الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A study was carried out to evaluate genetically maternal performance traits in New Zealand White (NZW) and Californian (Cal) rabbits in terms of number born alive (NBA), litter size at each of birth (LSB), 21 days (LS21) and weaning (LSW), litter weight at each of birth (LWB), 21 days (LW21), and weaning (LWW), mean bunny litter weight at each of birth (MBB), 21 day (MB21), at weaning (MBW), litter gain at each of 21 days ( LG21), weaning (LGW) and pre-weaning mortality (PWM). The studied traits were estimated from records of 956 litters in NZW and 490 litters in Cal rabbits in such evaluation. Data were separately analyzed for each breed using Mixed Model of the Least squares and Maximum Likelihood computer program (Harvey 1990) to obtain least square means for fixed effects (parity, season and year) for each breed and single-trait animal model to estimate heritability, repeatability, and permanent environmental effects for those aforementioned traits.
General means of litter size and litter weight traits in NZW were higher than that in cal. CV% of litter size and PWM traits were higher in Cal than in NZW. Effect of parity order was significant in each of LSB, LS21, LW21, LWW, MBB, MB21, LG21, LG and MWP traits in NZW and in each of LWB, LWW, BBW, and LG traits in Cal. Effect of season of kindling was significant on each of LSW and LG traits in NZW and on each of LWW, LG21 and LG traits in Cal. Effect of year of kindling was significant on each of LSW, LWW, LG21 and LG traits in NZW.
Heritability estimates ranged between 0.01 to 0.15 while the repeatability estimates were ranged from 0.07 to 0.27 for all traits studied in NZW and Cal rabbit breeds, respectively. Permanent environmental effect estimates ranged from 0.1 to 0.15 in both breeds studied.
In general, estimates of heritability, repeatability, and permanent environmental effects were low or moderate in the two breeds studied.