Evaluation of rabbit excreta as an ingredient in broiler diets

1. Dry rabbit excreta were found to contain 188.1 g crude protein, 6.6 g non‐protein nitrogen, 0.3 g ammonia, 89.8 g moisture, 8.0 g ether extractives, 135.2 g crude fibre, 266.9 g ash and 19.18 MJ gross energy/kg. Methionine and lysine contents were 3.95 and 4.29 g/100 g protein, respectively.

2. In one experiment, 0, 50, 100 or 200 g rabbit excreta/kg were substituted for maize in a broiler diet. Chickens receiving the diet containing 200 g rabbit excreta/kg gained significantly less weight to 8 weeks of age than those receiving other diets.

3. In a second experiment, 0, 100, 150 or 200 g rabbit excreta/kg were substituted primarily for maize in a broiler diet to provide equal energy and protein contents. Weight gains to 8 weeks of birds receiving these diets did not differ significantly. The uncorrected metabolisable energy content of the excreta was 9.15 MJ/kg.

4. There were no gross pathological changes in the birds fed on the experimental diets.     

Potential Use of 3D CORAGRAF-Loaded PDGF-BB in PLGA Microsphere Seeded Mesenchymal Stromal Cells in Enhancing the Repair of Calvaria Critical-Size Bone Defect in Rat Model

Our previous study evidenced that the 3D CORAGRAF loaded with PLGA microsphere constitutes PDGF-BB can support cell attachment and proliferation and can induce an osteogenic commitment of mesenchymal stromal cells in the in vitro condition. However, how this construct can perform in pathophysiological conditions in terms of repairing critical bone defects is yet to be understood. A study was therefore conducted to investigate the regeneration potential of calvaria critical-size defects using CORAGRAF + PLGA with PDGF-BB + mesenchymal stromal cells (MSCs) in a rat model. A 5 mm critical bone defect was created on calvaria of 40 male Sprague-Dawley rats. CORAGRAF incorporated either with or without PDGF-BB and seeded with rat bone-marrow-derived MSCs was implanted at the defect region. The bone regeneration potential of implanted constructs was assessed using micro-CT imaging and histological staining in weeks 4 and 8. The micro-CT images indicated a significant closure of defects in the cranial bone of the rats treated with 3D CORAGRAF + PLGA with PDGF-BB + MSCs on week 4 and 8 post-implantation. This finding, further supported with the histology outcome where the rat cranial defect treated with CORAGRAF + PLGA with PDGF-BB + MSCs indicated neo-bony ingrowth with organized and mature bone-like morphology as compared with other groups. The previous in vitro results substantiated with our pre-clinical findings demonstrate that the combination of CORAGRAF + PLGA with PDGF-BB + MSCs could be an ideal construct to support bone regeneration in critical bone defects. Hence, this construct can be further investigated for its safety and efficacy in large animal models, or it can be skipped to human trial prior for commercialization.     

不同倍性西瓜的叶表皮微形态特征比较

扫描电镜观察结果表明,随着西瓜倍性的增加,叶片保卫细胞和表皮细胞增大,叶片单位面积上的气孔和表皮细胞的数目减少,细胞的大小与西瓜倍性呈正相关,单位面积上的细胞数目与西瓜倍性呈负相关。通过FDA荧光记数法观察,4x、3x和2x的叶片保卫细胞中的叶绿体数目分别为19.9±3.4,15.9±2.2,11.5±1.5,其比例约为4∶3∶2,与西瓜的倍性一致。根据此方法可以快速有效地对西瓜倍性进行早期鉴定。     

文心兰花梗外植体形态建成初步研究

通过对文心兰花梗外植体的诱导培养及其形态建成途径观察研究发现,外植体通过不定芽（器官型）和愈伤组织成芽（器官发生型）以及PLB途径,最终发育形成完整植株。     

Phosphate solubilising bacteria

Most reports of the studies on solubilisatioh of phosphate in liquid culture and soil suggested that organic acids produced by microorganisms are responsible for promoting the dissolution of phosphate. Sperber (11, 12), Louw and Webley (7) and Duff, Webley and Scott (2) studied the production of acids by cultures of some phosphate dissolving fungi. actinomycetes and bacteria and observed that among the acids produced in liquid medium, hydroxy carboxylic acids such as lactic and 2-ketogluconic acids were responsible for solubilisation of phosphates. In the present studies, apart from the culture of Bacillus megaterium var. phosphaticum isolated from phosphobacterin which had been obtained from USSR. Indian strains of Bacillus megaterium, Bacillus circulans and Escherichia freundii isolated and identified by Sundara Rao and Sinha (13) were used. These studies were undertaken to find out different types of nonvolatile acids produced in Pikovskaya's (9) liquid medium.     

Internal Mechanisms of Plant Adaptation to Aluminum Toxicity and Phosphorus Starvation in Three Tropical Forages

Many tropical forage grasses and legumes grow well in acid soils, adapting to excess aluminum (Al) and phosphorus (P) starvation stresses by using mechanisms that are still unclear. To determine these mechanisms, responses to Al toxicity and P starvation in three tropical forages were studied: two grasses, Brachiaria hybrid cv. ‘Mulato’ (B. ruziziensis clone 44-06 × B. brizantha cv. ‘Marandú’) and Andropogon gayanus, and one legume, Arachis pintoi. The tropical grasses tolerated high levels of Al toxicity and P starvation, with the Brachiaria hybrid maintaining very low levels of Al concentration in shoots. ²⁷Al Nuclear Magnetic Resonance spectroscopy (NMR) analysis revealed that, in the Brachiaria hybrid, Al makes complexes with some ligands such as organic-acid anions in the root symplast. The forages probably adapted to P starvation through high P-use efficiency. These experiments provide the first direct evidence we know of that organic acid anions within root tissue help detoxify Al in non-accumulator species such as the Brachiaria hybrid.     

