EFFECTIVENESS OF INDIRECT SELECTION FOR EGG CHARACTERISTICS USING CERTAIN PLASMA CONSTITUENTS IN THREE LOCAL BREEDS OF CHICKENS

Abstract

This work aimed to evaluate the effectiveness of the indirectselection by using certain plasma constituents at 8 and 12 weeks ofage to achieve an advantageous change of the target productivetraits in three local breeds of chickens: Dandarawi (Dand),Fayoumi (Fay) and Golden Montazah (GM). Breed significantly(P≤ 0.01) affected plasma constituents regardless of age ofmeasurements. Fay had significantly higher PG and PTC thanother breeds (200.65 and 108.20 mg/100ml) whereas GM had thelowest PTC of 88.91mg/100ml. Dand had the highest PTP being6.38mg/100ml. Age of measurements significantly affected eitherPTP or PTC while, its effect on PG was insignificant. Higher PTPat 12 than 8 weeks of age was shown whereas the PTC wassignificantly higher at 8 weeks of age than 12 weeks of age (6.46vs 5.69 and 109.79 vs 96.94 mg/100ml, Table 1). Significant breedby age of measurement interaction (P≤ 0.01) effects on PG, PTPand PTC were found. There were inconsistent breed differenceseither in magnitude or direction in the expected correlatedresponses in egg production-related traits and each of clutch sizeand pause traits to future selection. Therefore, plasma constituentsat 8 and 12 weeks in Dand, GM and Fay can be used as selectioncriteria to improve their productive performance. So, the morethan unity efficiencies indicated indirect selection for targetproductive traits through selection for plasma constituents atcertain studied ages which was more efficient than the directselection for improving these traits. However, direct selection forproductive traits will be the most efficient method for improvingthese traits if their efficiencies were lower than unity.