Effect of Dietary Fossil Shell on the Quality of Hen's Egg Shell in Summer

Abstract

Effect of dietary fossil shell on improving the quality of hen's egg shell in summer was investigated. One hundred and twelve white Leghorn inbred cross layers were fed experimental diets from 19th June to 8th October 1973. Experimental diets were formulated to provide 16.1 per cent crude protein and 3.5 per cent calcium, and contained 90.47 per cent basal diet and the remainders were calcium sources. Calcium sources were provided by 0, 1.56, 3.13 and 4.69 per cent fossil shell and by 6.66, 6.09, 5.46 and 4.84 per cent calcium carbonate, respectively and cellulose powder was used to make up 100 per cent. The basal diet contained yellow corn 61.4, milo 11.0, wheat bran 4.3, fish meal 7.5, soybean meal 10.1, alfalfa meal 3.2 and vitamin and meneral mixture 2.5 per cent.Egg production rate, thickness of egg shell, egg weight and body weight gain of experimental hens showed similar values in all experimental groups. Food consumption of hens fed fossil shell diets showed higher (about 3 gram per bird day) values than that of hens fed calcium carbonate alone diet.Average determined egg shell strength of hens fed 4.69 per cent fossil shell showed 0.23 higher than that of hens fed calcium carbonate alone diet. When the egg shell strength of the experimental period were compared with the values of pre-experimental period, all hens showed lower values in summer, but dietary fossil alleviated the adverse effect of summer on the egg shell strength.