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1.
不同阶段猪用颗粒饲料物理性能的对比分析   总被引:1,自引:0,他引:1       下载免费PDF全文
对某饲料厂不同阶段猪用4种颗粒饲料的物理性能包括直径、长度、硬度、容重、含粉率和耐久性指数(Pellet Durability Index, PDI)等进行测定,对结果进行归类总结并采用统计学的方法参照有关标准进行分析。结果表明,4种颗粒饲料直径在2.87~3.94 mm之间,母猪料直径最大,小猪料最小,两两之间差异显著(P<0.05),而且随着猪只年龄的增加,颗粒饲料的直径呈递增趋势。颗粒长度在8.62~11.94 mm之间,以大猪料最长,小猪料最短,长径比偏高。颗粒硬度在3.86~6.47 kg之间,以大猪料最大,小猪料最小,中小猪料显著低于大猪料和母猪料(P<0.05),只有小猪料符合有关要求。颗粒容重在576.7~614.6 g/L之间,母猪料最大,小猪料最小,两两之间差异显著(P<0.05),与直径呈相同的增减趋势。含粉率以小猪料最大,且只有小猪料与大猪料之间差异显著(P<0.05)。颗粒PDI以大猪料最大,小猪料最小,各阶段猪料的含粉率和PDI均符合有关要求。建议饲料厂家注重颗粒饲料物理性能指标的控制,调整饲料配方和工艺参数,不断改进颗粒饲料的质量。  相似文献   
2.
Plants have developed different mechanisms to absorb and solubilize phosphorus (P) in the soil, especially in environments with low P availability. This study evaluated the effects of different winter cover crops on soil P availability in a clayey subtropical (Hapludox) soil receiving soluble P fertilizer and a rock phosphate applied to the summer crop, under no‐tillage. The experiment was carried out over 3 yrs (2009–2011) with five different cover crop species: common vetch, fodder radish, ryegrass, black oat, white clover and fallow as control. The soil was sampled after the third year of cover crop cultivation and analysed for inorganic and organic P forms according to the well‐established Hedley fractionation procedure. Phosphate fertilizers promoted accumulation of both labile and nonlabile P pools in soil in the near surface layer, especially under rock phosphate. Fertilizer applications were not able to change P fractions in deeper layers, emphasizing that the Brazilian clayey soils are a sink of P from fertilizer and its mobility is almost nil. Although the cover crops recycled a great amount of P in tissue, in a short‐term evaluation (3 yrs) they only changed the content of moderately labile P in soil, indicating that long‐term studies are needed for more conclusive results.  相似文献   
3.
采用酶解西番莲汁为原料,以麦芽糊精为助干剂,通过喷雾干燥法制备了西番莲粉,研究麦芽糊精添加量、进风温度、进料流量和进料浓度对西番莲粉产率、VC含量和含水率的影响。在单因素试验的基础上,采用正交试验优化了西番莲粉喷雾干燥工艺参数。结果表明,西番莲粉喷雾干燥的最佳工艺参数为:麦芽糊精添加量60%(按照喷雾干燥前料液总固形物含量计算),进风温度170℃,进料流量9 mL/min,进料浓度30%,此条件下西番莲粉的产率50.47%,VC含量58.88 mg/100 g,含水率4.8%。制得的产品具有西番莲特有的果香,研究为西番莲的产品多样化提供新的方法和思路。  相似文献   
4.
本文报道以简便易行的方法合成水溶性二甲硝咪唑盐,收率高达95%以上,具工业化应用价值。  相似文献   
5.
原木灵芝孢子粉和浸膏粉中的牛磺酸   总被引:1,自引:0,他引:1  
采用热水提取-磺基水杨酸沉淀法进行样品的前处理,利用氨基酸自动分析仪测定供试样品的牛磺酸含量。试验结果表明,原木灵芝孢子粉和破壁孢子粉中牛磺酸含量分别为8.44mg/100g-9.23mg/100g和7.34mg/100g-7.89mg/100g,而灵芝浸膏粉中牛磺酸含量高达140.82mg/100g-157.38mg/100g.  相似文献   
6.