RAPD and ISSR fingerprinting in cultivated chickpea (<Emphasis Type="Italic">Cicer arietinum</Emphasis> L.) and its wild progenitor <Emphasis Type="Italic">Cicer reticulatum</Emphasis> Ladizinsky

Detection of genetic relationships between 19 chickpea cultivars and five accessions of its wild progenitor Cicer reticulatum Ladizinsky were investigated by using RAPD and ISSR markers. On an average, six bands per primer were observed in RAPD analysis and 11 bands per primer in ISSR analysis. In RAPD, the wild accessions shared 77.8% polymorphic bands with chickpea cultivars, whereas they shared 79.6% polymorphic bands in ISSR analysis. In RAPD analysis 51.7% and 50.5% polymorphic bands were observed among wild accessions and chickpea cultivars, respectively. Similarly, 65.63% and 56.25% polymorphic bands were found in ISSR analysis. The dendrogram developed by pooling the data of RAPD and ISSR analysis revealed that the wild accessions and the ICCV lines showed similar pattern with the dendrogram of RAPD analysis. The ISSR analysis clearly indicated that even with six polymorphic primers, reliable estimation of genetic diversity could be obtained, while nearly 30 primers are required for RAPD. Moreover, RAPD can cause genotyping errors due to competition in the amplification of all RAPD fragments. The markers generated by ISSR and RAPD assays can provide practical information for the management of genetic resources. For the selection of good parental material in breeding programs the genetic data produced through ISSR can be used to correlate with the relationship measures based on pedigree data and morphological traits to minimize the individual inaccuracies in chickpea.     

水肥耦合对当归产量和品质的影响效应研究

探索水肥耦合对当归品质和产量的影响效应,为当归GAP规范化种植中的水肥调控提供理论依据。采用水肥双因素试验,通过二元二次多项式拟合灌水量、施肥量与当归产量和主要品质指标（阿魏酸含量）的关系,建立影响效应模型,并对其进行检验分析和相关性分析。结果表明：在灌水一定的情况下,随着施肥量的增加,当归的产量先增加后减少;在施肥一定情况下,随着灌水量的增加,当归的产量也是先增加后减少,当归的最高产量出现在中水中肥区,即灌水量1073.97 m3/hm2,施肥量808.97 kg/hm2,最大产量为15804.36 kg/hm2;在灌水量一定的条件下,随着施肥的增加当归的阿魏酸含量先增加后降低,在施肥量一定的条件下,随着灌水量的增加当归的阿魏酸含量也是先增加后降低,当归的阿魏酸含量最高出现在中高水中高肥区,即灌水量1491.42 m3/hm2,施肥量863.55 kg/hm2,阿魏酸最高含量为2.41 mg/g。合理有效的灌溉施肥使当归达到优质高产。     

干旱地区喷洒水利用系数的田间试验研究

为了科学地评价喷灌在干旱地区的适宜性,在内蒙古包头春小麦生育期内对喷洒水利用系数进行了监测,结果指出,通过选择适宜的灌溉时间,喷洒水利用系数可以达到0.85以上。对影响喷洒水利用系数的环境因素进行分析后得出,风速的影响最大,相对湿度次之,气温的影响很小;在此基础上建立了喷洒水利用系数与上述3因子之间的回归模型。为了估算整个灌溉季节的喷洒水利用系数,对所研究地区1991～2001年灌溉季节(4～9月份)内的日平均风速进行了统计分析,发现不大于3m/s的日数占灌溉季节总日数的90%以上,因此,选择日平均风速不大于3m/s的时间灌溉可以满足作物的需水要求,这种情况下,整个灌溉季节的喷洒水利用系数可以达到0.83。由此可见,在条件与包头类似的干旱地区,从提高水的利用率的角度出发,发展喷灌也是适宜的     

猪流行性腹泻IgA、IgG抗体与PEDV抗原相关性研究

为了研究仔猪所吮乳汁中IgA抗体水平与乳汁中PEDV感染情况,探讨母猪免疫猪流行性腹泻疫苗后乳汁与血清中IgA、IgG抗体水平的相关性,临床采集多家规模化猪场母猪群乳汁、血清样品以及发病仔猪所吮母猪乳汁样品。采用实验室已经建立的IgA、IgG抗体ELISA方法,检测临床上猪流行性腹泻疫苗免疫后IgA抗体与IgG抗体的相关性,同时采用RT-PCR方法检测发病仔猪所吮乳汁中PEDV感染情况。结果表明,免疫猪流行性腹泻活疫苗后母猪乳汁中IgA抗体水平与血清中IgA、IgG抗体水平呈现很好的正相关性;当发病仔猪所吮母猪乳汁IgA抗体检测结果为阴性时,其PEDV抗原检测结果为阳性;乳汁IgA抗体检测结果趋于阳性样品临界值时,其PEDV抗原检测结果亦为阳性。结论:乳汁中低水平的IgA抗体很难有效地保护仔猪抵御PEDV感染;乳汁中IgA抗体与血清IgA、IgG抗体呈现很好的相关性,且乳汁中IgA抗体水平远远高于血清;通过IgG抗体水平可以间接反映乳汁中的IgA抗体水平,在初乳样品采集难度较大的情况下,可用于间接评估猪流行性腹泻免疫保护水平。