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1.
The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.  相似文献   
2.
The effects of cement production on the elemental composition of soils in the neighborhood of two cement factories in Nigeria have been investigated using the XRF and PIXE/RBS techniques. The concentration of 21 elements viz:-Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Pb, As, Zr, Rb and Br, were determined in about 30 samples. Calcium, P, S, Cr, Ni, Cu and Zn, were found to be relatively enriched in the soils of the cement factory premises. Calcium, a cement marker element, was found to be well correlated with Mg, S, Fe, Ni and Cu in the soils, and inversely proportional to the Si and Ti concentrations. From Ca/Si ratios and enrichment factors of the marker elements, it was found that soil contamination due to cement drops sharply with distance from the factories, and with increasing depth from the surface.  相似文献   
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覆土厚度是水稻种绳直播机工作质量的主要评价指标之一。为提高种绳直播机的性能,通过正交试验研究影响覆土厚度的主要因素。经试验分析,得出开沟深度的调节值和机体作业速度为主要影响因素。  相似文献   
5.
Lunasin is a novel, cancer-preventive, anti-inflammatory and cholesterol-reducing peptide that was originally isolated from soy and later from barley, wheat and rye. We report the first discovery of lunasin in triticale (X Triticosecale Wittmack). Moreover, we report first data of lunasin content in winter rye and wheat genotypes grown in Northern Europe. These data are novel as previously published data on finding of lunasin in cereals were obtained in genotypes grown in Korea. Lunasin content was uncovered using a previously published procedure for isolation from cereals and identified by LC-MS/MS assay. We found that triticale was the most lunasin-rich cereal, with the tested genotypes displaying the following trend in lunasin content: genotype 0002-26 > Dinaro > DSGU 10/94 > 0213-22 > 0317-14 > 0006-31. The greatest lunasin content was 6.46 mg/g in the grain of triticale genotype 0002-26. In comparison, the highest lunasin content in rye variety Dankovske Diament was 1.5 mg/g, and the highest lunasin content in the winter wheat variety Fredis was 0.23 mg/g. We conclude that triticale can play a significant role as functional food, with great potential for the use of triticale products in human and animal diets.  相似文献   
6.
在免耕、深耕、传统耕作花生试验田调查杂草种类、数量、鲜重和花生产量。结果表明,3种耕作模式花生田杂草的种类和优势种群基本相同,但杂草发生密度不同;在花生花期和结荚期,3种耕作模式中免耕田杂草鲜重最低,传统耕作田最高;免耕和深耕耕作模式下花生产量均比传统耕作方式提高,其中免耕较传统耕作增产10.74%,深耕增产6.27%。  相似文献   
7.
甘蓝型化学杀雄杂交油菜品种秦优33种子纯度的SSR鉴定   总被引:2,自引:0,他引:2  
为了准确、稳定、高效的鉴定杂交油菜纯度,本研究在简单重复序列(SSR)琼脂糖电泳高效标准分析技术体系基础上,通过对479对引物筛选,获得扩增效果好、条带清晰稳定、可将化学杀雄杂交油菜品种秦优33及其亲本系三者皆可有效区别的SSR引物3对.利用其中的SA332引物对三者的高纯单株分别进行了单株验证,结果表明,三者的SSR单株图谱表现与各自的标准图谱的一致性对应率极高,分别达到了98%、99.33%和96.67%.同时利用SA332和SA85两对引物对秦优33生产商品种种子进行了实用化检测,并和大田形态结果进行了一一定株吻合率比对,结果显示,两对引物与大田的单株吻合率皆能达到96%以上,最高可达98.67%;两引物之间在两样品上的一致性偏差比较仅为0.67%和2.67%; 150株室内较小检验群体和大田300株以上较大考察群体的纯度偏差仅为-2.19%到3.76%.研究结果表明,室内SSR的鉴定结果和大田种子纯度的实际表现基本一致,可用于油菜杂种纯度的鉴定.  相似文献   
8.
1995年生产的杂交水稻种子与1996年生产应用需要约多余7.5万t,种子隔年贮藏以塑料小包装后,再放入低温低湿仓库或利用军用仓库贮存,至翌年或第3年发芽率还很高,可避免损失。  相似文献   
9.
应用SSR鉴定化学杀雄杂交油菜秦杂油19种子纯度的研究   总被引:1,自引:0,他引:1  
为有效建立化杀杂交油菜品种的纯度鉴定方法,本研究利用简单重复序列(SSR)技术,对秦杂油19及其亲本进行了分子鉴定,从800对SSR引物中筛选出了5对带型清晰、扩增效果好且能将亲本与杂交种完全区别的引物。利用其中的SR767和SR790两引物对三者的单株进行了分析验证,三者的扩增图谱与标准图谱对应率极高,分别为97.33%、98.00%、100%和98.67%、96.67%、98.00%;利用两对SSR引物对秦杂油19的栽培品种进行分别鉴定和比较研究,结果显示两对不同引物的SSR分子鉴定结果的单株吻合率96.67%~98.32%之间,结果表明,利用SSR分子标记可以用于杂交油菜纯度鉴定。  相似文献   
10.
为实时准确监测土壤的水吸力,基于土壤张力计电阻应变原理,研制开发一款结构简单、价格低廉的土壤张力传感器。传感器标定与误差分析结果表明,该传感器的精度与灵敏度较高,能够满足设计要求。  相似文献   
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