Today’s layer flocks live for about 90 weeks. Despite the rearing phase only accounting for a small proportion of the birds’ life cycle, it plays an important role in subsequent egg production.
Good rearing management is more than just following breeding company guides. Those working with birds must also pay attention to flock condition and behavior, and make decisions based on observation. What the pullet rearer sees on a daily basis is often overlooked, yet it is one of the most important factors in successful pullet rearing.
Preparing the chicken house
Isolation and restricted access to the brooding area are of prime importance to control and prevent poultry diseases. The all in-all out program is recommended, as it provides an excellent means of isolation, and allows proper cleanup should a disease occur.
Movement between the rearing area and lay houses should be avoided.
Only place day-old chicks in properly cleaned and disinfected houses, and ensure the house is at 36C when chicks arrive. Litter should only be placed once the floor is at the correct temperature. Should there be significant differences between floor and room temperature, and if litter is unevenly spread, condensation can make the litter sticky.
The first week can be termed the brooding period. Post-hatch, chicks are cold-blooded for the first five days of life, unable to maintain their body temperatures at 40-41C, and dependent on external heat sources. Consequently, air temperature is among the most important factors for successful rearing. Using an infrared thermometer, chick body temperature can be monitored, and the house temperature adjusted as necessary.
But crucial mistakes are often observed in the poultry house:
- Reference thermometer not at chick level. At 50 cms above chick level, there can be a temperature difference of 2-3 C
- Behavior ignored. Looking at the thermometer is not enough, chick behavior must also be closely watched. Some flocks are comfortable with 34C during the first 24 hours, others need 26C. Chicks should be evenly spread throughout the barn. If huddled, they are cold, while if inactive with spread wings they are too warm.
- Air humidity. To ensure heat distribution across the poultry house, and to prevent chicks dehydrating, air humidity must be at least 60 percent. If not, chicks will feel uncomfortable, despite the temperature being correct. Humidity is easily improved, for example through moistening areas where chicks are not present, or by hanging wet sheets.
It is also worth remembering that drafts will chill chicks and lead to piling.
On arrival, chicks have already endured a long transportation period. For day-old chicks, it is normal to have 24-hour lighting for the first 2-3 days, allowing them to recover and to eat and drink ad libitum.
However, while some chicks rest after arrival, others seek out food or water; flock activity will always be uneven. At this stage, it can be difficult to accurately assess chick behavior and condition. An intermittent lighting program can be used over the first 7-10 days post-hatch. This divides the day into resting and activity phases, and aims to synchronize chick activity to make it easier for staff to assess flock condition and to stimulate food and water intake through group behavior.
The benefits of using an intermittent program are:
- Chicks rest or sleep at the same time and behavior is synchronized
- Weaker chicks are stimulated by stronger ones to be active and ingest feed and water
- Behavior becomes more uniform, making assessment easier
- Week one losses are reduced.
Once the program has been used for 10 days, the rearer can adopt the breeding company recommended lighting program.
Feed and water
Poultry growers should aim to feed and water day-old chicks as quickly as possible on arrival to minimize first week mortality. The sooner they eat, the better they metabolize the yolk sack nutrients, lowering the risk of yolk sack infection.
There must be enough space between feeders and drinkers and, after veterinary consultation, electrolytes can be added to the water. Keeping the water temperature at 22-25C aids water intake.
Feeding best quality mash or crumbled feed is not recommended during this period. Only non-saturated fatty acids, such as linoleic acid, can be utilized by the chicks and should be added to the feed.
Four diets – starter, grower, developer and pre-layer – during the brood/grow period are adequate for chicks/pullets. Each should be supplemented with vitamins and minerals and should be fed until breeding company target weight is achieved.
The main mistakes seen in rearing house are:
- Nipple drinkers too high. During the first days, they should be at the chick eye level. Chicks must be able to operate the nipples easily, so water pressure must be low.
- Too few drinkers and feeders. Birds should not have to search for feed and water. Birds that do not drink do not eat.
- If birds arrive beak trimmed, open water sources, for example round drinker cups, must be available.
- Water in round drinkers must be regularly changed and lines flushed. Pipes must be thoroughly cleaned and care taken to ensure no disinfectant residues taint the drinking water.
- Incorrect water temperature. Water temperature should be 22-25C.
- Feed and water are sometimes placed many hours or days prior to chick arrival, leading to dry feed and water that is too warm. This can slow growth and increase first week mortality.
- If pan feeders are incorrectly adjusted, birds over 12 weeks of age may selectively eat, leading to the incorrect supply of nutrients.
- Using different drinker and feeder systems at rearing and production can contribute to starvation and the dehydration of pullets post-transfer. Never use open water sources and chain feeders when you transfer pullets to the production house if only nipple drinkers and pan feeders are installed.
- Supply feed with the correct particle size for each age. Very young birds do not like feed that is too fine.
Body weight is more important than age when changing feeding phase, and changes should not be made before target weight is reached.
Bird weight is an important indicator for applying management tools. Frequently observed errors include:
- Weighing without drawing conclusions.
- Weighing too few birds; 1 percent of the flock, or at least 100 birds per flock, should be weighed.
- Not weighing birds at all.
Remain alert to possible distress signals from chicks, and react to the following behaviors:
- Listless and prostrate chicks indicate excessive heat
- Loud chirping suggests hunger or cold
- Grouping or huddling together indicates cold or drafts
- Pasted vents, which may indicate excessive heat or coldness or feed containing unbalanced fatty acids.
When rearing pullets, management guides are indispensible, but instinct tells us a lot too. A climate computer may indicate optimal conditions, but if flock behavior does not look right, then the reason needs to be found. A little time investment can pay dividends and increase the rearer’s sensitivity to the flock.