| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Monsanto Company, St. Louis, MO 63198 and Washington University, St. Louis, MO 63110
Abstract
The purpose of this paper is to review our understanding of the involvement of central and peripheral factors in the control of feed intake in ruminants. The regulation of body weight under various states of energy need depends on an animal's ability to control feed intake to meet these needs. In the central nervous system (CNS), the ventromedial and lateral hypothalamus appear to be the areas involved in satiety and hunger, respectively; other important areas are the paraventricular nucleus and rostral brain areas. Intracerebroventricular injection of neurotransmitters, 
- and ß-adrenergic agonists, 5-hydroxytryptamine and gamma aminobutyric acid (GABA) agonists, has stimulated feeding in ruminants; intravenous administration of benzodiazepines stimulated feed intake in sheep and cattle, possibly by increasing GABA levels in the brain. Neuropeptides of the opioid and cholecystokinin families have reciprocal hunger-stimulating and satiety-eliciting effects when administered centrally in sheep. Further, concentrations of these neuropeptides in specific areas of the hypothalamus have been shown to change with the state of hunger-satiety of sheep. In the periphery, none of the hormones associated with the pituitary, adrenal gland, pancreas or gastrointestinal tract has been shown to have significant effects on the control of feed intake. In addition, the physical properties of the ingested feed in the gastrointestinal tract, while possibly influencing the rate or pattern of feeding, do not appear to be primary factors in the control of feed intake under many feeding conditions. We interpret from this review that much progress has been made in understanding the control of feed intake in ruminants, but continued study on the role of neuropeptides, in particular, is required to provide insight into the mechanism of that control.
1 Presented at Midwestern ASAS Symposium "Factors Influencing Forage Utilization in the Ruminant," March 1985.
2 Nutr. Chem. Div., Monsanto Co., St. Louis, MO 63167.
3 Washington Univ. Med. School, 4566 Scott Ave., St. Louis, MO 63110.
4 The authors are grateful to Drs. M. A. Della-Fera and D. Krestel-Rickert for assistance in the preparation of this manuscript. Research from the author's laboratories were supported in part by grants from NIH (NS 20000) and Monsanto Co.
This article has been cited by other articles:
|
|
 |
|
  A. E. Wertz-Lutz, J. A. Daniel, J. A. Clapper, A. Trenkle, and D. C. Beitz Prolonged, moderate nutrient restriction in beef cattle results in persistently elevated circulating ghrelin concentrations J Anim Sci, March 1, 2008; 86(3): 564 - 575. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Y. Obese, B. K. Whitlock, B. P. Steele, F. C. Buonomo, and J. L. Sartin Long-term feed intake regulation in sheep is mediated by opioid receptors J Anim Sci, January 1, 2007; 85(1): 111 - 117. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
