共查询到19条相似文献,搜索用时 250 毫秒
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妊娠母猪的氨基酸营养 总被引:1,自引:1,他引:0
母猪的妊娠是一个漫长而复杂的生理过程,妊娠母猪营养供给的合理性直接影响母猪的繁殖性能。由于母猪体内胎儿和自身组织(乳腺等)的不断发育,母体对于饲料中各种营养的需求不断变化,尤其是氨基酸。氨基酸不仅是合成胎儿和母体组织蛋白质的构件物质,同时,特别是在母猪妊娠阶段,一些氨基酸还具有调节特殊生理过程的功能性作用。而且,妊娠母猪的氨基酸需要及理想比率随妊娠期进程而呈动态变化趋势[1]。本文旨在总结氨基酸在提高妊娠母猪繁殖性能、促进胚胎成活与发育方面的研究现状和新发现,探讨妊娠 相似文献
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哺乳动物胎盘营养感应研究进展 总被引:1,自引:1,他引:0
妊娠期间母体营养的改变会影响胎儿的生长发育,而胎盘是母体-胎儿间进行气体、营养和代谢物交流的重要枢纽,哺乳动物胎盘营养感应系统响应母体和胎儿营养信号的变化,保证母体健康和胎儿生长发育。鉴于胎盘营养感应系统对哺乳动物繁育的重要性,本文从胎盘营养感应和胎盘养分分配方面综述了哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)、磷酸腺苷活化蛋白激酶(AMP-activated protein kinase,AMPK)、氨基己糖(Hexosamine)信号通路、糖原合成酶3(glycogen synthase kinase,GSK-3)、胰岛素/胰岛素样生长因子(insulin/insulin-like growth factor signaling pathway,IIS)等信号通路及其对妊娠期养分响应和对胎儿发育的影响,以期为哺乳动物的繁育提供参考依据。 相似文献
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林可 《国外畜牧学(猪与禽)》2010,30(6):39-42
<正>上期回顾:上期介绍了母猪窝产仔数受影响的因素、养猪生产中胎儿宫内发育迟缓问题、胎盘在胚胎发育中的作用主氨基酸在胎盘生长中的作用。5氨基酸对胎儿肌肉和脂肪组织生长发育的影响研究表明,妊娠期间母体的蛋白质营养会影响出生后仔猪的肌肉生长和肌内脂肪的含量(Rehfeldt等,2004)。肌细胞和脂肪细胞来源于普通的造血前体细胞 相似文献
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家畜的妊娠期不尽一致,但每种家畜的妊娠期都有一个大致的范围,如荷斯坦牛为279天、夏洛来牛为287天、瘤牛为296天、绵羊为144~150天。家畜妊娠期受品种、胎儿性别、胎儿数量、胎次及胎儿基因型的影响,环境因素,包括营养、外界温度及季节变化,影响较小,品种对妊娠期长短影响最大。在某些致病因素的作用下可导致牛、羊妊娠期延长,如胎儿死亡和胎儿畸形都可致其妊娠期延长。当牛群或羊群中发生妊娠期延长的病例时,应全面调查,找出原因,进行确切诊断,进而选择可行的治疗措施。 相似文献
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水能载舟,亦能覆舟;药能治病,亦能致命。所以,用药要因病因畜而异。现对孕畜的用药问题,谈谈个人的粗浅看法,供同道参考。(一)胎儿与母体的关系母畜在妊娠期间,胎儿在子宫内生长发育,是通过胎盘与母体进行物质交换的。当胎盘的血液循环发生障碍时,可以引起胎儿缺氧,甚至死亡。胎儿还通过胎盘的渗透作用,从母体摄取营养物质和排泄代谢产物。胎儿在母体内发育,使孕畜既要维持自身的生理活动,又要满足胎儿的营养及代谢需要,这样一来,母 相似文献
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Joel S Caton Matthew S Crouse Kyle J McLean Carl R Dahlen Alison K Ward Robert A Cushman Anna T Grazul-Bilska Bryan W Neville Pawel P Borowicz Lawrence P Reynolds 《Journal of animal science》2020,98(12)
The focus of this review is maternal nutrition during the periconceptual period and offspring developmental outcomes in beef cattle, with an emphasis on the first 50 d of gestation, which represents the embryonic period. Animal agriculture in general, and specifically the beef cattle industry, currently faces immense challenges. The world needs to significantly increase its output of animal food products by 2050 and beyond to meet the food security and agricultural sustainability needs of the rapidly growing human population. Consequently, efficient and sustainable approaches to livestock production are essential. Maternal nutritional status is a major factor that leads to developmental programming of offspring outcomes. Developmental programming refers to the influence of pre-and postnatal factors, such as inappropriate maternal nutrition, that affect growth and development and result in long-term consequences for health and productivity of the offspring. In this review, we discuss recent studies in which we and others have addressed the questions, “Is development programmed periconceptually?” and, if so, “Does it matter practically to the offspring in production settings?” The reviewed studies have demonstrated that the periconceptual period is important not only for pregnancy establishment but also may be a critical period during which fetal, placental, and potentially postnatal development and function are programmed. The evidence for fetal and placental programming during the periconceptual period is strong and implies that research efforts to mitigate the negative and foster the positive benefits of developmental programming need to include robust investigative efforts during the periconceptual period to better understand the implications for life-long health and productivity. 相似文献
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Board-invited review: intrauterine growth retardation: implications for the animal sciences 总被引:1,自引:0,他引:1
Intrauterine growth retardation (IUGR), defined as impaired growth and development of the mammalian embryo/fetus or its organs during pregnancy, is a major concern in domestic animal production. Fetal growth restriction reduces neonatal survival, has a permanent stunting effect on postnatal growth and the efficiency of feed/forage utilization in offspring, negatively affects whole body composition and meat quality, and impairs long-term health and athletic performance. Knowledge of the underlying mechanisms has important implications for the prevention of IUGR and is crucial for enhancing the efficiency of livestock production and animal health. Fetal growth within the uterus is a complex biological event influenced by genetic, epigenetic, and environmental factors, as well as maternal maturity. These factors impact on the size and functional capacity of the placenta, uteroplacental blood flows, transfer of nutrients and oxygen from mother to fetus, conceptus nutrient availability, the endocrine milieu, and metabolic pathways. Alterations in fetal nutrition and endocrine status may result in developmental adaptations that permanently