Carrier State of <I>Pasteurella pneumotropica</I> in Mice and Rats

Abstract

Localizationof Pasteurella pneumotro pica was investigated in the respiratory tract, conjunctiva and vagina of 5-week-old, 10-week-old and retired asymptomatic mice and rats.The highest isolation rate of the organisms was obtained in the pharyngolarynx, showing 85 to 97.5% in carrier mice and 100% in carrier rats. Numbers of the organisms in this site were 103-5 and 107-8 organisms/g tissue in 4-week-old mice and rats, respectively. Isolation rates in the nasal cavity and trachea of the both animals were not so high as those in the pharyngolarynx, but usually higher than those in the external nares.The organisms were rarely isolated from the lung.Isolation of the organisms from the conjunctiva was common in rats, especially in young ones, but rare in mice. About 30% of carrier mice and 50 to 100% of carrier rats harbored the organisms in their vaginas.

Ten Years-long Survey on Pathogen Status of Mouse and Rat Breeding Colonies

“…Pathogen status of laboratory mice and rats in this country has been extensively examined these 10 years by several investigators [3,4,14,16] Swab samples of the external nares and trachea including pharyngo-larynx area were cultured on blood agar, DHL agar (Eiken Co., Tokyo) and PPLO agar for detection of P. pneumotropica [11], B. bronchi septica [9] and M. pulmonis [12], respectively.…”

Colonization Pattern of <I>Pasteurella pneumotroplca</I>in Mice with Latent Pasteurellosis

“…The main colonization sites of P. pneumotropica in the latently infected mice are propably upper respiratory, intestinal and genital tracts [6,11]. However, distribution of the organism in the intestine was not clear, because isolation of the organism from the intestinal samples with conventional media is difficult [11].…”

“…However, distribution of the organism in the intestine was not clear, because isolation of the organism from the intestinal samples with conventional media is difficult [11]. We have therefore developed the selective media, and successfully isolated the organism from the intestinal tract and feces [6].…”

“…The organism is sometimes associated with pneumonia, subcutaneous abscess, conjunctivitis, mastitis, metritis, cystitis and abortion, but often isolated from the latently infected mice [1][2][3][9][10][11][12][13]. Main colonization sites of the organism in mice seem to be respiratory and genital tracts [11,12], and possibly intestinal tract, because the bacterium was isolated also from intestinal and fecal samples in rats [4,7]. However, since no selective medium was available for the isolation of P. pneumotropica from intestinal samples, distribution of the organism in the intestinal tract has not,been fully examined.…”

Antigenic Characterization of <I>Pasteurella pneumotropica</I>Isolated from Mice and Rats

“…It is well known that mice and rats are often healthy carriers of the organism [4,5,7,8,13,17,18], however, host-specific parasitism of the organism has not yet been investigated except our previous study in which rat strains were shown to be inf ective to rats but rarely to mice, while mouse strains were highly inf ective to both animals [12].…”