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Full-Text Articles in Animal Sciences
Beef, Dairy, Equine, Poultry, Hogs, Sheep, And Goats, Kenneth H. Burdine, A. Lee Meyer
Beef, Dairy, Equine, Poultry, Hogs, Sheep, And Goats, Kenneth H. Burdine, A. Lee Meyer
Agricultural Economics Presentations
No abstract provided.
Selected Hormonal And Neurotransmitter Mechanisms Regulating, James L. Sartin, Joseph A. Daniel, Brian K. Whitlock, Robyn R. Wilborn
Selected Hormonal And Neurotransmitter Mechanisms Regulating, James L. Sartin, Joseph A. Daniel, Brian K. Whitlock, Robyn R. Wilborn
Faculty Publications and Other Works -- Large Animal Clinical Sciences
Appetite control is a major issue in normal growth and in suboptimal growth performance settings. A number of hormones, in particular leptin, activate or inhibit orexigenic or anorexigenic neurotransmitters within the arcuate nucleus of the hypothalamus, where feed intake regulation is integrated. Examples of appetite regulatory neurotransmitters are the stimulatory neurotransmitters neuropeptide Y (NPY), agouti-related protein (AgRP), orexin and melanin-concentrating hormone and the inhibitory neurotransmitter, melanocyte-stimulating hormone (MSH). Examination of messenger RNA (using in situ hybridization and realtime PCR) and proteins (using immunohistochemistry) for these neurotransmitters in ruminants has indicated that physiological regulation occurs in response to fasting for several …
Changes In Plasma Concentrations Of Growth Hormone And Luteinizing Hormone In Ewes Following Central And Peripheral Treatment With Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Barbara P. Steele, James L. Sartin
Changes In Plasma Concentrations Of Growth Hormone And Luteinizing Hormone In Ewes Following Central And Peripheral Treatment With Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Barbara P. Steele, James L. Sartin
Animal Science Publications and Other Works
Kisspeptin (KP), a neuroendocrine regulator of gonadotropin releasing hormone, has been hypothesized as an integrator of nutrition and hormones critical to metabolism and regulation of reproduction. Recent evidence suggests growth hormone (GH) secretion may be influenced by KP. The objective of this study was to determine if the GH stimulatory effect of KP is due to actions on the hypothalamus or anterior pituitary gland in ewes. Adult ovariectomized ewes (n=8) were fitted with intracerebroventricular (ICV) cannula to facilitate central administration of experimental treatments. Ewes received one of eight treatments [four intravenously (IV) and four ICV]. Peripheral treatments [0 (Veh), 100, …
Changes In Plasma Concentrations Of Leptin In Ewes During Pregnancy, Joseph A. Daniel, A B. Milam, M E. Gafnea, Brian K. Whitlock, D H. Keisler
Changes In Plasma Concentrations Of Leptin In Ewes During Pregnancy, Joseph A. Daniel, A B. Milam, M E. Gafnea, Brian K. Whitlock, D H. Keisler
Animal Science Publications and Other Works
Previous research has demonstrated circulating concentrations of leptin increase in ewes during mid pregnancy then decline in late pregnancy and early lactation. The objective of this study was to more narrowly define the timing of changes in circulating concentrations of leptin with pregnancy in ewes. Katahdin ewes (n= 19) located at latitude 34.275 and longitude -85.183 (Mount Berry, GA) were utilized. Blood samples were collected weekly via jugular veinpuncture beginning immediately before ram exposure on September 23 and continuing until 4 weeks post-lambing. Ewes were exposed to a ram fitted with a marking harness for a 63 day breeding season. …
Validation Of Live Animal Ultrasonic Measurements Of Body Composition In Market Lambs, J. C. Emenheiser, S. P. Greiner, Ronald M. Lewis, D. R. Notter
Validation Of Live Animal Ultrasonic Measurements Of Body Composition In Market Lambs, J. C. Emenheiser, S. P. Greiner, Ronald M. Lewis, D. R. Notter
Department of Animal Science: Faculty Publications
Market lambs from the state fair of Virginia (n = 172) were ultrasonically evaluated by 4 scan technicians and 3 image interpreters to determine accuracy of ultrasonic estimates of loin muscle area (ULMA), backfat thickness (UBF), and body wall thickness (UBW). Lambs were initially scanned at the preferred magnification setting of each technician; 2 chose 1.5× and 2 chose 2.0×. Lambs were then scanned a second time for ULMA and UBF with machine magnification settings changed from 1.5 to 2.0×, or vice versa, midway through the second scan. Lambs were then slaughtered, and analogous measurements [carcass loin muscle area, …
Feed Intake Of Sheep As Affected By Body Weight, Breed, Sex, And Feed Composition, R. M. Lewis, G. C. Emmans
Feed Intake Of Sheep As Affected By Body Weight, Breed, Sex, And Feed Composition, R. M. Lewis, G. C. Emmans
Department of Animal Science: Faculty Publications
The hypotheses tested were that genetic size-scaling for mature BW (A, kg) would reduce variation in intake between kinds of sheep and that quadratic polynomials on u = BW/A with zero intercept would provide good descriptions of the relationship between scaled intake (SI, g/A0.73 d) and degree of maturity in BW (u) across feeds of differing quality. Both sexes of Suffolk sheep from 2 experimental lines (n = 225) and from 3 breed types (Suffolk, Scottish Blackface, and their cross; n = 149) were recorded weekly for ad libitum feed intake and BW; recording of intake was from weaning through, …