Reproductive performance, growth and wool production of Romanov sheep in Canada

Abstract

Performance of 14 Romanov ewes imported from France in 1980 and their 100 Canadian-born progeny over a period of 5 years is reported. Ovulation rate was 2.5±0.06 and 3.0±0.15 for 7 to 10-month-old and older ewes, respectively. Least-square means for fertility were 100% for ewes mated in the autumn and winter and 42% for those mated in summer. Age and weight of ewes at first lambing were 372 days and 46 kg, respectively. Corresponding figures for second and third parity lambings were 656 days, 56.5 kg and 902 days, 59.8 kg, respectively. Average interval between lambings was 276±9.5 days. It was shortest (248 days) when the following mating was in autumn and longest (308 days) when in summer. Fifty-one percent of 41 ewes on an accelerated lambing management succeeded in lambing three times in 24 months and the rest required 28 or 32 months. Litter size at birth (2.86±0.15) and at weaning (2.10±0.15) were significantly affected by season of mating and parity. The most prolific matings were those of the autumn and of ewes in their fifth parity (3.18 and 3.54 lambs, respectively). On the average, 0.52 (18.2%) lambs died at birth and an additional 0.25 lambs (8.7%) before weaning. Total litter weight averaged 7.1 kg at birth (6.0 kg alive) and 39.0 kg at weaning. Average birth weight of lambs born alive was 2.9 kg. Body weights at 70, 180 and 365 days of age were 17.8, 34.5 and 47.6 kg for females and 20.0, 41.1 and 59.2 kg for male lambs, respectively. Preweaning average daily gain was 217 g for females and 245 g for males. Productivity, evaluated by total weaned lambs at 70 days per ewe per year, was 39.9 kg for yearlings and 54.9 kg for older ewes. Greasy fleece weight ranged from 1.1 kg for 7 to 9-month-old lambs to 2.5 kg for 44 to 49-month-old ewes. The performance of this first sample of Romanov breed in North America was high and generally comparable to that in Russia, France and other European countries.