cracking of egg laid by a flock of layers in a farm can be corrected by?

A. addition of iodine to the water supply
B. increasing the level of vitamin D in mash
C. increasing the quality of calcium in mash
D. increasing the amount of calcium, phosphorus and vitamin D in their feed
E. increasing carotene and calcium level of the mash

Correct Answer:

Option D – increasing the amount of calcium, phosphorus and vitamin D in their feed