灯光诱饵技术对深水网箱养殖鱼类品质的影响

Effect of Light Trapping Technology on Fish Quality in Deep Water Cage Fish Culture

关键词:  灯光诱饵系统  深水网箱  鱼类  脂肪  脂肪酸  氨基酸

Key words:  Light trapping system  Deep water cage  Fish  Fat  Fatty acid  Amino acid

摘要:

为评估太阳能灯光诱饵技术在深水网箱养殖鱼类品质改善方面的应用效果，本研究在青岛金沙滩海域的深水网箱中设计并安装太阳能灯光诱饵设备，通过“灯光诱饵”吸引活体饵料聚集于网箱内，从而为实验大黄鱼(Pseudosciaena crocea)、鲈鱼(Lateolabrax japonicus)和真鲷(Pagrus major)提供天然饵料，全程无人工投饵，使其在自然状态下，拟半野生化养殖至上市。大黄鱼、鲈鱼和真鲷经过5个月的实验网箱及传统网箱养殖后，通过测定其脂肪、脂肪酸和氨基酸含量判断其品质。结果显示，在安装灯光诱饵设备的影响下，网箱养殖大黄鱼、鲈鱼和真鲷的感官性状显著好于传统网箱养殖鱼类，11月3种鱼体肥满度比6月均显著下降(P<0.05)。灯光诱饵网箱养殖大黄鱼和真鲷肌肉内粗脂肪含量分别比传统网箱养殖低75.24%和46.81%，差异极显著(P<0.01)，鲈鱼差异不显著(P>0.05)。灯光诱饵网箱养殖大黄鱼、鲈鱼和真鲷肌肉内DHA含量高于传统网箱养殖鱼类，差异极显著(P<0.01)；总脂肪酸含量、棕榈酸含量低于传统网箱养殖鱼类，差异极显著(P<0.01)。灯光诱饵网箱养殖的3种鱼的肌肉内的呈味氨基酸、呈鲜味氨基酸、呈甘味氨基酸、总氨基酸和非必需氨基酸含量均升高，其中大黄鱼变化最显著，实验组比对照组的呈味氨基酸、呈鲜味氨基酸和呈甘味氨基酸含量分别高11.78%、9.17%和19.57%，差异显著(P<0.05)。研究表明，太阳能灯光诱饵深水网箱养鱼技术虽然降低了养殖鱼类的生长速度，但可以改善养殖鱼类品质，且养殖投入明显降低，养殖收入显著提高，该方法可显著提升产出效益，因此，可作为一种绿色健康养殖模式进行推广应用。

Abstract:

To study the influence of light trapping technology on the quality of fishes cultured in deep-water cages, light trapping equipment was designed and installed in deep-water cages in Qingdao. Light trapping equipment involves green LED light (wavelength 525~530 nm) installed on the cage to attract live prey in the sea, providing natural food for the cultured fishes inside the cage. In this study, three important fish species were selected: Pseudosciaena crocea, Lateolabrax japonicus, and Pagrosomus major. Since there were no artificial feedings throughout the culture period, the fishes are in a semi-wild growth state. The quality of the cultured fish was determined by measuring the fat, fatty acid, and amino acid content of the specimens in the treatment cages (equipped with light trapping equipment) and traditional cages (with artificial feedings and without light trapping equipment) after a 5-months’ culture period. The results showed that the sensory characteristics of P. crocea, L. japonicus, and P. major in the treatment cages were significantly better than the fishes in traditional cages. The body fat of the three fishes cultured by light trapping technology were significantly lower than those of the control groups (P<0.05). The crude fat contents in the muscles of P. crocea and P. major cultured in treatment cages was 75.24% and 46.81%, which were significant lower than those of traditional cage culture fishes (P<0.01). There was no significant difference in the crude fat content in the muscle of L. japonicus (P>0.05). The docosahexaenoic acid content in the muscles of P. crocea, L. japonicus, and P. major in treatment cages were extremely significant higher than those in fishes cultured in traditional cages (P<0.01). Moreover, the total fatty acid content and palmitic acid content were significantly lower than those in fishes cultured in traditional cages (P<0.01). Under the influence of light trapping equipment, the indices including the contents of taste amino acids, umami amino acids, sweet amino acids, total amino acids, and non-essential amino acids in the muscles of the three fish species in the treatment group were significantly higher than those of the traditional groups (P<0.05). And the contents of flavored amino acids, umami flavored amino acids and sweet flavored amino acids in P. crocea in the treatment groups increased 11.78%, 9.17%, and 19.57% than those in traditional groups. Moreover, the difference was significant. All the results show that although the deep-water net cage fish culture technology with light trapping reduces the growth rate of cultured fish, but it can improve the fish quality and increase output efficiency. The system could be used to promote and apply a green and healthy aquaculture model.