Long-term growth of laying hens begins before hatching, a process that cannot be influenced by pullet breeders and egg producers. The moment the newborn chicks arrive at the breeding hall plays a key role in the development of the birds. The productivity of a herd depends to a large extent on the successful achievement of body weight at an early age.

Goals during the breeding period (pullet) are:

Rapid growth to reach the ideal body weight in 5 weeks
Good uniformity at the beginning of the production cycle
Excellent livability

From the beginning to the time of transfer to production halls, birds will grow slowly and limb development will occur at different ages. Lack of growth during any of the stages can have a detrimental effect on the quality of the pullet.

Any delay in growth at 4 to 5 weeks of age leads to weight loss at 16 weeks and performance, especially the average egg weight in temperate climates. Please note that two birds with the same body weight have not necessarily developed to the same extent.

A key rule: a good growth curve leads to the evolution of the currency.

Growth can be divided into the following stages:

The first 3 weeks are dedicated to the development of organs and the immune system
From week 3 to week 6, skeletons and muscles are growing
Body weight at 5 or 6 weeks is an important determinant of the quality of the pullets. Any delay in growth at this stage is harmful to birds. As it will have a detrimental effect on the quality of the coin and body composition, it will therefore have a negative effect on the performance of the birds.
From 6 to 15 weeks, growth begins slowly.

The final stage is marked by the development of the ovaries and the rapid growth of these organs. The regulation of sex hormones occurs around 18 weeks and leads to puberty at this age.

Figure 1. Evolution of body weight

Preparing for the arrival of chickens

Success in breeding largely depends on a good start for the chickens. Most chickens that have traveled for some time are looking for a place where water, food and a good environment can rest. Here are some key points:

Halls must be clean and disinfected and empty for at least 14 days. Halls and contents must be dry before the chickens arrive.
Turn on the heating system 24 to 36 hours before the chickens arrive (depending on weather conditions). At the time of arrival of the chickens, the environment of the hall and bed should be warm enough and the constant temperature should be in the range of 33 to 35 degrees Celsius.
Align the drinking lines before the chickens arrive. Do not disinfect drinking lines before the chickens enter.
Make sure the nipples and round watering cans are at the right height, the nipples should be on the bed at the level of the chicken eye and the round watering cans.
Check the water supply system used to see if there is enough water. When the nipples are used, adjust the water pressure so that the chicks can see the water droplets on the nipples and the water can flow easily in the slightest contact.
Spread the cardboard under the nipples and pour some food on the cardboard or cardboard trays to absorb the chickens.
Routine all birds, even in minor cases that have access to water and food.
After long journeys, it is very helpful to make sure that the birds have enough water to return their body fluids for 3 to 4 hours before feeding.
Use lukewarm water at 25 to 30 degrees Celsius for the first two days.
Be careful in hot conditions and do not allow the water temperature to rise as it may reduce the feed intake of the chickens. Adjust the drinking lines to maintain a regular temperature.
Monitor the amount of water consumed.
Avoid spilling water on the chickens as this will preserve the quality of the litter.
Always keep your drinking water clean for the first two weeks. They should be cleaned at least daily.

Keep your chickens warm

In order to ensure that the webster equipment is warm for the chickens to enter, it is recommended that you start raising the room temperature at least 36 hours before the chickens arrive so that the air temperature reaches 33 to 35 degrees Celsius.

The concrete floor should be at 28 ° C and the bed temperature at 30 ° C. The best way to check if the room temperature is correct in the first few days after entry is to measure the temperature of the chicken coop (40 ° C).

It is recommended to take the temperature of at least 20 chickens from the whole hall to get a good impression of the situation. Chickens can not regulate their body temperature, so they depend on environmental conditions. Note that the body temperature of chickens reacts quickly to changes in environmental conditions.

Find the correct temperature setting point by adjusting the body temperature of the chick. Check the chicken’s body temperature every hour after being placed in the room. Check Rata’s body temperature when the correct temperature is not reached and the position is not fixed. On the fifth day, the chickens are normally able to maintain their body temperature, and the body temperature will automatically rise to about 41 degrees Celsius.

From there, the room temperature adjustment point can be gradually reduced to about 20 degrees Celsius in 5 weeks (for example, half a degree Celsius per day). Temperature standards are given in Table 1, but again observing herd behavior is the best indicator of the actual needs of chickens.

Table 1. Temperature and humidity standards

Age (days)	Broading temperature (degrees Celsius)		Hall temperature	relative humidity
	Near heating temperature	Temperature 2 m distance from the heater		Suitable-Maximum (%)
3-0	35	28-29	33-35	60-55
7-4	34	27-28	31-32	60-55
14-8	32	26-27	28-30	60-55
21-15	29	25-26	26-28	60-55
24-22	–	23-25	23-25	65-55
28-25	–	21-23	21-23	65-55
35-29	–	19-21	19-21	70-60
بعد از 35	–	17-19	17-19	70-60

If the chickens are gathered together, it means that the temperature is too low.
If the chickens are far apart and inactive, the room temperature is too high.

At all stages, the uniformity of the herd should be checked. The goal is that the high uniformity is to help manage and stimulate the herd. Low uniformity leads to poor spawning performance. The number of feeders, feeders, feed distribution, feed availability and farm management can be very helpful in ensuring herd uniformity. Heterogeneity at a young age has a negative effect on uniformity during transition.