Seasonal variation of red blood cell survival in desert bighorn sheep (Ovis canadensis cremnobates)

1984 ◽  
Vol 62 (7) ◽  
pp. 1227-1231 ◽  
Author(s):  
Jack C. Turner
Keyword(s):  
Body Weight ◽  
Seasonal Variation ◽  
Life Span ◽  
Blood Cells ◽  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Desert Bighorn Sheep ◽  
The Mean ◽  
Ad Libitum ◽  
Free Ranging

The life-span of red blood cells (RBCs) in captive and free-ranging desert bighorn sheep was measured with [32P]diisopropylfluorophosphate. The mean winter RBC life-span (156.6 days) was not significantly affected by season for captive animals maintained on a high nutritional plane and water, ad libitum. Free-ranging bighorn demonstrated a significant (P < 0.001) difference between mean winter (155.9 days) and summer (203.9 days) RBC survival. Dehydration of captive bighorn significantly increased RBC survival, closely approximating that found in summer free-ranging animals. Desert bighorn RBCs exhibited an aseasonal facultative response to the availability of water. RBC life-span was significantly (P < 0.05) increased from 153.5 to 197.7 days in animals experiencing extreme dehydration. The large spleen, relative to body weight, may accommodate extensive fluctuations in total RBC volume measured during dehydration and rehydration, preventing premature RBC degradation and an increased water requirement.

Diurnal periodicity of plasma Cortisol and corticosterone in desert bighorn sheep demonstrated by radioimmunoassay

1984 ◽  
Vol 62 (12) ◽  
pp. 2659-2665 ◽  
Author(s):  
Jack C. Turner
Keyword(s):  
Plasma Cortisol ◽  
Bighorn Sheep ◽  
Cortisol Concentration ◽  
Class Iii ◽  
Desert Bighorn Sheep ◽  
Group Interactions ◽  
Specific Radioimmunoassay ◽  
Significant Difference ◽  
The Mean ◽  
Free Ranging

A sensitive and specific radioimmunoassay (RIA) for Cortisol and corticosterone was validated for desert bighorn sheep (Oviscanadensis cremnobates) plasma. Statistical and physiological validation of assay accuracy, precision, sensitivity, and specificity demonstrated the RIA to be reliable. Coefficients for intra- and inter-assay variation were 1.20 and 2.35% for Cortisol and 3.50 and 3.97% for corticosterone, respectively. Sensitivity was 3.3 and 4.9 pg for cortisol and corticosterone, respectively. A distinct diurnal rhythm in plasma cortisol and corticosterone synchronous with photoperiod was found in free-ranging and captive bighorn sheep. A significant difference (P < 0.01) existed between the mean 24-h plasma cortisol concentration for captive (33.04 ± 5.97 ng/mL) and free-ranging (49.20 ± 8.17 ng/mL) bighorn. Corticosterone levels were not significantly distinct between captive and free-ranging bighorn. The mean scotophase cortisol concentration in free-ranging class III rams (60.97 ± 3.21 ng/mL) was significantly greater (P < 0.05) than the mean scotophase cortisol concentration (54.03 ± 5.97 ng/mL) of the free ranging group. Absence of group interactions in solitary rams may be sufficiently stressful so as to entrain increased plasma cortisol concentrations.

Red cell life span in the turtle and toad

1962 ◽  
Vol 203 (6) ◽  
pp. 1188-1190 ◽  
Author(s):  
Paul D. Altland ◽  
Kirkland C. Brace
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Blood Cells ◽  
The Body ◽  
South American ◽  
Red Cell ◽  
Cell Life ◽  
Box Turtles ◽  
Rate Characteristic ◽  
The Mean

Estimates of the mean life span of the red blood cells of box turtles and South American giant toads were made with glycine-2-C14. The mean life span of the turtle red cells probably lies between 600 and 800 days and that of the toad between 700 and 1,400 days. The body weight, hematocrit, and hemoglobin values remained at relatively normal levels for 7 years in turtles and nearly 2 years in toads. These results indicate that the low metabolic rate, characteristic of poikilotherms, is correlated with a long red cell life span.

scholarly journals Desert Bighorn Sheep: Changes in Genetic Variation Over Time and the Impact of Merging Populations

