scholarly journals Trapped river otters (Lontra canadensis) from central Saskatchewan differ in total and organic mercury concentrations by sex and geographic location

FACETS ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 139-154 ◽  
Author(s):  
Steven C. Wilkie ◽  
Richard H.M. Espie ◽  
Niladri Basu ◽  
Karsten Liber ◽  
Britt D. Hall
Keyword(s):  
Kidney Tissue ◽  
Geographic Location ◽  
Geographic Area ◽  
Lontra Canadensis ◽  
Noninvasive Method ◽  
Fresh Weight ◽  
Organic Mercury ◽  
River Otters ◽  
Liver And Kidney ◽  
Boreal Shield

Mercury (Hg) in wildlife remains of great concern, especially for apex piscivores. Despite this, exposure information from many species in many areas is lacking, so that management decisions are hampered. Here we examine Hg concentrations in fur, liver, and kidney tissues from river otters ( Lontra canadensis (Schreber, 1777)) ( n = 203) to quantify existing Hg concentrations over a broad geographic area in Saskatchewan. Mean fur total Hg (THg) (9.68 ± 7.52 mg/kg fresh weight (f.w.)) was significantly correlated with THg and organic Hg (OHg) in liver and kidney tissue, showcasing the potential for using fur as a noninvasive method of monitoring Hg in top-level mammals. Livers of males had higher mean OHg concentrations than livers of females (males: 2.71 mg/kg d.w., females: 1.87 mg/kg d.w.), but not significantly so. No sex-related differences were observed in kidney OHg concentrations. THg concentrations in otter fur collected in the Boreal Shield ecozone (Churchill River Upland) were significantly higher (mean = 16.1 mg/kg f.w.) than in otter fur collected from the Boreal Plain ecozone (mean = 8.59 mg/kg f.w.). Fur from otters ( n = 20; trapping block N66) trapped near a decommissioned smelter contained the highest concentrations of THg in the study (mean = 18.4 mg/kg f.w.).

Spacing, movements, and habitat selection of the river otter in boreal Alberta

1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero
Keyword(s):  
Lontra Canadensis ◽  
Home Ranges ◽  
Adult Males ◽  
Movement Rates ◽  
River Otters ◽  
Aquatic Mammal ◽  
Adult Females ◽  
Two Factors ◽  
Bog Lakes ◽  
Selection Of

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.

Development of polymorphic microsatellite loci for North American river otters (Lontra canadensis) and amplification in related Mustelids

2003 ◽  
Vol 4 (1) ◽  
pp. 56-58 ◽  
Author(s):  
Amanda S. Beheler ◽  
Jennifer A. Fike ◽  
Lisa M. Murfitt ◽  
Olin E. Rhodes ◽  
Thomas S. Serfass
Keyword(s):  
North American ◽  
Microsatellite Loci ◽  
Lontra Canadensis ◽  
River Otters ◽  
American River ◽  
Polymorphic Microsatellite

HORMONAL EFFECTS ON LIVER AND KIDNEY CYTOPLASM

1956 ◽  
Vol 13 (3) ◽  
pp. 319-329 ◽  
Author(s):  
E. REID
Keyword(s):  
Sucrose Solution ◽  
Kidney Tissue ◽  
Mitochondrial Fraction ◽  
Supernatant Fraction ◽  
Phospholipid Content ◽  
Hormonal Status ◽  
Hormonal Effects ◽  
Liver And Kidney ◽  
Hypophysectomized Rats ◽  
Microsome Fraction

SUMMARY 1. Differential centrifugation, in 0·25 m sucrose solution, has been performed with rat liver and kidney tissue to ascertain whether the yield and composition of the cytoplasmic fractions (mitochondrial, microsome and supernatant fractions) depend on the hormonal status of the animal. 2. After hypophysectomy the ribonucleic acid (RNA) of the mitochondrial fraction from liver underwent a decrease (in terms of body weight) which was sufficient to account for the fall in the RNA of the liver as a whole. There was also a decrease in the yield of the mitochondrial fraction. Administration of pituitary growth hormone (GH) to hypophysectomized rats not only restored to normal the amount of RNA in the mitochondrial fraction and the yield of that fraction, but also led to an apparent shift of RNA from the microsome fraction to the supernatant fraction. A further change observed after hypophysectomy, whether or not GH had been given, was a rise in the yield of the microsome fraction. Hypophysectomized rats given thyrotrophin (TSH) did not show significant cytoplasmic changes as found with untreated hypophysectomized rats, but it was not possible to conclude that TSH had actually reversed the effects of hypophysectomy. 3. Castrated rats showed no abnormalities in the yields of the liver cytoplasmic fractions or in the concentration of RNA in the fractions. Alloxan-diabetic rats showed a rise in the yield of the supernatant fraction from liver. 4. Untreated adrenalectomized rats showed a rise in liver deoxyribonucleic acid, a fall in the yield of the liver mitochondrial fraction, but not in the amount of RNA in that fraction, and a rise in the amount of RNA in the supernatant fraction. Replacement therapy with various adrenocorticoids was attempted, with only partial success. 5. In contrast with the RNA content, the phospholipid content of the liver cytoplasmic fractions was not, in general, dependent on hormonal status. 6. Determinations of the yield and composition (RNA and phospholipid) of the cytoplasmic fractions from kidney disclosed certain hormonal effects, differing from those observed with liver; for example, the kidneys from hypophysectomized rats furnished microsome fractions in lowered yield but with an increased concentration of RNA.

