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Awassi dairy sheep farmers in the Middle East are facing high feed costs, particularly during the milk production season, along with large fluctuation in grain and straw prices. Incorporating agro-industrial byproducts into the diet of Awassi dairy sheep can help to balance diets and decrease costs. But it may affect milk quality through changes in the fatty acid profile. Six experimental diets were compared to a control diet in the research station of the International Center for Agricultural Research in the Dry Areas (ICARDA) in Tal Hadya, Syria. Milking Awassi ewes (n = 56) were used to test six experimental diets, in which supplements comprised molasses, sugar beet pulp, or cotton seed cake to a traditional control diet contained barley, wheat bran, and barley straw. Milk samples were collected on a weekly basis from April to June. The daily milk production and fat content were enhanced in diets containing urea-treated wheat straw (P

Journal of Dairy Research, 78 (4), ISSN:0022-0299, ISSN:1469-7629

This study investigated whether offering either binary or multiple choice among low quality forages has an effect on intake and feeding behaviour compared to no-choice situations where only one single low-quality forage is offered. Forages from different woody plants and straw were tested in lactating sheep either in Syria (Exp. 1; Awassi sheep) or in Switzerland (Exp. 2; East Friesian Dairy sheep). Artemisia herba-alba, Atriplex leucoclada, Haloxylon articulatum, Noaea mucronata, and Salsola vermiculata were used in Exp. 1. The three most preferred plants (A. leucoclada, H. articulatum and S. vermiculata) were tested again in Exp. 2 together with Betula pendula, Castanea sativa and Juglans regia. Both experiments started with a binary choice test where one plant and barley straw were offered separately for 4 h in the morning to six sheep (test period) in a random sequence in consecutive 7-day sub-periods. A control group (n = 6 per experiment) received only straw in the test period. For the rest of the day, a basal diet composed of straw ad libitum and concentrate was offered. After the binary choice test, two 2-week periods followed, where in the first straw only and in the second all test plants were offered to all animals from both groups to ascertain equal familiarisation with all plants. For the following 7-day multiple choice test animals were allocated to two new groups. The ‘multiple choice’ group could choose among all test plants and straw during the 4-h test period, the ‘control’ group received only the basal diet. Intakes of test feeds during 4 h and 24 h as well as feeding behaviour during the first 30 min were recorded. Additionally, nutrient intake was determined. Total daily test feed intake was always higher in the choice groups, but this was more pronounced in the multiple choice situation (Exp. 1: 30 and 48, Exp. 2: 49 and 74 g dry matter/kg live-weight0.75 with ‘control’ and ‘multiple choice’, respectively). A. leucoclada (Exp. 1; proportionately 0.73 of total test plant intake) and B. pendula (Exp. 2; 0.87) were the preferred plants in the multiple choice test and also with binary choice. Most other feeds were only consumed in low amounts in the binary and even less in multiple choice situations. In conclusion, giving sheep the choice among low quality forages seemed to be advantageous. Even though in both experiments animals preferred especially one plant, choice still facilitated intake.

Two experiments were carried out in Syria with the purpose of investigating to which extent the effects of including 30 % olive cake (replacing parts of forage and concentrate) or tomato pomace (replacing concentrate) in the diet, described under controlled on-station conditions, can be recovered on farm. A total of 180 lactating Awassi ewes (three farms per experiment, 15 ewes per treatment) were fed either control diets or test feed diets over a period of 7 weeks. Milk yield was measured bi-weekly and milk composition was analysed for gross physicochemical composition and fatty acid (FA) profile. Both feeds reduced milk yield (−10 %) and milk protein content, whereas milk fat content was increased by tomato pomace. Both feeds resulted in similar changes in milk FA profile, namely less saturated and polyunsaturated FA and more monounsaturated FA including 18:1 trans FA. Tomato pomace and olive cake also resulted in increased n-6:n-3 FA ratios, while the proportion of the conjugated linoleic acids was not affected by either treatment. In conclusion, the response of the ewes on farm was clear and similar in nature for most of milk-related traits as that found on station, but lower in magnitude., Tropical Animal Health and Production, 47 (1), ISSN:0049-4747, ISSN:1573-7438