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21.
甜菜碱是一种天然化合物,它无毒、无害、性质稳定,又在动物蛋白质和脂肪代谢中起看非常重要的作用。甜菜碱通过影响生长代谢调控轴激素和氨基酸、脂肪代谢对猪生长性能、胴体组成、肉质等产生一定的影响,并达到降低动物脂肪沉积的目的。 相似文献
22.
哈达门国家森林公园游客量动态预测 总被引:3,自引:0,他引:3
根据哈达门国家森林公园的票房数据,应用灰色系统理论建立旅游量灰色动态模型。基此,对哈园游客量进行了中短期预测,其预测检验精度为93.72。旨在对该园建设、管理等项决策提供科学依据。 相似文献
23.
A field experiment was conducted during the winter seasons of 1992–93 and 1993–94 at Anand to study the effect of FYM, nitrogen and source of fertilizer on growth and yield of mustard [ Brassica juncea (L.) Czernj & Cosson]. The results showed significant variation in leaf area index (LAI), crop growth rate (CGR), dry matter production and seed yield. The direct effect of farmyard manure (FYM) was conspicuous in improving the growth of mustard. FYM application at 10 tonnes ha−1 significantly increased the LAI, CGR and dry matter accumulation per plant at almost all the stages during first year study (1992–93) and in pooled analysis. Similarly, nitrogen application registered maximum LAI, CGR at 75 kg level and RGR and NAR at 50 kg level at almost all the during both years. Sulphur carrying source (Ammonium sulphate plus single super phosphate) increased all stages growth characters. Maximum dry matter accumulation per plant and seed yield were recorded with highest levels of FYM (20 tonnes ha−1 ), N (75 kg ha−1 ) and source having S. Seed yield was strongly associated with LAI and dry matter accumulation per plant at all the stages. 相似文献
24.
Field experiments were conducted at Tamil Nadu Rice Research Institute, Aduthurai, India, during the wet seasons of 1992 and 1993 to study the effect of full and partial substitution of fertiliser N with green manure N (Sesbania rostrata) on nitrogen uptake, yield attributes and yield of rice. The experiment consisted of eight treatments with two levels of N (100 and 200 kg ha−1 ) and three sources of N application viz., fertilizer, integrated (1:1 fertilizer and green manure N) and green manure N compared to the recommended practice (150 kg fertilizer plus 6.25 t ha−1 (72 kg N) green manure) and a no N control. Nitrogen application markedly increased the N uptake. Combined use of the two N sources at 200 and 222 kg N ha−1 and of single fertilizer N at 200 kg N ha−1 recorded the maximum N uptake, increased the yield attributes such as number of panicles per unit area, weight per panicle, number of total and filled grains per panicle and test weight. At 200 kg N ha−1 full substitution of N by green manure reduced the grain yield but only partial substitution of N by green manure resulted in almost similar yield as single fertilizer N. Thus 200 kg N ha−1 applied in equal proportions of fertilizer and green manure N can be recommended for medium duration rice cultivars. 相似文献
25.
本文主要通过应用统计学的有关知识,提出适应南方集体林区木材市场开放新格局的一种估测林木资源消耗量的方法;并将这种方法在沙县进行了实地验证;分析了其可靠程度与经济意义。 相似文献
26.
低蛋白质氨基酸平衡饲粮对早期断奶仔猪腹泻和生产性能的影响 总被引:8,自引:2,他引:6
《中国畜牧杂志》1995,(4):11-13
本研究选用18头28±1日龄断奶的杂交仔猪(平均体重约5.5kg),研究低蛋白质氨基酸平衡饲粮对早期断奶仔猪腹泻和生产性能的影响。试验结果显示:(1)低蛋白质氨基酸平衡饲粮使仔猪血浆挥发性盐基氨含量、血浆尿素氨含量和腹泻指数降低(P<0.05或0.01)。(2)采食全植物蛋白型氨基酸平衡饲粮(CP18.3%)的仔猪,其平均日增重(ADG)、平均日采食量(ADFI)和料肉比(P/G)与采食复合蛋白型对照饲粮(CP19.7%)的仔猪差异不显著(P>0.05),但前者的增重成本比后者降低(P<0.05)31%。(3)采食复合蛋白型氨基酸平衡饲粮(CP18.4%)的仔猪的生产性能优于采食复合蛋白型对照饲粮(CP19.7%)的仔猪,前者的ADG和ADFI分别提高(P<0.05)61%和32%,F/G和增重成本分别下降(P<0.05)24%和37%。(4)采食全植物蛋白型氨基酸平衡饲粮的仔猪,其ADG和ADFI低于(P<0.01)采食复合蛋白型氨基酸平衡饲粮的仔猪。前者的F/G和增重成本趋于高于后者,但差异不显著(P>0.05)。以上结果表明,低蛋白质氨基酸平衡饲粮可显著降低仔猪断奶后腹泻和提高仔猪生产性能。复合蛋白型? 相似文献
27.
