5 th International Poultry Conference 10-13 March 2009. Taba – Egypt 1693 SOME FACTORS AFFECTING OSTRICH CHICK WEIGHT AT HATCH AND ITS PERFORMANCE DURING THE FIRST FOUR WEEKS OF AGE Kh. M. Mahrose* 1 ; H. A. Khalil** and M. E. Mady** *Poultry Dept., Fac. Agric., Zagazig Univ., Zagazig . ** Animal Prod. Dept., Fac. Agric., Suez Canal Univ., Ismailia, Egypt Abstract: Fifty five fertilzed eggs and 55 chicks of African Black ostrich were used in the present study in two trials to examine the effect of laying egg weight )≥ 1350 gm, 1351 - 1450 gm and < 1450 gm(, egg weight loss % )≤ 10%, >10 - < 14% and >14%) during incubation on chick weight at hatch (gm) and incubation period (days) in the 1 st trial, as well as the effect of different photoperiods (14, 16 and 18 hours per day) on chick performance during the first 4 weeks of the age in the 2 nd trial. The results of the 1 st trial showed that egg weighed more than 1450 g significantly )P≤0.05( produced the heavier chicks )883.24 gm) at hatch. Egg weight loss % during incubation and the interaction between laying egg weight and Egg Weight Loss (%) did not affect chick weight at hatch. On the other hand, incubation period (days) did not significantly differ by each of laying egg weight or EWL% during incubation. In the 2 nd trial, using 18 hours of lighting per day significantly )P≤ 0.01) improved each of chick weight (at 3 and 4 weeks of age) and daily weight gain during 2-3 and 0- 4 weeks of age. Feed intake and conversion insignificantly affected due to photoperiods. Correlation coefficients between egg weight and chick weight at the different ages studied had significantly )P≤ 0.01) positive values. Key words: ostrich, egg weight, egg weight loss, chick performance, photoperiod. INTRODUCTION The ostrich industry is growing rapidly in many countries in the world in addition to South Africa, like U.S.A., Australia, Canada, Zimbabwe, Botswana, Egypt, Kuwait and several European countries (Deeming and Ayres, 1994; Sales and Horbanczuk, 1998; Mahrose, 2002; Al-Nasser et al., 2003; Horbanczuk, 2005 and Cooper et al., 2008). Ostrich (Struthio camelus) is the longest and largest of the flightless birds, and have been reared on farms more than 100 years in South Africa for it's valuable products which include feather (1.4 ط1.8 kg of feathers), leather (1.1 - 1.3 m 2 ), healthy red meat (34 ط41 kg), egg production (50 ط120 / season) and ostrich oil (Angel, 1996; Sabbioni et al.,1999, Cooper et al., 2004; Cooper and Horbanczuk, 2005). Recent interest in ostrich farming has led to an increasing demand for information about this bird and how to manage it in a commercial environment (Deeming, 1999 and Minka, 2003). Mahrose (2007) indicated that laying egg weight is the most important factor affecting ostrich chick weight at hatch, whereas chick weight at hatch was significantly (P<0.01) associated (r= 0.914) with laying egg weight. Deeming and Ayres (1994) and Ali (2004) pointed out that there was a significant (P< 0.01) relationship between the percentage weight loss on day 40 of incubation and the weight of the hatched chicks as a percentage of the initial weight of the egg. Ostrich chick rearing is regarded as one of the major areas limiting the expansion of the ostrich industry. R 25