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Supplementing diets of Awassi ewes with olive cake and tomato pomace: on-farm recovery of effects on yield, composition and fatty acid profile of the milk


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.

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Our thanks go especially to the farmers Abu Bakri, Abu Khaled, Dhirar Al Nassani, Fawaz, Mohamed Al Nassani and Said for participating in the present study with intensive and thorough work and being generous during the entire experiment. We thank Dr. Safouh Rihawi for his assistance in diet formulation, Monika Zaklouta for her assistance in coordinating the experiments, Ahmad Sawass for coordinating the milk sampling and Ali Al Jassim for supervising the feed mixing and distribution to the farms. We are grateful to all technicians and workers at ICARDA for their great help in the animal experiments and laboratory analyses.

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Correspondence to Michael Kreuzer.

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Abbeddou, S., Rischkowsky, B., Hilali, M.E. et al. Supplementing diets of Awassi ewes with olive cake and tomato pomace: on-farm recovery of effects on yield, composition and fatty acid profile of the milk. Trop Anim Health Prod 47, 145–152 (2015).

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  • Sheep
  • Milk
  • Fatty acid
  • Olive cake
  • Tomato pomace
  • Syria