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1.
The aim of this study was to evaluate the effects of dietary supplementation of Morinda lucida leaf meal (MLLM) on the haematology, biochemical and organ changes of broiler chickens. One hundred and ninety-eight day-old Marshall broiler chicks were completely randomised into 6 treatments in a 3?×?2 factorial arrangement of three levels of M. lucida leaf meal supplementation (0, 0.1 and 0.2 g/kg) with or without medication. The treatment consisted of both negative (without MLLM and routine medication) and positive (containing no MLLM but with routine medication) control groups while each treatment was replicated thrice. MLLM-supplemented diets and routine medication decreased (p?<?0.05) the white blood cell count compared to the negative control. Dietary supplementation with MLLM in combination with normal routine medication increased (p?<?0.05) total serum protein when compared with treatment group without MLLM and routine medication. Dietary supplementation with MLLM and routine medication reduced (p?<?0.05) serum creatinine concentration of the broiler chickens. Birds fed with 0.2 g/kg MLLM supplement coupled with medication and those on negative control had higher (p?<?0.05) creatinine values. Serum enzyme activities reduced (p?<?0.05) following supplementation. MLLM supplementation recorded no significant effect (p?>?0.05) on the liver, kidney, heart and gizzard. M. lucida leaf meal can be compared to routine medication for improved health status of broiler chickens. Dietary inclusion with 0.1 g/kg MLML combined with routine medication could be used in producing healthy and safe chickens.  相似文献   
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This experiment was carried out to evaluate the effect of reduced dietary crude protein (CP) levels supplemented with or without exogenous phytase on growing pigs. Six dietary treatments arranged in a 3 × 2 factorial arrangements of 3 CP levels (containing 14%, 16%, and 18% CP) supplemented each with or without 5,000 FTU/g phytase enzyme. Thirty growing pigs (average weight of 17.80 ± 0.10 kg) were allotted to the six dietary treatments in a complete randomized design. The final weight, daily weight gain, and feed conversion ratio (FCR) increased significantly with increasing CP levels. While, phytase supplementation improved (p = .044) FCR in pigs. Total solid and volatile solid content of the slurry were higher (p = .001) in pigs fed 14% and 16% CP diets supplemented with phytase when compared with other treatment groups. Concentration of methane gas emitted was lowest (p = .001) in the slurry of pigs fed 14% CP diet with or without phytase and those fed 16% CP diet with phytase supplementation. In conclusion, reduction in dietary CP levels resulted in reduced weight gain and poor FCR. While, reduced CP with phytase supplementation reduced concentration of methane gas emitted.  相似文献   
4.
The aim of this study was to investigate the course of expression of platelet‐activating factor (PAF), PAF‐receptor (PAF‐R), epidermal growth factor (EGF), EGF‐R, vascular endothelial growth factor (VEGF), VEGF‐R1 and VEGF‐R2 in uterine tissue during canine pregnancy. For this purpose, 20 bitches were ovariohysterectomized at days 10–12 (n = 10), 18–25 (n = 5) and 28–45 (n = 5) days after mating, respectively. The pre‐implantation group was proven pregnant by embryo flushing of the uterus after the operation, the others by sonography. Five embryo negative, that is, non‐pregnant, bitches in diestrus (day 10–12) served as controls. Tissue samples from the uterus (placentation sites and horn width, respectively) were excised and snap‐frozen in liquid nitrogen after embedding in Tissue Tec®. Extraction of mRNA for RT‐PCR was performed with Tri‐Reagent. In the embryos, mRNA from all factors except VEGF was detected. In the course of pregnancy, significantly higher expression of PAF and PAFR as well as VEGF and VEGFR2 during the pre‐implantation stage than in all other stages and a strong upregulation of EGF during implantation were characteristic. The course of EGF was in diametrical opposition to the course of the receptor. These results point towards an increased demand for VEGF, EGF and PAF during the earliest stages of canine pregnancy.  相似文献   
5.
