Neotoma Cinerea Research Articles

Ixodes spinipalpis Hadwen and Nuttall (Ixodidae) from southern Alberta

Five nymphs and one larva of Ixodes spinipalpis Hadwen and Nuttall were collected from a grey bushy-tailed wood rat, Neotoma cinerea cinerea (Ord.) in a prairie habitat in southern Alberta.

Susceptibility of Various Species of Rodents to the Relapsing Fever Spirochete, Borrelia hermsii

In a study to determine susceptibility to Borrelia hermsii of various rodents commonly found in or near places where human cases of relapsing fever occurred, chipmunks (Eutamias amoenus), pine squirrels (Tamiasciurus hudsonicus richardsoni), flying squirrels (Glaucomys sabrinus), Columbian ground squirrels (Spermophilus columbianus columbianus), golden-mantled ground squirrels (S. lateralis tescorum), wood rats (Neotoma cinerea cinerea), white-footed deer mice (Peromyscus maniculatus), and meadow voles (Microtus pennsylvanicus) were exposed to spirochetes either by bites of infected Ornithodoros hermsi or by injection of infectious tick suspensions. Daily microscopic examination of blood samples revealed that pine squirrels, chipmunks, and meadow voles responded with spirochetemias of various degrees and length. Pine squirrels were most susceptible and experienced long-lasting and severe spirochetemias accompanied by typical signs of illness. Flying squirrels, Columbian ground squirrels, golden-mantled ground squirrels, wood rats, and white-footed deer mice did not develop demonstrable spirochetal infection.

Contributions to the ecology of Colorado tick fever virus.

Studies were conducted in 3 different habitats in Mill Canyon, Ravalli County, in southwestern Montana on certain biological phenomena that affect the dispersal and maintenance of Colorado tick fever in its natural biocenose. During the study 399 small mammals were captured, in descending order of frequency: Peromyscus maniculatus, Citellus lateralis, Neotoma cinerea, Eutamias amoenus, Clethrionomys gapperi, Microtus longicaudus and Glaucomys sabrinus. Capture-recapture data did not prove amenable to statistical treatment, so comparisons of population levels were made by animals caught per-trap-night. Of the rodents collected, P. maniculatus proved most amenable to manipulation, and populations of this species were stable and uniformly distributed throughout the study area. Adult D. andersoni occurred primarily in alpine meadows; larvae mainly in rock ledges in the same area; nymphs for the most part did not respond to the CO2 technique. Adults and nymphs were active during May to July, while larvae were collected July and August. Infestation of rodents ranged from 16% in C. gapperi to 100% in C. lateralis. C. lateralis and N. cinerea were most often infested: average 7–12 ticks per capture. Ixodes ochotonae was also recorded in the study area. Virus was isolated 32 times from pools of D. andersoni nymphs and larvae off rodents but never from wild-caught unfed larvae. Positive pools ranged from 15% in 1964 to 35% in 1966. The greatest number of positive pools (20–53%) was taken from C. lateralis and N. cinerea. In 1964, 11 of 315 P. maniculatus blood samples, 3.5%, were positive for CTF virus; in 1966, 4 of 68 rodent blood samples, 5.9%, were positive. These latter isolations consisted of 2 samples from P. maniculatus and 2 from C. lateralis. The significance of the data gained in this study in the maintenance of CTF virus within the biocenose is discussed.

Abundance of rodents and fleas as related to plague in Lava Beds National Monument, California.

Plague was found in dead pack rats (Neotoma cinerea) in Lava Beds National Monument. This finding prompted an investigation of the ecology of plague in the area and initiation of subsequent control measures. Eighteen species of mammals were collected and 25 species of fleas were taken. Peromyscus maniculatus and Neotoma cinerea were taken most frequently in the caves. Comparison of species composition and numbers of fleas on these hosts in the caves and on the surface revealed substantial differences in the fleas on these hosts depending upon where they were captured. Fleas from rodent nests taken in caves and on the surface reflected somewhat the same proportion of species on hosts from respective environments. Also most fleas were more numerous on their hosts in caves than on the surface. Some fleas, such as Phalacropsylla allos which are considered rare because few are normally encountered even in museum collections, were found in abundance in the caves. Of notable significance is the variety and abundance of hosts and their fleas in the area and the apparent conducive cave environment for production of fleas. Plague was isolated from specimens of Phalacropsylla allos, Malaraeus sp., Opisodasys keeni, and Orchopeas sexdentatus.

