The Effect of Procaine Penicillin and Ascorbic Acid on Egg Weight and Shell Thickness During Hot Weather

Abstract

IT IS generally known that eggs laid by chickens when air temperatures are high have thinner, more easily broken, shells than have those laid when air temperatures are low or moderate. Experimental evidence of this was apparently first reported by Bennion and Warren (1933), who observed that when hens were kept under high temperatures their egg shells seemed more fragile.Conrad (1939) reported that the thinning of egg shells under high temperatures was associated, or at least coincident, with a decrease in the blood calcium level of the laying chicken. In the same experiment, Warren and Schnepel (1940) obtained data showing a considerable reduction in the thickness of the egg shells of hens when their constant environmental temperature was raised to 90 degrees F.In those experiments, calcium carbonate was used in the diets of the layers as the main source of calcium. In two experiments where different principal sources …