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1. Different concentrations of non-phytate phosphorus (NPP, 2.5, 3.0, 3.5, 4.0 and 4.5 g/kg diet) were given to broilers (8 to 42 d of age) to establish regressions between dietary NPP concentration and body weight gain and tibia ash content. Second and third experiments were conducted to study the feasibility of utilisation of different phosphatic fertilisers [ammonium phosphate (AP), ammonium polyphosphate (APP), single super phosphate (SSP), NPK (17:17:17, NPK) and NP (28:28:0, NPK)] in commercial broilers (8 to 42 d) and White Leghorn layers (252 to 364 d). 2. Phosphatic fertilisers were incorporated both in broiler (10 g calcium and 4.5 g NPP/kg) and layer (35 g calcium and 3.5 g NPP/kg) diets by replacing dicalcium phosphate (DCP) in toto. 3. The logarithmic curves obtained for predicting the body weight gain and tibia ash content at different levels of NPP used in experiment 1 were Y = 156.27 + 2,468.8 logX (r2= 0.958) and Y = 530.82 + 144.26 log X (r2 = 0.916), respectively. 4. Body weight gain and food intake in broilers given APP- or NP-supplemented diets were comparable to these in the DCP-fed group. Feeding of NPK, AP or SSP resulted in significant depression in weight gain and food intake and high excreta moisture content. Food/gain, Ca and P contents in tibia ash and serum were not influenced by the use of phosphatic fertilisers as P sources in broiler diets. 5. Tibia ash content in broilers fed on diets containing fertilisers was either similar to or significantly higher than that in the DCP-fed group. Broilers on AP or SSP retained more P and had higher tibia ash content than those on DCP. AP, SSP or NPK caused degenerative and necrotic changes in liver, kidney and intestine of broilers. 6. Relative bio-availability of P from APP or NP was better for body weight gain than AP, SSP or NPK, while the reverse was true for bone calcification. 7. APP and NP gave hen-d egg production similar to that of DCP-fed layers. Food intake was significantly reduced in layers fed on diets containing fertilisers. However, food/egg mass, egg weight and serum Ca and inorganic P contents were not influenced by inclusion of fertilisers in layer diets. 8. Except for AP, inclusion of fertilisers in layer diets reduced shell weight and shell thickness compared with the DCP-fed group. However, no apparent eggshell defects were found which could be attributable to diet. 9. Results of these experiments suggest that APP and NP can be used as the sole source of P both in broiler and layer diets, replacing DCP in toto. However, when utilising these P sources in layers, due attention should be given to shell quality. Fertilisers containing high F (AP and SSP) or K (NPK) reduced performance in broilers and layers and caused microscopic changes in liver, kidney and intestine in broilers. 相似文献
44.
A rapid MTT colorimetric assay to assess the proliferative index of two Indian strains of Theileria annulata 总被引:3,自引:0,他引:3
Saravanan BC Sreekumar C Bansal GC Ray D Rao JR Mishra AK 《Veterinary parasitology》2003,113(3-4):211-216
A study was undertaken to compare the proliferative index of macroschizont-infected lymphoblastoid cells of two Indian strains [Izatnagar (IZT) and Parbhani (PBN)] of Theileria annulata by an in vitro MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide], colorimetric assay. Culture conditions were standardized to define the optimal cell concentration in 96-well microculture plates to yield nearly 100% living cells for measurement of the metabolized formazan activity. A cell concentration of 1.5x10(5) cells/ml was found to be optimal for effective discrimination of the parasite strains. On the basis of conversion of MTT by the actively proliferating lymphoblastoid cells, the PBN strain of T. annulata stimulated a 2.5-fold increase in formazan activity in comparison to the IZT strain. The in vitro MTT assay was found to be a simple and convenient method for assessing the cell activation rate and growth, obviating the need for radioactive material for the assay. The results of the proliferation assay are discussed in relation to previously documented information on the biological characteristics of this important pathogen of cattle. 相似文献
45.
