فهرس المقالات rumen physiology

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  1 - Physical Form of Calf Starter: Applied Metabolic and Performance Insights
  A. Nikkhah M. Alimirzaei
  The objective of this review article was to evaluate and elaborate on dairy calves’ metabolic and growth responses to different physical forms of dry starter feed in relation to forage in the pre-weaning period. In addition, practical guidelines were discussed for أکثر

  The objective of this review article was to evaluate and elaborate on dairy calves’ metabolic and growth responses to different physical forms of dry starter feed in relation to forage in the pre-weaning period. In addition, practical guidelines were discussed for on-farm uses. Apart from chemical composition, physical structure of solid feeds can influence nutrient intake and growth of young calves. Starter feed intake is essential for the timely development of a functional rumen and successful weaning transition with minimized weaning distresses. The calf starters produced commercially include pelleted, mashed, and texturized forms. Numerous studies have investigated the effects of physical form of starter and feed particle size on dairy calf performance. However, the results have been inconsistent. In addition, forage particle size in dairy calf diets has not been precisely determined and more investigations seem to be required. It is believed that alterations in the physicochemical properties of feed ingredients during processing influences rumen digestion that can partially explain the inconsistencies in research outcomes. Calf starter comprises large amounts of grains with different starch content and varying degradation dynamics, thereby differently affecting the rumen environment and calf growth. Grain type and processing method may interact with other starter ingredients such as forage and high-protein meals, making it difficult to decide which processing method or physical form would be optimal or preferred. Moreover, the first three weeks of calf life is thought to be more critical than the rest of the pre-weaning period, which requires distinct nutritional and management considerations. Encouraging calves to consume solid feed intake in the early ages may be a multi-advantage practice to ensure that calves eat more starter during the rest of the pre-weaning period. Accordingly, physical form of starter diet might affect solid feed intake differently during these two distinct pre-weaning periods. In conclusion, understanding the effects of feed processing on calf rumen physiology and metabolism may provide practical outlooks for optimal preparation of starter diets for calves at different stages of growth. تفاصيل المقالة