Preferences of sheep, when supplemented, for forages in a Mediterranean rangeland management system

Abstract

Most rangelands in Jordan are degraded and contain almost no perennial vegetation. A study was conducted near Tal alRumman, Jordan to evaluate grazing behaviour of sheep under typical sheep management conditions where supplemental barley provides the majority of the intake by sheep. The objectives were to determine if sheep preferred herbaceous or woody vegetation and to evaluate a management system that utilises limited areas of ungrazed perennial vegetation in expanses of heavily-grazed and severely-degraded rangeland. Twenty-five Awassi ewes were placed in three 0.1-ha paddocks of ungrazed native rangeland for 2.5 h each day for 3 consecutive days and observed. The three paddocks were grazed for 9 days during each of four seasons: winter, spring, summer and autumn. Sheep were herded to and from the experimental paddocks in the morning and were fed 0.5 kg of barley in the evening. Virtually all grazing occurred in the experimental paddocks because rangeland areas where sheep were housed were severely degraded and contained very little herbage (<40 kg DM ha–1). Herbage mass of herbaceous perennial vegetation in the study area averaged 165 kg DM ha–1 and potentially edible portions (leaves and twigs) of shrubs averaged 82 kg DM ha–1. Sheep spent more time (P < 0.05) grazing than browsing, chewing, standing or ruminating during all seasons. Sheep spent most of their time grazing during the first hour of grazing, and then the time spent grazing declined (P < 0.05) and time standing and ruminating tended to increase near the end of the 2.5-h grazing period. Under typical management in Jordan where sheep are supplemented with barley, sheep clearly preferred herbaceous vegetation over shrubs. To meet sheep preferences, rangeland restoration efforts in Jordan should focus on establishment of mixes of grasses, forbs and shrubs rather than planting only shrubs. This study suggests that allowing sheep access to perennial vegetation for 2–3 h per day can potentially extend the grazing period of limited areas of restored rangeland while providing sheep sufficient time to complete a grazing bout.