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1.
Fresh applications of phosphorus (P) may cause ‘incidental’ losses of dissolved and particulate P forms in land runoff when rainfall interacts directly with fertilizers and manures which are spread, or excreted, onto the soil surface. Research indicates that when incidental P losses (IPL) occur, they often make the dominant (50–98 %) contribution to measured P loads in surface and sub‐surface runoff from field plots, with increased risk of eutrophication where P‐enriched runoff is routed directly to the watercourse. Rates of P loss are temporally and spatially very variable (< 1 to 25 % of total P applied) depending on the amount of P applied; the P release properties of the materials applied (% P extractable in water), the timing of storm events after application and the amounts of runoff generated. Large P applications left on the surface of wet, frozen, compacted, and intensively underdrained soils in high rainfall areas are particularly vulnerable to IPL. Concentrations of P in runoff are often greatest during the first storm event following P application, but can remain high for several weeks, or even months after application. Catchment scale impacts are more difficult to quantify due to the effects of dilution with runoff from fields without IPL, and the contributions of P from other sources. Approaches to predicting IPL are discussed and need to be improved in order to assess the contribution of IPL to catchment P loads in river basin management planning. Strategies to control IPL should focus on adoption of more sensitive management practices in fields with a high risk of rapid runoff or preferential flow, and are likely to very effective.  相似文献   
2.
Abstract: An 18-month-old male Doberman Pinscher was referred to the Veterinary Medical Teaching Hospital of the College of Veterinary Medicine for an erythemic nodular mass on the right forelimb. The mass was diagnosed as cutaneous lymphoma, based on cytologic examination of a mass aspirate and histopathology. Using immunohistochemistry the neoplastic cells were positive for CD3 but negative for CD79a, E-cadherin, and pancytokeratin, confirming their origin as T lymphocytes. No tumor recurrence was noted 18 months after surgery. To our knowledge, this is the first report of a solitary nodular form of cutaneous lymphoma in a young dog.  相似文献   
3.
Long-term data are given on priority directions in apple breeding: for an increased content of biologically active substances in fruit and for scab resistance. The high effectiveness of apple breeding at the polyploid level is shown.  相似文献   
4.
Betaine is found ubiquitously in plants, animals, microorganisms, and rich dietary sources including seafood, spinach, and wheat bran. The chief physiological role of betaine is to function as a methyl donor and an osmolyte. Betaine also acts as an osmolyte, to maintain the avian’s cellular water and ion balance to improve the avian’s capacity against heat stress via preventing dehydration and osmotic inactivation. It helps in maintaining the protective osmolytic activity, especially in heat-stressed birds. Betaine may promote various intestinal microbes against osmotic variations and thus improve microbial fermentation activity. Previous studies showed that dietary supplementation of betaine in poultry diets could positively affect nutrients’ digestibility, reduce abdominal fat weight, and increase breast meat yield. In addition, betaine has been reported to protect internal organs and boost their performance. Its inclusion in poultry diet is sparing essential amino acids like choline and methionine. In addition, it may play an important role in lean meat production by positively affecting the lipid metabolism with increased fatty acids catabolism and thus reducing carcass fat deposition. The aim of this review article was to broaden the knowledge regarding betaine and its importance in the poultry industry to cope with the heat stress problem. Moreover, it should be added to the diet as a natural anti-stressor through different routes (water/feed) to overcome the heat stress problem. However, further studies need to be conducted at the genetic and molecular basis to elucidate the mechanism behind the betaine as a natural anti-heat agent to decrease the heat stress problem in the poultry industry.  相似文献   
5.
The radiosensitivity of uredospores of the stem rust pathogen is studied in a wide range of β- and γ-radiations (14–2500 Gy). It is shown that a change in the degree of infection of plants is related not to loss of virulence of the pathogen but to their genetically determined resistance. The biochemical indices of wheat resistance to the pathogen are determined.  相似文献   
6.
Journal of Crop Science and Biotechnology - India has a diverse range of agro-ecological conditions which support the cultivation of different rice varieties differing in the adaptation which is so...  相似文献   
7.
Buffalo is considered short-day breeder in tropical and subtropical part of the world and seasonality and photoperiodism impart major influence on its fertility. However, its impact on in vitro embryo production (IVEP) remains elusive. Therefore, this study investigated the effect of seasonal variations and photoperiodism on morphological and molecular parameters of IVEP in buffalo. For this purpose, we conducted two different experiments on the oocytes obtained by aspirating follicles from abattoir derived ovaries. In Exp. I, retrospective analysis was performed for oocyte recovery, blastocyst and hatching rate, during four consecutive seasonal periods (i.e. January–March, April–June, July–September and October–December). In Exp. II, oocytes from peak breeding and non-breeding seasons were subjected to 24 hr in vitro maturation and evaluated for polar body extrusion to assess maturation rate. Results showed that embryo development was markedly low during second quarter (April–June) and maximum during fourth quarter (October–December) of the year; referred as non-breeding and breeding seasons, respectively. Comparative data analysis demonstrated that poor oocyte quality is major reason for lesser efficiency of embryo production during non-breeding season than peak breeding season as suggested by poor oocyte recovery (2.31 ± 0.10 vs. 3.65 ± 0.27) and maturation rate (33.32 ± 2.1 vs. 63.15 ± 7.31). Subsequently, comparative gene expression analysis of blastocysts during peak breeding season significantly upregulated pluripotency gene (OCT-4) and downregulated heat shock protein 90, as compared to non-breeding season. Therefore, it could be divulged from the present study that seasonal variations and photoperiodism have profound effect on oocyte quality and subsequent embryo development. It is recommended to find suitable additives for in vitro maturation that could mitigate seasonal effects.  相似文献   
8.
