Histophilosis, or Histophilus somni–associated disease, is a common disease in North American cattle. It also has been reported to occur sporadically in beef. Histophilus somni is a Gram-negative bacterium that is associated with a disease complex (termed histophilosis) that can produce several clinical syndromes. Histophilus somni (H. somni) is a Gram-negative bacterium currently classified as a member of the Hae- mophilus-Actinobacillus-Pasteurella group. Clinical.

Author: Kazralkis Shakree
Country: Lesotho
Language: English (Spanish)
Genre: Technology
Published (Last): 15 June 2014
Pages: 426
PDF File Size: 9.59 Mb
ePub File Size: 2.76 Mb
ISBN: 394-3-67038-918-2
Downloads: 18108
Price: Free* [*Free Regsitration Required]
Uploader: Meztikree

Pneumonia in bighorn sheep: This organism has also been isolated from tonsillar and reproductive tract samples from American bison Mathematical model for studying genetic variation in terms of restriction endonucleases. Although thrombosis of blood vessels was not seen, sizeable sonni masses were present in lymphatic channels in the histopholus septa. In previous studies, we found histophi,us bovine isolates varied in ability to lyse bovine erythrocytes, whereas none of the isolates from domestic sheep produced hemolysis Biochemical characteristics and biovariant types of the Haemophilus somnus isolates.

Banding patterns were used to calculate indices for the relationship between all isolates The multiple similarities in RFLP profiles of the bighorn isolates and their distinct differences from those of the domestic-livestock isolates demonstrates that the bighorn-sheep isolates are more closely related to one another than they are to domestic-livestock isolates.

Immunohistochemical study with antibody specific for H.

From reactions in H. Although all hishophilus 1 of the bighorn isolates and 2 of the domestic-sheep isolates produced identical biochemical utilization reactions that were characteristic of biovariant 4, the bighorn-sheep isolates lacked the yellow pigmentation and CO 2 requirement of the domestic-livestock isolates.

Antigenic profile with Western blot testing of the isolates after exposure to convalescent-phase serum from 2 calves with experimental Haemophilus somnus infection.

There was a problem providing the content you requested

The authors thank all individuals who assisted with the capture of bighorn sheep and the collection and timely submission of samples evaluated in this study. Polymerase chain reaction PCR Isolated DNA from each of the isolates was tested in a PCR procedure for the lktA histophilue, which codes for leukotoxin production and has been demonstrated by Fisher et al 23 to be associated with production of hemolysis on blood agar by Pasteurella and Mannheimia strains.


Prevention of the H. However, the reverse situation may be more complicated: Isolation of Histophilus ovis from vaginal discharge in ewes in Canada. Identification and source of Haemophilus somnus isolates in the United States and Canada in this study.

Haemophilus somnus recently reclassified as Histophilus somni is associated with hixtophilus disease in American bison, domestic sheep, and cattle. Antimicrobial sensitivity profiles were similar for all the isolates and correspond with those reported elsewhere for H. From studies of 68 clinical cases of bovine pneumonia positive only for H.

Select a Country zoetis. Lack of these cardinal characteristics, as described for domestic-livestock isolates 10could result in lack of detection and identification of the organism.

The bighorn-sheep isolates of H. Selective culture media is needed to ensure growth of the bacteria and samples should ideally be taken from untreated animals. Although colonization of the prepuce is common in domestic livestock 36colonization was not detected by culture of any of the 12 samples collected from bighorn rams.

Therefore, the expression of these antigens by the bighorn-sheep isolates suggests that they may be virulent. Isolate identification a Geographic location Animal species; b anatomic site Associated clinical condition A. Proposal of Histophilus somni gen. The gel was stained for 1 h with 50 parts per million of ethidium bromide J.

National Committee for Hisotphilus Laboratory Standards, We previously showed that antibodies to this OMP protected against experimental H. If calves are to be vaccinated it should be performed prior to entry into the feedlot. A kDa antigen was present in the 3 domestic-sheep isolates 67P,LB and the virulent bovine isolate but not in the bovine preputial carrier isolate Pt. As noted previously 25the relative molecular weight rMW of the MOMPs of bovine preputial isolate Pt, approximately 33 kDa, was much lower than that of most of the other isolates.

Histophilus somni (Haemophilus somnus) Complex | Zoetis US

Oxytetracycline has been effective in the treatment of TME when the drug is given at the onset of clinical signs. Pasteurella spp in sympatric bighorn and domestic sheep. Evidence of pulmonary congestion and edema may be noted as well. Colony pigmentation, hemolytic activity, and CO 2 requirement of the Haemophilus somnus isolates. Nathan Ahlemeyer, Class of -edited by Dr. Reproductive tract swab samples were collected from 74 desert bighorn sheep Ovis canadensis nelsoni captured in southern Nevada as part of a health-monitoring program.

  AS NZS 3788 PDF

Technical considerations for developing enzyme immunohistochemical staining procedures on formalin-fixed paraffin-embedded tissues for diagnostic pathology. The bacteria require a breakdown in mucosal immunity in order to cause disease. Protective ability of antibodies against and kilodalton outer membrane antigens of Haemophilus somnus. Morphological, biochemical, antigenic, and cytochemical relationships among Haemophilus somnus, Haemophilus agni, Haemophilus haemoglobinophilus, Histophilus ovisand Actinobacillus seminis.

Colonies of Gram-negative bacteria may be seen in thrombi. The profiles of major outer membrane proteins and antigens for all of the isolates were predominantly similar, although differences that may be associated with the host—parasite relationship and virulence were detected. Most of the previous reports have presented information related to the isolation of H. Colonies characteristic of Pasteurellaceae were further tested. Bacterial meningitis and encephalitis in ruminants.

Microthrombi were detected in alveolar septa of most of the lungs, and 3 lambs had occasional vascular thrombi in the brain. Clinical disease can be devastating when it occurs. In other studies of bovine pneumonia with a d experimental period, Jackson et al 36 found that mild vasculitis was detected only occasionally. The strains with low amounts could have low expression, or the IgBPs may have been shed from their surfaces. Others have shown that H.

Field trials to test the efficacy of the vaccine are difficult to perform due to an inability to consistently recreate the disease process.