EFFECT OF FEEDING SEASON ON REPRODUCTIVE AND PRODUCTIVE TRAITS OF EWES AND SUCKLING LAMBS

This paper aims to investigate feeding season effect (winter and summer) on reproductive and productive traits of the ewes and suckling lambs. Biological investigations were conducted on 60 Merinolandschaf breed ewes aged 4 years on the average and their lambs (123) in the suckling-ablactation period. In the winter feeding season ewes were fed grain mixture (300 g daily) containing 60% oats, 30% maize and 10% soybean meal as well as hay (ad libitum). The lambs were suckling and they received forage mixture, quality hay and fresh water ad libitum. During the summer feeding season ewes grazed on the pastures. The lambs were suckling and received forage mixture, quality hay ad libitum and pasture green mass in smaller portions. While comparing winter to summer feeding season the ewes had longer gravidity period (150.76 and 150.40 days), more lambs at parturition (1.21 and 1.11) and ablactation (1.10 and 1.07), more twins (12 and 8), higher body weight during gravidity (65.52 kg and 61.86 kg) and increased body weight losses after lambing (7.72 kg and 6.44 kg). As for the body weight losses after lactation (7.94 kg and 7.78 kg) no statistically significant differences were determined between the feeding seasons. Birth weight of lambs was higher by 26.91% (4.15 kg and 3.27 kg) and at 60 days of age it was higher by 11.40% in winter compared to summer feeding season. Faster daily gains of lambs (by 7.21%) was determined during the winter feeding season. However, it was noticed that lambs aged from 40th to 60th and 20th to 60th day obtained higher daily gains (by 6.25% and 1.74%) in summer feeding season.