Trace minerals in poultry nutrition - 5: Reaching optimal egg shell formation

摘要

An egg - produced either for production or consumption - is not just an egg. For either of these purposes, there are many similarities for which both environmental as well as nutritional factors greatly influence the formation of a strong and good shell. What is the function of the eggshell? Well, to some extent it depends on the destiny of the egg. If it is the product of the layer bird, then its prime function is protection against microbial penetration and so it must be intact, free from blemishes, and clean. In terms of size, the larger egg must, like the family sized cornflake box, represent value for money, but unlike the cornflake box, egg size does influence shell quality. Shell colour, too, enters the equation and in the classic example ofthe book being judged by its cover, brown evenly pigmented shells will be purchased before their paler neighbours.