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91.
为解决平菇栽培原料供应价格飙升、供应紧张的现状,以平菇为试材,在平菇栽培培养料中按不同比例添加葡萄枝屑(0、30%、50%、70%),研究葡萄枝屑对平菇菌丝体生长、子实体产量及子实体营养成分的影响。先将葡萄枝屑、玉米芯、土霉素药渣等原料按不同比例浸泡混匀,装袋培养灰色平菇栽培种,采用柱前衍生反相高效液相色谱法测定平菇子实体氨基酸含量,按照国家标准测定方法测定平菇中微量元素含量。结果表明:添加适宜比例葡萄枝屑栽培平菇,菌丝体长势强,生长速率高,菌丝洁白、粗壮、紧密;添加葡萄枝屑可显著提高平菇产量,其中以添加50%葡萄枝屑的平菇产量最高(324.0 g/袋),且加入葡萄枝屑3个处理的生物学效率为90.3%~99.7%;添加葡萄枝屑可提高平菇子实体中铁、锌、硼等微量元素的含量;4个基质配方栽培的平菇基本能满足人体对必需氨基酸的搭配需求,且添加葡萄枝屑栽培的平菇赖氨酸含量显著高于不添加葡萄枝屑的对照。因此,加入葡萄枝屑可提高平菇的产量及微量元素含量,满足人体对必需氨基酸的需求。  相似文献   
92.
A total of 120-day-old broilers were divided into four groups. In group-A, broilers were left without supplementation of minerals and vitamins (control), while the broilers in groups B, C and D were given mineral and vitamin supplementation 1-6, 1-4 and 5-6 weeks, respectively. The results showed that the feed consumption of broilers in groups A, B, C and D was 4 234.61, 4 028.38, 4 169.32 and 4 181.87 g ? b-1; water intake was 9 668.88, 9 295.55, 9 882.11 and 9 402.86 L ? b-1; live body weight was 2 068.90, 2 360.90, 2 255.30 and 2 157.40 g ? b-1, respectively. The feed conversion ratio of broilers in groups A, B, C, D was 2.05, 1.71, 1.85 and 1.94 g ? b-1, carcass weight (wt) was 1 550, 1 656, 1 552 and 1 528.8 g ? b-1, and average dressing percentage was 61.24, 63.02, 62.60 and 60.51 respectively. Weight of heart in groups A, B, C and D was 15.13, 13.16, 11.72 and 11.50 g ? b-1, weight of gizzard was 32.98, 37.48, 37.62 and 33.35 g ? b-1, weight of liver was 51.94, 48.70, 51.94 and 48.70 g ? b-1and spleen weight was 3.48, 3.28, 3.06 and 2.82 g ? b-1, respectively. Average mortality of broilers in groups A, B, C and D was 6, 2, 4 and 5 resulting 20.00%, 8.00%, 13.00% and 16.00% mortality rate, respectively. The haemoglobin level in blood of broilers in groups A, B, C and D was 9.20, 12.23, 10.87 and 7.60 g ? dL-1, white blood cell level 77.47, 89.83, 81.63 and 78.13 (×106μL); red blood cell level 1.85, 2.58, 2.45 and 1.40 (×106μL), respectively. It was concluded that broilers given mineral and vitamin supplementation (Aquavit Electrolyte) for 6 weeks were proven to be most effective regime to result the lowest feed intake, the highest live body weight, better feed conversion ratio, higher carcass weight, better dressing percentage, higher net profit, relatively improved haemoglobin level in blood, increased counts of red blood cells and white blood cells. In all the above parameters, the broilers received mineral and vitamin supplementation for the first 4 weeks and the last 2 weeks showed relatively inferior performance, it is suggested that mineral and vitamin supplementation through water for partial period was not much effective in broiler productivity. Broilers may be supplemented with commercially available minerals and vitamins in drinking water over full rearing period, for achieving higher live body weight and efficient feed conversion ratio.  相似文献   
93.
Soil salinity is a serious abiotic factor affecting the production of crops by reducing potassium (K) uptake due to strong competition with sodium (Na) cations in the root regions. In calcareous soils, most of the nutrients precipitate in unavailable forms for plants. This study investigated the physiological and biochemical response of two wheat genotypes salt tolerant Abadghar and salt sensitive Pari-73 supplemented with K and zinc (Zn) nutrition. A factorial experiment with three levels of K (0, 50 and 100 kg ha?1) and three levels of Zn (0, 25 and 50 kg ha?1) based on a complete randomized design was employed. The results showed significant effect of treatments on chlorophyll (Chl) contents, water relations, nitrogen metabolism and yield attributes. The treatment K+Zn (100, 25 kg ha?1) was the most effective in increasing grain yield. The results achieved highlight the importance of K and Zn nutrition in salt-stress conditions.  相似文献   
94.
