Abstract
Twenty growing female Damascus (Shami) goats and twenty growing Chios ewes of two mating ages (10 and 12 months) were used to study the effect of mating age (MA) on reproductive performance (RP). In addition to (RP), The growth, milk production and nutrient requirements were also evaluated. A complete random design in a $2{\times}2$ factorial was used, with (MA) and species as the main factors. (MA) had no effects on (RP), milk production and mortality. No significant difference (p > 0.05) were observed between (MA) or between species, for age at kidding/lambing (K/L). Sheep reached puberty earlier than goats. Average age (months) at conception and at (K/L) was 15.8; 20.8 and l7.0; 22.0 for sheep and goats respectively. Body weight (BW), rather than age was the most important factor determining puberty. Both goats and ewes conceived when they reached about 67% of their mature (BW) for goats and 85% for ewes. Sheep grew faster than goats, but the latter had higher twinning (67.8% versus 25%). Chios sheep were suitable for meat and Shami goats for dairying or dual purpose systems. Nutrient requirements for growth of goats and ewes were similar with an average DM-intake of about 4% (BW); 12-13% CP and 65-69% TDN (DM-basis) of the total ration. It is recommended to breed Chios ewes at a (BW) of at least 50 kg and Shami does at 38 kg, irrespective of their age.