1. To detect polymorphism in various quail lines, Randomly Amplified Polymorphic DNA (RAPD) markers were tested and were found to be effective. 2. Twenty decamer primers were selected at random and tested, and 6 of these generated distinct polymorphic patterns between the quail lines. 3. Out of a total of 60 bands amplified using 6 selected primers, 19 (31.7%) were found to be polymorphic. 4. Genetic similarity within the lines ranged from 0.726 in HBW to 0.836 in KLQ. 5. Genetic similarity estimates between the populations ranged from 0.709 to 0.808. 相似文献
46.
发酵血粉代替豆粕对育肥猪的影响 总被引:1,自引:0,他引:1
试验采用单因子试验设计,选用40kg左右的肥育猪40头,随机分成4组,每组5个重复,每个重复2头,分别饲喂基础日粮(对照组)和用发酵血粉分别替代基础日粮中的豆粕50%(试验Ⅰ组)、75%(试验Ⅱ组)和100%(试验Ⅲ组)等4种试粮,进行60d试验。结果表明:与对照组相比,试验Ⅱ组和试验Ⅲ组的末重与日增重均有显著提高(P<0.05),其中日增重分别提高11.33%和14.34%;与对照组相比,试验Ⅱ组料重比显著降低(P<0.05),其它各组差异不显著(P>0.05)。代谢试验表明:与对照组相比,蛋白质的消化率,氮沉积量(g/d)、氮沉积率(g/kgBW0.75)都显著提高(P<0.05)。随着替代的比例增加,经济效益改善呈上升趋势,试验Ⅱ组和试验Ⅲ组分别比对照组多赢利23.11%和28.29%。 相似文献
47.
浅谈奶牛子宫内膜炎 总被引:4,自引:0,他引:4
随着人们生活水平的不断提高。我国乳业在迅速的发展,奶牛养殖业也在大规模地扩增。奶牛的不孕症是奶牛四大类疾病之一,而子宫内膜炎是奶牛不孕症的主要原因之一。子宫内膜炎是奶牛生产中的常见病,一旦发生,奶牛配种困难或长期不孕,导致养殖效率低,甚至提前淘汰。抓好子宫内膜炎的预防和治疗,对促进奶业增效、奶农增收意义重大。据报道,我国奶牛子宫内膜炎型不孕症占成年母牛不孕症的17%以上。每年美国有12.19%的奶牛患有繁殖疾病。经济损失近2.5亿美元;英国报道的不孕牛中约95%是由于子宫内膜炎引起的。在国内,1984~1988年,中国农业科学院中兽医研究所对10个城市30个奶牛场的10495头适龄母牛的调查表明,产后患子宫内膜炎的有2107头.发病率为20.08%。瞿自明等1983~1985年对北京、上海、南宁、兰州等16个城市41个奶牛场调查了9754头适龄奶牛,有1684头发生子宫内膜炎,约占17.26%,占不孕牛的68.34%。由此可见,奶牛子宫内膜炎对畜牧业所造成的经济损失是相当严重的。 相似文献
48.
试验分析了1号染色体上2个SNP位点(rs15279778、rs14837036)的多样性及其与鸡生长性状的相关性.结果表明:rs15279778和鸡的早期生长性状显著相关,其对表型方差的贡献率均值为11.65%.rs15279778可应用于鸡早期生长性状的标记辅助选择. 相似文献
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50.
调查表明,东乡野生稻原产保护地蜘蛛群落优势科为狼蛛科、跳蛛科、管巢蛛科、球蛛科、肖蛸科,相对丰度分别为0.5010、0.1529、0.0785、0.0657、0.0559、0.0399、0.0392,其丰盛度总和达0.8540,构成了蜘蛛群落的主要成分;巨蟹蛛科为稀有科。优势种为拟水狼蛛、沟渠豹蛛、中华狼蛛、横窝希蛛、黄斑纯蛛、白纹舞蛛、微菱头蛛、柔弱锯螯蛛,其相对丰盛度分别为0.1802、0.1209、0.0833、0.0589、0.0484、0.0445、0.0417、0.0413,丰盛度总和达0.6192,埃比熊蛛等为稀有种。调查还表明,不同时期的物种丰富度变化不明显,但在6~7月间,群落中物种丰富度相对较高,各物种种群发生数量大,分布相对均匀,优势种不突出,群落结构较合理,均匀度和多样性指数较高。 相似文献