Characterization of fecundity genes offers the opportunity to improve production efficiency, and the consequent increase in litter size in livestock industry, through utilizing them in breeding programs. The main objective of this study was to detect the BMPR‐IB, BMP15 and GDF9 gene mutations and to investigate whether these mutations are associated with litter size in Egyptian sheep breeds. To achieve this goal, 73 adult ewes representing Barki (n = 33) and Rahmani (n = 40) breeds were used. Polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) screening approach was used to detect the presence of FecB, FecXG and FecXI mutations in the two selected breeds. Results of this study showed that the three different candidate gene mutations, namely FecB, FecXG and FecXI are not present among these selected populations of the Egyptian breeds. Further studies regarding other mutations and/or other genes, which may influence ovulation rate, should be carried out to determine the type and mode of inheritance of such genes in Egyptian sheep breeds.  相似文献   
95.
To address nitrogen (N)-related environmental pollution, development of an economical, slow-release urea fertilizer is the need of the hour. A study was conducted on the reduction of nitrogen released from granular urea fertilizer by applying sulfur, gypsum, bentonite, and starch as coating material. Paraffin wax was used as a binder. The dissolution rates were studied by changing the composition of coating mixture using high-performance liquid chromatography. SEM was used to study the morphology of coated urea in terms of smoothness and uniformity. The ultraviolet spectroscopy analysis further authenticated the release behavior of coated urea in terms of nitrogen concentration. Coating material reduced the release rate of nitrogen from urea fertilizer, significantly. Mixture of sulfur and gypsum coating on urea gave slowest release rate of nitrogen from urea fertilizer, i.e., 37%, as compared to uncoated urea and thus seems to be the most promising binding material for product development.  相似文献   
96.
Summary Stereological procedures were used to estimate the amount of amyloid deposition in the pancreatic islets of 83 cats from random sources in south-eastern Queensland. Most had only minor deposits of less than 20% of islet volume (median 9%), but deposits equal to more than 50% of the islet volume were found in 10% of the cats. Amyloid deposition in pancreatic islets was correlated with the age of the cat. Although similar observations have been made previously in cats from the USA, the frequency of amyloid deposition was higher in this population of cats from south-eastern Queensland.  相似文献   
97.
Various dog breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of these characteristics are under genetic control. However, little is known about genes related to behavioral traits in canine species. In humans, it has been reported that the dopamine receptor D4 gene (DRD4) includes polymorphism at several regions that relate to personality or psychiatric disorders. In an earlier study by the authors of the present study, the polymorphisms in canine DRD4 exon III and exon I regions were reported. In the present study, a novel polymorphism in canine DRD4 intron II was found based on a 17 base pair insertion/deletion, and the two alleles detected were named P (shorter allele) and Q (longer allele). The allelic distribution in 28 breeds of dog, including a total of 1114 unrelated individuals, were then investigated. Both P and Q alleles were detected in most of the breeds investigated; however, the frequencies of P and Q differed greatly between breeds. With respect to classification based on breed origin, P and Q alleles were frequent in Occidental and Oriental breeds, respectively. Furthermore, two subspecies of wolves, the ancestors of dogs, were analyzed for the comparison of allele frequencies with dogs, and the P allele was predominant in both European and Chinese wolves.  相似文献   
98.
Zafar S  Ahmad MA  Siddiqui TA 《Fitoterapia》2002,73(7-8):553-556
The aqueous extract of Delphinium denudatum (Dd) roots showed a significant effect against morphine- (10 mg/kg) induced tolerance and dependence in mice. Oral administration of the extract (200-1600 mg/kg) showed a significant dose-dependent inhibition of naloxone- (1 mg/kg) induced withdrawal.  相似文献   
99.
100.
运用层次分析法和模糊数学综合评判方法,根据石河子、昌吉、吐鲁番等8个地区的无霜期、温度、积温和降水因素,建立了数学模型,并对新疆天然甜型葡萄酒原料种植区域进行了区划研究.结果表明:吐鲁番的综合评价最高,其次为和田,评价值分别为0.97和0.91,属非常适宜种植区;哈密和喀什的评价值分别为0.81和0.87,属适宜种植区;库尔勒的为0.71,属次适宜种植区,而石河子、昌吉和霍城的评价值均小于0.59,属不适宜种植区.  相似文献   
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