Mesenchymal stem cells (MSC) are multipotent progenitor cells defined by their ability to self‐renew and give rise to differentiated progeny. Previous studies have reported that MSC may be induced in vitro to develop into different types of specialized cells including male gametes. In vitro gamete derivation technology has potential applications as an alternative method for dissemination of elite animal genetics, production of transgenic animals and conservation of endangered species. This study aimed at investigating the in vitro effect of BMP4, TGFβ1 and RA on the potential for germ cell (GC) differentiation of bovine foetal MSC (bfMSC) derived from bone marrow (BM). The effect of BMP4, TGFβ1 and RA was analysed on the expression of pluripotent, GC and male GC markers on bfMSC during a 21‐day culture period. bfMSC cultured under in vitro conditions expressed OCT4, NANOG and DAZL, but lacked expression of mRNA of VASA, STELLA, FRAGILIS, STRA8 and PIWIL2. Treatment with exogenous BMP4 and TGFβ1 induced a transient increase (p < .05) in DAZL and NANOG mRNA levels, respectively. However, exposure to RA was more effective in increasing (p < .05) expression of DAZL and regulating expression of OCT4 and mRNA levels of NANOG. These data suggest that bfMSC may possess potential for early GC differentiation, where OCT4, NANOG and specially DAZL may play significant roles in controlling progression along the GC lineage.  相似文献   
6.
彭海兰  姬拉拉  黄兴敏  王健健 《核农学报》2022,36(12):2482-2489
为明确大气CO2浓度升高及氮肥施用对薏苡(Coix lacryma-jobi L.)苗期营养元素吸收运输的影响,本研究以兴仁白壳薏苡为试验材料,采用盆栽控制试验,通过人工气候箱模拟CO2浓度升高,探究薏苡各器官中营养元素对CO2浓度升高和施用氮肥的响应。结果表明,CO2浓度升高使薏苡根中TOC含量显著增加15.82%;叶、茎中TP含量显著增加18.98%、29.41%(P<0.05);叶、根中N含量显著减少8.15%、8.31%(P<0.05);叶、茎、根中K含量无显著差异。施氮使薏苡叶、茎、根中N含量显著增加19.52%、28.42%、23.29%;叶、茎中TP含量显著增加14.60%、51.96%(P<0.05);根中K含量显著减少22.57%(P<0.05);叶、茎、根中TOC含量无显著差异。两者交互作用下,薏苡茎、根中N含量显著增加6.49%、8.99%;叶中TP含量显著增加15.33%(P<0.05);叶中N含量显著减少4.22%;叶、茎中K含量显著减少18.47%、33.25%(P<0.05);叶、茎、根中TOC含量无显著差异。在CO2浓度升高条件下,薏苡叶片中中量元素S和微量元素Cu、Zn、Ni含量,分别显著减少18.06%、54.01%、37.96%、50.99(P<0.05);而茎中Mn、Cu、Zn、Ni含量,分别显著增加90.20%、70.55%、46.80%、149.50%(P<0.05)。CO2浓度升高能促进Mg、S根向茎的运输以及Zn、Mn茎向叶的运输,施用氮肥能促进Fe茎向叶的运输。综上所述,CO2浓度升高和氮肥施用会影响薏苡不同器官矿质离子的吸收及选择性运输能力,从而维持植物体内营养元素平衡。本研究结果可为深入认识未来大气环境变化下,薏苡对营养元素的需求变化特征,以及薏苡栽培中施肥策略的选择提供科学依据。  相似文献   
7.
Lightning dart leaders and return strokes have been recorded in daylight with both good spatial resolution and good time resolution as part of the Thunder-storm Research International Program. The resulting time-resolved photographs are apparently equivalent to the best data obtained earlier only at night. Average two-dimensional return stroke velocities in four subsequent strokes between the ground and a height of 1400 meters were approximately 1.3 x 10(8) meters per second. The estimated systematic error is 10 to 15 percent.  相似文献   
8.
This study assessed ecological and socio-economic impacts of a participatory forest management project in the Republic of Benin. The study focused on the Wari-Maro Forest Reserve and the ‘Projet d’Aménagement des Massifs Forestiers’ five years after its completion. A forest inventory was carried out using 37 square plots of 729 m2 each to characterise the population structure of two types of plantations established: plantations with exotic species and plantations with native species. In addition, individual surveys were conducted with local households, organs of joint forest management and forestry officers to evaluate their perceptions about the participatory management of the plantations. Finally, the sustainability of the participatory management was assessed with an established rating system. Results showed that plantations with exotic species were more successful than plantations with native species. Local communities argued that they have not been involved in the plantations design but only in the implementation step and that their standards of living have decreased after the project completion. The rating system used showed that the participatory management of plantations had a short-term sustainability. The findings suggest that future projects should be designed and implemented with better participation of local communities as full partners.  相似文献   
9.
