Shalini Thakur’s research while affiliated with Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya and other places

Artemisia nilagirica is an important medicinal plant found to exhibit several medicinal properties but the use of its leaves for combating E. coli infection has not been scientifically validated in poultry. The present study was conducted to evaluate the protective effects of methanol leaf extract of A. nilagirica (ANE) on E. coli challenged broiler chickens. Three hundred and thirty, day-old broiler chickens, were divided into 6 groups of 55 each, with group EX infected intraperitoneally (I/P) with LD 50 dose of 1 × 10 7 cfu/ml of E. coli; group(s) EA1, EA2 and EA3 infected I/P with 1 × 10 7 cfu/ml of E. coli and supplemented with ANE @ 0.5, 1.0 and 2.0 g/L of drinking water, respectively; group AX were only given ANE @ 2.0 g/L in the drinking water. ANE treatment was started from day 4 and was continuously given in the drinking water up to day 21. E. coli infection was given to the birds on day 7 of their age. The effect of the plant extract was evaluated on the basis of gross, microscopic and ultrastructural alterations in E. coli challenged broiler chickens. The extract of A. nilagirica was found to show antibacterial, cardioprotective and hepatoprotective properties in a dose-dependent manner on the basis of gross and microscopic examination. The methanol extract of A. nilagirica leaves revealed no toxic effect on the hepatocytes on ultrastructural evaluation. This study demonstrates the antimicrobial, hepatoprotective and cardioprotective activities of ANE in broiler chickens infected with E. coli organism.

The present study was designed to check in vitro efficacy of different medicinal plant extracts against selected animal and poultry pathogens. We have used 20 different plant extracts to screen their antimicrobial activity against Escherichia coli, Salmonella Gallinarum and Salmonella Typhimurium. For this investigation we have prepared plant extracts in different solvents i.e. Hexane, Chloroform, Ethanol, Methanol and Aqueous. Among all extracts, Artemisia nilagirica showed maximum 13mm zone of inhibition against E. coli (O119) and S. Typhimurium. Moreover, Ajuga parviflora, Tinospora cordifolia methanolic extracts and Cissamplelos pareira chloroform extract showed zone of inhibition of 10mm, 11mm and 7mm, respectively. Valerian jatamansi hexane and chloroform extract showed zone of inhibition of 8mm against E. coli only. Zingiber chrysanthum (rhizome or flower), Rubus sp., Pistacia integerrima, Calotropis procera, Grewia disperma and Plantago lanceolata showed activity against all microorganisms. However, Viola canascens, Persicaria nepalensis and Prunus cerasoides showed no antimicrobial activity. In the antibiotic susceptibility testing it was found that E. coli (O119) showed maximum susceptibility for Chloramphenicol followed by Enrofloxacin and Cefalexin, whereas exhibited resistance against Oxytetracycline and Amoxycillin. These findings provide scientific evidence for the development of antimicrobial agents in this era of increasing antibiotic resistance.