Plant essential oils — an alternative to control salmonella and growth promoting antibiotics for poultry.

The poultry industry has made a major contribution to the food sector of Pakistan, and its products are largely consumed throughout the country in order to meet important protein dietary requirements. However, there is a potential threat of bacterial infections to poultry which result in a huge economic loss. Among the major disease causing bacteria salmonella is present in poultry with or without causing any disease in poultry. When transmitted from contaminated poultry products to human food chain they cause food poisoning and pose a major threat to public safety. Salmonella is the most commonly reported cause of foodborne disease among bacterial infections. Antibiotics are mainly used for the control and treatment of salmonella in poultry industry. Irrational use of antimicrobials in poultry industry results in increased antibiotic resistance and antimicrobial residues get entered in food chain via poultry products. So to control the salmonella prophylactic use of antibiotics in poultry industry solves one problem and cause many others which adversely affect human population as well. The emergence of drug resistance in salmonella is a major challenge. Poultry, especially broiler chickens, can harbor antimicrobial-resistant strains and function as a vehicle for dissemination of these pathogens to humans. It is necessary to search for alternatives of growth promoting antibiotics. In recent years, particular attention has been paid on the use of herbs, spices and the medicinal plants as natural alternatives of the antibiotics.

In current study conducted at Department of Microbiology, University of Veterinary and Animal Sciences, Lahore (UVAS).We isolate 67 salmonella from broilers. Antimicrobial activity of essential oils of medicinal plants i.e cuminum cyminum (safaid zeera), cinnamomumzeylanicum (cinnamon), eucalyptus globulus (safaida), allium sativum (garlic), nigella sativa (black seed) were evaluated in the laboratory against salmonella. Plant essential oils showed good activity against salmonella but best results were given by cinnamomum zeylanicum (cinnamon), and eucalyptus globulus (safaida). These two oils were evaluated in an experimental trial of broiler chicks infected with salmonella. Cinnamon oil and eucalyptus oils were added in bird’s feed from first day of age. We found that these oils especially cinnamon oil reduce salmonella effectively. The birds fed on essential oils mixed feed were remained healthy. Birds supplemented with these essential oils showed higher body weight gain, better immune response and better feed consumption ratio as compared to the other groups which were not provided with essential oils. Although different oils are available in Pakistan but they are not in routine use in poultry feed. This study will insinuate to incorporate oils in poultry feed. The use of these oils may keep poultry safe from salmonella and mitigate its transmission to human food. These plants may prevent the problem of salmonellosis in poultry. Furthermore oil supplementation of broilers may help to minimize the problem of antibiotic residues in meats and eggs.

Sidra Yasmin is a PhD scholar under the supervision of Dr. Muhammad Nawaz at the Department of Microbiology, University of Veterinary and Animal Sciences, Lahore.