|
Escherichia coli,Bacillus mycoides,Klebsiella sp.,and Bacteriodes sp.have been
<br /> reported from the cecum. The general occurrence of trematodes, cestodes and
<br /> nematodes in a population tends to be very low. The trematodes Norocotylus
<br /> hassafi, Plagiorchis proAmus, Plagiorchis sp., Quinqueserialis quinqueserialis,
<br /> Quinqueserialis sp., Schisrosomatiuim douthitti, and Echinostoma sp. have been
<br /> reported. Cestodes reported include Mesocestoides sp., larval Taenfa musrelae,
<br /> Choanoraenia sp., and Hymenolepis sp. Reported nematodes are Subulura
<br /> ungulatus, Spirocerca zapi, Mastophorus muris, Citellinoides zapodis,Rictularia
<br /> sp., and Longistriata dalrymplei. The ticks Dermacentor variabilis and lxodes
<br /> muris have been found on Z. hudsonius, with the latter found on 36 of 864 mice
<br /> examined in New York. The chigger mites Trombicula micron, T. subsignara,
<br /> Euschongastia diversa acura, Androlaelaps fahrenholzi and Haemogamasus
<br /> hirsutus have been reported. The most abundant external parasite of Z. hudsonius
<br /> in New York and Indiana is the hypopus (transport form) of Dermacarus
<br /> hypudaei, which does not feed on the mouse, and is not found in adult form on
<br /> the mouse. No other mites have been reported with any regularity, but the
<br /> chiggers Neotrombicula subsignata, Eutrombicula alfreddugesi, and
<br /> Neoschongasaa sp., and mites Eularlaps stabularis, Laelaps kochi,
<br /> Haemogomaasus alaskensis, and a few free-living mites considered accidentals
<br /> have been reported. Flea occurrence is also low in a population, and species
<br /> reports include Orchopeas leucopus, Megabothris asio, M. wagneri, M. quirini,
<br /> Stenopomia americana,Corrodopsylla curvata,and Ctenoprhalmus pseudagyrates.
<br /> Larval bottlies, Curerebra, often have been found on Z. hudsonius. Only one
<br /> louse, probably Neohaematopinus sp., was found on 864 Z. hudsonius examined
<br /> in Ne'w York.
<br /> 9. Reproduction
<br /> A. Breeding Season- The breeding season begins shortly after Z. hudsonius emerge
<br /> from hibernation in the spring, and reproduction continues until a few weeks
<br /> before the species hibernates in autumn (Krutzsch 1954). Quimby (1951) stated
<br /> that date of emergence from hibernation varies from year to year, and hence the
<br /> beginning of the breeding season also varies. Quimby (1951)presented data from
<br /> a Minnesota population where the dates of birth of Z. hudsonius ranged from June
<br /> 15 to August 23. Information from North Carolina and Georgia indicate a longer
<br /> breeding season into late September (Krutzsch 1954). The breeding season,
<br /> therefore, probably varies geographically. The breeding season varies seasonally
<br /> in that a Michigan population showed two peaks of breeding activity in spring
<br /> and another in late summer, with little activity during the intervening summer.
<br /> Quimby (1951) ascertained that three peaks occur in Minnesota, occurring in late
<br /> June, mid- and late July, and mid-August. Many Z. hudsonius in New York have
<br /> two litters per year since 67% of the adult females taken in the first major
<br /> breeding period (May 21 to June 20) were pregnant, or had given birth recently,
<br /> and 84% of the adult females taken from July 21 to August 20 were pregnant or
<br /> had recently given birth (Whitaker 1972).
<br /> B. Gestation Period- The gestation period of nonlactating, caged Z. hudsonius was
<br /> approximately 18 days, with gestation being prolonged in lactating females
<br /> (Quimby 1951).
<br /> C. Nesting- Preble (1899) stated that during the latter part of the summer Zapus
<br /> makes a globular nest of grass about 4 inches in diameter, with a small entrance
<br /> Fu St..Survey
<br /> Muds:b.1993
<br /> ld
<br />
|