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排序方式: 共有785条查询结果,搜索用时 109 毫秒
781.
Okamura Akihiro Yamada Yoshiaki Horie Noriyuki Mikawa Naomi Tsukamoto Katsumi 《Fisheries Science》2019,85(4):687-694
Fisheries Science - The efficiency of a new liquid-type diet for long-term rearing of Japanese eel larvae until metamorphosis was examined, as was the effect of diet viscosity on diet intake and on... 相似文献
782.
Hideaki Yamada 《Fisheries Science》2010,76(3):445-450
Age and growth during immature stages of the mangrove red snapper Lutjanus argentimaculatus were examined using 129 sectioned otoliths of fish collected in rivers and coastal areas around Ishigaki Island. Monthly changes in the marginal growth index indicated that ring marks (inner edge of opaque zone) are formed once a year around May. Estimated ages of the sampled fish ranged from 0.2 to 4.5 years. The proportion of mangrove red snappers collected in each sampling set in the rivers was associated with age, namely, the older the fish, the smaller the proportion. This result suggests that the mangrove red snapper gradually moves from the river habitat to coastal areas with increasing age between 1 and 3 years. The relationship between standard length (Y; cm) and age (X; year) was expressed by the linear regression Y = 6.30X + 5.41. Both the somatic and otolith growth of age-one and age-two fish collected in coastal areas were faster than those of fish collected in rivers, suggesting that individuals with fast growth leave the rivers earlier than those with slow growth. Whereas the basic growth pattern obtained in this study is similar to that of the mangrove red snapper in waters around Great Barrier Reef, Australia, there is a clear difference in length of time spent in rivers between the two populations, probably associated with the difference in the scale of the rivers used as nursery grounds. 相似文献
783.
Hideaki Yamada Masayuki Chimura Kimio Asami Taku Sato Masato Kobayashi Atsushi Nanami 《Fisheries Science》2009,75(5):1141-1146
Microstructures of lapilli were examined for reared larvae and juveniles of black-spot tuskfish Choerodon schoenleinii. Lapilli of larvae at 1 day after hatching have one diffuse and obscure ring with an otolith radius of 4.3 ± 0.50 μm (mean ± SD,
N = 8). The slope and intercept of the regression between the number of days after hatching and increment counts did not differ
significantly from one and zero, respectively, indicating that lapillus increments were formed on a daily basis after hatching.
There was an ontogenetic shift in the relative values of somatic and otolith growth, which corresponded to the transition
from pelagic larvae to settlement stage. Simultaneously, the daily increment width reached the maximum value. These findings
suggest that age at maximum value of increment width can be used as an indicator of the planktonic larval duration while settlement
mark is not found. Since ontogenetic shift in the relationship between otolith radius and body size was observed, back-calculation
of somatic growth in black-spot tuskfish using the otolith radius during the early life stages should be analyzed with caution,
and the method requires further validation. 相似文献
784.
Although emperors (Lethrinidae) are commercially important fisheries resources in tropical and subtropical waters, their home
range size and its spatial arrangement have not been sufficiently clarified. In the present study, the size and spatial arrangement
of the daytime home range of the thumbprint emperor Lethrinus harak were investigated by using a portable GPS receiver. In a 150 m × 200 m quadrat, 21 individuals of the species were identified
by their color pattern, and individuals were divided into four arbitrary size classes (class 1 < 20 cm TL ≤ class 2 < 25 cm
TL ≤ class 3 < 30 cm TL ≤ class 4). Fish tracking by snorkeling was conducted with the portable GPS receiver. Daytime site
fidelity of this species was high and there was a significant positive correlation between the home range size and fish total
length. Home ranges of same-sized individuals abutted each other (20.3% area overlap), whereas those of different-sized individuals
overlapped (48.3% area overlap). Agonistic behavior (attacking) occurred significantly more frequently between same-sized
individuals than between different-sized individuals. These results suggest that daytime home ranges of Lethrinus harak can be regarded as territories against same-sized individuals, but not different-sized individuals. 相似文献
785.
Maíra Harumi Higa Lage Júlia Augusta Rocha Pozavski Alysson Rodrigo Lamounier Eliane Gonçalves de Melo 《Anatomia, histologia, embryologia》2023,52(2):197-203
A bilateral patellar agenesis is an extremely rare congenital condition in which the patient does not develop both patellas and can present secondary alterations as bone, muscle and postural changes. There are some hypotheses that it has a genetic background presenting dominant characteristic. It is not yet standardized a gold treatment for this affection, but according to rare reports, clinical and surgical treatments are possible. This is a case report based on imagining exams of a mix breed male puppy that was born with bilateral patellar agenesis, an affection not yet reported in canine species. 相似文献