Effects of Heterosis and Direction of Crossing on Production Performance of F 1 Offspring of Dominant Black Strain and Fulani Ecotype Chickens.

The objectives of this study were to determine the mode of gene action of determinants of performance (i.e. positive or negative heterosis) in F chickens produced by mating  Fulani Ecotype (FE) and Dominant Black strain (DB) chickens, and whether the direction of crossing (DBxFE or FExDB) influenced the mode of gene action. Analysis of all F data  irrespective of cross direction (combined) showed that the effect of 1percentage heterosis was positive but weak for Weight Gain (WG) = 0.04, Feed Intake (FI) = 3.83, Body Weight at First egg (BWF) = 0.76, Egg Weight (EW) = 11.28, and 0 for Egg Number (EN) and Mortality (M) during the laying period. The combined heterotic effects were negative for Hen Day Production (HDP), Feed efficiency (FEf), Age at Sexual Maturity (ASM), and mortality from day old to 21 weeks of age (-0.16, -4.33, -9.15 and -67.74% respectively). Positive but low heterosis was obtained for BWF (0.76), and EW (11.28) and WG, FEf, EN, ASM, HDP and M showed negative heterosis (-100.00 to - 0.28) in the DBXFE cross bred. The mean performance of the FEXDB showed positive heterosis ranging from 1.08 to 100% in WG, FI, BWF, EW, EN, HDP and M during the laying period, while negative heterosis; -67.74, -4.54 and -8.22 was observed for M (0- 21days), FEf and ASM. The reciprocal effects showed F FEXDB were superior in ASM, 1 BWF and EW, while F DBxFE were superior in EN, HDP and M. 1Key words: Exotic laying strain, Fulani Ecotype chicken, Heterosis, Reciprocal effects