Improving the growth rate of Kienyeji chickens can be achieved through various management practices, including:

1. Feeding a balanced diet: Feeding the chickens a diet that is rich in protein, vitamins, and minerals can help to promote rapid growth. A balanced diet can be achieved by providing a combination of grains, vegetables, and protein-rich feeds such as insects, worms, or fish.
2. Providing clean water: Access to clean, fresh water is crucial for the growth and development of Kienyeji chickens. Ensure that the birds have access to clean water at all times.
3. Proper housing: Providing a clean, comfortable, and spacious living environment can help to reduce stress and promote growth in Kienyeji chickens.
4. Disease management: Preventing and controlling diseases through proper vaccination and good hygiene practices can help to reduce stress on the birds, allowing them to focus their energy on growth.
5. Use of growth-promoting supplements: The use of growth-promoting supplements such as probiotics, prebiotics, and enzymes can help to improve the growth rate of Kienyeji chickens.

It’s important to note that while these practices can help to improve the growth rate of Kienyeji chickens, it’s also important to follow recommended management practices and not to push the birds beyond their natural growth capacity, which can lead to health problems and reduced productivity.