Yasuo Yone

Fatty acid composition and dietary value of rotifer Brachionus plicatilis fed on waste lipid treated with Aspergillus terreus

Attempts were made to improve the dietary value of rotifer fed on bakers yeast by direct feeding of microbial-treated lipid. The nontreated lipid (NTL) from mackerel waste juice was treated with Aspergillus terreus, and the treated lipid (TL), NTL and pollack liver oil (PLO) were emulsified with sea water and proteinous sediment from the waste juice. The emulsified lipids and yeast were fed to rotifers and the proximate and fatty acid compositions of the rotifers were determined. Furthermore, ayu larvae were reared with the rotifers fed on bakers yeast (BY) with or without TL or NTL, and their growth and survival rate were compared. The rotifers fed on the lipids showed similarly higher lipid content than the initial rotifer. However, the ω3 HUFA content of rotifer fed on TL (BY+TL rotifer) was higher than that of the rotifer fed on NTL (BY+NTL rotifer) and similar to rotifer fed on PLO (BY+PLO rotifer). The total body length of larvae reared with BY+NTL rotifer (BY+NTL group) was significantly inferior to that of BY+TL group at the end of the 25 days feeding trial.The survival rates of BY+NTL group in feeding trial and handling tests were also lower than those of BY+TL group. The larvae reared with rotifer fed on BY only were the lowest of all the groups in the growth and survival rate.

Microbial treatment of liquid from mackerel waste juice

Yeast Saccharomyces cerevisiae IFO 2114 was cultured in 25l of 75% sea water containing liquid obtained from mackerel waste juice and molasses (WY) for 48h, and (1) nitrogen and pho-sphorus contents in WY medium and (2) proximate and fatty acid compositions of the harvested yeast (WY yeast) were determined. The amount of harvested WY yeast was sufficient to feed rotifers (150×106 indiv./ton) for a day. Furthermore, the yeast reduced nitrogen and phosphorus contents in the medium to a level which was considered to be safe to discard. On the other hand, WY yeast was higher than yeast cultured in MY medium and bakers yeast and far lower than ω yeast and marine chlorella in lipid content and percentage of ω3 HUFA in total fatty acids.

Studies on Utilization of Trimmings Wasted in Manufacturing “Kamaboko”, a Cooked Fish Cake-IV

In all the experiments on egg production which have hitherto been carried out1-3), use was made of rather small number of hens and of the battery house. The present study has been carried out on one-year old hen without using the battery house and under conditions as practical as possible. The results obtained can be summarized as follows: 1. The supplementation of the solubilized trimmings at a 5% dry basis level gave more egg production as compared with that of fish meal at a 10 per cent level. 2. The partial replacement of the fresh trimmings with the solubilized trimmings yielded more or less a favorable effect on egg production. 3. The supplementation of the solubilized trimmings at a 2.5 per cent dry basis level gave egg production similar to the control group, while a little increase was observed from July to September.

Studies on Utilization of Trimmings Wasted in Manufacturing Cooked Fish Paste-III

Chicks fed a diet supplemented with the solubilized trimmings at a 2 or 3 per cent dry basis level for 8 to 32 weeks showed a significant growth response, (Table 1 and 2). The difference in body weight between the chicks fed the solubilized trimmings and the control chicks fed only all-vegetable protein ration was significant at a 5% level (Table 1). It is to be noted that earlier start of egg production has been found in the experimental group (Table 2). It has been shown that chicks which were raised on the ground without using battery-house gave an increase of 14 per cent in the growth rate after 9 weeks by feeding an all-vegetable protein ration with the solubilized trimmings at a 3 per cent level (Table 3).