Crop wild relatives (CWR) are wild species that are more or less genetically related to crops that can be used to introgress useful genes for improvement of productivity, resistance to biotic and abiotic stresses and quality of cultivated crops. They are important in crop improvement to achieve food security for an increasing population and to overcome the challenges caused by climate change and the new virulence of major diseases and pests. These genetic resources are increasingly threatened in their natural habitats through over-exploitation and land reclamation and degradation. Therefore, their efficient and effective conservation would be taxonomically and genetically valuable and will contribute to maintaining and promoting the sustainability of crop diversity, facilitating agricultural production and supporting the increasing demand for food, feed and natural resources. A checklist of 5780 Crop Wild Relatives (CWR) taxa from North Africa was obtained using the CWR Catalogue for Europe and the Mediterranean (PGR Forum). Of which consists 76% of the flora of North Africa. The checklist contains 5588 (~97%) native taxa and 192 introduced. Families with higher taxa richness are Fabaceae, Asteraceae, and Poaceae. These three families constitute more than 33% of the total taxa included in the checklist. About 9% (502) CWR taxa identified as a priority for conservation in North Africa using four criteria, the economic value of the crop, the relatedness degree of wild relatives to their crop, threat status using IUCN red list assessment, and finally the centre of origin and/or diversity of the crop. Of these, 112 taxa were assigned high, 268 medium and 122 low priorities for effective conservation. Those assessed as threatened using IUCN Red list and national assessment represent approximately 2% (119 taxa) of the CWR in the region. However, 21 taxa are assessed as critically endangered (CR), 53 as endangered (EN), and 45 as vulnerable (VU). Wild relatives of some globally important crops are present, with those related to wheat (Triticum aestivum L. and T. durum L.) and barley (Hordeum vulgare L.) among the highest priority crops for the North Africa region. Amongst CWR assessed as threatened, only 8 (6.7%) CWR are related to food crops, Avena agadiriana B.R. Baum. et G. Fedak (VU), A. atlantica B.R. Baum et G. Fedak (VU), A. murphyi Ladiz. (EN), Beta macrocarpa Guss. (EN), Olea europaea subsp. maroccana Guss. (VU), Rorippa hayanica Maire (VU) and Aegilops bicornis (Forssk.) Jaub. et Spach (VU). The wild relative of Safflower Carthamus glaucus M. Bieb is restricted to Egypt and Libya and assessed as rare in Egypt. The information available about the conservation and threat status of CWR in North Africa still lags behind, and more investigations are required.  相似文献   
10.
氮磷缺乏对薏苡生长及其生理特性的影响   总被引:1,自引:0,他引:1  
以贵州省黔西南州兴仁县薏苡为试材,采用沙培盆栽方式设置对照(全素营养)、缺氮、缺磷、缺氮磷4个处理,测定分析了薏苡生长前期各形态指标、叶绿素含量、抗氧化酶系统及可溶性糖的含量,探讨氮磷元素缺乏对薏苡生长及生理特性的影响,以期提高薏苡的产量及品质。结果表明:1)缺氮、缺磷、缺氮磷均显著降低薏苡株高、根长、总叶片数、比叶面积及叶绿素含量,导致总生物量较对照分别降低80.65%、77.88%、91.24%;2)缺氮、缺磷、缺氮磷显著增加丙二醛(MDA)含量及过氧化氢酶(CAT)活性,缺氮时过氧化物酶(POD)活性降低14.29%,缺磷、缺氮磷时活性升高;3)薏苡可溶性糖含量在缺磷时较对照显著增加102.00%,缺氮和缺氮磷时可溶性糖含量分别较对照显著降低54.35%、34.59%。缺素处理总体上抑制了薏苡的生长,且缺氮磷比单独缺氮、缺磷对薏苡生长及生理的抑制作用更明显。  相似文献   
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