Author
 |
Fisher, Dwight |
|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/24/2001 Publication Date: N/A Citation: N/A Interpretive Summary: In the study of the nutrition of animals such as cattle, sheep, and goats many factors have been proposed as controlling feed intake. In some cases, researchers have worked as if a single factor controlled intake independently and exclusively of other factors. A knowledge of the anatomy of cattle, sheep, and goats aids in understanding both the ecological niche and the feeding behavior of these animals. Factors controlling feed intake should be assumed to function as a group with many interactions providing a collective feedback signal for hunger or satiety. A number of feedback regulators such as stomach distension, protein concentration, and energy concentration should be considered together when attempting to predict feeding behavior. Animal behavior also influences feed intake through associations formed between a feed consumed during the course of a meal and the feedback experienced by the animal after a meal. These animals can learn to identify and remember particular feeds and change their feeding behavior based on past positive or negative experiences. Understanding these interactions is the key to improving prediction of intake. Mathematical methods are likely to be important in developing our understanding of feed intake because of the difficulty of studying animal behavior. In spite of these difficulties our knowledge of theoretical feedbacks has already been used to improve feeding systems. Technical Abstract: During the history of ruminant nutrition many factors have been proposed as regulators of voluntary feed intake. In some cases the implicit assumption has been that a factor acted independently and exclusively of other mechanisms. A knowledge of ruminant digestive anatomy aids in understanding both the ecological niche and the feeding behavior of the ruminant animal. Factors controlling ruminant intake should be assumed to function with multiple interactions. A number of feedback regulators such as distension, protein, and energy should be considered in the context of their interacting regulatory effects when attempting to predict intake. Behavioral aspects also influence voluntary feed intake through associations formed via post-ingestive feedback. Ruminants can learn to identify particular feeds and alter intake based on past experiences. An integrated approach is proposed as a means of developing our understanding of ruminant feed intake regulation and eventually to improving prediction of intake. Empirical mathematical methods are likely to be fundamental to developing our understanding of feed intake because of the difficulty of studying the central nervous system. In spite of these difficulties, knowledge of theoretical feedbacks has already been used to develop practical ruminant feeding strategies. |
