Improved Kienyeji chicken refers to local chicken breeds that have been selectively bred for improved traits such as higher productivity, disease resistance, and better growth rates while maintaining their desirable local characteristics. Here are some types of improved Kienyeji chicken:

1. Rainbow Rooster: This breed is a hybrid of Kuroiler and Rhode Island Red breeds, and it is known for its excellent egg production, meat quality, and fast growth.
2. KARI Improved Kienyeji: This breed was developed by the Kenya Agricultural Research Institute (KARI) and is a cross between indigenous breeds and commercial breeds. It is a dual-purpose breed that is suitable for both meat and egg production.
3. Kuroiler: This breed was developed in India, and it is a cross between Rhode Island Red and Cornish chicken breeds. It is known for its fast growth, high meat yield, and excellent egg production.
4. Kenbro: This breed is a hybrid of Kuroiler and Rhode Island Red chicken breeds. It is a fast-growing and hardy bird that is suitable for both meat and egg production.
5. Sasso: This breed is a French breed that has been developed for both meat and egg production. It is known for its excellent meat quality and is resistant to many common poultry diseases.
6. Indigenous chicken: These are local breeds that have been improved through selective breeding. They are well adapted to the local environment and are known for their resistance to diseases and parasites.

Each of these breeds has its unique characteristics and is suited to different environments and purposes.