South African Journal of Animal Science
On-line version ISSN 2221-4062
Print version ISSN 0375-1589
The objective of this study was to determine the fitness of Quadratic, Cubic, Gompertz and Logistic functions to the growth curves of Konya Merino lambs obtained by using monthly records of live weight from birth to 480 days of age. The models were evaluated according to determination coefficient (R2), mean square prediction errors (MSPE) and Durbin Watson (DW) statistics. The R2 values of the models ranged from 0.96 to 0.99 for females and from 0.96 to 0.99 for males. The Cubic model gave the best R2 value of 0.99 in females, while the Logistic model gave the lowest R2 value of 0.96 in females. The results indicated that the Quadratic and Gompertz models showed the best fit to growth of Konya Merino ewe lambs by having higher R2 values, lower MSPE and non autocorrelation. By using these models live weights at later ages could be predicted from early partial live weight data. Further studies should be carried out on growth curve characteristics at later ages including adult age.
Keywords : Growth; Quadratic; Cubic; Gompertz; Logistic; Konya Merino lambs.