Author
Beier, Ross | |
Byrd Ii, James - Allen | |
Kubena, Leon | |
Hume, Michael | |
McReynolds, Jackson | |
Anderson, Robin | |
Nisbet, David |
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/12/2013 Publication Date: 1/28/2014 Citation: Beier, R.C., Byrd II, J.A., Kubena, L.F., Hume, M.E., McReynolds, J.L., Anderson, R.C., Nisbet, D.J. 2014. Evaluation of linalool, a natural antimicrobial and insecticidal essential oil from basil: Effects on poultry. Poultry Science. 93:267-272. Interpretive Summary: Linalool is a natural plant product used in perfumes, cosmetics, and flavoring agents. Linalool has proven antimicrobial and insect repellant properties, which indicate it might be useful for control of enteropathogens or insect pests in poultry production. However, there are no published reports that linalool may be safely administered to or tolerated by chickens. We added linalool to the diets of day-of-hatch chicks and fed linalool-supplemented diets for three weeks. We studied the effects of linalool on serum chemistry, gross pathology, feed conversion, and relative liver weights. Feeding levels at or below 2% linalool showed no negative effects on the chickens. No gross pathology, significant changes in feed conversion, or treatment effect on relative liver weights was observed. There was a statistical effect on blood glucose, but remained below the elevated cut-offs for elevated serum glucose, and this result is likely of no biological significance. Linalool caused serum aspartate aminotransferase (AST) levels to increase at high linalool levels, but at doses of 2% linalool or below, AST was not elevated beyond normal parameters. No dose dependent increase was observed in alanine aminotransferase (ALT), an enzyme which is recommended as an indicator of hepatocellular injury. It is concluded that linalool, in modest doses, may be safely added to chicken feed, and low levels necessary for reduction in insect infestation and also for producing a calming effect should be well tolerated. Technical Abstract: Linalool is a natural plant product used in perfumes, cosmetics, and flavoring agents. Linalool has proven antimicrobial and insect repellant properties which indicate it might be useful for control of enteropathogens or insect pests in poultry production. However, there are no published reports that linalool may be safely administered to or tolerated by chickens. We added linalool to the diets of day-of-hatch chicks and fed linalool-supplemented diets for three weeks. We studied the effects of linalool on serum chemistry, gross pathology, feed conversion, and relative liver weights. Linalool had a dramatic negative dose-dependent effect on feed conversion at concentrations in the feed exceeding 2% linalool, but not on gross pathology. Serum levels of calcium and phosphorus were decreased in birds receiving the highest doses of linalool. There was no treatment effect on relative liver weights. There was a statistical effect on blood glucose, but this parameter remained below the cut-offs for elevated serum glucose, and this result is likely of no biological significance. Linalool caused serum aspartate aminotransferase (AST) levels to increase. The linalool effect on AST was dose dependent, but in modest linalool doses (0.1–2% of feed) AST was not elevated beyond normal parameters. It is concluded that linalool, in modest doses, may be safely added to chicken feed, and low levels necessary for reduction in insect infestation and also for producing a calming effect should be well tolerated. |