Feral Mus Musculus Research Articles

Serological evidence that Mus musculus is the natural host of Theiler's murine encephalomyelitis virus

Theiler's murine encephalomyelitis virus (TMEV) infection is maintained in mouse colonies by fecal-oral spread (with no apparent role for persistent central nervous system infection) from an acutely infected animal to another. Therefore, serological methods offer the principal way to assess infection in mice and related rodent populations. Infection of mouse colonies with TMEV appears to be worldwide, yet no systematic serologic studies have been reported. In this study, enzyme-linked immunoassay and neutralization analysis of sera from feral Mus musculus obtained from four locations in the United States and one in Russia revealed antibodies to purified TMEV and two linear viral peptide epitopes in more than 50% of the sera derived from the five different locations. A similar analysis of sera from 26 species of related rodents trapped at multiple locations in North America and Europe indicated the presence of anti-TMEV antibodies only in a small proportion of water and bank voles that belong to a different subfamily. These results indicate that Mus musculus is the natural host of TMEV.

Molecular analysis of APRT deficiency in mouse P19 teratocarcinoma stem cell line

We have used four gene probes specific for mouse chromosome 8, including adenine phosphoribosyltransferase (aprt), to demonstrate that the P19 teratocarcinoma stem cell line contains two distinct chromosome 8 homologs. One represents the common laboratory mouse C3H (Mus musculus domesticus) homolog while the second homolog was presumably contributed by a feral Mus musculus musculus animal. Six cell lines with APRT heterozygous deficiencies were isolated from P19 subclones. A molecular analysis of these heterozygotes demonstrated that three arose by deletion of the Mus musculus musculus aprt allele and three arose by aprt gene inactivation. APRT homozygous deficient cell lines were isolated from both classes of heterozygote; most contained little or no detectable APRT activity. When the heterozygous deficiency was due to deletion of the Mus musculus musculus aprt allele, the most frequent event yielding homozygous deficient cell lines was associated with loss of heterozygosity for all tested markers on the Mus musculus domesticus homolog indicating chromosome loss. In contrast, when the initial event resulting in APRT heterozygous deficiency was gene inactivation, homozygotes arose predominantly from gene deletion or a second inactivation event. These results suggest a potential relationship between the first- and second-step events resulting in APRT deficiencies.

Habitat Preference and Reproduction of Feral House Mice, Mus musculus, during Plague and Non-Plague Situations in Western Australia

In Western Australia feral Mus musculus are well established in the southern half of the State, including remote, arid desert situations. In the South West Division Mus have a distinct spring-summer breeding period, with some breeding in autumn after favourable climatic conditions. A plague in autumn 1975 is described and abundance, fecundity, trapping behaviour and habitat selection are compared between plague and non-plague situations. It is considered that abundant rainfall during the two preceding years caused the plague. Decline of the plague coincided with the onset of winter; there is some evidence to suggest that shelter more than food limited numbers, but the decline was probably also influenced by intrinsic factors. In wheatbelt areas of Western Australia Mus are most abundant in samphire heaths.

Isoenzyme pattern of HPRT in murine erythrocytes: control by an autosomal locus.

A locus on chromosome 7 controls the electrophoretic mobility of hypoxanthine phosphoribosyltransferase (HPRT) isoenzymes in mouse erythrocytes, but not in several other tissues. This locus is designated Hma (HPRT mobility alteration) and maps very close to the Hbb locus. The A/J, AKR/J, AU/SsJ, BALB/cJ, CBA/J, C3H/HeJ, DBA/2J, LP/J, RF/J, SEA/Gn, ST/BJ, and 129/J strains and our population of Swiss albino mice have the Hmaa allele. Hmaa is dominant to Hmab, which is found in the C57BL/6J, C57BL/KsJ, C58/J, LT/Sv, MA/MyJ, SJL/J, and SWR/J strains. Both alleles are found in feral Mus musculus. In our conditions, homozygotes for Hmab have two major bands of HPRT activity after electrophoresis of extracts of erythrocytes and of other tissues. Heterozygotes and Hmaa homozygotes have three bands in erythrocyte extracts but two band in other tissues.

The effects of an insecticide stress on genetic composition and population dynamics of a population of feral Mus musculus

1. A feral population of Mus musculus was placed in 8 quarter-acre enclosures, equally divided into test and control grids; treated mice were exposed to a total of 8.8 kg of the carbamate insecticide Sevin. 2. Chi-square values indicated no significant allele frequency changes in serum esterase loci ES-2 and ES-5 between pre-and post-spray populations. 3. The mean number of captures per trapping date showed that test populations were significantly larger but fluctuated more than those in control grids; percent survival was slightly better in test grids. 4. Significant differences in population growth or genetic variation of Mus musculus cannot be attributed to the application of Sevin.

Auditory sensitivity in mice: Peromyscus and Mus musculus

Summary Auditory evoked potentials from the posterior colliculus were used to measure auditory threshold in Peromyscus leucopus, P. boylii , feral Mus musculus and strain BALB/cJ and DBA/2J laboratory mice. Moderate Nembutal anaesthesia had no consistent effect on the shape, amplitude, latency or threshold of the evoked potentials. Peromyscus boylii and young P. leucopus appear to have a high frequency sensitivity similar to that of the bat Myotis lucifugus up to about 70 kHz. The feral Mus musculus were more sensitive to higher frequencies than any of the laboratory mice tested, having lowest thresholds at about 20 kHz. The high frequency sensitivity of strain DBA/2J mice declines rapidly with age, which probably explains their loss of audiogenic seizure susceptibility with age. Mice of strain BALB/cJ were most sensitive to frequencies of about 12 kHz. Their high freuency sensitivity tends to decline with age, but not as rapidly or consistently as in strain DBA/2J mice. The high incidence of sensory deficits in laboratory mice, and the difficulty of detecting them, can confound the results of behavioural studies on inbred laboratory mouse strains.

Interactions of Peromyscus and Mus in a One‐Acre Field Enclosure

Peromyscus polionotus (old—field mice) and feral Mus musculus (house mice) have coexisted in a large old—field area at the AEC Savannah River Plant for 12 yr following removal of human habitations and the abandonment of agriculture in the region, but in two replicate experiments a Mus population has failed to survive when the two species were confined to a one—acre enclosure in the field. In the second experiment, as described in this paper, five Mus were introduced into the enclosure in December 1960 and nine Peromyscus in June 1961. Rapid population growth in both species occurred in the fall of 1961 until about 23 of each species were present, a much bigger density than occurred outside the enclosure. A decline in recruitment rate and a continued high disappearance rate in the Mus population resulted in a gradual decline and extinction of this species; whereas the Peromyscus population maintained itself at a level of 20 to 28 individuals. The two species at first occupied separate areas in the enclosure, but common occupancy of feeding areas increased as the density increased. It was concluded that interspecific competition for seeds was important in the outcome of the experiment, and that the migratory behavior of Mus greatly reduces competition with the more sedentary Peromyscus when populations of the two species are not confined to a limited area.