Evaluation of β-Exotoxin of Bacillus Thuringiensis Berliner for Control of Flies in Chicken Manure

Publisher Website
Google Scholar
Abstract
A calcium and a sodium salt of β-exotoxin obtained from Bakthane-L69® were added to rations supplied to hens and to pullets. This exotoxin was too toxic to be fed to chickens for the control of the house fly, Musca domestica L., droppings. Not more than 3 mg/kg per day could be fed to hens for a week. The oral LD50 to pullets was ca 1 mg/kg per day. Both salts were toxic to chickens, the calcium salt at 20 ppm in feed and the sodium salt at 20 ppm in feed or in drinking water. Toxic symptoms were loss of vigor, reduced feeding, and undersized eggs. Reduced feeding was not a consequence of palatability. The exotoxin caused severe gizzard erosion, then enteritis and proventriculitis. The exotoxin degraded when manure liquified and lost the ability to kill house fly larvae under such conditions. House flies became resistant to the β-exotoxin. After a 6-month selection on media treated with the calcium salt, the larvae tolerated media containing 600 ppm.

This publication has 0 references indexed in Scilit: