胎兒在不良的子宮環(huán)境下發(fā)生程序化作用,，而這種程序化的抑制作用很難隨著出生后營養(yǎng)的恢復(fù)而完全消除。在我國的傳統(tǒng)草原畜牧業(yè)區(qū)域,，季節(jié)性變化對放牧的反芻動物影響較大,。一般來說，冬春季節(jié)是牛羊的繁殖季節(jié),，但由于季節(jié)性變化的影響,，冬春兩季牧草營養(yǎng)價值較差。由于牧草的營養(yǎng)價值低,，因此不能滿足動物營養(yǎng)需求,，最終這種長期營養(yǎng)缺乏的影響可能會對胎兒在子宮內(nèi)的發(fā)育及關(guān)鍵組織器官增殖分化生長發(fā)育模式產(chǎn)生程序化抑制作用。
中科院亞熱帶農(nóng)業(yè)生態(tài)研究所反芻動物營養(yǎng)課題組博士賀志雄在譚支良研究員的指導(dǎo)下,，對瀏陽黑山羊（懷孕母羊）進(jìn)行了妊娠后期營養(yǎng)限制試驗,，研究了蛋白能量限制對羔羊生長及組織發(fā)育的影響。結(jié)果表明,，蛋白能量限制降低了羔羊初生體重,；與對照組相比，蛋白能量限制降低了羔羊初生時胸腺,、心臟,、鄒胃和小腸重量；當(dāng)器官重量與體重相比后,，與對照組相比,，蛋白能量限制顯著降低了胸腺和小腸比例，而肺,、心臟,、腎臟、脾臟、肝臟,、胰腺,、前胃和鄒胃均無限制影響?？傊?，孕期營養(yǎng)限制不止影響了胎兒出生體重，還選擇性地改變了機體組成,。
相關(guān)研究成果發(fā)表在國際期刊Animal Reproduction Science上,。（生物谷 Bioon.com）
生物谷推薦的英文摘要
Anim Reprod Sci doi: 10.1016/j.anireprosci.2013.01.005
He ZX, Wu DQ, Sun ZH, Tan ZL, Qiao JY, Ran T, Tang SX, Zhou CS, Han XF, Wang M, Kang JH, Beauchemin KA.
Protein or energy restriction during late gestation alters fetal growth and visceral organ mass: an evidence of intrauterine programming in goats.
The objective of this study was to examine the effects of maternal protein or energy restriction during late gestation on postnatal fetal growth and visceral organ mass of goats. Eighty pregnant goats with similar age (2.0 ± 0.3 yr) and body weight (BW, 20.0 ± 1.0 kg before pregnancy) were assigned to 3 dietary treatments during late gestation: control (CON), 40% protein restricted (PR) and 40% energy restricted (ER) diets until parturition, after which offspring received normal diets for nutritional recovery. Kids were killed and visceral tissues were harvested at birth and week 6. Maternal protein or energy restriction decreased (P < 0.05) birth weight, and the weights of thymus, heart, abomasums, small intestine. The length of fetus from PR and ER were all decreased (P < 0.05) compared with that from control. When expressed relative to BW, thymus and small intestine for PR and ER still remained less (P < 0.05) than that for control. After 6 weeks of nutritional recovery, there was no difference (P = 0.91) in BW among groups; the kids from nutritional restriction groups showed a greater (P < 0.05) growth rate compared with kids from CON. Moreover, liver (only in ER, P < 0.10) and kidney (only in ER, P < 0.05) were proportionally increased to BW at week 6. The results indicate that maternal protein or energy restriction programs the fetal growth in goats, particularly the proportional responses of fetal organs relative to BW, including thymus, small intestine, kidney and liver.