ABSTRACT

The present investigation was based on the hypothesis that the endophytes residing in the roots of halophytes have better adaptation to saline conditions. Six halophytic herbs were collected from Khewra salt range (EC = 4.7 dS m?1 and SAR = 25.7). From these herbs, root pieces of Cenchrus ciliaris were shade dried; finely ground to powder and three plant growth promoting rhizobacteria (PGPR), Bacillus cereus, Pseudomonad moraviensis, and Stenotrophomonas maltophilia, were isolated. Root powder in sterilized and unsterilized forms was added in the saline-sodic field on wheat and mixed with soil in pot experiment with induced NaCl (150 mM). Sterilized root powder increased organic matter NO3-N and P contents of soil and leaves, fresh weight, sugar content, and yield attributes. The root powder application in unsterilized form significantly decreased EC, SAR, and Na content of field soil with concomitant increase in soil and leaves K, P, and NO3-N. The farmer’s benefit was increased by 33% at yield. Root powder-induced salt tolerance was mediated by the PGPR (residing inside the root) through increased growth and better physiological adaptations. It is inferred that root powder harboring the PGPR may be an alternative to biofertilizer with longer shelf life and may also serve as carrier for the preparation of effective biofertilizer for saline land using other PGPR bio-inoculants.  相似文献   
9.
Protein kinase A, a cyclic adenosine monophosphate (AMP)‐dependent enzyme, normally exists within mammalian cells; however, in cancer cells, it can leak out and be found in the serum. Extracellular cyclic AMP‐dependent protein kinase A (ECPKA) has been determined to increase in the serum of cancer‐bearing dogs. However, there have been no reports in the veterinary literature on serum ECPKA autoantibody (ECPKA‐Ab) expression in dogs with cancer. The aim of this study was to evaluate ECPKA‐Ab and C‐reactive protein (CRP) as serum biomarkers for cancer in dogs. ECPKA‐Ab and CRP levels were detected by an enzyme‐linked immunosorbent assay in serum samples from dogs with malignant tumours (n = 167), benign tumours (n = 42), or non‐tumour disease (n = 155) and from healthy control dogs (n = 123). ECPKA‐Ab and CRP levels were significantly higher in the dogs with malignant tumours than in those with benign tumours or non‐tumour diseases, as well as in the healthy controls (P < 0.001, Kruskal‐Wallis test). There was a significant positive correlation between the neoplastic index, which was developed using ECPKA‐Ab and CRP levels, and the presence of cancer in dogs (P < 0.001); the area under the receiver‐operating characteristic curve was estimated to be >0.85 (P < 0.001). In conclusion, ECPKA‐Ab is a potential serum biomarker for a broad spectrum of cancers. Combined measurement of CRP and ECPKA‐Ab levels in serum improves the sensitivity and accuracy of a diagnosis of cancer in dogs.  相似文献   
10.
This study aimed to investigate the effects of different concentrations of 1,2‐bis‐(o‐aminophenoxy)‐ethane‐N,N,N0 N0‐tetraacetic acid, tetra‐acetoxymethyl ester (BAPTA‐AM), an intracellular calcium chelating agent, on stallion semen cooling and freezing–thawing. After collection, semen was extended (1:1 v/v) on a skim milk‐based extender, centrifuged and resuspended at 400 million/ml into cooling or freezing extenders containing 0, 5, 25, 50, 100 and 200 μΜ BAPTA‐AM. Motility parameters were assessed after cooling in Equitainer at 5°C for 12, 24, 48, 72 and 120 hr and after freezing–thawing. In addition, mitochondrial membrane potential, intracellular ATP, reactive oxygen species and malondialdehyde concentrations were measured in cryopreserved‐thawed semen. Cooled stored (48 hr) semen containing 50 μΜ BAPTA‐AM and control extender (0 μΜ BAPTA‐AM) was used to assess fertility. Inclusion of 50 μΜ BAPTA‐AM resulted in superior sperm motility parameters during cooled storage when compared to other groups (< 0.05). Furthermore, semen cryopreserved in extender containing 50 μΜ BAPTA‐AM showed increased intracellular ATP and mitochondrial membrane potential, whereas reactive oxygen species and malondialdehyde were increased after thawing for all groups (< 0.05). Addition of 50 μΜ BAPTA‐AM to cooling extender resulted in similar pregnancy rates to the control group (75% vs. 73.6%, respectively; > 0.05). In conclusion, the addition of BAPTA‐AM to semen extenders aided stallion semen cryopreservation in a dose‐dependent manner. Furthermore, the cooling extender supplemented with 50 μΜ BAPTA‐AM could be used to prolong the sperm motility during cooling without apparently compromising fertility. Field trials should be conducted to assess fertility of cryopreserved stallion semen with BAPTA‐AM.  相似文献   
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