羔羊全营养代乳粉对羔羊增重影响的试验   总被引:1,自引:0,他引:1  
为了研究羔羊出生后采取人工饲喂代乳粉溶液的效果,对10日龄羔羊称重,以平均日增重与母乳组比较,用t检验方法检验差异显著性。研究结果显示羔羊平均日增重试验组为0.097-0.126kg,母乳组为0.071-0.113kg,二者没有显著差异。在生产中,代乳粉能替代绵羊母乳饲喂羔羊,对多胎品系羊的推广应用以及解决绵羊缺乳、少乳或无乳问题具有重要意义。  相似文献   
7.
酮粉法检测泌乳牛尿酮乳酮的应用研究   总被引:15,自引:1,他引:14  
荷斯坦泌乳牛尿、乳酮体的酮粉法定性试验表明:尿酮阳性率为29.25%,乳酮阳性率为10%。尿、乳阳性牛的血酮、血糖、乳酮、尿酮定量测定表明:酮粉法判定泌乳奶牛亚临床酮病,尿酮阳性反应具有早期、敏感、准确性低的特点。乳酮阳性反应具有准确、敏感性低、方便等特点。二者同时定性检测具有互补作用。  相似文献   
8.
Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity during photosynthetic declination. The content of soluble protein in flag leaf of cv.Wuyujing 3 was higher than that of cv. 97-7, but decreased rapidly in Wuyujing 3. Free amino acids in flag leaf and the thirteenth leaf of Wuyujing 3 started to increase 10 days before the turning point of photosynthetic declination (TPPD), while it occurred just 1-2 days before TPPD in the flag leaf and the thirteenth leaf of 97-7. During reversible phase of photosynthetic declination,endopeptidase activity remained at a low level and increased slightly only in the later part of this phase. Then it rose up rapidly at irreversible decline phase and reached a very high level. For Wuyujing 3, the change in endopeptidase activity in the thirteenth leaf was parallel to that in flag leaf. However, for 97-7, the rapid increase of endopeptidase activity in the thirteenth leaf started later than that of flag leaf. The results implied that the rate of protein breakdown and conversion to transportable nitrogen in leaves of 97-7 was slower than that in leaves of Wuyujing 3 during photosynthetic declination and it led to relatively lower seed setting rate and fully filling grains rate in 97-7. This may be one of the important reasons why 97-7 could not bring the high yield potentiality into play and the findings may be taken into consideration while breeding for high potential varieties in future.  相似文献   
9.
研究一种在纤维板表面进行粉末涂装再转移印花的新工艺.结果表明:纤维板粉末涂装基材预处理采用预热干燥,表面砂光,控制含水率为6%~8%;喷涂上粉量为333.33~388.89 g·m-2;固化条件为180 ℃,15~25 min.采用干燥箱中热转移方式,转移印花温度为(160±10)℃,时间15~20 min.按GB/T 4893-85和GB/T1733-79测试涂膜性能,涂膜附着力等级为2级,耐磨性等级为1级,耐水性合格,耐液性等级为1级.图1表4参9  相似文献   
10.
A field experiment was conducted to find out the critical physiological stages of irrigation schedules inducing better growth, physiological efficiency and seed yield potential of berseem ( Trifolium alexandrinum L., Var. S-99-1). For this purpose eight irrigation treatments were made comprised of four treatments of three irrigation (W1, W2, W3 and W4), three treatments of four irrigation (W5, W7 and W8) and one treatment of five irrigation (W6) at various physiological stages i. e. regeneration, flower initiation, full bloom, seed initiation and advance seed development stage.
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W4, W1 and W7; and further brought out disturbance on the formation of carotene, synthesis of water soluble sugar and translocation of sugar towards reproductive organs during grain development stage. These stresses adversely affected the plant growth and flowering behaviour. The irrigation at seed initiation stage increased the seed yield. Continuous irrigation did not appear to be useful. Thus it can be concluded that irrigation at three critical physiological stages i. e. regeneration, full bloom and seed initiation was found to be essential for obtaining potential seed yield of berseem.  相似文献   
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