Models of Contagious Bovine Pleuropneumonia: Evaluation of Two Novel Strains

Abstract

The clinical course of infection following endobronchial inoculation of three strains of Mycoplasma mycoides subspecies mycoides small colony (MmmSC), the causative agent of Contagious Bovine Pleuropneumonia (CBPP), was compared in 15 mixed-breed Bos taurus steers. Two of these strains have not previously been investigated under experimental conditions. The cattle were inoculated endobronchially with MmmSC strain Gladysdale, Ondangwa or Shawawa and monitored for 42 days. Four of five Gladysdale-inoculated cattle developed acute clinical CBPP. Four of five Ondangwa and 3/5 Shawawa-inoculated cattle developed subacute to chronic CBPP without overt clinical signs but had characteristic pathological lesions. MmmSC was isolated from cattle both during the course of infection and at necropsy. Clinical signs and necropsy lesions were consistent within groups. Ondangwa and Shawawa strains of MmmSC may be useful for study of subacute and chronic CBPP, which is more common in natural infection than peracute CBPP. Use of recent strains will enhance study of CBPP host response, pathogen detection and vaccine development.

Epidemiological and pathological screening of suspected cases of contagious bovine pleuropneumonia in Yola Modern Abattoir, Adamawa State Nigeria

“…Pathological lesions during CBPP infections are generally restricted to the thoracic cavity, usually one lung and pleura are affected and a large volume of pleural exudates containing clots of fibrin (Fischer et al, 2012;OIE, 2018). Large fibrin deposits make the lung adhere to the chest wall and at these sites, the pleura is thickened and opaque (Gull et al, 2013). The interlobular septa of affected lung regions are also thickened due to adsorption of the exudates and "frame" the lung lobules, which vary in colours of red, grey and yellow due to different stages of inflammatory lesions giving the characteristic "marbled" appearance (Olorunshola et al, 2020).…”

Transboundary Animal Diseases, an Overview of 17 Diseases with Potential for Global Spread and Serious Consequences

“…Mice develop mycoplasmaemia following infection, but they are not a good model of the pathology seen in CBPP [285,288]. Cattle models are costly and can present difficulties reproducing disease, but several challenge techniques have been developed [240,241,[288][289][290][291]. Contact infection studies resemble natural infection but require an extra group of diseased animals and result in an unpredictable rate and timing of transmission, making it difficult to compare disease outcomes [290,291].…”

“…Contact infection studies resemble natural infection but require an extra group of diseased animals and result in an unpredictable rate and timing of transmission, making it difficult to compare disease outcomes [290,291]. Endobronchial inoculation of three different strains of Mmm in steers showed two strains (Ondangwa and Shawawa) may be useful for study of subacute and chronic infections, while the third (Gladysdale) more closely mimics the peracute form of disease [289]. Nkando et al presented nasotracheal inoculation of cattle with the aid of a bronchoscope as an alternative to an endobronchial intubation approach where tube insertion requires sedation of the animal [290].…”