Distribution and Habitat of the Woodrat, Neotoma fuscipes, in Northeastern California

Neotoma fuscipes has been found to occur widely and abundantly over most of the Great Basin sector of northeastern California in juniper woodland, open pine forest, and lava bed habitats. Past records have shown only slight penetration into this region east of the Cascade range. Early collectors found only Neotoma cinerea in localities where N. fuscipes now is abundant. It is suggested that weather extremes or possibly plague epizootics in the past have severely affected the range of N. fuscipes. The dusky-footed woodrat, Neotoma fuscipes, is distributed along the Pacific Coast from the Columbia River to northern Baja California, generally west of the deserts and Great Basin. In northern California it occurs in the coastal belt, and extends across the head of the Sacramento Valley and along the west slope of the Sierra Nevada. It is well known from Shasta and Scott valleys, Siskiyou County. However, the species has been recorded from just two areas east of the Sierra-Cascade divide-near Tennant and at Crescent Butte, Lava Beds National Monument, in easternmost Siskiyou County (Hooper, 1938), and in the Pit River drainage east to Hayden Hill, north- western Lassen County (Goldman, 1910). We have found Neotoma fuscipes to be widespread and abundant east of the Cascade divide over much of the Great Basin sector of northeastern California.

Observations on the ultimobranchial gland in small wild and laboratory mammals, with special reference to the histochemical localization of polysaccharides

AbstractThis is the last of a series of observations involved in a comparative histological study of the ultimobranchial body in vertebrates. Complete serial longitudinal or transverse paraffin sections were made of formol alcohol, Bouin's, and formalin‐fixed ultimobranchial and thyroid tissues that had been removed from adult specimens of the cat, cotton rat, ground squirrel, Guinea pig, kangaroo rat, bushytailed wood rat, rabbit, and raccoon. The alcian blue‐PAS, aldehyde fuchsin‐alcian blue, mucicarmine, alcian blue‐safranin, Best's carmine, and toluidine blue staining procedures show that the glandular mammalian ultimobranchial tissue is capable of producing considerable amounts of various mucosubstances, particularly the acid mucopolysaccharides, and other carbohydrate‐containing materials. The carbohydrate moiety has been histochemically identified as mucopolysaccharides possessing acidic groups, those having both carboxyl and ester sulfate groups; and as glycogen, muco‐and glycoproteins and other carbohydrate‐protein complexes. The differences in the intensity and localization of a given staining reaction reflect not only individual and species variations but also significant differences in the position of the ultimobranchial tissue in relation to the thyroid gland. An accessory thyroid lobule found near parathyroid IV and thymus IV in a bushy‐tailed wood rat may represent a cystic manifestation of the ultimobranchial body because its follicles varied greatly in size and were lined by a thick stratified squamous epithelium. The possible hormonal mechanisms (TSH, thyroxine) involved in the regulation of ultimobranchial activity are discussed in relation to the gland's production, storage, and release of mucopolysaccharides and other secretory substances.

Endoparasitic chiggers: 3. Euschoengastia velata, n. sp. (Acarina), an intradermal parasite of boreal rodents in Montana.

Euschoengastia velata n. sp., found in follicular cysts at the bases of hair tufts of the type host, Neotoma cinerea, is described from western Montana. It is also recorded from a microtine host, presumably Phenacomys intermedius.

Infectious diseases in wild animals in Utah. VII. Experimental infection of rodents with Rickettsia rickettsii.

