Czech study shows coarse limestone to produce better eggs

Bigger limestone particles prove to have better effect on laying hens and the egg shell strength, according to the Institute of Animal Science in Czech Republic.

A total of 120 ISA Brown hens aged 24 - 36 weeks and 120 ISA Brown hens aged 56 - 68 weeks were used to study the influence of limestone particle size and the animal's age on laying performance and egg quality.

Two diets were used: a diet containing calcium carbonate in fine limestone particles (diet LF with limestone particles <0.5 millimetres), and a diet containing calcium carbonate in coarse limestone particles (diet LC with 91% of particles larger than 0.8 millimetres and smaller than 2 millimetres).

It can be concluded that LC with a particle size of 0.8–2 millimetres should be considered rather than fine ground limestone when formulating diets for laying hens both in the early and the late phase of production.