The influence of birth#x2013;rearing rank, dam age,and live weight on hogget traits and lambing performance are described for 15 731 Romney ewe hoggets recorded in the Department of Lands and Survey Romney Breeding Scheme over 5 years (1972amp;#x2013;1976).Two#x2013; year old lambing performance of the 8 157 hoggets retained in the years 1973#x2013;1977 was investigated for effects of previous lambing as a hogget. Dam age and birth#x2013;rearing rank effects were present in all hogget traits#x2014;lamb weaning weight, September (yearling) live weight, hogget fleece weight, and hogget fertility. The greatest handicap in all traits was experienced by later#x2013;born hoggets out of 1#x2013;year#x2013;old dams. Hogget lambing percentage (lambs weaned per hogget mated) varied from 11.6amp;#x0025; to 46.2 between years. Single#x2013;born hoggets out of 1#x2013;year#x2013;old dams had a mean lambing percentage of 18.7 compared to 36.7 for hoggets out of 2+#x2013;year#x2013;old dams. The corresponding figures for twin#x2013;twin hoggets are 12.0 and 31.5. Lamb survival rate averaged 77.6, and was consistent across years and between dam age and birth#x2013;rearing rank classes. Multiple births were low at 3.7. The relationship between percentage of hoggets lambing and yearling live weight was sigmoid but varied between dam age classes. Two#x2013;tooth ewes that had reared lambs as hoggets reared more lambs at two#x2013;tooth lambing owing to decreased barrenness and progeny mortality. Hogget fleece weight was reduced by 0.1 kg in hoggets that lambed.
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