Canola meals (two commercial meals and one low‐heat meal) were processed to reduce fiber content, then washed with selected solvents to reduce the content of antinutritional substances and further concentrate protein. The meals, fiber‐reduced meals, and washed meals were used to provide 40% of total protein (26–38% of feed) in the diets of 6‐g rainbow trout for 3 weeks or 25% of total protein (21–31% of feed) in the diets of 23‐g chinook salmon for 11 weeks. Air‐desolventized (low‐heat) canola meal, as compared to commercial meal, provided no protein quality advantage in trout feeds. Fiber reduction processing of commercial meal increased meal protein content by 11–16% and reduced crude fiber by 23–50%, but did not have any effect on the quality of protein for trout or salmon. Solvent‐washing of fiber‐reduced meal improved fish response to canola meal, probably due to reduced glucosinolate content, but possibly also due to reduced sinapine content and alterations in protein availability. Protein concentration was increased by 25–40% by washing, and glucosinolate concentration was reduced by 40–90%.

Several artificial diets were tested for their ability to promote growth of gonads in the green sea urchin, Strongylocentrotus droebachiensis, over a 9-month period. Survival and test growth were also monitored, as were gonad lipid levels and water content (at the middle and end of the reproductive cycle only). The artificial diets differed in amount of protein and in the presence of various additives such as mannitol, algin, cholesterol, and β-carotene; a diet of air-dried kelp (Nereocystis luetkeana) was included for comparison. Survival was > 95% for all diets save a low-protein one (82% survival). Test diameters showed no significant change over time or among dietary treatments. All high-protein formulations produced significantly higher gonad indices than low-protein ones. Addition of β-carotene to the high-protein formulation significantly increased gonad growth relative to all other diets; this was especially noticeable in December, at the time of best market quality for the roe. Lipid levels were not significantly different among dietary treatments in either November or March, but did show a slight statistically significant rise between these months (21.4–22.7% dry mass). Water content also showed no significant difference among treatments, but was significantly higher in March (82% live weight), just prior to spawning, than in November (70%). Gonad indices for all artificial-diet formulations were higher than any previously recorded for S. droebachiensis.

Juvenile chinook salmon of three strains responded to inclusion of 28.7% of gelatinized starch in the diet with different degrees of reduction in growth rate and feed efficiency relative to control fish of the respective strains fed a low-starch, high-lipid diet of similar protein (46%) and estimated metabolizable energy content (16 mJ/kg). The productive protein value of the diet was not reduced to the same extent by the high intake of starch. Carcasses of fish fed the high-starch diet contained higher concentrations of protein and lower concentrations of lipid than control fish. The accumulation of liver glycogen in response to the high-starch diet differed among strains. Glucose tolerance curves also varied among strains but were poorly correlated with plasma concentrations of insulin. Tolerance to glucose loading was improved in fish previously fed the high-starch diet.

New Hampshire chicks utilized dietary fat more efficiently than did broiler-type or White Leghorn chicks. The difference was more pronounced with tallow than with corn oil. Utilization of fat by all three types of chicks increased until the chicks were about six weeks old. At hatching, the concentration of fatty acid binding protein (FABP) in the intestine of the broiler-type chicks was significantly less than in the New Hampshire and White Leghorn chicks. Concentration of FABP declined during the first 1 to 2 weeks of life and then increased. By four weeks of age the breed differences in concentration of FABP in the intestine were no longer apparent. At some time after four weeks of age, FABP reached maximum concentrations in the intestinal tissue of the chicks of different breeds and thereafter declined as a proportion of the total intestinal tissue. Broiler-type chicks, which did not utilize fat as efficiently as did New Hampshire chicks in the first weeks of life, displayed lower concentrations in the proximal third of the intestine and higher concentrations in the remainder of the intestine than was the case with the New Hampshire chicks. A high level of dietary fat or dietary supplementation with sodium taurocholate increased the concentration of FABP in the intestine.

The effect of artificial diets on the size and energy content of eggs and morphometry, survival, and metamorphic success of larvae was investigated in the green sea urchin, Strongylocentrotus droebachiensis, from the standpoint of developing a good broodstock diet for culturists. Groups of sea urchins were fed eight diets over a period of 9 months, then five of these dietary groups were selected for detailed larval-growth studies. The artificial diets differed in protein content and in various additives including mannitol, algin, cholesterol, and β-carotene; a diet of air-dried kelp was also included. Egg-energy content was highest on a high-protein diet with cholesterol and β-carotene additives, and the largest eggs so far recorded for the species (2.39 mm3 × 10−3) were produced on a high-protein diet with cholesterol additive. Larval survival to metamorphosis was >92% for all diets save for kelp (<5%). Kelp-fed adults also produced poorly metamorphosing larvae (<2%), suggesting that air-drying causes chemical changes in the kelp that are ultimately detrimental to larval health. Larval developmental rates were fastest on the high-protein β-carotene formulation. Larvae from this diet group also had the longest arms relative to body length, largest rudiment diameter, largest absolute and relative ciliated-band length (for efficient feeding), and had a high percentage of metamorphosis. These data suggest that a high-protein β-carotene diet will be useful for conditioning broodstock by prospective sea urchin culturists.