CROSSBREEDING EFFECTS OF PROGENY TRAITS DUE TO CROSSING OF BAUSCAT AND BALADI RED RABBITS

A crossbreeding study was carried out at the Experimental Rabbit Farm,




Department of Animal Production, Faculty of Agriculture, At-Azhar University, Nasr




City Cairo, Egypt, for three consecutive years of production starting from September




1998, using Bauscat (exotic breed) and Baladí Red (local breed) ¡n addition to their




two reciprocal crosses to study direct heterosis, maternal additive and diret additive




effects on progeny traits (body weight and daily gain). Breed group effects on body




weight were non-significant at different stage of ages, while its effects on daily gain




weight were found to be significant at age intervals of (8-10), (10-12), (12-14) and (4-




14) weeks of age. Threr was a superiority of Bauscat rabbits over Baladi Red for body




weight at studied all age except at 10 weeks, while for daily gain weight ¡t was during




all age intervals except at (5-10) weeks. however the differences between the two




breeds were mostly non-significant for body weight and daily gain traits.




Crossbreeding between Bauscat and Baladi Red rabbits was generally associated




with improvement in all body weights and daily gain weight traits except body weights




at 12, 14 weeks and daily gain during ages intervals of (8-10), (10-12) and (4 —14)




weeks. Direct Sire additive effect on progeny traits were mostly ¡n favour of Bauscat




sired rabbits progeny traits except body weight at 14 weeks and during the age




interials of (8-10), (10-12), (12-14), (birth-14) and (4-14) weeks it was in favour of




Baladi Red sires. Maternal additive effect on progeny traits was in favour of Baladí




Red rabbits for most studied body weight traits. When crossbreeding was applied




between these two rabbit breeðs Maternal additive effect on daily gain was ¡n favour




of BR dams during the age intervals of (birth-4), (4-6) and (6-8), while daily gain




during intervals of (8-10), (10-12), (12-14), (birth-14) and (4-14) weeks were in favour




of B dams.




Keywords: Egyptian Balad Red rabbits, crossbreeding, Heterotic effect,




maternal additive effect, direct additive effect.




INTRODUCTION




Crossbreeding has an advantage over the synthesis of breeds ¡n




utilizing the breed differences due to the expected segregation along with the




recombination (Dickerson, 1969). Egyptian studies (e.g. Afifi, 1971; Afifi and




Khalil, 1989; Oudha, 1990; ElDessokì, 1991; Afifi et aL, 1994; Khalil et at,




1995 and Abd El-Aziz, 1998) evidenced, ¡ri general, that crossing local




breeds of rabbits (e.g. Baladi, Baladi Red, Baladi Black, Giza White, ..etc.)




with exotic breeds (e.g. Bauscat, Californian, New Zealand White, ... etc.)




was associated with improvement in progeny traits ( e.g. body weight and




daily gain weight). Several studies were carried out to investigate the




productive potentialities of native and exotic breeds of rabbits under the




Egyptian conditions, in spit of this results there is a need to obtain more




information about the genetic, environmental and managerial aspects of




rabbit production to create a profitable industry. In addition to estimate the




present objectives direct heterosis (H’), direct(G5 and maternal (G’) additive