Seasonal variation in body weight, fat, and behavior of California ground squirrels (Spermophilus beecheyi)

1989 ◽  
Vol 67 (6) ◽  
pp. 1425-1433 ◽  
Author(s):  
Kay E. Holekamp ◽  
Scott Nunes
Keyword(s):  
Body Weight ◽  
Social Behavior ◽  
Body Mass ◽  
Ground Squirrels ◽  
Spermophilus Beecheyi ◽  
Fat Pad ◽  
Annual Cycles ◽  
Focal Animal ◽  
And Behavior ◽  
California Ground Squirrels

Annual cycles of activity and reproduction were documented in a population of California ground squirrels (Spermophilus beecheyi) in coastal California. Behavior, body mass, and reproduction were monitored in marked individuals between November 1983 and January 1986 through regular focal animal observation and livetrapping. Mass measures for reproductive tracts and gonadal fat pads were concurrently collected from a separate population of animals sacrificed in the laboratory. Mass and feeding behavior varied with sex and age. Surface activity, body weight, fat pad mass, and food consumption appeared to be closely related in this population. Fat pad mass was greater in nonreproductive than in reproductively active members of both sexes, as was body mass among males. Female body mass was greatest during pregnancy. Comparisons among reproductive status groups within each sex revealed significant differences in feeding, resting, vigilance, locomotor activity, and social behavior. Comparison with other populations suggested that S. beecheyi is highly variable with respect to demography, seasonal activity, timing of reproduction, and social behavior.

scholarly journals Performance and ingestive and social behavior of young cattle with different sexual conditions supplemented in Aruana pasture

2018 ◽  
Vol 39 (6) ◽  
pp. 2565
Author(s):  
Odilene De Souza Teixeira ◽  
Ivan Luiz Brondani ◽  
Dari Celestino Alves Filho ◽  
José Laerte Nörnberg ◽  
Jonatas Cattelam ◽  
...  
Keyword(s):  
Body Weight ◽  
Social Behavior ◽  
Agonistic Behavior ◽  
Lower Cost ◽  
Composition Analysis ◽  
Young Cattle ◽  
Energy Supplementation ◽  
And Behavior ◽  
Average Body ◽  
Average Body Weight

This study was conducted aiming at measuring the performance and behavior of beef cattle surgically castrated, immunocastrated or non-castrated, finished at 18 months old in Aruana pasture and with energy supplementation. Thirty-nine male bovines with an initial average body weight and age of 284.1 ± 31.4 kg and 14 months old, respectively, were used. The bromatological composition analysis and productive parameters of the pasture did not differ between treatments. The performance of young cattle was not changed by the sexual condition. When evaluating the agonistic behavior, the non-castrated bovine presented a higher number of activities, such as threats and fights, in relation to those immunocastrated. The time spent on the feeder by non-castrated young cattle (56.20 minutes) was higher than that observed for surgically castrated or immunocastrated (41.43 and 32.38 minutes, respectively). The combination between the correct management of Aruana pasture and use of supplementation showed to be promising for finishing bovines. Both surgically castrated and immunocastrated steers demonstrated to be equivalents in the performed evaluations. Therefore, if the farmer chooses castration, the use of immunocastration is suggested. This practice is less invasive, preserves animal welfare more than surgical castration, and has a lower cost.

Physical and behavioral postnatal development of woodchucks (Marmota monax)

1991 ◽  
Vol 69 (4) ◽  
pp. 1040-1047 ◽  
Author(s):  
J. Ferron ◽  
J.-P. Ouellet
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Social Behavior ◽  
Postnatal Development ◽  
Tail Length ◽  
Postnatal Growth ◽  
Behavioral Development ◽  
Ground Squirrels ◽  
Behavioral Repertoire ◽  
Marmota Monax

The physical and behavioral postnatal development of woodchucks (Marmota monax) was analyzed from birth to 42 days of age, the age at which weaning begins. Postnatal growth was evaluated by means of daily measurements of body weight, body length, tail length, and length of hind foot. Data on length of ear pinnae, vibrissae, and fur, and on the timing of appearance of some events of physical development are also presented. We considered postnatal development of locomotion, alertness, exploratory behavior, feeding, and comfort and social behavior. Our results indicate no sexual dimorphism in body size in young woodchucks, despite its occurrence in adults. Intraspecific comparisons reveal that woodchucks from different populations show marked variation in growth rate. The high level of intraspecific variation in developmental rates of sciurid rodents provides a warning to those performing interspecific comparisons. The data also suggest that the ratio of growth rate to adult body weight is not related to environmental severity. Behavioral development in M. monax is similar to that of ground squirrels but faster than that of tree squirrels and flying squirrels. There is also no direct relationship between size and timing of behavioral development in sciurid rodents. The behavioral repertoire of young woodchucks is simpler than that of young Spermophilus lateralis, another asocial species. It is possible that specific differences in rates of development of social interactions led to such differentiation in the repertoire of social behavior.

