The start of layer breeding goes to 1962 when the first layer hybrid called Moravia (mix of LB and RIR line) was bred and reproduced in Školní zemědělský podnik Žabčice (School Agricultural Company). The two original lines were imported from Alexander Angell company. In 1973 and 1974 three other clean source lines were imported from Babcock company in England. Based on two Bar Plymouth Rock lines and one Rhode Island Red line the final hybrid B-390S was produced. For B-380 hybrid production two other synthetic lines were imported. In the half of eighties, the hybrids were sold under the trade name Moravia SSL (brown variety) and Moravia BSL (black variety) which has been sold till nowadays.

The breeding work of Moravia complex programme is focused to farms in Práče and Bantice, Czech Republic, where 10 original clean lines have been reared currently. Moravia BSL is popular and widespread especially in conditions of traditional technologies because of its unpretentiousness and high quality of egg production. The significant advantage is an excellent adaptability, vitality and low mortality in rearing and production as well. This black layer is very popular among farmers for its exceptional cream colour of eggshells.