Cline M.A.,Radford University |
Layne J.E.,Radford University |
Calchary W.A.,Radford University |
Sheehy R.R.,Radford University |
And 2 more authors.
General and Comparative Endocrinology | Year: 2010
Although LPLRFamide was the first member of the RFamide family to be isolated from a vertebrate species, its effects on hunger and satiety-related processes are poorly documented. Thus, we intracerebroventricularly administered LPLRFamide (3.0-15.0 nmol) to both Cobb-500 (a broiler type of Gallus gallus) and Bobwhite quail (Colinus virginianus) chicks and measured their food intake. The threshold of anorexigenic response was 7.0 nmol in Cobb-500 chicks and the effect had diminished by 30 min post-injection. In Bobwhite quail all doses of LPLRFamide tested caused anorexia that remained throughout the 60 min observation period. A comprehensive behavior analysis was conducted and Cobb-500 chicks had increased food pecks early in the observation period and spent a greater amount of time in deep rest. Although food pecks were increased pecking efficiency was decreased. In Bobwhite quail, feeding pecks and the number of jumps were reduced after LPLRFamide treatment. We judged that these behaviors in both species were likely not competitive with ingestion and thus did not secondarily contribute to anorexia. These results demonstrate that LPLRFamide is associated with satiety-related processes in Cobb-500 chicks and Bobwhite quail, while threshold of responses are different. © 2009 Elsevier Inc. All rights reserved.
Tachibana T.,Laboratory of Animal Production |
Khan Md.S.I.,Laboratory of Animal Production |
Matsuda K.,Laboratory of Animal Production |
Ueda H.,Laboratory of Animal Production |
Cline M.A.,Radford University
Hormones and Behavior | Year: 2010
The purpose of the present study was to determine whether central administration of substance P (SP), a tachykinin neuropeptide, influenced feeding behavior in layer chicks (Gallus gallus). Intracerebroventricular (ICV) injections of 5 nmol SP decreased food intake in 5- and 6-day-old chicks under both ad libitum and 3-h fasting conditions. There are 3 major subtypes of tachykinin receptors, namely, neurokinin 1, 2 and 3 receptors. Injection of neurokinin A and neurokinin B, which are respectively endogenous agonists for neurokinin 2 and 3 receptors, did not suppress feeding behavior in chicks, suggesting that the anorexigenic effect of SP might be mediated by the neurokinin 1 receptor rather than neurokinin 2 and 3 receptors. Chicks that received 5 nmol SP did not change their locomotion, standing, sitting or drinking time, suggesting that its anorexigenic action might not be due to SP-induced hyperactivity or sedation. ICV injection of SP increased water intake, also indicating that SP likely did not affect feeding behavior through malaise. In addition, the anorexigenic effect of SP might not be related to corticotrophin-releasing hormone (CRH) because plasma corticosterone concentration was not affected by ICV injection of SP and co-administration of the CRH receptor antagonist astressin did not affect the anorexigenic effect of SP. The present study suggests that central SP acts as an anorexigenic neuropeptide in chicks. © 2009 Elsevier Inc. All rights reserved.
Rjiba Ktita S.,National Institute of Agricultural Research of Tunisia INRAT |
Chermiti A.,National Institute of Agricultural Research of Tunisia INRAT |
Mahouachi M.,Laboratory of Animal Production
Small Ruminant Research | Year: 2010
The objective of this experiment was to evaluate the nutritive value of two seaweeds (Ruppia maritima and Chaetomorpha linum) and the possibility of including them in a concentrate for partial replacement of common ingredients. Each species was incorporated in a concentrate at 20% level with barley and soybean meal. These two concentrates were compared to a control composed of 80% barley, 17.5% soybean meal and 2.5% mineral and vitamin supplement (MVS). The same proportion of MVS was incorporated in the two other concentrates. Twenty-one 5-month-old weaned Barbarine lambs (21.1 ± 2.7 kg body weight) were divided into three groups and housed in individual boxes then in metabolism cages. Each lambs group received one of the above concentrate ad libitum and 300 g/day of oat hay. The three concentrates had similar crude protein (CP) contents (18% DM) but different proportions of ash. Seaweed-containing concentrates are higher in ash than control concentrate (12% DM vs. 5% DM). Dry matter (DM), organic matter (OM) and CP digestibility were similar (P > 0.05) for the control group (77%, 79% and 77%, respectively) and the seaweed groups (74%, 76% and 72% DM, respectively). Nitrogen retention was not affected by diet composition (12 g/day), it representing 47% of N intake. Average daily gain (ADG) was not affected by diet composition (P > 0.05) and lambs grew at rates 183, 172 and 138 g with control, Ruppia and Chaetomorpha diets, respectively. Feed conversion ratio was similar for control and Ruppia diets (6.1) and slightly higher for animals fed diet including Chaetomorpha (7.3). It is concluded that seaweeds evaluated in this study (i.e. Ruppia maritima and Chaetomorpha linum) could be used as alternative feed resources for growing lambs during drought periods. © 2010.