Behavior of lambs and ewes of the Polish Merino and Wrzosówka breeds simulating different conditions of loss during extensive grazing

Abstract

Extensive sheep grazing carries both benefits and risks. Whereas the benefits include reduced labor input and optimal (close to natural) welfare conditions for sheep, the risks involve a danger of lambs getting lost on the pasture. The objective of this study was to compare the behavior of lambs and their mothers belonging to two breeds (Polish Merino and Wrzosówka) in three experiment systems simulating the conditions in which lambs tend to get lost on the pasture during extensive grazing: 1) with visual and auditory contact, 2) with auditory contact, and 3) without visual-auditory contact with the flock. Two main questions were analyzed about the first three months of the lambs’ life: 1) the time of finding the flock by the lambs and 2) the behavior patterns of the lambs and ewes, such as the lambs’ movements, the lambs’ and mothers’ vocalization, the reaction to the curtain, the reaction to the observer, and the lambs’ behavior in the field. The study found that the flock finding time in the first and third month of the lambs’ life (experiments 1 and 2, respectively) was shorter in the Wrzosówka breed than in the Merino breed (p ≤ 0.05). Regardless of the scenario, the most frequently observed reactions in the lamb flock were flock calling and navigating to the flock by the shortest route. In the absence of visual and auditory contact, the most frequent response of the Polish Merino and Wrzosówka lambs was to run to the top of the hill and search for the flock. In the third month of life, the lambs of both breeds began to show a higher degree of independence, and the observed patterns of their behavior were similar. The results of the study show that in the first two months of life, the Wrzosówka lambs found the flock faster and were better oriented in the field than the Merino lambs. In the third month of life, the differences in the behavior patterns of the two breeds became very small. This finding could indicate that during extensive grazing, lambs of some breeds, especially those subjected to intensive artificial selection such as the Merino breed, may require more care of the breeder in the first two months of their life.