change the structure, physiology, metabolism, and postnatal growth of the offspring. Impaired placental syntheses of nitric oxide (a major vasodilator and angiogenic factor) and polyamines (key regulators of DNA and protein synthesis) may provide a unified explanation for the etiology of IUGR in response to maternal undernutrition and overnutrition. There is growing evidence that maternal nutritional status can alter the epigenetic state (stable alterations of gene expression through DNA methylation and histone modifications) of the fetal genome. This may provide a molecular mechanism for the role of maternal nutrition on fetal programming and genomic imprinting. Innovative interdisciplinary research in the areas of nutrition, reproductive physiology, and vascular biology will play an important role in designing the next generation of nutrient-balanced gestation diets and developing new tools for livestock management that will enhance the efficiency of animal production and improve animal well being. 相似文献
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饲料油菜蛋白质含量高、青饲产量大,可用作多种草食动物的青绿饲料。文章主要就双低饲料油菜的品种特性、利用价值及在动物养殖业中应用等研究状况进行概述,以期为牧草资源开发与草食动物养殖业生产提供科学参考。 相似文献
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动物福利是国内外学者热议的话题,也是标准化生产和畜产品质量安全的重要影响因素.动物福利体现在饲养、养殖环境、健康、行为等各个环节中.马驴作为中国重要的草食家畜,在精准扶贫和乡村振兴中发挥着重要作用.该文阐述了马驴养殖的经济价值,对中国马驴养殖福利现状和动物福利在马驴养殖中的相关影响因素进行探讨,为宣传、提升马驴养殖福利... 相似文献
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Rehfeldt C Nissen PM Kuhn G Vestergaard M Ender K Oksbjerg N 《Domestic animal endocrinology》2004,27(3):267-285
Prenatal growth is very complex and a highly integrated process. Both maternal nutrition and the maternal somatotropic axis play a significant role in coordinating nutrient partitioning and utilization between maternal, placental and fetal tissues. Maternal nutrition may alter the nutrient concentrations and in turn the expression of growth regulating factors such as IGFs and IGFBPs in the blood and tissues, while GH acts in parallel via changing IGFs/IGFBPs and nutrient availability. The similarity in the target components implies that maternal nutrition and the somatotropic axis are closely related to each other and may induce similar effects on placental and fetal growth. Severe restriction of nutrients throughout gestation has a permanent negative effect on fetal and postnatal growth, whereas the effects of both temporary restriction and feeding above requirements during gestation seem to be of transitional character. Advantages in fetal growth gained by maternal growth hormone treatment during early to mid-gestation are not maintained to term, whereas treatment during late or greatest part of gestation increases progeny size at birth, which could be of advantage for postnatal growth. This review summarizes the available knowledge on the effects of different maternal feeding strategies and maternal GH administration during pregnancy and their interactions on metabolic and hormonal (especially IGFs/IGFBPs) status in the feto-maternal unit, skeletal muscle development and growth of the offspring in pigs. 相似文献
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The aims of this study were to ascertain 1) whether fetal maturation could be induced precociously by maternal administration with adrenocorticotrophic hormone (ACTH) and 2) whether maturation could be achieved without significant risk to mare or fetus. Twenty-two mares received either 1 mg (low dose, LD, n = 6) or 4 or 5 mg (higher dose, HD, n = 16) synthetic Depot ACTH(1-24) at 300, 301 and 302 days gestation. Because, during the course of the study, ACTH appeared to have a greater influence on mares mated during the later part of the breeding season, the HD group were divided retrospectively into those mated before (HDE, n = 6), or after (HDL, n = 10), 1st July. All LD mares were mated before 1st July. Control injections were not performed but gestational data were compared retrospectively with 64 untreated, spontaneously foaling pony mares mated between May and October. Plasma progestagen and cortisol concentrations increased significantly (P<0.05) following ACTH administration in all groups, but progestagens were higher and cortisol elevated for longer in HD mares. ACTH stimulated mammary development and milk electrolyte changes in HD mares. Mean +/- s.e. gestation period (days) was significantly (P<0.01) shorter in HDL mares (318 +/- 1.8) compared with LD (335 +/- 3.7), HDE (340 +/- 4.3) and untreated mares mated after 1st July (327 +/- 1.3). All foals were mature except 2 HDL foals which were stillborn. HDL foals had a higher MCV and lower mean bodyweight, indicating they were delivered before full term. In conclusion, maternal ACTH administration appears to accelerate fetal maturation and delivery in pony mares given high doses and mated late in the breeding season. Further work is required to establish the optimal gestational age and dosage for maternal ACTH administration before clinical recommendations can be given for this therapy. 相似文献