Serological relationship of some V-factor dependent Pasteurellaceae (Haemophilus sp.) from guineapigs and rabbits

Abstract

Culture of guinea pig and rabbit respiratory tracts for bacteria using X- (haemin) and V- (NAD) factor in agar media detected infection by V-factor dependent Pasteurellaceae (Haemophilus sp.) in three colonies of guinea pigs and a group of rabbits. The 12 Haemophilus strains comprised three API NH codes classed as Haemophilus parainfluenzae and two codes classed as Haemophilus aphrophilus/paraphrophilus. Six cell wall lipid profiles were detected, but these were not related to API NH codes. Both bacteriological properties were used to select strains for serological studies but any relationship between bacteriological and serological properties of the Haemophilus strains was not evident. Varying serological relationships occurred between the newly isolated Haemophilus strains, [Pasteurella] pneumotropica NCTC 8284 and Haemophilus strains previously isolated from rats.

Transmission of rat and guineapig Haemophilus spp. to mice and rats

“…from infected animals of other species such as rats, hamsters and gerbils (Boot et a1. 1994 (Boot et al 1999). [P.]pneumotropica was, however, readily transmitted from guineapigs to the rats which is in line with previous studies in which [P.] pneumotropica was easily transmitted from mice, hamsters and gerbils to rats (Boot et al 1994).…”

“…infected guineapigs (Table 1), as evidence of transmission of the infection was found in the three Gp experiments. The apparent absence of Hae-mophi1us in cultures from exposed rats in experiment Gp3, despite the presence of antibodies, may of course be due, for example, to overgrowth by other bacteria, but the outcome of the experiment agrees with the observation that strains showing API codes Laboratory Animals (2000) 34 7162 lclassed as H. aphrophilusl paraphrophilus by the test system) or 7360 (classed as H. parainfluenzael have until now been cultured only from guineapigs (Boot et al 1999). [P.]pneumotropica was, however, readily transmitted from guineapigs to the rats which is in line with previous studies in which [P.] pneumotropica was easily transmitted from mice, hamsters and gerbils to rats (Boot et al 1994).…”

“…were not epidemiologically related (Table 1). All sources were claimed to be free of Pasteurellaceae and the other pathogenic microorganisms by the supplier, but Haemophilus infection was detected in these groups by culture and by detection of antibodies against Pasteurellaceae antigens, as described previously pneumotropica pneumotropica G-pig = guineapig; n.d. = not done (Boot et al 1994(Boot et al /95, 1995(Boot et al , 1996(Boot et al , 1999. The API NH, cell wall lipid profiles and some serological properties of the Haemophilus strains present in the rats and guineapigs have been described (Boot et al 1996(Boot et al , 1999.…”

Rat strains differ in antibody response to natural Haemophilus species infection

“…All sera were assayed by ELISA for antibodies to V-factor requiring Haemophilus strains H21 and H35 and P. pneumotropica NCTC 8284, which are our antigens used for routine monitoring of rats for Pasteurellaceae infection. This panel of antigens was based on studies on the serological relationship of rodent Pasteurellaceae (Boot et al 1994(Boot et al /95, 1995(Boot et al , 1998. Phenotypic characteristics appearing from API NH testing and cell wall lipid pro-filing suggested that the Haemophilus strain H21 (API NH code 7766) (Boot et al 1994/95) might belong to the H. parainfluenzae complex; and strain H35 (API NH code 7720) (Boot et al 1998) seemed to be related to H. aphrophilus/paraphrophilus, which was confirmed by 16S rDNA sequencing studies (unpublished).…”

“…This panel of antigens was based on studies on the serological relationship of rodent Pasteurellaceae (Boot et al 1994(Boot et al /95, 1995(Boot et al , 1998. Phenotypic characteristics appearing from API NH testing and cell wall lipid pro-filing suggested that the Haemophilus strain H21 (API NH code 7766) (Boot et al 1994/95) might belong to the H. parainfluenzae complex; and strain H35 (API NH code 7720) (Boot et al 1998) seemed to be related to H. aphrophilus/paraphrophilus, which was confirmed by 16S rDNA sequencing studies (unpublished). P. pneumotropica NCTC 8284 is a biotype Jawetz strain (Frederiksen 1981, Boot et al 1995.…”