包膜甜菜碱与有机铬复合物对夏季奶牛产奶性能和血液生化指标的影响

旨在研究包膜甜菜碱和有机铬复合物对夏季奶牛产奶性能和血液生化指标的影响。选择年龄、胎次、泌乳时间和产奶量相近100头泌乳牛,随机分为对照组和试验组,每组50头,对照组饲喂原奶牛场配方日粮,试验组在每天早晨TMR日粮中添加50 g/d包膜甜菜碱和有机铬复合物。结果:与对照组相比,试验组奶牛采食量显著提高(P<0.05),牛奶中体细胞含量显著降低(P<0.05);奶牛乳酸脱氢酶(LDH)含量显著提高(P<0.05);磷酸肌酸激酶(CPK)含量显著降低(P<0.01),谷胱甘肽过氧化物酶(GSH-PX)、超氧化物歧化酶(SOD)含量有上升趋势,丙二醛(MDA)、碱性磷酸酶(ALP)含量有下降趋势,但差异均不显著。试验表明包膜甜菜碱和有机铬具有提高热应激期奶牛采食量、促进代谢和蛋白质合成、缓解奶牛热应激的作用。     

Effect of dietary betaine levels on growth performance and hepatic intermediary metabolism of GIFT strain of Nile tilapia Oreochromis niloticus reared in freshwater

An 8‐week feeding experiment was conducted to determine the effect of dietary betaine levels on the growth performance and hepatic intermediary metabolism of genetically improved farmed tilapia (GIFT) strain of Nile tilapia Oreochromis niloticus (mean initial body weight: 78.3 ± 1.3 g, means ± SD). Six practical diets were formulated with the incorporation of betaine at the levels of 0 (control), 5, 10, 15, 20 and 25 g kg⁻¹. Survival showed no significant differences among the treatments (P > 0.05). The highest and lowest weight gain (WG) and specific growth rate (SGR) were observed for fish fed the diets containing 5 and 0 g kg⁻¹ (control) betaine, respectively. Feed intake showed similar trend with WG and SGR. In contrast, feed conversion ratio was the lowest when dietary betaine level was 5 g kg⁻¹. In general, dietary betaine supplementation showed no significant effect on hepatic composition of tilapia. Condition factor and viscerosomatic index tended to increase with increasing dietary betaine levels from 0 to 5 g kg⁻¹ and then decline when dietary betaine levels further increased from 5 to 25 g kg⁻¹. In contrast, hepatosomatic index declined with increasing dietary betaine levels (P < 0.05). Dietary betaine levels significantly influenced several hepatic enzymatic activities, including succinate dehydrogenase, lactate dehydrogenase, malic dehydrogenase, lipoprotein lipase and hepatic lipase, suggesting that dietary betaine addition had significant effects on nutrient metabolism in the liver. Based on the second‐order polynomial regression analysis of WG, 12.5 g kg⁻¹ of dietary betaine level seemed optimal for genetically improved farmed tilapia strain of O. niloticus.     

转甜菜碱醛脱氢酶基因水稻种子萌发和苗期耐盐性的研究

用0.0、3.0、5.0g/L NaCl对2个转甜菜碱醛脱氢酶(BADH)基因水稻51-22、52-7与受体亲本中花8进行萌发期盐胁迫试验.结果表明,盐胁迫下转基因材料受抑程度小于受体亲本,尤以52-7表现明显.用0.0、3.0、5.0g/L NaCl对51-22、52-7和中花8在幼苗期进行14 d盐胁迫试验.结果表明,低盐胁迫时幼苗受盐害较小,高盐胁迫时转基因材料耐盐性优于受体亲本;在盐胁迫7 d后,转基因材料体内脯氨酸含量明显高于受体亲本,同一品种随盐度增大,脯氨酸含量升高.     

转BADH基因山苜3号(SLM07)紫花苜蓿新品种选育

通过农杆菌介导法将BADH基因成功导人中苜1号紫花苜蓿基因组中,以生长习性、花色、生物量、抗逆性等性状特征为选育目标,选育出了符合既定目标的耐盐苜蓿,定名为山苜3号(SLM07)(Medicago sativa L.cv.Shanmu No.3).通过品比试验、区域试验和生产试验表明,在不同含盐量地区其产草量明显高于中苜1号,生产试验的干草增产率为16.22%～21.52%,为我国耐盐牧草生产提供了新的种质资源.     

甜菜碱含量的测定方法比较

甜菜碱含量的测定方法有很多种,包括酸碱滴定法、紫外分光光度法、高氯酸非水滴定法、离子色谱法等。各种方法均有其优缺点,综合考虑,离子色谱法与非水滴定法的测定结果较好。为比较这两种方法哪种更准确、更方便,设计如下实验。选取5种含量不同的甜菜碱产品,分别用非水滴方法和离子色谱法测定5种产品的甜菜碱含量。实验结果表明,离子色谱法测定的甜菜碱含量与真实值较接近,非水滴定法测定的甜菜碱含量比真实值偏高。     

