Kasamatsu Masahiko, Hasegawa Kazuhiro, Wakabayashi Ikuo, Furuta Masami, Inoue Hiroki, Iwano Hidetomo
Marine Biological Laboratory, Toba Aquarium, Toba, Japan.
Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido, Japan.
PLoS One. 2025 Jan 30;20(1):e0288891. doi: 10.1371/journal.pone.0288891. eCollection 2025.
Hand-rearing of marine mammals is an essential technique for the husbandry of orphans in captivity or the wild, especially endangered cetacean species. The purpose of the present study was to establish a method for successful hand-rearing and evaluate the nutritional state of neonatal finless porpoises. Two neonate finless porpoises maternally neglected at 5 days of age (Day 5) (neonate A, animal A) and Day 4 (neonate B, animal B) were hand reared. The amount of each tube feeding and daily number of nursings for animals A and B during the lactation period were gradually increased to 1,355 and 1,120 ml and 16 and 14 times, respectively. The mean daily caloric intake during the lactation period and average increase in body weight of animals A and B were 2,048 ± 207 and 2,206 ± 169 kcal and 65.4 and 66.9 g/day, respectively. Hypoproteinemia and hypertriglyceridemia were observed in the two neonates during the early stage of hand-rearing. The plasma concentrations of 24 free amino acids in the neonatal porpoises were significantly higher compared with adult porpoises. Plasma valine, leucine, and isoleucine levels in the neonates were dramatically higher than those in adults. Hyperlipoproteinemia, characterized by a higher percentage of very-low-density lipoprotein and the appearance of midband, was also observed in the two neonates, along with hypertriglyceridemia. A hand-rearing method for finless porpoises was successfully established in this research. Nutritional evaluation of serum protein, free amino acids, and lipid components is needed to improve the survivability of hand-reared neonatal porpoises. The hand-rearing method established in the present study is an essential technique for the husbandry of finless porpoises and can be applied to the conservation of other members of the porpoise family, including vaquita and Yangtze finless porpoises, which are the most endangered dolphins in the world.
人工饲养海洋哺乳动物是圈养或野外孤儿（尤其是濒危鲸类物种）饲养管理的一项重要技术。本研究的目的是建立一种成功人工饲养的方法，并评估新生江豚的营养状况。对两头分别在出生第5天（新生A，动物A）和第4天（新生B，动物B）被母亲遗弃的新生江豚进行人工饲养。哺乳期动物A和B每次管饲的量和每日哺乳次数分别逐渐增加到1355毫升和1120毫升，以及16次和14次。哺乳期动物A和B的平均每日热量摄入分别为2048±207千卡和2206±169千卡，体重平均每日增加分别为65.4克和66.9克。在人工饲养的早期阶段，这两头新生江豚出现了低蛋白血症和高甘油三酯血症。与成年江豚相比，新生江豚血浆中24种游离氨基酸的浓度显著更高。新生江豚血浆中的缬氨酸、亮氨酸和异亮氨酸水平显著高于成年江豚。这两头新生江豚还出现了以极低密度脂蛋白百分比升高和中带出现为特征的高脂蛋白血症以及高甘油三酯血症。本研究成功建立了江豚的人工饲养方法。需要对血清蛋白、游离氨基酸和脂质成分进行营养评估，以提高人工饲养新生江豚的存活率。本研究建立的人工饲养方法是江豚饲养管理的一项重要技术，可应用于保护鼠海豚科的其他成员，包括小头鼠海豚和长江江豚，它们是世界上最濒危的海豚。
