Flock uniformity plays a major role in proper management of breeder flocks. However, within the flock population, natural variations are quite common. With a decreased uniformity, many birds will not be in the same physiological stage of development, and hence will require additional management actions such as light stimulations, feed etc.

Grading is a great way to improve the uniformity of a flock! With grading, the flock is separated and groups of smaller and bigger birds are formed to improve the total flock uniformity.

Let us learn a bit more about grading and how it should be managed.

Importance of Grading

As a biological trait, the flock population will exhibit a natural variation, and the normal distribution of that variable is a bell-shaped curve.



The grading method involves a procedure where the birds which fall under the given mean weight are separated from those birds that are heavy or light (compared to the mean, as they are the extremes of the bird population). This separation allows the heavy and the light birds to be placed in separate pens with an objective of managing their body weights.

Depending on the weight category, the heavy and the light birds are managed by controlling the feed so that they are brought back to the body weight of the average population (which is the mean weight). Grading is usually done between 28-35 days of age and the weight management of the extreme bird population is expected to be completed by the end of the rearing period, 19-22 weeks.

Grading Methodologies

During grading, the different weight categories that the birds are graded into mainly depends upon the farm owner’s choice of measuring flock variation.

Using the uniformity calculation, all the birds that are 10% lighter and 10% heavier than the average mean weight should be kept in separate pens, each. If the CV% method is used, depending on the average, and the CV%, the grading cut off points are decided.

Once the birds are graded into separate populations and moved into different pens, they will remain there until they reach the target body weight. Controlling the body weight is handled by making adjustments to the feed levels.

The birds are expected to reach the target weight by 63-70 days, and if they fail to do so, regrading will be necessary. The birds which are still underweight or overweight by this time, will be managed until 105 days.

Challenges for Grading

Grading is often seen as a herculean task. Add to that the misconception that it involves too much work for a very little return, and there are numerous reasons why farm owners do not want to grade their flock.

  • Increased costs due to more labor.
  • Stressful for birds to move between the pens.
  • Feeder & drinker configurations.
  • Managing feed times.

Such challenges can be eliminated by using a comprehensive poultry management software, which will play a major role in managing multiple pens and keeping a tab on every required parameter.

With the expansion of the poultry industry, farm owners have looked further in detail about ways to improve the hatching eggs and the chick output. With increased research, what we know is that, one certain way of increasing the overall performance is by maintaining flock uniformity. A well graded flock is bound to be more predictable, easier to manage and more profitable in nature. Combine this with the extensive features that a seasoned poultry management software offers, farm owners will start managing a flock with much greater production potential.