Abstract:
Genetic selection for high growth rate has resulted in spectacular progress in feed efficiency in chickens. As feed intake and water consumption (WC) are associated and both are affected by environmental conditions, we evaluated WC and its hypothalamic regulation in three broiler-based research lines and their ancestor jungle fowl (JF) under heat stress (HS) conditions. Slow growing ACRB, moderate growing 95RB, fast growing MRB, and JF were exposed to daily chronic cyclic HS (36 °C, 9 h/d) or thermoneutral temperature (24 °C). HS increased WC in the MRB only. Arginine vasopressin (AVP) mRNA levels were decreased by HS in the MRB. Within the renin-angiotensin-aldosterone system (RAAS) system, renin expression was increased by HS in the JF, ACRB, and 95RB, while angiotensin I-converting enzyme (ACE), angiotensin II receptors (type 1, AT1, and type 2, AT2) were affected by line. The expression of aquaporin (AQP2, 7, 9, 10, 11, and 12) genes was upregulated by HS, whereas AQP4 and AQP5 expressions were influenced by line. miRNA processing components (Dicer1, Ago2, Drosha) were significantly different among the lines, but were unaffected by HS. In summary, this is the first report showing the effect of HS on hypothalamic water channel- and noncoding RNA biogenesis-related genes in modern chicken populations and their ancestor JF. These results provide a novel framework for future research to identify new molecular mechanisms and signatures involved in water homeostasis and adaptation to HS.
摘要:
高生长速率的遗传选择导致了鸡饲料效率的惊人进步。由于饲料摄入量和水消耗(WC)是相关的,两者都受到环境条件的影响,我们在热应激(HS)条件下评估了三个基于肉鸡的研究系及其祖先丛林家禽(JF)的WC及其下丘脑调节。缓慢增长的ACRB,中等生长95RB,快速增长的MRB,和JF每天暴露于慢性循环HS(36°C,9h/d)或热中性温度(24°C)。HS仅在MRB中增加WC。MRB中的HS降低了精氨酸加压素(AVP)mRNA水平。在肾素-血管紧张素-醛固酮系统(RAAS)系统内,在JF中,HS增加了肾素表达,ACRB,和95RB,而血管紧张素I转换酶(ACE),血管紧张素II受体(1型,AT1和2型,AT2)受到线的影响。水通道蛋白(AQP2,7,9,10,11和12)基因的表达被HS上调,而AQP4和AQP5的表达受品系的影响。miRNA加工成分(Dicer1,Ago2,Drosha)在品系之间存在显着差异,但不受HS的影响。总之,这是首次报告显示HS对现代鸡种群及其祖先JF中下丘脑水通道和非编码RNA生物发生相关基因的影响。这些结果为未来研究提供了新的框架,以确定水稳态和适应HS的新分子机制和特征。