2014 ◽  
Vol 5 (1) ◽  
pp. 3-13 ◽  
Author(s):  
Philip W. Hedrick ◽  
John D. Wehausen
Keyword(s):  
Genetic Variation ◽  
New Mexico ◽  
Monitoring And Evaluation ◽  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Mexican Population ◽  
Desert Bighorn Sheep ◽  
Two Generations ◽  
The Impact ◽  
Over Time

Abstract Founder effects, genetic bottlenecks, and genetic drift in general can lead to low levels of genetic diversity, which can influence the persistence of populations. We examine genetic variation in two populations of desert bighorn sheep Ovis canadensis from New Mexico and Mexico to measure change over time and evaluate the impact of introducing individuals from one population into the other. Over about three generations, the amount of genetic variation in the New Mexico population increased. In contrast, over about two generations the amount of genetic variation in the Mexican population decreased by a great extent compared with an estimate from another Mexican population from which it is primarily descended. The potential reasons for these changes are discussed. In addition, although both populations have low genetic variation, introduction of Mexican rams into the New Mexico population might increase the amount of genetic variation in the New Mexico population. Overall, it appears that management to increase genetic variation might require substantial detailed monitoring and evaluation of ancestry from the different sources and fitness components.

Factors influencing heart rate in free-ranging bighorn sheep: a physiological approach to the study of wildlife harassment

1979 ◽  
Vol 57 (10) ◽  
pp. 2010-2021 ◽  
Author(s):  
Robert A. MacArthur ◽  
Ronald H. Johnston ◽  
Valerius Geist
Keyword(s):  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Activity Level ◽  
Base Line ◽  
Vehicular Traffic ◽  
Behavioral Reactions ◽  
Factors Influencing ◽  
Close Range ◽  
Physiological Approach ◽  
Free Ranging

The telemetered heart rates (HR) of unrestrained female bighorn sheep (Ovis canadensis canadensis) were recorded under various behavioral and environmental circumstances. In all ewes HR varied positively with activity level and inversely with distance to a road traversing the study area. The HR recorded from animals moving at night or through timber by day were higher than during daytime movement across open slopes.Responses to transient stimuli varied greatly. The appearance of free-ranging canids evoked maximal increases in HR in all ewes. Vehicular traffic and aircraft elicited HR responses only at close range (< 200 m). Most (78.1%) HR responses to disturbing stimuli preceded or occurred in the absence of overt behavioral reactions. The HR usually peaked within 60 s of the onset of the response and recovered to predisturbance base line in less than 200 s. The appearance and continued presence (1–10 min) of a human within 50 m of the sheep resulted in a 20% rise in mean HR. The significance of these findings is discussed in relation to the behavior, ecology, and bioenergetics of bighorn sheep.

Breeding Biology of Brushtail Possums Trichosurus vulpecula (Marsupialia, Phalangeridae) in Captivity.

1995 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
R.T. Gemmell
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Post Partum ◽  
Young Female ◽  
Brushtail Possum ◽  
Lactation Period ◽  
In Captivity ◽  
In The Wild ◽  
The Mean ◽  
Reproductive Capability

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.

Population subdivision among desert bighorn sheep ( Ovis canadensis ) ewes revealed by mitochondrial DNA analysis

1999 ◽  
Vol 8 (1) ◽  
pp. 99-106 ◽  
Author(s):  
W. M. Boyce ◽  
R. R. Ramey ◽  
T. C. Rodwell ◽  
E. S. Rubin ◽  
R. S. Singer
Keyword(s):  
Mitochondrial Dna ◽  
Dna Analysis ◽  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Population Subdivision ◽  
Desert Bighorn Sheep ◽  
Mitochondrial Dna Analysis

Desert bighorn sheep (Ovis canadensis) recognition from camera traps based on learned features

2021 ◽  
pp. 101328
Author(s):  
Manuel Vargas-Felipe ◽  
Luis Pellegrin ◽  
Aldo A. Guevara-Carrizales ◽  
A. Pastor López-Monroy ◽  
Hugo Jair Escalante ◽  
...  
Keyword(s):  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Camera Traps ◽  
Desert Bighorn Sheep ◽  
Learned Features
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