Disease Surveillance of California Ground Squirrels (Spermophilus beecheyi) in a Drive-through Zoo in Oregon, USA

2017 ◽  
Vol 53 (3) ◽  
pp. 667-670
Author(s):  
Julia Ter Beest ◽  
Andrew Cushing ◽  
Modesto McClean ◽  
Wendy Hsu ◽  
Robert Bildfell
Keyword(s):  
Disease Surveillance ◽  
Ground Squirrels ◽  
Spermophilus Beecheyi ◽  
California Ground Squirrels

scholarly journals Quantitative Shedding of Two Genotypes of Cryptosporidium parvum in California Ground Squirrels (Spermophilus beecheyi)

2001 ◽  
Vol 67 (6) ◽  
pp. 2840-2843 ◽  
Author(s):  
Edward R. Atwill ◽  
Sergio Maldonado Camargo ◽  
Ralph Phillips ◽  
Laura Herrera Alonso ◽  
Kenneth W. Tate ◽  
...  
Keyword(s):  
Cryptosporidium Parvum ◽  
Ground Squirrels ◽  
Spermophilus Beecheyi ◽  
California Ground Squirrels

ABSTRACT Sixteen percent of California ground squirrels (Spermophilus beecheyi) were found to be shedding an average of 53,875Cryptosporidium parvum oocysts/g of feces. Male squirrels had a higher prevalence and higher intensity of shedding than did female squirrels. The majority of C. parvum isolates matched a bovine-murine genotype, with a few isolates resembling a porcine genotype. Higher intensities of shedding by males may enhance dissemination and genotypic mixing of this protozoa given males' proclivity to disperse to nonnatal colonies.

Development of Antisnake Defenses in California Ground Squirrels (Spermophilus Beecheyi): II. Microevolutionary Effects of Relaxed Selection From Rattlesnakes

Behaviour ◽  
1993 ◽  
Vol 124 (1-2) ◽  
pp. 137-162 ◽  
Author(s):  
Richard G. Coss ◽  
Naomie S. Poran ◽  
Kevin L. Gusé ◽  
David G. Smith
Keyword(s):  
Population Level ◽  
Ground Squirrels ◽  
Species Discrimination ◽  
Spermophilus Beecheyi ◽  
Relaxed Selection ◽  
Virtual Absence ◽  
Rare Site ◽  
California Ground Squirrels ◽  
Two Populations

AbstractNonvenomous Pacific gopher snakes (Pituophis melanoleucus catenifer) and venomous northern Pacific rattlesnakes (Crotalus viridis oreganus) have coexisted in a predator-prey relationship with California ground squirrels (Spermophilus beecheyi) for many thousands of generations. This long-term relationship has fostered in ground squirrels the evolution of antisnake defenses that consist of physiological resistance to rattlesnake venom and behavioral tactics of probing and harassing that might facilitate snake-species discrimination. Snake harassment by adults might also protect pups by interfering with snake hunting activities. Some ground squirrel populations have colonized habitats where rattlesnakes, but not gopher snakes, are rare or absent. Initial research indicates that squirrels experiencing relaxed selection from rattlesnakes are very aggressive toward their remaining nonvenomous snake predator, the gopher snake. Two experiments investigated the effects of relaxed selection from rattlesnakes by examining: 1) changes in level of venom resistance, 2) the reorganization of antisnake behaviors in lab-born pups and wild-caught adults from different sites, and 3) the role of natural experiences on the development of antisnake behavior in a rattlesnake-adapted population. Level of venom resistance was examined by an in vitro radioimmunoassay of serum-to-venom binding of two populations of Douglas ground squirrels (S. b. douglasii). The ancestors of one population are estimated to have experienced relaxed selection from rattlesnakes for about 9,000 years based on genetic distance and radiocarbon analyses. The antisnake behavior of 60-73 day-old lab-born pups from these two populations was video taped during presentations of a caged rattlesnake or gophcr snake for alternate 5-min trials in a seminatural laboratory setting. Two groups of wild-caught adult Beechey groundsquirrels (S. b. beecheyi) were studied using the same protocol for examining antisnake behavior. One group was obtained from a population that recently colonized a rattlesnake-rare site and exhibits moderate venom resistance. The second group came from a population that exhibits very low venom resistance and inhabits a rattlesnake-free site; relaxed selection from rattlesnakes for this population is estimated to span approximately 60,000 years. Comparisons of Douglas ground squirrels from rattlesnake-abundant and rettlesnakerare sites revealed that venom resistance declined approximately 59% after an estimated 9,000 years of relaxed selection from rattlesnakes. Lab-born Douglas pups from the same rattlesnake-rare site were more aggressive toward the gopher snake than toward the rattlesnake whereas pups from the population experiencing predation from both species of snake treated both snakes as similarly dangerous. Unlike pups, wild-caught adults from the rattesnake-adapted population harassed the rattlesnake more intensely than the gopher snake, a phenomenon that may reflect their experience with snakes in nature and larger body size that reduces their vulnerability to envenomation. Wild-caught Beechey ground squirrels that recently colonized a rattlesnake-rare site did not differentiate the rattlesnake and gopher snake whereas Beechey ground squirrels whose ancestors have experienced prolonged relaxed selection from rattlesnakes were more aggressive toward the gopher snake. Consistent with previous findings, prolonged relaxed selection from rattlesnakes, but not gopher snakes, appears to have reduced the inhibition to harass large gopher snakes. This microevolutionary shift in increased aggressiveness toward the gopher snake could result from the virtual absence of any risk in misidentifying rattlesnakes from gopher snakes.

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