异育银鲫的蛋白质消化率研究

研究了异育银鲫对饲料蛋白质的消化率，及其在不同蛋白质含量、不同水温和不同体长条件下的变化。结果表明：１．饲料蛋白含量在２８－５２％范围内，鲫鱼对蛋白质的消化率与饲料中的蛋白质含量呈显著正相关。２．水温为２５℃时，蛋白质的消化率最高，水温在３５℃时，尽管粪便较多，浓缩率也高，但因消化酶活性降低，导致粪蛋白含量明显偏高；３．体长为６ｃｍ以下的异育银鲫蛋白质消化率明显偏低。据推测，６ｃｍ体长组鱼的消化机

The study of protein digestibility of gynogenetic grucian carp

This paper deal with the protein digestibility of gynogenetic crucian carp andits changes in different protein levels, water temperatures and body length. The resultsshowed: (1 )There was a positive linear relation between dietary protein level and proteindigestibility of the fish. (2)The velue of protein digestibility was the biggest when watertemperature was 25 C. But when water temperature rose up to 35C the percent of protein inexcrement was the biggest because of lower level of digestive ferment active in spite of richexcrement and high ratio of excrement concentration at this point. (3)Protein digestibilitywas much lower in the group of body length below 6 cm than in other groups. Based on thegroup below 6 cm was not perfect. This was caused by the structure of alimentary canal wallwhich did not develop perfectly, not by the factor of digestive ferment active. Thedigestibility of the fish whose body length was above 7 cm only changed in the small region.