Culture-positive persistence and serum agglutinating antibody response after intrauterine inoculation of Haemophilus somnus in virgin heifers.
Viable Haemophilus somnus of reproductive tract origin (OSU-1167) was inoculated transcervically into the uterus of 6 virgin heifers. Five heifers were sham-inoculated (intrauterine) with sterile mycoplasmal medium and served as controls. After inoculation and observation, all heifers had nasal and vaginal vestibular swab specimens and serum obtained periodically for 44 days. Signs of systemic illness were not detected. On the day after inoculation, all inoculated heifers had signs of vulvovaginitis, whereas none of the control heifers had similar signs (P less than 0.002). Haemophilus somnus was not isolated from any nasal or vaginal vestibular swab specimens obtained before inoculation or from any nasal swab specimens obtained after inoculation. During the 44 days after inoculation, H somnus was isolated from 25 of 54 vestibular specimens obtained from inoculated heifers and from 3 of 45 specimens obtained from controls (P less than 0.02). Vulvovaginal lesions were associated with vestibular isolation of H somnus in 23 of 25 (92%) such isolations from inoculated heifers; lesions were never associated with concurrent isolation of H somnus in controls. All heifers had H somnus microagglutination test (MAT) titer less than or equal to 256 against a commercially prepared H somnus antigen at the beginning of the study. Considered as groups, neither inoculated nor control heifers achieved fourfold increases in MAT titer during the 44 days after inoculation. When compared by day of sample collection, inoculated heifers did have significantly (P less than 0.04) lower geometric mean titer at 7 days after inoculation than did control heifers when tested by use of a commercially prepared antigen.(ABSTRACT TRUNCATED AT 250 WORDS)
Hoblet
K H
KH
Department of Veterinary Preventive Medicine, Ohio State University, Columbus 43210.
Haibel
G K
GK
Kowalski
J J
JJ
Rojko
J L
JL
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000382:microbiology*; D005260:Female; D006190:Haemophilus / Q000254:growth & development / Q000276:immunology / Q000302:isolation & purification*; D006192:Haemophilus Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D009297:Nasal Mucosa / Q000378:metabolism / Q000382:microbiology; D013997:Time Factors; D014621:Vagina / Q000382:microbiology*; D014848:Vulvovaginitis / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*
D000907:Antibodies, Bacterial