The success or failure of a broiler breeder flock is often dictated by pullet management. A key indicator of rearing success is flock uniformity. A uniform flock will respond to photostimulation in a uniform way as indicated by a high peak production (>88%) and persistence of lay (≥10 weeks over 80%). Having a consistent feeding program throughout the growth period is key to achieving acceptable uniformity and benefiting from all the characteristics of a uniform flock (Table 1).

From placement to the onset of lay, there are several key segments of pullet rearing (Figure 1).

Key Segment 1: Growth and Development

Early feeding programs are not just about weight gain — flock uniformity is greatly influenced at this stage. However, uniform feed intake can be challenging in newly placed chicks due to the natural characteristic of the bird toward feed consumption time or aggression toward feed intake. This can create wide variations among chicks early in weight and body confirmation. Therefore, at placement, feeding chicks using the appropriate number of supplementary feeders (maximum of 75 chicks/tray) or spreading feed out on paper for uniform access allows chicks to eat on demand. It is not so much about the volume of feed as it is the accessibility of feed for everyone simultaneously.

Although the first key segment is focused on chick growth, adapting chicks to controlled feeding is also very important for the remainder of rearing and onward through production. To move chicks toward controlled feeding, begin to remove supplementary feeders after day 7 and work to have all removed by day 10. If using paper, the feed should be consumed within 48 to 72 hours to control waste.

 An important aspect of controlled feeding is getting the correct amount of feed distributed evenly throughout the house while allocating enough feeder space for all birds to have equal access to feed at the same time. Be familiar with the timing of feeder space changes as the pullet grows (see our progressive feeder space recommendations in the Cobb Breeder Guide). Insufficient feeder space can cause uniformity problems as timid birds are outcompeted by aggressive eaters. However, with excessive feeder space, there may not be enough feed to distribute throughout the system, causing uneven feed distribution. This is especially important when practicing a feeding program where small volumes of feed must be evenly delivered daily.

 Key Segment 2: Controlled Growth

 The second key segment of pullet rearing, controlled growth, is focused on controlling and maintaining bodyweight. Feed allocations and weighing and fleshing of birds must be monitored weekly to maintain the correct weekly gains to achieve the bodyweight standard. Cobb recommends following our bodyweight standards for successful results, but some companies have developed their own standards based upon their success. Regardless of the standard, strict focus should be placed on achieving targets. Regularly monitoring weights and fleshing and adjusting feed allocations will help achieve high flock uniformity. To help with this, here are some things to consider during feeding:

  • Ensure the hoppers are charged prior to the feeding process.
  • Use designated auger heads for each feed line especially on multiple line pan systems (see photos below).
  • Manage hopper depth gates on chain and trough systems to help with feed distribution.
  • Ensure consistent pan opening settings.
  • When using faster chain speeds (27 meters to 36 meters/minute or 90 to 120 feet/minute), try to distribute all the days feed in one round. This takes correct feed space to achieve later in the flock and as feed volumes increase.
  • Complete initial feed distribution in the dark to ensure the system is full, reduce stress, and keep the birds as quiet and calm as possible.
  • Use signal light when feeding, especially on a chain feeder, to help correctly distribute the birds.  Signal lights are proven to improve uniformity and reduce flock nervousness at feed time reducing injury and animal welfare conditions. This method trains the flock to associate the signal light with feeding time instead of associating feeding with personnel. Speak to your local Cobb technical representative for more details on a successful signal light program.
  • Without segregation/sorting pens within a rearing house, flock distribution can be challenging at feed time. Using signal lights or feeding in the dark helps spread the flock out evenly throughout the house, so the feeding system is occupied uniformly once the lights are turned back on.  Some operations control their feed systems from a work room outside the flock space so no one needs to enter the flock space prior to feeding to help with anxious flocks at feed time.

Once feed is distributed around the entire system, the lights are turned on and caretakers can enter the building to ensure everything is running correctly.

Regularly monitoring weights and fleshing and adjusting feed allocations will help achieve high flock uniformity. To accomplish this, use designated auger heads for each feed line, especially on multiple line pane systems. Above, a view of outside the house, and below, inside the house. | Cobb-Vantress


Key Segment 3: Acceleration of Bodyweight

In this phase, consistent and increased weight gains are needed to not only manage body conformation but also reproductive system development. This weight gain will allow the females to develop the desired fleshing and sexual uniformity to maximize peak egg production and maintain post-peak persistence. Although consistent weight gain is important during this phase, pullet fleshing scores are more important. The objective of the accelerated growth phase is to provide enough fleshing and fat reserves to last the hen through peak production.

We often use the term “turn up” during this period as a focus on how much bodyweight percentage was gained from 16 to 20 weeks of age. This is a great indicator of whether or not feed and feeding were managed correctly to achieve what the flock needs to perform in the production period. Typically,   a minimum of 34 % turn up in bodyweight from 16 to 20 weeks is the goal. More than 34 % (within reason) is not detrimental to the flock, but falling under the 34% threshold will often lead to poor performance and desired results.

Other Considerations of Pullet Feeding

Technological advances in feeding systems and management of house environments have innovated pullet rearing to the point where fewer caretakers are used to conduct flock management. While these new technologies are great and allow us to focus more on animal welfare, pullet growth, correct feed distribution, etc., with less manual labor, it can create some challenges in the needs to address equipment failures in a timely manner. New technology never replaces someone at the farm managing the feeding process.

Observe and document how fast flocks clean up their feed each time they are fed. Feed cleanup time is defined as the amount of time it takes for the flocks to consume all the feed presented at feeding, measured from the time it begins to be distributed into the house until it is all consumed from the feeding system. This normally means that the chain in the trough is clearly visible as well as the bottom of the trough with only a little leftover feed between the feed chain links. Feed cleanup time can serve as an indicator of flock uniformity issues. Monitor feed cleanup time and use it as a troubleshooting tool.                

Everyday Feeding

Our business is always evolving, and this includes our feeding practices. One area that is seeing some attention currently is in every day (ED) pullet feeding. Although this makes maintaining flock uniformity more challenging, it is something that needs to be understood. Consider the following to manage ED feeding with limited feeder space and aggressive consumption:

  • Grade and sort pullet flocks into similar groups.
  • Increase chain speeds to 36 meters/minute (120 feet/minute) or higher.
  • Manage hopper flow gates (chain feeders) so all the feed is out in one loop of the chain (see photo 2; need faster chain speeds for this).
  • Run feed lines with the daily feed allocation before lights on.
  • Practice presentation feeding — raise, fill, and lower feeder every day.
  • Manage the pan system by adjusting the number of lines and pan settings.
  • Bulk up feed to get more volume.

These are just a few suggestions, and more details can be provided from your local Cobb tech representative.

To manage everyday feeding with limited feeder space and aggressive consumption, manage hopper flow gates (chain feeders) so all the feed is out in one loop of the chain (need faster chain speeds for this).


It is difficult for a Cobb breeder flock to achieve true reproductive genetic potential without managing the Cobb standard for weight and fleshing. Responsible feed management with the correct feed specifications from hatch to photostimulation will help achieve this goal. Ideally, every pullet at the time of transfer will be very similar, with weight and fleshing between 98% and 102% of standard. Reality is a little less perfect, so using proactive feed management to achieve maximum flock uniformity should lead to the reproductive success of your flock.