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61.
Four male buffaloes of 3 to 312 years were subjected to heavy loads during hot dry conditions for 3 h continuously. Rectal temperature, respiration rate and heart rate increased significantly. The blood pH, PO2, increased significantly and PCO2 declined. During work, buffaloes were not able to eliminate heat produced and exhibited such distress symptoms as profuse salivation, frothing, lack of leg co-ordination, excitement and tongue protrusion. The muzzle secretion of buffaloes increased greatly. Even 3 h after discontinuation of work, the physiological reactions had not fully disappeared.  相似文献   
62.
Patchouli oil is one of the most important essential oils used in modern perfumery and cosmetic industries. There is hardly any preparation of oriental nature where patchouli oil is not used. It is used mainly because of fixative property as it gives tenacity to other perfumes. Field experiments were conducted at Bangalore, India, to study the influence of sources and doses of N and K on herbage, oil yield, nutrient uptake, nitrogen utilization efficiency and oil content of patchouli [Pogostemon cablin (Blanco) Benth.]. The results revealed that application of 200 kg N/ha and 41.5 kg K/ha produced significant higher patchouli herbage and oil yields compared with controls. Similarly, N and K uptake were also higher at 200 kg N and 41.5 kg K/(ha year) compared with controls. DCD-coated urea produced higher herbage, oil yield and N uptake and utilization efficiency compared with prilled urea. There was no effect of sources of K on the yield of patchouli. The oil content was not influenced by N, K doses or sources applied. N and K depletion were noticed in the soil.  相似文献   
63.
选择云南省海拔高度76.4m~3200m不同的5个地、县自然发生的肉鸡腹水综合征(ASB)与同品种的健康鸡进行对比研究。结果证实,同品种肉鸡喂同种饲料并在相同的饲养管理条件下,无论在低海拔地区还是高海拔地区发病相同,肉鸡腹水综合征的发生与海拔高低无关。  相似文献   
64.
The clinical signs and gross lesions caused by Eimeria uzura (10(5) oocysts) in Japanese quail (Coturnix coturnix japonica) exhibited little or no influence in the face of intercurrent dietary aflatoxicosis (1 p.p.m. of aflatoxin B1 from Day 0 to 55). Similarly, no significant differences in the mucosal morphology of the intestine were evident histologically between the two groups of Japanese quail. The nervous signs of ataxia, leg weakness, incoordination of movement, torticollis and terminal opisthotonos were toxin-induced manifestations. In the aflatoxic quail, hypoplastic changes and selective depletion of lymphocytes were more prominent in the bursa of fabricius. Increased relative mean weights of liver, kidney, spleen, crop, proventriculus and gizzard were observed in birds due to aflatoxin sensitivity. The combination of E. uzura infection and aflatoxicosis in Japanese quail may cause significant weight loss, and increased oocyst production and reproductive potential.  相似文献   
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磷素环境与马褂木种源的生长和干物质积累   总被引:5,自引:0,他引:5  
自然土壤中有效磷含量很低,难以满足植物最佳生长的需要。据统计,在全世界13·19亿hm2的耕地中约有43%缺磷,而我国耕地则有2/3缺磷(何绪生等,1998)。我国南方地区高温多雨,富铝化作用明显,多数土壤呈酸性或强酸性,磷素固定强烈,土壤有效磷含量仅在1~2mg·kg-1(邱燕等,2003)。虽然施用磷肥的效果显著,但其利用率一般不超过10%,多为土壤固定并转变成植物较难吸收的Ca-P、Fe-P和Al-P等(熊毅,1997)。鉴于植物具有将土壤难溶态磷转化为有效态磷并加以吸收利用的能力,通过选育磷高效利用的植物品种来开发土壤中难溶态的磷素资源,可减小对施用磷…  相似文献   
68.
The crude leaf extracts of Croton cajucara Benth. were studied for their antinociceptive property in chemical and thermal models of nociception in mice. All the tested extracts (hexanic, chloroformic and methanolic), at oral doses of 100 and 200 mg/kg demonstrated significant inhibition of acetic acid-induced writhing and the second phase response of formalin, but did not manifest a significant effect in hot-plate test.  相似文献   
69.
The potential of hedgerow intecrropping with Leucaena leucocephala was explored on vertic Inceptisols over 4 years at ICRISAT Center, Patancheru, India. The study was conducted using a systematic layout involving different alley widths ranging from 1.35 to 4.95 m and with varying distances between hedge and crops. The alleys were cropped with alternate rows of sorghum and pigeonpea. Hedges composed double Leucaena hedgerows 60 cm apart were periodically harvested for fodder. Sole crops of all components and a sorghum/pigeonpea intercrop were included in all four replications of the study.Starting in the second year, Leucaena was progressively more competitive to annual crops, causing substantial yield reduction. Competition (primarily for moisture) was most severe in narrow alleys and was greatest on pigeonpea.The growth of Leucaena was not sufficient to compensate for reduced crop yields. Land equivalent ratios (LERs) calculated on the basis of grain yield of crops and Leucaena fodder yields showed that hedgerow intercropping (HI) was advantageous over sole crops only during the first two years using wide alleys, but disadvantegeous in the last two years. LERs calculated on the basis of total dry matter indicated only a small advantage for HI (13–17 percent) over sole crops in wider (>4 m) alleys. Average returns per year from HI exceeded those of the most productive annual crop system (sorghum/pigeonpea intercropping) by 8 percent in 4.05 m alleys, and by 16 percent in 4.95 m alleys. Fodder production during the dry season was 40 percent of the annual total in these alley widths. Thus hedgerow intercropping at 4–5 m alley width is not very attractive for farmers in semi-arid India, which has 600–700 mm of annual rainfall. There is a need to examine the potential of HI in wider alleys. The merits and limitations of the systematic design are discussed.  相似文献   
70.
Cotton bollworm, Helicoverpa armigera Hubner selected for five generations with Bacillus thuringiensis insecticidal crystal protein Cry1Ac in the laboratory developed 12.98-fold resistance. Resistance and susceptible populations were mass crossed to study the dominance of resistance. The Cry1Ac—selected (BCR) population showed 5.8-fold resistance to Cry1Aa and 5.04-fold resistance to Cry1Ab. The degree of dominance (D) was 0.34 and 0.40 for the R × S and S × R hybrids, respectively, which indicates incomplete recessive character of Cry1Ac resistance in the population. The estimated realized heritability (h 2) and response quotient (Q) of resistance for Cry1Ac were 0.52 and 0.15, respectively. This indicated the lower phenotypic variation in the selected population. The resistance risk assessment based on h 2 indicated that the resistance would increased tenfold after <9 generations for Cry1Ac in the resistant population. The results show the ability of H. armigera to develop resistance against Cry1Ac and cross-resistance to Cry1Aa and Cry1Ab.  相似文献   
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