甜菜碱对1至21日龄肉鸭体脂重分配的作用效果及机理

通过饲养、屠宰试验和有关指标分析,探讨了甜菜碱对21 日龄肉鸭体脂重分配的作用效果及其对脂肪代谢的作用机理。276 只1 日龄樱桃谷肉鸭分成对照组和甜菜碱组两个处理,每个处理138只,每组设3 个重复,每个重复组46 只肉鸭,公母各半。基础饲粮相同(甲硫氨酸和总含硫氨基酸含量分别为0.30% 和0.66% ),对照组饲喂不含甜菜碱的日粮,甜菜碱组饲喂含800 m g/kg 甜菜碱的日粮。肉鸭饲喂到21 日龄时称重、屠宰。结果表明,甜菜碱对21 日龄肉鸭体脂具有显著的重分配作用,它分别降低了鸭的腹脂率、皮脂厚和肝脏粗脂肪含量,提高了鸭胸肌中粗脂肪含量和肌间脂肪的厚度。肝脏、肌肉、腹脂和血清样品分析结果揭示,甜菜碱似通过降低脂肪生成酶的活性(P< 0.01),来提高脂肪分解酶的活力,促进肉碱的合成,加强肝脏、尤其是肌肉组织中长链脂肪酸的β-氧化作用,从而发挥着重新分配肉鸭体脂肪的作用。     

过瘤胃甜菜碱对奶牛泌乳性能和生产性能的影响

实验选取黑龙江省大庆市某集约化奶牛场年龄、胎次、体况及泌乳量相近的健康奶牛40头,随机分为4组,每组10头,Ⅰ、Ⅱ、Ⅲ组日粮中每头每天添加5、10和20 g过瘤胃甜菜碱,Ⅳ组为过瘤胃甜菜碱对照组。试验期从产前14 d至产后42 d,通过对试验奶牛产后乳蛋白（LP）、乳脂率（BF）、乳糖（SL）的分析,研究过瘤胃胆碱和甜...     

3种诱导剂对辣椒幼苗抗寒性的影响

以福湘佳玉辣椒为试验材料,研究低温胁迫下喷施水杨酸、多效唑和甜菜碱对辣椒幼苗植株形态和生化指标的影响.结果表明:适宜浓度的诱导剂处理均能减轻辣椒幼苗的低温伤害程度,提高幼苗壮苗复合指标值;诱导剂处理幼苗叶中的叶绿素、可溶性糖、脯氨酸含量和过氧化物酶活性均高于对照植株,呈先升后降趋势,各诱导剂处理叶绿素、可溶性糖含量的最大值分别比对照高25.93%和61.54%,脯氨酸含量和过氧化物酶活性的最大值分别为对照的1.93倍和2.34倍;相对电导率与丙二醛含量均低于对照植株,呈先降后升趋势,相对电导率与丙二醛含量的最小值分别比对照减少了33.44%和79.31%;3种诱导剂中以水杨酸的抗寒效果较好,多效唑最差,且以7.5 mmol/L水杨酸处理的效果最佳.     

新疆耐盐植物藜的甜菜碱醛脱氢酶基因(CaBADH)的克隆、盐胁迫表达分析及植物表达载体的构建

[目的]为开展植物耐盐基因工程提供候选基因.[方法]研究以新疆耐盐植物藜为材料,利用同源克隆技术从藜中克隆到BADH基因,并通过RT-PCR方法对其在不同盐胁迫下的表达进行了初步分析,随后将该基因构建至高效植物表达载体pCN2300上.[结果](1)经测序分析并与藜科其他植物进行同源性比对显示,得到的序列为藜的BADH基因,开放阅读框长度为1 503 bp,编码500个氨基酸;(2)以BADH基因核心序列设计引物对此基因在盐胁迫下的表达进行了RT-RCR分析,发现其本底表达量较高,以100 mmol/L NaCl处理2、5、12和24 h后其表达量没有明显增加趋势,而以50 mmol/L- NaCl或KCl长期胁迫后其表达量则比对照和100 mmol/L时的表达量高;(3)经双酶切鉴定,已成功将CaBADH基因构建到植物表达载体pCN2300,得到重组质粒pCN2300-CaBADH.[结论]研究为进一步从生理和分子水平阐明藜的耐盐机制提供了一定参考.并为通过转基因技术获得耐盐作物新品种打下基础.     

Effect of graded levels of dietary betaine on ileal and total tract nutrient digestibilities and intestinal bacterial metabolites in piglets*

The study was conducted to investigate the effects of graded dietary inclusion levels of betaine on ileal and total tract nutrient digestibilities and intestinal bacterial metabolites in piglets. A total of eight barrows with an average initial body weight of 7.9 kg were randomly allocated to one of the four assay diets with two pigs per treatment in four repeated measurement periods. The assay diets included a basal diet based on wheat, barley and soybean meal alone, or supplemented with a liquid betaine product at dietary levels of 1.5, 3.0, or 6.0 g betaine per kilogram diet (as‐fed). Ileal digestibilities of dry matter and neutral detergent fibre increased both quadratically and linearly, and ileal digestibility of glycine increased linearly as dietary betaine level increased (p < 0.05). Furthermore, total tract digestibility of crude protein increased quadratically (p < 0.05) and total tract digestibilities of most amino acids tended to increase quadratically (p = 0.06 to p = 0.11) with increasing dietary betaine level. Moreover, there were linear increases in the concentrations of most bacterial metabolites which were significant p < 0.05 for ileal d ‐lactic acid and for faecal diaminopimelic acid. The results demonstrate that dietary betaine supplementation stimulates bacterial fermentation of fibre in the small intestine and bacterial degradation of crude protein in the large intestine.