Published online by Cambridge University Press: 02 September 2010
The objective of this study was to assess the growth and development of carcass composition of entire male and female lambs of three Greek dairy breeds (Boutsko, Serres and Karagouniko), from weaning to live weights approaching maturity, when kept under conditions designed to be nutritionally non-limiting. Lambs were weaned at 6 weeks of age and given a high quality pelleted food ad libitum until slaughter at one offive different degrees of maturity. As expected, there were significant effects of breed and sex on both food intake and growth rate. The Gompertz growth function was used to characterize, for each genotype, the growth curve and to provide estimates of mature weight and appeared to describe adequately growth rate. For two breeds (Serres and Karagouniko) food intake (g/day) increased in a linear fashion with time up to approximately 24 weeks of age and then remained static for the last 10 to 22 weeks of the experiment; this coincided with the increased environmental temperatures during summer. No such plateau in food intake was seen for the Boutsko sheep. The estimates of mature weight (kg) for the females of each breed were: Boutsko, 60; Serres, 66; Karagouniko, 77. These were substantially in excess (1·4 times on average) of the pre-trial calculations of mature weight. The mature weights of the males were found to be not significantly different from 1·3 times the mature weights of the females. Relationships between carcass composition and weight were derived by allometric regressions. This study provides the first full description of the growth and meat production potential of the three Greek breeds; as such it is part of an overall study that aimed to characterize (for thefirst time as far as the authors are aware) nine sheep breeds from diverse regions of the European Union.