Results 171 to 180 of about 18,465 (208)

AUDIOMETRIC ASSESSMENT OF NORTHERN FUR SEALS, CALLORHINUS URSINUS

Marine Mammal Science, 1987
AbstractAerial and underwater audiograms for two young female northern fur seals (Callorhinus ursinus) and one young female California sea lion (Zalophus californianus) were obtained with the same procedure and apparatus. Callorhinus hears over a larger frequency range and is more sensitive to airborne sounds than Zalophus or any other pinniped thus ...
Patrick W. B. Moore, Ronald J. Schusterman   +1 more
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Reproduction in the female fur seal Callorhinus ursinus (Linn.)

2011
Gross and histological analyses of reproductive tracts from multiparous, nulliparous, and non-pregnant females of Pribilof Islands (eastern Pacific) origin have been used to determine the histology and physiology of the estrus cycle, the age of sexual maturity, and certain causes of prenatal mortality.
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Underwater audiogram of the northern fur seal (Callorhinus ursinus)

The Journal of the Acoustical Society of America, 1978
In order to compare the underwater hearing of otariid and phocid pinnipeds, two feral, yearling females were tested in a “go/no-go” response procedure. Using a tracking procedure, 20 runs was the minimum number of runs for each threshold estimate. Audiograms for both seals were similar in shape and absolute threshold values.
R. J. Schusterman, P. W. B. Moore
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Normal hematology and serum chemistry of northern fur seals (Callorhinus ursinus) in captivity

Zoo Biology, 2017
Northern fur seals (Callorhinus ursinus) are endemic to the North Pacific Ocean. They were hunted for their fur and became endangered in the late 1800s, but their populations recovered following the introduction of protection laws. Recently, populations have been decreasing again, although the reasons are unclear.
Kaoru Kohyama, Yasuo Inoshima
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[Spermatogenic cycle in seals (Callorhinus ursinus L.)].

Arkhiv anatomii, gistologii i embriologii, 1990
In the fur-seal germ cells at various stages of development are situated in the spermatic canaliculi as concentric layers in accordance with the stages of the spermatogenic cycle. By means of PAS-reaction 18 stages have been revealed in spermatogenesis of the fur-seal and basing on the first 15 of them, 15 stages of the spermatogenic cycles have been ...
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[Development of male germ cells in the fur seal (Callorhinus ursinus)].

Arkhiv anatomii, gistologii i embriologii, 1989
Three types of spermatogonia have been distinguished in the fur seal: type A, intermediate, type B. The type A spermatogonia are presented by means of five varieties: stem A, A1, A2, A3, A4. The spermatogonia of the stem A type is characterized with presence of equally distributed chromatin in the nucleus.
L Iu, Ashchepkova, V Ia, Fedoseev
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[Features of sleep in the water by the northern fur seal Callorhinus ursinus].

Zhurnal vysshei nervnoi deiatelnosti imeni I P Pavlova, 1987
The peculiarities of sleep in water and on land were investigated in four adult Northern fur seals (Callorhinus ursinus) of both sexes. The electrocorticogram of both hemispheres, the neck electromyogram, the electrooculogram and electrocardiogram were recorded with implanted electrodes.
O I, Liamin, L M, Mukhametov, I G, Poliakova   +2 more
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DENSITY DEPENDENCE IN NORTHERN FUR SEALS (CALLORHINUS URSINUS)

Marine Mammal Science, 1990
AbstractThis paper summarizes, updates, and interprets information on density‐dependent dynamics of populations of the northern fur seal (Callorhinus ursinus). Density‐dependent changes observed in these populations have involved various aspects of growth (body length, body weight, tooth weight, and size of other skeletal parts, especially the skull ...
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Migration of the Northern Fur Seal, Callorhinus ursinus

Journal of Mammalogy, 1953
Karl W. Kenyon, Ford Wilke
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Comparative anatomical and neurohistological observations on the tongue of the northern fur seal (Callorhinus ursinus)

The Anatomical Record, 1968
AbstractFive fetal and ten adult fur seal tongue were investigated. The number and shape of the vallate papillae vary from one to five on the different tongues. They are intermediate between the fungiform and circumvallate papillae in their neurohistological features. There are a few taste buds on the upper surface without a trench.
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