Divergent selection for response to sheep RBC in guinea fowl

High titre (HAb) and Low titre (LAb) lines for response to sheep RBC, were developed in guinea fowl after four generations of selection. Eight sires were used in S1 generation as well as in subsequent generations. Each sire was mated with four to six dams. Response to SRBC was measured as microtitre haem-agglutination titre and expressed as log₂ of the highest dilution in which there was complete haemagglutination. After the second generation of divergent selection, significant differences between lines mean HA titre were observed and subsequent generations of divergent selection sustained these differences between the lines. In general, a declining trend was observed in selection differential, which suggest decreasing variation for HA titre in the lines. Divergent selection was effective in bringing significant differences between HAb and LAb line for response to SRBC.