Summary The quantitative susceptibility of native and standard laboratory rodents to infection with Rickettsia rickettsii was determined using the development of spotted fever group complement-fixing (CF) antibody as the criterion for determining infection. Most species of rodents were moderately to highly susceptible to infection, while two species appeared to be comparatively resistant to infection. The development and persistence of rickettsemia in inoculated rodents was investigated. In most rodents a rickettsemia developed within two days and persisted for up to 16 days after the inoculation of R. rickettsii. The correlation of susceptibility as determined by CF antibody response with susceptibility observed by the development and persistence of rickettsemia was discussed. Of the many species of rodents tested, only one, the bushy-tailed wood rat, appeared to be highly resistant to infection as determined by the methods used. In eight species of rodents tested there was no tendency to develop a latent infection as all rodents had cleared the rickettsiae from their tissues by the fourth week after inoculation of R. rickettsii, as determined by the method employed. The development and persistence of spotted fever group CF antibody was observed in seven species of rodents. Peak titers occurred during the 2nd to 4th week after inoculation and low levels were detectable in most animals several months after inoculation.

Bushy-tailed Wood Rat in the Peace River District, Alberta

Bushy-tailed Wood Rat in the Peace River District, Alberta

The Bushy-Tailed Wood Rat in Southeastern Alaska

The Bushy-Tailed Wood Rat in Southeastern Alaska

The Bushy-Tailed Wood Rat: A Laboratory Colony

Gestation period, litter size, annual breeding cycle, growth rate, post-juvenal molt and rearing methods in captivity are given for the bushy-tailed wood rat, Neotoma cinerea acraia . Observations on territorialism and other related behavior patterns of breeding pairs are recorded.

The Desert Woodrat: A Laboratory Colony

The success of laboratory or simulated epizoological studies and related research involving native mammals may be dependent upon an assured supply of the species being studied. If the research is purely bacteriological in nature, then it is often required that the animals be reared under standard conditions and have a known pedigree—preferably at least second or third generation laboratory-reared stock. After two years of study (1953–55), a breeding colony of desert woodrats, Neotoma lepida lepida Thomas, was established in the Faunal Colony of Ecological Research, University of Utah, at Dugway, Utah. Testing the practicability of this species as a laboratory animal was part of a program designed to examine the mass rearing possibilities in the laboratory of several rodents native to the western Utah desert. Bushy-tailed woodrats, Neotoma cinerea acraia (Elliot), also were reared but on a much smaller scale. This paper reports methods used to produce more than 200 laboratory-bred desert woodrats in close confinement. Other data, such as gestation period, litter size, age of puberty, longevity as breeders, sex ratio and yearly reproductive potential are given. Since a knowledge of the habits of an animal in nature is often helpful in keeping and rearing the species in captivity, certain pertinent field observations on this woodrat are also included. Dependable laboratory and field assistance from B. N. Day and Eddyjo Ekker is gratefully acknowledged. Other Ecological Research personnel who generously contributed advice and assistance include: A. M. Woodbury, Director; D. M. Allred, Chief Ectoparasitologist; E. D. Vest, Chief Ecologist; E. A. Shippee, John Smith and D. D. Parker. Acknowledgment is also extended to Robert Holdenried for reading the manuscript. This work was supported by U.S. Army Chemical Corps contract No. DA-18-064-CML-2639, with the University of Utah. Parent stocks for the colony were obtained from the south end of the …

Fluctuation in the Population of Neotoma cinerea (Woodrat) in Jackson Hole, Wyoming

Fluctuation in the Population of Neotoma cinerea (Woodrat) in Jackson Hole, Wyoming

Occurrence of the Bushy-Tailed Woodrat (Neotoma cinerea) at Fresno, California

Occurrence of the Bushy-Tailed Woodrat (Neotoma cinerea) at Fresno, California

Notes on the Natural History of the Bushy-Tailed Wood Rats of California

Notes on the Natural History of the Bushy-Tailed Wood Rats of California