In 1926, Crozier and Pincus first reported that 2-week-old rats placed head-down on an inclined plane orient in a head-up direction; this response is called negative geotaxis. In Experiment 1, we replicated this finding by testing 12- to 14-day-old rats on an inclined plane covered with wire mesh. Pups oriented in a head-up direction and avoided the head-down direction at inclines of 45 degrees...

Weanling Sprague Dawley rat pups (Rattus norvegicus) selected between 2 safe palatable diets in concordance with the preferences of either an adult or a juvenile conspecific model (Experiment 1). Nevertheless, weanlings chose to feed more in the vicinity of an adult than in the vicinity of a juvenile, thus fulfilling the prediction of an adaptive feeding strategy (Experiment 2). The weanlings' ...

Country Reservoirs Vectors Bolivia Akodon sp Xenopsylla cheopis Rattus rattus Pulex irritans Brazil Akodon sp X. cheopis Oryzomys sp Callomys sp Bolomy sp Monodelphis deomestica Ecuador R rattus P. irritans R. norvegicus R. alexandrinus Akodon mollis Oryzomys sp Phyllotis sp Scirurus stramineus United States Marmot (Cynomys sp) Orchopeas sexdentatus Rabbits Oropsylla montana Rats (Dipodomys sp)...

During February 2004 and September 2005, Xenopsylla cheopis were collected from small mammal hosts during rodent-bone disease surveys in Jakarta and Bandung, Indonesia. During 4 trap nights in Jakarta, 4 rodent species (Rattus exulans, Rattus norvegicus, Rattus tanezumi and Mus musculus) and one shrew species (Suncus murinus) were collected. Rattus tanezumi had the highest X. cheopis load (128 ...

The authors used laboratory rats (Rattus norvegicus) of known relatedness and contrasting familiarity to assess the potential effect of preexperimental social experience on subsequent social recognition. The authors used the habituation-discrimination technique, which assumes that multiple exposures to a social stimulus (e.g., soiled bedding) ensure a subject discriminates between the habituati...

We have identified and determined the sequence and organization of a new rat satellite DNA in Rattus rattus, the roof rat. This satellite DNA, which we call R. rattus satellite I', consists of tandem arrays of a 185 base pair (bp) repeat unit that we call a'. a' is 86% homologous to a 185 bp portion of the 370 bp repeat unit of the previously described rat satellite [Pech et al. (1979) Nucleic ...

The potential for hantaviral transmission among wild Norway rats by wounding associated with aggressive interactions was evaluated using a prospective sero-epidemiological study coupled with a mark-release-recapture survey. There was a significant association between an animal's serological status and the presence of wounds. Longitudinal studies of marked and released animals showed seroconvers...

Acute and chronic cases of toxoplasmosis in Rattus norvegicus and Rattus rattus mindanensis caught in agricultural, commercial and residential sites in Dasmariñas, Cavite, Philippines were determined serologically. Fifty-eight percent of R. norvegicus and 42.0% of R. r. mindanensis were positive for anti-T. gondii antibodies (Abs). Infection was higher in male rats, and those caught in the comm...

A survey of ectoparasites on rodents was carried out bimonthly from April 2008 to March 2009 in 3 districts of Sukhothai Province, northern Thailand. A total of 130 rodents comprising 8 species of hosts were captured and examined for ectoparasites. The hosts examined were Bandicota indica, Bandicota savilei, Rattus losea, Rattus rattus, Rattus exulans, Rattus norvegicus, Menetes berdmorei and T...

Amastigotes of a Kenyan strain of Leishmania donovani from a previously infected hamster were used to inoculate Rattus rattus and the laboratory white rat intracardially. The animals were sampled at 2, 4, 6, and 12 weeks post-inoculation to determine infectivity and total parasite burdens in the liver and spleen. Higher parasite burdens were observed in the livers and spleens of R. rattus. Para...