NONGENETIC FACTORS INFLUENCING GROWTH AND FLEECE TRAITS IN AFRINO SHEEP

Data, consisting of 4235 lamb records, obtained from the Foundation Af rino Sheep Stud at the Carnarvon Experimental Station, were used to in vestigate factors influencing birth weight, weaning weight, monthly bo dy weight from five to 12 months, body weight at 18 months of age as w ell as clean fleece weight and mean fibre diameter at 16 months of age . Year/season of birth, sex and birth/rearing status of the lamb as we ll as age of dam and age of lamb were significant (P < 0.01) sources o f variation for clean fleece weight and body weight at all ages. Mean fibre diameter was significantly (P < 0.01) influenced by year/season of birth, sex and age of lamb. Significant (P < 0.01) two-way interact ions were found between year/season and sex and year/season and weanin g status. Least-squares means (kg) for body weight were 4.84 +/- 0.04 at birth, 29.55 +/- 0.31 at weaning, 39.27 +/- 0.41 at eight, 52.32 +/ - 0.52 at twelve and 54.13 +/- 0.55 at eighteen months of age. For cle an fleece weight and mean fibre diameter, least-squares means of 2.01 +/- 0.09 kg and 21.47 +/- 0.09 micron were recorded. The results are c ompared to those reported in the literature.