K-S. Dai C-S. Liang Y. T. Ch'iu P-C. Yang I. C. Cheng 《Veterinary research communications》1995,19(2):115-125
The purpose of this study was to determine whether myocardial adenosine triphosphatase (ATPase) activities were reduced in pigs with naturally occurring hypertrophic cardiomyopathy (HCM). The selection of hearts for the HCM and the normal control groups depended on histological examination. Specific ATPase activity and 5-nucleotidase activity were measured in left ventricular myocardium obtained from HCM (n=7) and normal control (n=7) animals. The histological features of HCM included marked disorientation of muscle cells, thickening of the intramural coronary arterial wall with a narrowed lumen, endocardial fibrosis and myocardial fibrosis. The HCM group showed significant increases in both heart weight (32%) and heart weight to body weight ratio (46%). The total ATPase activity in crude homogenates from the HCM group was significantly decreased by 16%. Azide-sensitive ATPase (mitochondrial ATPase) activity, ouabain-sensitive ATPase (Na+,K+-ATPase) activity, basal Mg2+-ATPase activity and Ca2+-ATPase activity were all significantly decreased by 18%, 30%, 20% and 50%, respectively. In contrast, no significant decrease was found in the mean values for 5-nucleotidase activity. These results suggest that myocardial ATPase activities are suppressed in pigs with naturally occurring HCMAbbreviations ATP
adenosine triphosphate
- gww
grams wet weight
- HCM
hypertrophic cardiomyopathy
- Pi
inorganic phosphate 相似文献
28.
P. Gustin B. Urbain A. Delaunois K. Zeimes M. Ansay 《Veterinary research communications》1992,16(1):69-82
The right and left lungs of 5 healthy Minipigs and of 13 healthy Landrace piglets were isolated, perfused at constant pressure and maintained in an isogravimetric state under zone III conditions (pulmonary venous pressure>alveolar pressure). By applying the double, arterial and venous, occlusion technique, the total blood flow resistance (R
t) was partitioned into four components: arterial (R
a), pre-(R
a) and post-capillary (R
v) and venous (R
v). The capillary filtration coefficient (K
f,c) was evaluated by measuring the weight gained by the lungs when the arterial and venous pressures were suddenly increased. In the youngest Landrace piglets (5 weeks old), there was an uncontrolled vasoconstriction which sometimes prevented perfusion of the lungs and induced a large increase inR
t. These high values ofR
t were decreased by tolazoline administration. The values ofR
t recorded in older pigs (12–13 weeks old) were lower in Minipigs (33.66±3.77 cmH2O min L–1 per 100 g of lungs;n=5) than in Landrace piglets (55.20±6.18 cmH2O min L–1 per 100 g;n=5). This breed difference was due to the differences inR
a andR
v. The mean values ofK
f,c were 0.193±0.015 and 0.202±0.029 ml min (cmH2O)–1 per 100 g of the lungs in Minipigs and Landrace piglets respectively. All these parameters were stable for the 3 hours following the equilibrium period. It was concluded that: (1) There is an age-related maturation of the control of the vasomotor tone in porcine lungs. (2) Pulmonary microvascular haemodynamics are influenced by the breed of the pigs. (3) There was no difference in theK
f,c values between both the breeds. (4) A comparison of the values reported for dogs and rabbits with our data shows that the pre- and post-capillary resistances and, to a lesser extent, the arterial and venous resistances are relatively high in pigs. 相似文献
29.
本文通过理论分析与试验研究了屋顶遮阳系统在猪舍夏季降温中的应用效果,应用红外热图像摄取及分析系统获取猪舍屋顶内表面和猪体表面的热图像,结果表明屋顶上架设铝箔遮阳网对减少太阳辐射进入猪舍进而降低猪舍环境温度和减轻猪热应激的效果显著。 相似文献
30.
通过对哺乳仔猪群、保育群、育成群各月死亡率的统计分析发现,冬季低温对哺乳仔猪群、保育群死亡率的影响远远大于夏季高温的影响。冬季低温对保育群的死亡率影响最大,而对育成群几乎没有影响。夏季高温对不同猪群的死亡率有不同程度的影响力。不同猪群对温度反应的快慢、强度及持续期各不相同。 相似文献