scholarly journals Efficacy of Caffeic Acid on Diabetes and Its Complications in the Mouse

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3262
Author(s):  
Nada Oršolić ◽  
Damir Sirovina ◽  
Dyana Odeh ◽  
Goran Gajski ◽  
Vedran Balta ◽  
...  
Keyword(s):  
Lipid Profile ◽  
Caffeic Acid ◽  
Fasting Blood Glucose ◽  
Kidney Tissue ◽  
Serum Glucose ◽  
The Body ◽  
Diabetic Mice ◽  
Atherogenic Indices ◽  
Liver And Kidney ◽  
Hematological And Biochemical Parameters

Diabetic dyslipidemia and hyperglycemia contribute to excessive reactive oxygen species (ROS) production, leading to deleterious complications, such as nephropathy, atherosclerosis and cardiac dysfunction, and target major organs in the body. The aim of this study was to investigate the effect of caffeic acid (CA) on mouse weight and survival, serum level of fasting blood glucose (FBG), serum lipid parameters and atherogenic indices, oxidative damage in blood, liver and kidney tissue, pathophysiological changes and their function markers in healthy and alloxan-induced type 1 diabetic mice. Diabetes was induced in mice with a single intravenous injection of alloxan (75 mg kg−1). Two days later, CA (50 mg kg−1) was given intraperitoneally for seven days in diabetic mice. Diabetes affected glucose level, lipid profile, hematological and biochemical parameters, induced DNA damage and apoptotic/necrotic death in whole blood cells, liver and kidney, leading to weight loss and a decreased lifespan. CA treatment of diabetic mice revealed a protective effect on the liver and kidney, hypoglycemic and hypolipidemic properties and high protection against atherogenic outcomes. The obtained results suggest that CA is a safe and potent agent against diabetes that acts as an effective antioxidant in reducing serum glucose, lipid profile and atherogenic indices, leading to increased lifespan in mice.

scholarly journals A River Otter's, Lontra canadensis, Capture of a Double-crested Cormorant, Phalacrocorax auritus, in British Columbia's Gulf Island Waters

2007 ◽  
Vol 121 (3) ◽  
pp. 325
Author(s):  
Michael H. H. Price ◽  
Clare E. Aries
Keyword(s):  
Lontra Canadensis ◽  
Phalacrocorax Auritus ◽  
River Otter ◽  
Freshwater Lakes ◽  
Marine Bird ◽  
River Otters

Direct and apparent predation events by River Otters (Lontra canadensis) on birds have been recorded on marine islands and freshwater lakes. We add to this the first known observation of a River Otter capturing a marine bird on the ocean.

scholarly journals Fatty acid analysis as a tool to infer the diet in Illinois river otters (Lontra canadensis)

2014 ◽  
Vol 56 (1) ◽  
pp. 16 ◽  
Author(s):  
Damian Satterthwaite-Phillips ◽  
Jan Novakofski ◽  
Nohra Mateus-Pinilla
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Analysis ◽  
Lontra Canadensis ◽  
Illinois River ◽  
River Otters

scholarly journals River Otter, Lontra canadensis, Food Habits in the Missouri Ozarks

2008 ◽  
Vol 122 (4) ◽  
pp. 303 ◽  
Author(s):  
Nathan M. Roberts ◽  
Charles F. Rabeni ◽  
John S. Stanovick ◽  
David A. Hamilton
Keyword(s):  
Smallmouth Bass ◽  
Lontra Canadensis ◽  
Micropterus Dolomieu ◽  
Widespread Occurrence ◽  
River Otters ◽  
Lepomis Megalotis ◽  
Rock Bass ◽  
Longear Sunfish ◽  
The Mean ◽  
Ambloplites Rupestris

The reintroduction of River Otters (Lontra canadensis) between 1982 and 1992 resulted in widespread occurrence of the species throughout the Missouri Ozarks. This study examined otter diets from the vicinity of two Ozark streams in relation to seasonal and spatial trends. Otter scats (N = 4750) were collected and analyzed from the Osage Fork River and Big Piney River during the summer and winter seasons of 2001 and 2002. During the winter (January-March), fish occurred in 86% of the samples. During the summer (June–August), occurrence of fish dropped to approximately 15% for both rivers. Seven families of fish were identified in the diets, with Centrarchidae being most common regardless of river or season. Within the Centrarchidae, the genus Lepomis (mostly Longear Sunfish, Lepomis megalotis) was most common, with Micropterus (mostly Smallmouth Bass, Micropterus dolomieu) and Rock Bass (Ambloplites rupestris) also well represented. The mean age of Ambloplites consumed (mean = 3.3 years) was consistently older than that of either Micropterus (mean = 2.54 years) or Lepomis (mean = 2.78 years). Crayfish were recovered from a mean of 85.2% of scats in the winter and 99% in the summer. Smaller fish and crayfish were more common from the upper reaches of the streams while larger fish were prevalent in the lower reaches.

Sign in / Sign up

Export Citation Format

Share Document