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721.
The equine leukocyte cell lines, namely eCAS (bone marrow derived) and EqT8888 (lymphoma derived) were used for further analysis, using 40 commercially available mAbs that showed reactivity with equine PBMC. Most mAbs that were detected in these previous studies to react with PBMC, however, did not react with either of these cell lines. Fifteen mAbs were positive on at least one of the cell lines and indicate opportunities to set up further tests using these cells. Notably, two mAbs directed against human CD34 were detected to react with eCAS.  相似文献   
722.
Grassland primary productivity is the function that underpins the majority of the fodder production in cattle-rearing silvopastoral farms. Hence, understanding the factors that determine grassland productivity is critical for the design and management of silvpastoral systems. We studied the effect of two factors with documented impact on grassland productivity in seasonally dry silvopastures of Nicaragua, rainfall and trees. We assessed the effects of three species that differed in crown size and phenology, one evergreen, Cassia grandis, and two deciduous species, Guazuma ulmifolia and Tabebuia rosea. Overall, grassland ANPP had a quadratic response to rainfall, with a decline at high rainfall that coincided with peak standing biomass and grassland cover. Trees had a predominately negative effect on grassland productivity, and the effect was concentrated in the rainy season at peak productivity. The effect of the trees corresponded with the tree crown area, but not with crown density. Trees reduced the standing biomass of graminoids and increased forb biomass; thus, the effect of trees on grassland ANPP appears in part to respond to changes in grassland composition. We also found higher levels of soil moisture content below the tree canopy, particularly at the peak of the rainy season when soils tend to become waterlogged. The evergreen species, C. grandis, affected grassland ANPP more strongly than the deciduous species.  相似文献   
723.
Herbal products have been in use for many years, but they are becoming more and more popular in recent years, and they are currently in widespread use throughout the world. In this review article we describe the histopathologic findings found after exposure to 12 dietary herbals in studies conducted in rodent model systems. Clear or some evidence for carcinogenic activity was seen with 6 herbals, with the liver being the most common organ affected. The intestine was affected by two herbals (aloe vera nondecolorized extract and senna), three had no clear evidence for carcinogenic activity and one was cardiotoxic (Ephedrine and Ephedra in combination with caffeine). Information from these studies can help to better understand potential target organs for further evaluation from exposure to various herbal products.  相似文献   
724.
An experiment was conducted from December 2003 to April 2004 to observe the over‐wintering growth of freshwater prawn, Macrobrachium rosenbergii, with catla, Catla catla and rohu, Labeo rohita in polyculture using formulated diets. The study was conducted in eight experimental ponds, each 80 m2. Three experimental diets containing 30% protein were prepared using fish meal, meat and bone meal, mustard oilcake, rice bran, wheat bran and molasses (binder), and assigned to treatments T1, T2 and T3 respectively. A commercial diet from Saudi‐Bangla Fish Feed was assigned to T4 (reference diet). Each treatment had two replicate ponds. Juvenile prawns and catla and rohu fingerlings (initial weight 1.60±0.10, 30.0±1.2 and 25.0±1.1 g respectively) were stocked at a ratio of 2:1:1 (prawn:catla:rohu). A total of 160 prawn and fish (20 000 ha?1) were stocked in each pond. Fish were fed twice daily at 3% body weight (b.w.) for the first 3 months and 5% b.w. for the last 2 months. Prawns in T1 fed diet 1 had significantly higher (P<0.05) weight gain compared with that of T3. The reference group and T2 had intermediate values not significantly different from either. Weight gains of catla and rohu were significantly higher in T1. The feed conversion ratio values of different diets ranged between 1.89 and 2.13. Survival (%) ranged from 90.0% to 95.0% for catla, 87.5% to 92.5% for rohu and 70.0% to 76.3% for M. rosenbergii, and there were no significant differences (P>0.05) among different treatments. Total production ranged between 2196 and 2679 kg ha?1, with T1 showing significantly higher production and net profit (taka 56 531.9 ha?1). The results of the study demonstrated that it is possible to culture M. rosenbergii with carp in polyculture during the winter utilizing the late‐produced PLs. Further study is needed to determine the optimum stocking density of M. rosenbergii in carp polyculture.  相似文献   
725.
