広島大学水畜産学部紀要 Volume 7 Issue 1
published_at 1967-07-31

走島の漁業 : Ⅲ. 小型底曳網漁獲物中の小型カニ類に関する研究(その1)小型カニ類を用いての低温期におけるクルマエビの飼育実験

Fisheries in Hashiri-shima : III. Studies on small-sized crabs found in catches of small trawlers part 1.
Murakami Yutaka
Onbe Takashi
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JFacFishAnim_7_77.pdf
Abstract
 小型機船底曳網の漁獲物中には,多くの未利用の底棲動物が含まれている.これらは漁獲後直ちに廃棄され全くかえりみられていない. これらの未利用資源の活用を目的として底曳網廃棄物中の小型カニ類と,アサリとを餌料として用いたクルマエビの飼育実験を行なった.実験期間は秋季→冬期の低温時期(10月下旬-12月下旬)の2ヶ月間である.
 アサリ投与群と,アサリ,カニ混合投与群の成長を比較した結果,後者の方がやや成績が良好であった.脱皮個体は何れの群においても水温15℃以上のときにのみ観察された.
 摂餌量の日変動は著るしいが, 10日毎の測定結果よりみると, 日間摂餌率と水温との聞には正の相関が認められた.すなわち,水温12℃ では,日間摂餌李は2%付近の低い値であるが, 16-17℃ を境として,その急激な増加がみられた.
 また,日間摂餌率と増重率とを対比させてみると,同様な正の相関関係が認められた. この関係から,クルマエビの体重維持lこ必要な餌料量は,体重の2-3% にあたることがわかった.
 アサリ,カニ混合投与群におけるクルマエビは,それぞれの餌の混合比率に応じて摂餌することが明らかとなり,この2様類の餌料lこ関する限りでは,摂餌における餌の選択性はあまり認められなかった.
Abstract
Many useless benthic animals are contained in the catches of small trawlers. Small crabs are one of these unutilized resources. Attempt was made to use these animals as food in rearing of the Kuruma prawn, Penaeus japonicus BATE. The experiment was carried out using these small crabs and clam meat during low-temperature season from late October to late December, 1964.

Comparison of the growth between the two groups fed on clam meat only and on the mixture of clam and crabs, respectively, clarified that the latter group grew more rapidly than the former. Molting was observed only at temperatures above 15°C. in both groups.

A positive correlation was shown between the feeding rate per day and the mean temperature of 10-day period; namely, at 12°C., the feeding rate was as low as about 2%, and with the elevation of temperature, especially above 16-17°C., increased remarkably.

Furthermore, the correlation between the feeding rate per day and the growth rate was also positive, revealing that the daily ration necessary for the maintenance of body might be 2-3 % of the body weight.

The prawn fed with the mixture of clam and crab meat took the two kinds of food in approximately the same clam/crab ratio as was given. This fact seems to show that in the feeding of the prawn there is no selectivity as to the two kinds of food.