Late production (Up to> 75 weeks)


Eggshell Quality

Body weight at 5–6 weeks of age

The carcass of the hen is mainly developed during the first 5-6 weeks of age. A loss of body weight in this period will reduce the longevity of the layer hen.

Correct use of pre-lay

Incorrect use of pre-lay feed might induce damage to the medullary bone, affecting the capability of the layer hen to utilize Ca from the bone.

Feed intake development using a developer feed

At the start of lay a lack of feed intake will force the layer hen to exert metabolic effort that will compromise the longevity of the hen.

Calcium sources

60–70 % of Ca in the eggshell derives from the diet and 30–40 % from the bones, specially the medullary bone. The availability of Ca during eggshell formation will improve eggshell quality. The midnight snack and particle size and solubility of the Ca sources  are strategies to improve eggshell quality.

Balanced Ca, P and Vit D in diet

Excess or deficiencies will trigger eggshell challenges. 

Use of organic trace minerals

Trace minerals are part of the inner eggshell and in eggshell formation through the enzymes. Use could be justified when, as the egg size increases, the eggshell becomes thinner.


Medullary bone in young hen
Medullary bone in old hen

Good liver health

  • Adding fat and oil or crude fat in layer diets is a well-known tool to reduce the incidence of “fatty liver syndrome”.
  • Added choline chloride in layer diets to support liver metabolism.
  • Methionine and betaine are used to relieve liver metabolism.
  • Vitamins like K’, E, B(), B and folic acid.
  • Mycotoxin control is a must.

List of Mycotoxin

AflatoxinsFatty liver, liver necrosis and bile duct hyperplasia
FumonisinMultifocal hepatic necrosis; hepatocellular hyperplasia
Aflatoxin + T2Pale enlarged liver

Oxidative stress

Physiological stress on the body that is caused by the cumulative damage done by free radicals inadequately neutralized by antioxidant system and that is held to be associated with aging.
  • Free radicals: they are produced during metabolism when ATP is produced, as part of the inflammatory response, heat or cold, stress, high levels of ammonia, oxidized fat in diet.
  • Antioxidant system: it is a complex system involving enzymes, as glutathione dependent of Cys availability or like super oxide dismutase, vitamins and minerals as co factors of the enzymes.
  • Symptoms: unspecific mortality as the hens age and feather loss increases.

Cage fatigue

It is a decalcification of the bones of the hens when there isn’t a balance of the Ca, P and vitamin D in the diet.
  • Ca levels should increase as the birds get older
  • P levels should be reduced as the birds get older
  • Vitamin D deficiency

Improve gut health


Feed hygiene

Try to reduce contamination as much as possible.
  • HACCP quality system to control raw materials and final product quality
  • Addition of additives that can reduce contamination in the feed
  • Don’t forget to monitor the water quality.

Stimulate gizzard activity

The gizzard is the first natural barrier for contaminants in the feed. Increasing its activity will reduce the pH thereby improving the barrier and improving the digestion of nutrients. This reduces the availability of nutrients used for the growth of the pathogens in the lower part of the gut.

Gut health additives

Find the best combination of gut health additives to reduce the growth of the pathogens in the gut. The combination should be based on the area of action, level of pathogens in the area and other challenges.
  • Enzymes; essential oils; organic acids; prebiotics; probiotics
 Mash CFU log/grPellet/crumble CFU log/gr
Enterobacteria<3< 1.5
Escherichia coli<1<1
Anaerobic sulfite reducers at 46 °C<1<1
Molds<3< 1.5
Yeast<3< 1.5

Factor influencing egg size


Methionine is the first limiting amino acid in egg weight. However if we want to control the egg size, we need to do it with the whole amino acid profile so the Ideal Protein Ratio isn’t broken.


There is a minimum requirement of linoleic acid so the egg yolk size isn’t a limitation in the egg size. Need to be careful when raw materials with low linoleic acid are used.


Adding fats, vegetable or animal fats, in the diet increases the egg size. It improves the feed efficiency and reduces the dustiness of the feed


Birds with high body weight (above the standard) at week 5 will produce bigger eggs. It isn’t recommended to have birds below the standard at week 5 (no more than 3 %) to control egg weight in production, performance will be compromised.