An assessment of the nutritive value of palm kernel meal (PKM) and aflatoxin‐contaminated PKM (obtained by fermenting PKM with Aspergillus flavus) as a dietary ingredient in pelleted feed for tilapia, Oreochromis mossambicus Peters, was carried out in a 12‐week feeding trial. Seven isonitrogenous (40% crude protein) and isoenergetic (15.1 kJ g?1) practical diets were formulated and fed close to apparent satiation to triplicate groups of 12 fish (mean initial weight 8.4 ± 0.1 g). The control diet contained 30% fish meal and 10% soybean meal (SBM) proteins. Four other experimental diets containing 20% and 50% of the SBM protein replaced by either PKM or fermented PKM, respectively, were formulated. Two additional diets containing either PKM or fermented PKM supplemented with a commercial aflatoxin adsorber (0.5% SorbatoxTM) were also formulated. Measured aflatoxin B1 levels in the fermented PKM‐based diets ranged from 75 to 100 µg kg?1 diet. The growth performance and feed utilization efficiency of tilapia fed fermented PKM‐based diets were significantly lower than in fish fed the control diet at all inclusion levels (P < 0.05). Despite a small reduction, weight gains of tilapia fed PKM‐based diets were not significantly different compared with fish fed the control diet. The addition of 0.5% Sorbatox did not produce any beneficial or negative effects to the growth of tilapia. Under the dietary conditions of the present experiment, it was concluded that PKM can substitute up to 50% SBM in practical diets for O. mossambicus without much adverse effect to fish growth. However, when PKM was contaminated with A. flavus, its' incorporation into tilapia diets resulted in growth depression as a result of decreased diet digestibility and also possibly because of the presence of anti‐nutrients found in the contaminated PKM.  相似文献   
726.
727.
Insulin-like growth factor 2 (IGF2) plays an important role in muscle growth and it might be used as a marker for the growth traits selection strategies in farm animals. The objectives of this study were to detect polymorphisms in exon 10 of IGF2 and to determine associations between these polymorphisms and growth traits in Egyptian water buffalo. PCR-single-strand conformation polymorphism (SSCP) and DNA sequencing methods were used to detect any prospective polymorphism. A novel single nucleotide polymorphism (SNP), C287A, was detected. It was a non-synonymous mutation and led to replacement of glutamine (Q) amino acid (aa) by histidine (H) aa. Three different SSCP patterns were observed: AA, AC, and CC, with frequencies of 0.540, 0.325, and 0.135, respectively. Association analyses revealed that the AA individuals had a higher average daily gain (ADG) than other individuals (CC and AC) from birth to 9 months of age. We conclude that the AA genotype in C287A SNP in the exon 10 of the IGF2 gene is associated with the ADG during the age from birth to 9 months and could be used as a potential genetic marker for selection of growth traits in Egyptian buffalo.  相似文献   
728.
