Effects on body temperature produced by micro-injection of Salmonella typhimurium lipopolysaccharide into the third cerebral ventricle of the chicken.

Salmonella typhimurium lipopolysaccharide was injected into the third cerebral ventricle of the hen via a surgically implanted cannula. Hens injected with 20-80 mug. Salmonella typhimurium lipopolysaccharide had higher (P less than .01) rectal temperatures (42.3 degrees C. compared to 41.3 degrees C.) than uninjected hens. Those injected with 0.9% NaCl had significantly lower (P less than .01) rectal temperatures (41.8 degrees C. compared to 42.3 degrees C.) than hens injected with this bacterial pyrogen. There is an indicated function for bacterial pyrogen acting directly in the hypothalamic area of the chicken.