Abstract: In order to provide better guide for the construction of the high-quality fattening lambs production system in Ulanqab City, and to compare the breeding economic benefits between Dorper × Mongolian × Suffolk ternary hybrid lambs and local Mongolian sheep lambs under the same feeding and management conditions, a test was conducted to assess the meat production performance of the crossbred lambs. The weight of the crossbred lambs and local Mongolian sheep lambs in different growth period were determined and compared. The results showed that under the same natural environment and feeding and management conditions, the crossbred lambs had higher average birth weight, weaned weight, 5-month-old slaughter weight and 5-month-old average daily gain compared to the local Mongolian sheep lambs. It was demonstrated that promoting the production system construction of Dorper × Mongolian × Suffolk ternary hybrid lambs is one of the effective ways to realize the ecological and efficient breeding in grassland of pastoral areas and to improve quality and efficiency of sheep breeding for farmers and herdsmen.

Key words: Dorper ×, Mongolian ×, Suffolk ternary hybrid lambs, fattening lambs, growth index, economic benefits