<div style="text-align:justify">Back ground: India has a huge resource of livestock and stands first globally in milk production, but reemergence of diseases like foot and mouth disease (FMD) causes a great concern and economic losses to the farmers. Three serotypes of FMD virus (O, A and Asia 1) are prevalent and serotype O was responsible for 80 per cent of confirmed outbreaks /cases in India. The highest incidence of the disease was seen in Southern region (31.5%) and during the month of September. Highest number of outbreaks (201) occurred in Tamil Nadu in the year 2007-08 caused by serotype O virus. FMD causes very high morbidity and mortality rate among young animals and the mortality rate is generally low in adult animals and seen with manifestation of infection limited to epithelial sites. However, In the present study an unusually high mortality among adult cattle due to FMD, complicated with Mannheimia hemolytica infection with specific myocardial lesions were discussed in several outbreaks of FMD in the state of Tamil Nadu, India. Methods: Outbreaks of FMD occurred in various districts of Tamil Nadu during the period of October to December in the year 2013 causing large scale mortality among adult cross bred (Jersey cross and Holstein Friesian cross) cows, heifers and calves and detailed disease investigations were carried out .Samples were collected from ailing animals and dead animals for laboratory confirmation of the disease. The collected samples were subjected to isolation of bacteria, serology and molecular confirmation of the virus. Result: Affected animals showed characteristic lesions of FMD with multiple, focal to coalescing ulcers and erosions covered with shreds of epithelium and fibrin on the dorsum and lateral margins of the tongue, dental pad, hard palate, mucosa of lips and gums. Samples of vesicular fluid, oral and tongue epithelium and heart confirmed the presence of FMD type &lsquo;O&rsquo; virus based on sandwich ELISA and multiplex PCR. Cultural examination of bacteriological samples revealed presence of Mannheimia hemolytica which was further confirmed by multiplex PCR. Out of 83 serum sample collected, 45 sera were positive for FMD by LPB ELISA, while 32 serum samples were positive for FMD by DIVA test. The sudden deaths among adult cattle and heifers during the FMD outbreak might be attributed to the severe myocarditis and the disease was controlled by following appropriate treatment and preventive measures.</div>

<div style="text-align: justify;">A Report on Massive Outbreaks of FMD with Concurrent Mannhaemia hemolytica Infection among Cattle in Tamil Nadu</div>

Background:&nbsp;Mannheimia is a Gram-negative, facultative anaerobe, non-spore forming and non-motile bacteria belongs to the family Pasteurellaceae. Caprine bacterial pneumonia is most often caused by Mannheimia haemolytica (previously known as Pasteurella haemolytica) and Pasteurella multocida which are more frequently associated with the outbreak of acute pneumonia and death of goats, particularly young once. Mannhemia is an opportunistic pathogen that particularly inhabits the nasopharynx and tonsils of goat and sheep. The present study was aimed to study Mannheimiosis in Guwahati, Assam in order to diagnose and control the disease among goats. 
 
Methods: The present investigation was conducted during the year 2021-2022 in Guwahati, Assam. A total of 51 pneumonic lung samples were collected from nearby slaughter houses and during necropsy at Department of Pathology, C.V.Sc., A.A.U., Khanapara, Guwahati-22. All the samples were subjected to primary isolation in blood agar and MacConkey&#39;s agar and further confirmation was made using PCR. 
 
Result: Out of total 51 pneumonic lung samples examined seven (13.72%) cases were found positive for Mannheimia haemolytica infection where 5 cases were found to be associated with other respiratory pathogens.&nbsp;Visible gross lesions observed during necropsy were broncho-interstitial pneumonia, suppurative pneumonia and fibrinous pneumonia with hemorrhagic tracheitis. Histopathological examination revealed presence of characteristic oat cells, intravascular thrombosis, fibrin balls, oedema, necrosis and polymorphonuclear cell infiltration in the lungs. Bacteriological culture for isolation and identification of Mannheimia haemolytica showed &beta; haemolytic zone on MLA plates. Confirmatory diagnosis was made using PCR targeting 16s rRNA gene with amplicon size 1500 bp and Lkt gene with amplicon size 206 bp. The phylogenetic analysis of 16s rRNA gene from positive sample showed percent identity of above 97% with other strains of Mannheimia haemolytica present in NCBI website. The variability in the lesions observed in the present study it can be concluded that a mixed infection with reduced resistance of the animals contributed to the development of pneumonia rather than Mannheimia haemolytica alone and PCR can be used as reliable technique for confirmatory diagnosis of respiratory mannheimiosis.

A Report on Massive Outbreaks of FMD with Concurrent Mannhaemia hemolytica Infection among Cattle in Tamil Nadu

Pathomorphological and Molecular Studies of Respiratory Mannheimiosis in Goats