Kentaro Q. Sakamoto
University of Tokyo
GeneInternal medicineEndocrinologyGene expressionMolecular biologyForagingChemistryEcologyOral administrationTakeoffHeart rateFlappingThalassarche melanophrysLarus crassirostrisLeptonychotes weddelliiEnvironmental scienceNitric oxideCytochrome P450BiochemistryCYP1A2BiologyZoologyWingPharmacology
Publications 49
#1Masaru NaruokaH-Index: 3
#2Yusuke GotoH-Index: 6
Last. Katsufumi SatoH-Index: 48
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#1Chihiro Kanno (Hokkaido University)H-Index: 8
#2Kentaro Q. Sakamoto (Hokkaido University)H-Index: 16
Last. Masashi Nagano (Hokkaido University)H-Index: 19
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: In the present study, bull sperm in the first and second ejaculates were divided into subpopulations based on their motility characteristics using a cluster analysis of data from computer-assisted sperm motility analysis (CASA). Semen samples were collected from 4 Japanese black bulls. Data from 9,228 motile sperm were classified into 4 clusters; 1) very rapid and progressively motile sperm, 2) rapid and circularly motile sperm with widely moving heads, 3) moderately motile sperm with heads mo...
6 CitationsSource
#1Saori Yano (Hokkaido University)H-Index: 2
#2Kentaro Q. Sakamoto (Hokkaido University)H-Index: 16
Last. Yoshiaki Habara (Hokkaido University)H-Index: 16
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Inbreeding avoidance is essential to providing offspring with genetic diversity. Females' mate choice is more crucial than males' for successful reproduction because of the high cost of producing gametes and limited chances to mate. However, the mechanism of female inbreeding avoidance is still unclear. To elucidate the mechanism underlying inbreeding avoidance by females, we conducted Y-maze behavioral assays using BALB/c and C57BL/6 female mice. In both strains, the avoidance of male urine fro...
2 CitationsSource
#5Phil N. Trathan (NERC: Natural Environment Research Council)
The foraging strategy of many animals is thought to be determined by their past experiences. However, few empirical studies have investigated whether this is true in diving animals. We recorded three-dimensional movements and mouth-opening events from three Antarctic fur seals during their foraging trips to examine how they adapt their behaviour based on past experience—continuing to search for prey in the same area or moving to search in a different place. Each dive cycle was divided into a tra...
8 CitationsSource
Reproductive investment during the chick-rearing period is an important contributor to lifetime fitness. Key to chick-rearing is the success of parental foraging, as food deliveries affect chick growth and survival up until fledging. For seabirds, oceanographic conditions including factors such as sea surface temperature are known to influence foraging decisions, but few studies have examined the physiological variables that might affect those decisions. We used global positioning systems (GPS),...
8 CitationsSource
#1M. Habibur Rahman (Ehime University)H-Index: 13
#2Kentaro Q. Sakamoto (Hokkaido University)H-Index: 16
Last. Satoru Suzuki (Ehime University)H-Index: 34
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Antibiotic-resistant bacteria can be detected in pristine environments and animals. Tetracycline (TC) is frequently used for wide areas of veterinary medicine, which selects TC-resistant bacteria. The TC resistance genes are known from natural environments, and tet(M) is the broadest host range tet gene. Here, we report that TC-resistant bacteria and the TC resistance gene tet(M) were diverse in Adelie penguin intestines, even within a single penguin colony. Total bacterial counts were as high a...
13 CitationsSource
#1Brian C. BattaileH-Index: 9
#2Kentaro Q. SakamotoH-Index: 16
Last. Andrew W. TritesH-Index: 60
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#1Brian C. Battaile (UBC: University of British Columbia)H-Index: 9
#2Kentaro Q. Sakamoto (Hokkaido University)H-Index: 16
Last. Andrew W. Trites (UBC: University of British Columbia)H-Index: 60
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We tagged 82 lactating northern fur seals (Callorhinus ursinus) with tri-axial accelerometers and magnetometers on two eastern Bering Sea islands (Bogoslof and St. Paul) with contrasting population trajectories. Using depth data, accelerometer data and spectral analysis we classified time spent diving (30%), resting (~7%), shaking and grooming their pelage (9%), swimming in the prone position (~10%) and two types of previously undocumented rolling behavior (29%), with the remaining time (~15%) u...
14 CitationsSource
#1Hazuki MizukawaH-Index: 20
#2Yoshinori IkenakaH-Index: 28
Last. Mayumi Ishizuka (Hokkaido University)H-Index: 34
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Contamination levels of coplanar polychlorinated biphenyls (Co-PCBs), polycyclic aromatic hydrocarbons (PAHs), and dichlorodiphenyltrichloroethane (DDTs) were measured in the entire body of the large Japanese field mouse (Apodemus speciosus) collected from Hokkaido (Ishikari and Rankoshi) and Aomori prefecture (Takko) in Japan. Higher concentrations of PCBs including Co-PCBs, were observed in the mice collected from Ishikari than those from Rankoshi. The concentration of PAHs in the soil from Is...
1 Citations