Examination of difference in central nervous system between chickens selected for meat and egg production

这个项目的目的是澄清与体内平衡、摄食行为、应激反应和渗透调节有关的中枢神经系统在选择肉鸡和蛋鸡之间的差异。蛋型鸡胚胎期和孵后早期下丘脑神经肽Y （NPY）含量高于肉型鸡，这与外源性NPY不一致。与蛋型鸡相比，中型鸡下丘脑中高丰度的促黑素原皮质素mRNA和脑室内注射β - msh更大的厌氧性作用可能是它们能够吃更多饲料的原因。除此之外，下丘脑中血清素和多巴胺的周转率也可能与两种鸡的不同摄食行为有关。分离后鸡的运动活动和发声次数减少与褪黑素分泌减少有关，肉型鸡的松果体、叶、脑干的褪黑素分泌增多。肉型鸡胚期产热量较蛋型鸡少，脂质代谢较蛋型鸡活跃，这可能是肉型鸡生长较快的因素之一。名古屋鸡被选择为肉和蛋类型是有用的动物，表明胚胎产热和对应激源的反应是选择的项目。高渗生理盐水注射后下丘脑精氨酸缩宫素基因的表达不仅可能通过下丘脑的TonEBP，也可能通过TonEBP以外的其他途径介导。两种鸡下丘脑对丙氨酸和NPY免疫反应的细胞和纤维分布相似。两种鸡下丘脑的NPY神经元被认为投射到室旁核的旁细胞神经元。总的来说，两种类型的鸡在含有调节肽的神经元结构上几乎没有差异，但肽基因的表达和神经递质代谢的一些差异已被证明有助于鸡的表型。少

The aim of this project is to clarify the difference in the central nervous system related to homeostasis, feeding behavior, responses to stress and osmotic regulation, between chickens selected for meat and egg production.Neuropeptide Y (NPY) peptide content in the hypothalamus during embryonic and early post-hatched period was larger in the egg-type than in the meat-type chickens, which is inconsistent with orexigenic exogenous NPY. Compared to egg-type chickens, higher abundance proopiomelanocortin mRNA in the hypothalamus and larger anorexigenic effect of intracerebroventricularly injected beta-MSH in the meta-type chickens are likely to be responsible for their ability to eat more feed. In addition to this, the turnover rate of serotonin and dopamine in the hypothalamus might be also associated with the different feeding behavior between both types of chickens.Less locomotion activity and vocalization number induced by isolation of chickens was involved in the lower melatonin prod … More uction in the pineal, lobe, brain stem in the meat-type chickens. Heat production during embryonic period was less and lipid metabolism in the meat-type chickens was more active than those in the egg-type chickens, which may be one of factors to make the former grow faster. Nagoya chickens being selected for meat- and egg-types were useful animals to show that the embryonic heat production and responses to stressor are items for selection.Arginine vasotocin gene expression in the hypothalamus responding to hypertonic saline injection was likely to be mediated through hypothalamic not only TonEBP but any other pathway than TonEBP.Distribution of cells and fibers immunoreactive to galanin and NPY in the hypothalamus was similar between both the types of chickens. NPY neuron in the hypothalamus was suggested to project to the parvocellular neuron of the paraventriclular nucleus in both types of chickens.Collectively, there is little differences in the structure of the neuron containing regulatory peptide between the two types of chickens, but some differences in the expression of peptide genes and in neurotransmitters metabolism have been shown to contribute to the phenotype of chickens. Less