Do you want to test layers or broilers? How are the conditions in your experimental facility? What size of differences between experimental groups do you expect and what difference should be proven to be significant? Check Poultry journals to find out how others have tackled these problems and what results they have obtained. You can find two papers on large broiler trials in my research list.

Dear colleague

it could be nice to focus in the scientific problem you are trying to solve, depending on the proposed hypothesis it will be the experimental set up.

best regards,

Redimio

Do you want to test layers or broilers? How are the conditions in your experimental facility? What size of differences between experimental groups do you expect and what difference should be proven to be significant? Check Poultry journals to find out how others have tackled these problems and what results they have obtained. You can find two papers on large broiler trials in my research list.

Each replicate (the experimental unit) may be individual birds, but more often is made of pens from five to more than 1,000 birds. https://extension.uga.edu/publications/detail.html?number=B1417&title=Pen-size%20Optimization%20Workbook%20of%20Experimental%20Research%20Design%20(POWER%20for%20Poultry)

Kindly check https://www.nature.com/articles/srep46074

Also check http://www.fao.org/3/a-y5169e.pdf

Dear colleagues,

Thank you very much for your responses.

عاده يتم تقسيم إعداد الطيور الى معاملات وتكراراتويفضل ان يوضع في كل تكرار من١٢_١٥ طائر اذكان افراخ ومن ٦_٨ إذا كان امهات

Dear colleague Fikrineh Negash

The number of repetitions are subject to the experimentation conditions, having said that, you must know what is a repetition, what is an experimental unit, what is an observation and what is a treatment, which are included within the experimental design. The number of repetitions per concept must be sufficient to reduce the standard error and variability within the experimental groups and so logical that it allows human experimental work, I give you a simple example that you can extrapolate to your real condition:

You have two treatments (A, and control), establish four repetitions per treatment and twenty observations per repetition, it means that you must take 80 measurements for each variable you consider, which, although it reduces the experimental error, increases the time of sampling and the human resources to achieve it, including in other errors, such as: exhaustion of the personnel that supports in the taking of samples, extension of the time in the taking of samples, generates stress in the birds, complicates the measurements, all this increases the error to despite having a statistically robust number of repetitions and observations.

I hope I've been helpful