Internationally there is a gradual decline in availability of fresh water to be used for irrigation. As a consequence, the use of drain water for irrigating agricultural lands is on the rise particularly in urban areas of developing countries especially Egypt. On the other hand, there is increasing concern regarding the exceedance of statutory and advisory food standards for trace metals throughout the world. A study was undertaken to assess the long-term effect of irrigation with drain water on heavy metal content in soils and diversity of terricolous biota. An agroecosystem in Bahr El-Baqar area, south of Port Said, Egypt were selected where various cereals, vegetable and fodder crops have successfully been grown. During the period from September (2004) to February (2005), 25 soil profiles, 100 soil and 30 water samples were collected from cultivated soil and drain of Bahr El-Baqar. Soil heavy metals content (Zn, Pb, Cd, Co, Mn and Cu), gypsum, organic matter, total calcium carbonates, cations, anions, electric conductivity and pH were determined. Water samples has been subjected to various analyses including water temperature, pH, total soluble salts, electric conductivity, total nitrogen, total phosphate, heavy metals and organic loads (chemical oxygen demand and biological oxygen demand). For isolation and examination of total mycobiota, arbuscular-mycorrhizal fungi (AMF) and nematodes from rhizosphere soils, samples were collected from dominant plant species in the study area. Obtained data were subjected to multivariate analysis by using Canonical Correspondence Analysis to find out the relationship between biota and environmental variables. Results indicated that concentrations of heavy metals exceeded the maximum allowable limits while water analyses showed that organic load values are slightly increase in all examined samples and samples were not complying with the standard value given by law 48/1982 for ambient water quality in the drain. It was possible to encounter as many as 43 fungal species belonged to twenty-one genera from five sites in the agroecosystem in south Port Said. The results show that Zygomycota represented by six species (7.59% of the total isolate number), teleomorphic Ascomycota (3 species, 3.78%), anamorphic Ascomycota (31 species, 86.96%) and mitosporic fungi (3 species, 1.67%). The AM fungal spores obtained belonged to the three genera namely Acaulospora, Gigaspora, and Glomus and eight species. While family Glomeraceae accommodates the greatest range of species (6 species), the other family Gigasporaceae accommodate the lowest range (two species). Twelve species belonging to eight genera and six families of plant-parasitic nematodes were identified throughout the study. Total levels of heavy metals showed a trend relationship between metal concentration in soil and long term of irrigation assuming that there is a continuous deposition of heavy metals on the soils due the continuous use of Bahr El-Baqar drain in watering soil for many years in which both living and non-living components of ecosystem are hazardly affected. Detailed studies to minimize the quantity and improve the quality of wastewater discharged should be carried out for each industry. Research must take the objective of sustainability into consideration. Legislation sensible to environmental control should depend on a thorough knowledge of the existing situation and careful assessment of its likely impact on the development. On the other hand activation of law 4/1994, for the protection of environment in Egypt, is urgently needed.  相似文献   
729.
Ovalbumin (OVA) was phosphorylated by dry-heating in the presence of pyrophosphate at pH 4.0 and 85 degrees C for 1 and 5 days, and the physicochemical and structural properties of phosphorylated OVA were investigated. The phosphorus content of OVA increased to 1.01% by phosphorylation, and the electrophoretic mobility of PP-OVA also increased. Although the solubility of dry-heated OVA decreased, the decrease was slightly depressed by phosphorylation. The circular dichroism spectra showed that the change of the secondary structure in the OVA molecule, as measured by alpha-helix content, was mild by phosphorylation. The exchange reaction between the sulfhydryl and disulfide groups was enhanced and the surface hydrophobicity of OVA increased by phosphorylation. The tryptophan fluorescence intensity of OVA decreased by phosphorylation, suggesting that the conformational change occurred in the OVA molecule by phosphorylation. Although the differential scanning calorimetry thermograms of OVA showed a lowering of the denaturation temperature from 78.3 to 70.1 degrees C by phosphorylation, the stability of OVA against heat-induced insolubility at pH 7.0 was improved. The results indicated molten (partially unfolded) conformations of OVA formed by dry-heating in the presence of pyrophosphate.  相似文献   
730.
DNA isolation from plants is sometimes difficult due to the existence of high levels of endogenous phenolics, polysaccharides, or other substances that may interfere with DNA extraction. Theobroma cacao produces high levels of anthocyanins in young leaves. These plant polyphenols can interfere with DNA isolation. After examination of various procedures for DNA isolation, two commercial isolation procedures have proved to be repeatedly successful using these types of plants, the D(2) BioTechnologies DNA X-tract Plus kit and the Qiagen DNeasy Plant System DNA kit. These commercial kits were chosen for their speed and ease over the CTAB procedure, which is more labor intensive. All protocols assessed yielded DNA suitable for AFLP or SSR procedures. An additional factor in DNA extraction efficiency is the degree of cell breakage, which may be more difficult with the highly fibrous leaf tissue that is found in many monocots, including date palm. Two commercially produced pieces of equipment were tested and, for cacao, both resulted in template DNA yielding amplification product in AFLP or SSR fingerprinting. However, for the fibrous date palm leaf, the larger FastPrep homogenizer consistently yielded DNA that generated higher signals when amplified than did the smaller Disruptor Genie.  相似文献   
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