increased in weight significantly more than fish fed the soybean oil and control diets. Survival was relatively poor because of water quality problems. Fry reared on the beef tallow diet exhibited poor growth and survival due to an Ichthyophthirius multifilis infestation and generally poor fish condition. Proximate analyses showed that body compositions among the four treatment groups were similar. In general, fatty acid compositions of the fry reflected dietary levels. Fry fed the fish oil diet contained high levels of linolenic family fatty acids, while fry reared on the soybean oil diet showed high carcass levels of linoleic family fatty acids. Fry reared on the beef tallow and control diets were intermediate in ...

魚介類種苗生産用酵母(油脂酵母)の開発

Abstract: A new kind of yeast was developed as a culture medium for rotifer Brachionus plicatilis in order to improve the dietary value of rotifers cultured with baker's yeast Saccharomyces cerevisiae for fish larvae. This new type of yeast (designated as ω-Yeast) was produced by adding fish oil or cuttlefish liver oil as a supplement to the culture medium of baker's yeast, resulting in a high content of lipid and ω3 highly unsaturated fatty acids (ω3 HUFA), the essential fatty acids for marine fish. The rotifers cultured with ω-Yeast were high in the lipid content, in general, together with ω3 HUFA, as a result of the oils added to the baker's yeast. The incorporation of ω3 HUFA from ω-Yeast was observed to reach a maximum at around 12h-feeding. Furthermore, the dietary value of the rotifers to fish larvae was found to be significantly improved, comparable to that of the rotifers cultured with marine chlorella Chlorella minutissima. These results clearly indicate that the newly developed yeast has superior food value for rotifers, one of the most important living feeds used in the production of fish seed.

Comparison of lipid status in the hearts of piglets and rats on short term feeding of marine oils and rapeseed oils

Abstract: A series of 4 experiments with piglets and one experiment with rats has been conducted to establish the cardiac lipid status of weanling (3 weeks old) male animals fed fats with different contents of docosenoic fatty acids. Experimental fats were rapeseed oil (RSO) (48.0% 22:1), refined fish oil (RFO) (14.6% 22:1), partially hydrogenated fish oil (PHFO) (14.3% 22:1) and lard (0% 22:1) combined with sunflower seed oil (SFO) in different proportions in diets with 21% total fat. Lipidosis could not be detected in piglets as increased heart weights, by chemical assay for myocardial contents of triglycerides, or by accumulation of docosenoic fatty acids or nonesterified fatty acids (NEFA). In rats, diets with RSO at a level of 16% increased myocardial triglyceride and docosenoic fatty acid contents about 7 times while the effect on cardiac NEFA was inconsistent. Histological examinations of the hearts revealed stainable intracellular fat droplets in some piglets fed 16% RSO for 8 to 13 days, but not after 2, 4 and 6 and 16, 19 and 22 days of feeding. After 10 days of feeding, mild to moderate histological lipidosis was found in piglets fed diets containing 2% or more of 22:1 fatty acids, with no significant difference between RSO, RFO and PHFO in this respect. The same diets in rats gave about 5 times more histological lipidosis than in piglets. This is attributed to a difference in species response, the rat reacting in a more pronounced manner than the piglet. The cardiac lipidosis no-effect level in piglets corresponded to a daily intake of docosenoic fatty acids of 0.4 g per kg body weight. Mild lipidosis was also found in a few animals on docosenoic acid-free diets.

Marine‐derived fatty acids of fish oils as raw materials for fatty acids manufacture

Abstract: Fish oils, often an abundant source of C20 and C22 fatty acids, could supplement rapessed oil in the manufacture of long chain saturated fatty acids. Herring oil, traditionally the fish oil of choice, is in very short supply due to depletion of fishery stocks. Menhaden oil, when made from fish caught in the Atlantic, could furnish a steady supply with long chain acids at about the 30% level. Oil made from other species such as anchovy or pilchard need further data on fatty acid content and variability. Manufacture of polyunsaturated fatty acids from fish oils is hampered by lack of suitable procedures. Potential markets for fish oil polyunsaturates especially in the pharmaceutical field seem promising.

Extreme pressure additive

Abstract: PURPOSE:To obtain an extreme pressure additive capable of exhibiting improved properties in lowering friction and preventing seizure between metals, by hydrogenating an ester of fish oil fatty acid, followed by chlorination.