1. Introduction

At certain times of the year, especially in summer, the laying may be affected by the presence of high temperatures. This phenomenon is known as heat stress and results in lower egg production and eggshell disorders, associated with lower enzyme activity.

In addition to temperature, another stressful factor that affects layers productive parameters is age. As the age of layers increases, their ability to absorb nutrients decreases and, consequently, the eggshell problems increase.

Therefore, maintaining the correct absorption of nutrients during all the productive stages is essential to ensure the productivity of layers.

Intestinal conditioner pronutrients are active molecules of a botanical origin, which allow to optimize the intestinal physiology, improving digestion and intestinal absorption. They increase mineral absorption at the intestinal level and allow to maintain the parameters of layers in hot environments.

2. Objective

Evaluate the effect of intestinal conditioner pronutrients in layers during hot periods.

3. Material and methods

The trial was conducted with 600-day-old (85 weeks) layers of Boris Brown line. The trial lasted 2.5 months, from August 1^st to October 16^th and during it the temperature ranged from 27-35áµ’C. Intestinal conditioner pronutrients were administered for 47 days, from August 11^th to September 28^th.

Two experimental groups were established, with a total of 20 hens per experimental group:

• Control group: standard diet without any production enhancer
• Pronutrient group: standard diet + intestinal conditioner pronutrients at a dosage of 25 ml/l continuously from 11th August to 28 September.

4. Results

At the beginning of the trial, egg production was lower in the pronutrient group compared to the control group. After the administration of pronutrients, the experimental group obtained a higher egg production compared with the control group.

Table 1. Percentage of egg production obtained during the trial in both experimental groups.

After the period of administration of the pronutrients, the production of egg increased in the experimental group by 6.2%, while in the control group the production decreases.

In relation to egg weight, the control group began the trial with a higher weight per egg compared to the experimental group. However, after the trial, the pronutrient group showed a higher weight per egg, with an increase of 3.17% during the trial. The final difference between both treatments was 0.5 grams per egg.

Graphic 1. Egg weight (g) in the control and intestinal conditioner pronutrients groups.

Regarding the conversion rate, a significant improvement was observed between the two experimental groups during the period of administration of intestinal conditioner pronutrients, with a 4.44% difference

Table 2. Feed conversion rate obtained in both experimental groups during the trial.

No significant differences were observed in relation to shell thickness and egg resistance between the two experimental groups. It is remarkable that although more and bigger eggs are produced in the pronutrient group, which means a higher mineral requirement, no differences in egg resistance were observed between the two experimental groups.

5. Conclusion

The administration of intestinal conditioner pronutrients in layers during high temperature periods improves the status of the intestinal mucosa, and improves the absorption of nutrients, including the absorption of important vitamins and minerals for layers.

This improvement of the physiological status of the intestinal mucosa results in a higher production of eggs (6.2%) and in an increase of egg weight (0.5 grams per egg), without affecting the thickness of the eggshell and the resistance of the eggs. Thanks to a greater absorption of nutrients, the animals are able to produce bigger eggs without affecting the resistance of them.

Intestinal conditioner pronutrients are marketed under the name Alquernat Nebsui of Biovet S.A.