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Neonatal Chicks (neonatal + chick)
Selected AbstractsBehavioral regulators in the brain of neonatal chicksANIMAL SCIENCE JOURNAL, Issue 3 2007Mitsuhiro FURUSE ABSTRACT Domestic chickens are precocial and therefore have relatively well-developed processes at hatch. As a result, neonatal chicks grow well at hatch with no parental care. The regulation of food intake in animals, including domestic birds, is complicated. Just after hatching, neonatal chicks find their food by themselves and they can control their food intake. Recently, prolactin releasing peptide and gonadotropin-inhibitory hormone were confirmed as central orexigenic factors in the neonatal chick. Both peptides have a common structure as RFamide peptides. On the other hand, vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide, both belonging to the glucagon superfamily, were recognized as inhibitory. Broiler chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamus-pituitary-adrenal axis compared with layer chicks. These differences are explained by higher melatonin concentrations in the pineal gland and other parts of the brain of broiler chicks since melatonin attenuates the stress response. Stressful behavior in chicks can be attenuated by neurotransmitters or by nutrients such as creatine, phosphatidylserine, L-serine and (-)-epigallocatechin gallate. It is suggested that the regulation of behavior is somewhat specific and can be attenuated by some manipulation in neonatal chicks. [source] Central regulation of food intake in the neonatal chickANIMAL SCIENCE JOURNAL, Issue 2 2002Mitsuhiro FURUSE ABSTRACT Regulating food intake is complicated in animals including domestic birds. Just after hatching, neonatal chicks find their food by themselves and they can control food intake, since domestic chicken belongs to the precocial type of avian species. Thus, domestic chickens have relatively well-developed mechanisms of food-intake control at hatching. While many aspects of food-intake regulation in chickens appear similar to that in mammals, there are some responses that are unique to chickens. For instance, some neurotransmitters such as neuropeptide Y (NPY), orexin-A, orexin-B, motilin, melanin-concentrating hormone (MCH), galanin, growth hormone releasing factor (GRF) and ghrelin stimulate feeding in mammals. Only NPY strongly stimulates food intake in birds similar to that observed in mammals; however, both orexins, motilin, MCH and galanin failed to alter food intake of the chick. Moreover, GRF and ghrelin suppressed feeding of chicks. On the other hand, cholecystokinin (CCK), gastrin, glucagon-like peptide-1 (GLP-1), corticotropin-releasing factor (CRF), histamine, ,-melanocyte stimulating hormone (,-MSH), leptin and bombesin are known to suppress feeding in mammals. These responses are similar to those of mammals except for leptin. Therefore, the inhibitory mechanisms for feeding are well conserved in chicks. [source] Intracerebroventricular administration of GABA-A and GABA-B receptor antagonists attenuate feeding and sleeping-like behavior induced by L -pipecolic acid in neonatal chicksJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2003T. Takagi Abstract It has been demonstrated that L -pipecolic acid (L -PA), a major metabolic intermediate of L -lysine (L -Lys) in the mammalian and chicken brain, is involved in the functioning of the GABAergic system. A previous study has shown that intracerebroventricular (i.c.v.) injection of L -PA suppressed feeding and induced sleep-like behavior in neonatal chicks; however, the precise relationship between the GABAergic system and L -PA has not been clarified. In the present study, the role of the GABA-A or GABA-B receptors in the suppression of food intake and induction of sleeping-like behavior by L -PA was investigated. Chicks were injected i.c.v. with the GABA-A antagonist picrotoxin or GABA-B antagonist CGP54626 along with L -PA. Although suppression of food intake by L -PA was restored partially by co-injection with CGP54626, but not picrotoxin, sleep-like behavior induced by L -PA was suppressed significantly by both antagonists. These results suggested that L -PA activated both GABA-A and GABA-B receptors, and GABA-B receptors alone contributed to food intake whereas both receptors contributed to sleep-like behavior. © 2003 Wiley-Liss, Inc. [source] Central L-cysteine induces sleep, and D-cysteine induces sleep and abnormal behavior during acute stress in neonatal chicksANIMAL SCIENCE JOURNAL, Issue 4 2009Haruka YAMANE ABSTRACT L-Cysteine (L-Cys) is a non-essential and glycogenic amino acid. Previously, we reported that the intracerebroventricular (i.c.v.) injection of L-Cys induced sedative effects under isolation-induced stress in neonatal chicks. L-Cys has an optical isomer, D-Cys. The aim of this study was to clarify the effect of L-Cys and D-Cys during a stressful condition in chicks. The i.c.v. injection of L-Cys and D-Cys (0.84 µmol) decreased both distress vocalization and spontaneous activity induced by isolation. However, the two cysteine isomers induced different behaviors. L-Cys increased sleep-like behavior while D-Cys caused abnormal behavior including syncope as well as sleep-like behavior. In conclusion, while both L-Cys and D-Cys caused a sedative effect when injected i.c.v, D-Cys caused abnormal behavior and may be detrimental to neonatal chicks. [source] Intracerebroventricular injection of L-aspartic acid and L-asparagine induces sedative effects under an acute stressful condition in neonatal chicksANIMAL SCIENCE JOURNAL, Issue 3 2009Haruka YAMANE ABSTRACT The present study was conducted to clarify the central functions of L-aspartic acid (Asp) and L-asparagine (Asn) during an acute stressful condition in chicks. Intracerebroventricular (i.c.v.) injection of Asp and Asn (0.84 µmol) attenuated the vocalization that normally occurs during social separation stress. Asp decreased the time spent in active wakefulness and induced sedation. Asn had a similar effect to Asp, although somewhat weaker. However, i.c.v. injection of Asp and Asn further enhanced plasma corticosterone release under social separation stress. Taken together, the i.c.v. injection of Asp and Asn has sedative effects under an acute stressful condition, which does not involve the hypothalamic-pituitary-adrenal axis. [source] Reduced glutathione decreases energy expenditure in chicks exposed to separation stressANIMAL SCIENCE JOURNAL, Issue 3 2009Haruka YAMANE ABSTRACT Recently, we reported that intracerebroventricular (i.c.v.) injection of reduced glutathione (GSH) induces hypnotic and sedative effects under an acute stressful condition in chicks. However, no information is available on the effects of GSH on energy expenditure (EE) under stressful conditions. The purpose of the present study was to clarify whether i.c.v. injection of GSH affects EE of neonatal chicks, and whether EE is correlated with behavioral changes after isolation-induced stress. The EE was rapidly decreased by i.c.v. injection of GSH, but was increased 27 min after injection. This change in EE was correlated with behavioral changes in which GSH induced hypnotic and sedative effects shortly after injection, followed by a period in which activity increased. The present study demonstrates that central GSH initially causes lowered EE through hypnotic and sedative effects under an acute stressful condition in chicks. [source] Stress responses in neonatal meat and layer Nagoya chicksANIMAL SCIENCE JOURNAL, Issue 5 2007Shozo TOMONAGA ABSTRACT We reported that meat chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamic-pituitary-adrenal response to novel environments compared with layer chicks in a commercial base. The present study compared the differences in behavior and plasma corticosterone concentrations under isolation-induced stress between neonatal meat and layer Nagoya chicks which had been separated from the same population. Both types of neonatal chicks reared in groups were individually separated and their spontaneous activity and distress-induced vocalizations were monitored for 10 min. The responses of the two types were remarkably different, with the meat chicks being less active than the layer chicks. Distress-induced vocalizations were fewer in the meat than in the layer chicks. The meat chicks spent more time in a sleeping posture during isolation-induced stress. Plasma corticosterone concentrations measured at the end of the test tended to be higher in the layer chicks than in meat ones, but not significantly. In conclusion, the selection of Nagoya chickens for meat and layer may have trends similar to those observed in commercial chickens in relation to stress susceptibility. [source] Behavioral regulators in the brain of neonatal chicksANIMAL SCIENCE JOURNAL, Issue 3 2007Mitsuhiro FURUSE ABSTRACT Domestic chickens are precocial and therefore have relatively well-developed processes at hatch. As a result, neonatal chicks grow well at hatch with no parental care. The regulation of food intake in animals, including domestic birds, is complicated. Just after hatching, neonatal chicks find their food by themselves and they can control their food intake. Recently, prolactin releasing peptide and gonadotropin-inhibitory hormone were confirmed as central orexigenic factors in the neonatal chick. Both peptides have a common structure as RFamide peptides. On the other hand, vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide, both belonging to the glucagon superfamily, were recognized as inhibitory. Broiler chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamus-pituitary-adrenal axis compared with layer chicks. These differences are explained by higher melatonin concentrations in the pineal gland and other parts of the brain of broiler chicks since melatonin attenuates the stress response. Stressful behavior in chicks can be attenuated by neurotransmitters or by nutrients such as creatine, phosphatidylserine, L-serine and (-)-epigallocatechin gallate. It is suggested that the regulation of behavior is somewhat specific and can be attenuated by some manipulation in neonatal chicks. [source] Central regulation of food intake in the neonatal chickANIMAL SCIENCE JOURNAL, Issue 2 2002Mitsuhiro FURUSE ABSTRACT Regulating food intake is complicated in animals including domestic birds. Just after hatching, neonatal chicks find their food by themselves and they can control food intake, since domestic chicken belongs to the precocial type of avian species. Thus, domestic chickens have relatively well-developed mechanisms of food-intake control at hatching. While many aspects of food-intake regulation in chickens appear similar to that in mammals, there are some responses that are unique to chickens. For instance, some neurotransmitters such as neuropeptide Y (NPY), orexin-A, orexin-B, motilin, melanin-concentrating hormone (MCH), galanin, growth hormone releasing factor (GRF) and ghrelin stimulate feeding in mammals. Only NPY strongly stimulates food intake in birds similar to that observed in mammals; however, both orexins, motilin, MCH and galanin failed to alter food intake of the chick. Moreover, GRF and ghrelin suppressed feeding of chicks. On the other hand, cholecystokinin (CCK), gastrin, glucagon-like peptide-1 (GLP-1), corticotropin-releasing factor (CRF), histamine, ,-melanocyte stimulating hormone (,-MSH), leptin and bombesin are known to suppress feeding in mammals. These responses are similar to those of mammals except for leptin. Therefore, the inhibitory mechanisms for feeding are well conserved in chicks. [source] | ||||||||||