Background: Escherichia coli cause mammary gland inflammation in dairy cows with striking local and sometimes severe systemic clinical symptoms. This disease affects many high producing cows in dairy herds and may cause several cases of death per year in the most severe cases. The present study was planned to evaluate the antibiogram and virulence factors of the isolated bacteria responsible for mastitis.&nbsp; 
 
Methods: In this study, 300 milk samples were collected and subjected to identify clinical mastitis (based on clinical symptoms) and sub clinical mastitis (using California mastitis test). E. coli was isolated and identified from mastitis positive samples and further tested for antibiogram and virulence factors such as haemolysis, biofilm formation and fimH and pap genes presence. 
 
Result: Out of 300 milk samples collected, 121 (40.33%) were positive for mastitis. E. coli was isolated from only 30 (24.79%) out of 121 mastitis positive samples. On Serotyping for somatic antigen, 13 E. coli isolates belonged to somatic serogroup O83, 2 to O157 and one each to O8, O20, O49, O119, O128 and O145. The highest sensitivity of E. coli isolates was recorded for ciprofloxacin, followed by gentamicin, tetracycline, nitrofurantoin, chloramphenicol, amikacin, cefixime, trimethoprim, ampicillin/sulbactam, ceftriaxone, cefoperazone, cefotaxime, kanamycin, cefotaxime/clavulanic acid and amoxycillin in the decreasing order. Multidrug resistance (MDR) was recorded in 96.66% of isolates.&nbsp;Out of 30 E. coli isolates, 46.66% were haemolytic and 40.0% positive for Congo red dye binding. Biofilm production was shown by 76.66% isolates. Molecular characterization revealed presence of fimH gene in 9 isolates, but pap gene was not detected in any of the strain. It may be concluded that E. coli is an emerging environmental mastitogen in cows and isolation of MDR strains with virulence factors is of serious concern.

Antibiogram, Haemolysis and Biofilm Properties of Escherichia coli from Bovine Mastitis

<div>Background: E. coli associated buffalo mastitis is comparatively least studied area in microbes in India. Mastitis is an inflammatory reaction of the parenchyma of the mammary gland that can be of an infectious, traumatic or toxic nature.&nbsp; 
 
Methods: Total 300 buffalo milk samples were collected. E. coli were isolated from the mastitis samples and characterized for virulence factors haemolysis, biofilm formation, invasiveness and molecular characterization of fimH and Pap Gene. 
 
Result: Out of total 300 buffalo milk samples 52.33% were found positive for sub clinical mastitis. E. coli was recovered only from 17.19% samples. Hemolytic activity was exhibited in 23 (85.18%) out of 27 examined E. coli strains. Invasive property also has been determined in 12 (44.44%) isolates. A higher percentage of isolates were found positive for biofilm production by CRA (70.37%) than by tube (33.33%) method. In present study, fimH gene was detected in 8 isolates (29.62%). However, none of the isolate was found positive for pap gene.</div>

Virulence Determinants of Escherichia coli Isolated from Buffalo Subclinical Mastitis

<div>Background: Avian colibacillosis is considered as major cause of morbidity and mortality in poultry. It is a common bacterial disease of poultry and many virulence factors of E. coli are associated with the disease. The current study was aimed to investigate the presence of some virulence factors of E. coli isolated from the cases of colibacillosis. 
 
Methods: In present study, total 150 samples (liver, heart, lungs, air sacs and feaces) of chicken exhibiting pathological conditions of colibacillosis were collected from various poultry farms (organized and backyard) situated in and around Mhow and Indore cities. E.coli was isolated and identified from the samples on the basis of cultural characteristics and biochemical test. All E. coli isolates were further subjected to evaluate the presence of virulence factors such as biofilm production, haemolysis, invasiveness and molecular detection of fimH and stx1 gene. 
 
Result: Out of these 51.33% of incidence of E. coli was recorded. E. coli O84 and O149 serotypes were found most prevalent. Out of 77 isolates, 46 (59.7%) and 45 (58.4%) were positive for biofilm formation by tube method and modified CRA method, respectively.&nbsp;All E. coli isolates were showing invasiveness in congo red binding assay while none of the isolates was found haemolytic. Molecular detection revealed the presence of fimH (508bp) gene in 33.3% of tested samples while stx1 gene could not be detected in any isolates.</div>

Antibiogram, Haemolysis and Biofilm Properties of Escherichia coli from Bovine Mastitis

Virulence Determinants of Escherichia coli Isolated from Buffalo Subclinical Mastitis

Studies of Virulence Factors of Avian Pathogenic Escherichia coli in Avian Colibacillosis by In vitro Method and PCR