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61.
Tropical Animal Health and Production - Female fertility in domestic animals in India has exhaustively suffered owing to indiscriminate breeding with single objective of increasing milk production....  相似文献   
62.
This study investigated the occurrence and antimicrobial resistance profiles of Escherichia coli and Salmonella sp. isolated from swine samples submitted to the Minnesota Veterinary Diagnostic Laboratory (MVDL) in Saint Paul, Minnesota from 1995 to 2004. During this time period, a total of 5072 E. coli and 2793 Salmonella sp. was isolated. Most of these isolates were found to be resistant to the tetracycline and beta-lactam group of antibiotics. Resistance to spectinomycin was also frequently observed. An increasing trend in ampicillin resistance and a decreasing trend in apramycin resistance were seen in both pathogens, although ampicillin resistance was relatively higher in E. coli than in Salmonella. Aminoglycoside (amikacin) and quinolone (enrofloxacin) were the only antimicrobials to which minimum or no resistance was observed. The resistance of pig pathogens to several antibiotics indicates the need to routinely monitor the use of these antimicrobials and their associated resistance in pig populations.  相似文献   
63.
Three CMS lines, Ogu1A, Ogu2A and Ogu3A were selected among ten lines after BC7 based on superior commercial, floral and seed setting traits. Introgression of sterile Ogura cytoplasm in cauliflower nuclear background reduced the flower size but did not affect commercial and seed setting traits drastically. Line × Tester analysis was done by taking these three CMS lines free from floral deformities as female parent with nine diverse lines of snowball cauliflower as tester. The parent Ogu2A exhibited highest GCA effect for curd yield (4.51) and harvest index (1.97) while Ogu1A exhibited highest GCA for earliness (−2.73). The parent, Ogu2A exhibited significant GCA for curd length (0.39) while, none of the CMS lines showed significant GCA for curd diameter and depth. Heterosis for curd yield was highest in the hybrid, Ogu2A × Kt-22 (63.5%) followed by Ogu1A × WF (36.9%) and Ogu1A × Kt-15 was the best hybrid for earliness followed by Ogu3A × Kt-22 with heterosis of −14.4% and −11.7%. However, the number of heterotic hybrids for yield and earliness was low indicating narrow genetic base of the snowball cauliflower.  相似文献   
64.
Fourteen apricot genotypes grown under similar cultural practices in Trans-Himalayan Ladakh region were studied to find out the influence of genotype on antioxidant capacity and total phenolic content (TPC) of apricot kernel. The kernels were found to be rich in TPC ranging from 92.2 to 162.1 mg gallic acid equivalent/100 g. The free radical-scavenging activity in terms of inhibitory concentration (IC50) ranged from 43.8 to 123.4 mg/ml and ferric reducing antioxidant potential (FRAP) from 154.1 to 243.6 FeSO4.7H2O μg/ml. A variation of 1–1.7 fold in total phenolic content, 1–2.8 fold in IC50 by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 1–1.6 fold in ferric reducing antioxidant potential among the examined kernels underlines the important role played by genetic background for determining the phenolic content and antioxidant potential of apricot kernel. A positive significant correlation between TPC and FRAP (r = 0.671) was found. No significant correlation was found between TPC and IC50; FRAP and IC50; TPC and physical properties of kernel. Principal component analysis demonstrated that genotypic effect is more pronounced towards TPC and total antioxidant capacity (TAC) content in apricot kernel while the contribution of seed and kernel physical properties are not highly significant.  相似文献   
65.
1. In order to investigate whether emu meat is a potential red meat alternative, this work was carried out with the objective of studying the carcass characteristics, proximate composition, physico-chemical and microbial characteristics and sensory attributes of emu meat.

2. Carcass characteristics clearly indicate that emus are a significant source of lean meat, fat, skin and edible by-products and these findings confirm earlier reports.

3. Proximate composition of emu meat indicated higher protein and ash content and lower fat, total lipids and cholesterol content than meat from other meat animals.

4. The pH, water holding capacity, collagen content and solubility, protein extractability, muscle fibre diameter and Warner–Bratzler shear force values of emu meat are similar to the earlier reports for meats from other food animals.

5. Emu meat is dark, cherry red in colour with significantly higher myoglobin content and the myoglobin is more prone to oxidation as evidenced by higher initial metmyoglobin percentage. The initial thiobarbituric acid reactive substances (TBARS) values and free fatty acids percentage in emu meat were higher than those in meats from other species.

6. Sensory evaluation of cooked emu meat curry revealed highly acceptable scores relative to goat meat curry, the most preferred meat in India.

7. The study shows the potential of emu meat as a new source of low fat, quality meat proteins. However, more studies are required to elucidate the effect of age, sex, muscles, pre-slaughter and post-slaughter factors on different carcass and meat quality characteristics.  相似文献   

66.
Rice planthoppers' damage on Pusa Basmati 1 cultivar was simulated with InfoCrop, a generic crop growth simulation model. The model was calibrated and validated with two experimental data sets on planthopper population and rice yield that were generated through differential insecticide application during the rainy season 2006 and 2007. Simulated yield and total dry matter (TDM) in various treatments over the two experiments were found to be proximal to the observed yields (R2 = 0.972, RMSE = 4.61%) and TDM (R2 = 0.949, RMSE = 3.25%), respectively. Likewise, the simulated yield and TDM losses were also respectively close to observed yield losses (R2 = 0.938, RMSE = 13.53%) and TDM losses (R2 = 0.835, RMSE = 19.12%), suggesting appropriate validation of planthopper damage mechanism on Pusa Basmati 1 rice. Economic injury levels (EILs) of planthoppers were simulated with two control expenditures involving two applications with each of monocrotophos and imidacloprid, and three market prices of Pusa Basamti 1 rice. The EIL exhibited a negative relationship with market value of produce but a positive one with expenditure on control measures. Simulated EILs were comparable to earlier established empirical EILs, indicating utility of simulation models for developing location specific EILs that may help in doing away with the use of blanket EILs. Iso-loss curves, devised through validated model, depicted combinations of crop age and planthopper population that resulted in similar yield losses. Both the EILs and iso-loss curves can be useful in monitoring planthopper populations and promoting judicious pesticide applications that would avoid unwarranted control expenditure and environmental contamination. The simulation models being based on detailed crop ecological and physiological processes and pest damage mechanism can thus aid in development of location-specific decision support tools and ensure precision in pest management decisions.  相似文献   
67.
Simulation models are synonymous with the application of the systems approach in pest management and help to formulate decision support tools for an effective decision-making. A study was undertaken to improve our earlier work on simulation of rice leaf folder (Cnaphalocrocis medinalis) damage and to develop decision support tools for its management. Currently, the leaf folder damage on Pusa Basmati1 rice was simulated with data sets generated in two field experiments during the rainy season 2008 and 2009. Simulated yields and total dry matter in different treatments over the experiments were close to their observed counterparts, indicating an appropriate validation of the leaf folder damage mechanisms on Pusa Basmati1 rice. The leaf folder economic injury levels were simulated based on control expenditure on application of cartap hydrochloride 50SP and quinalphos 25SC, and market price of Pusa Basamti1. The simulated economic injury levels of the leaf folder were more precise than that simulated in our previous study. Likewise, iso-loss curves represented combinations of crop age and the leaf folder damage that resulted in a similar yield loss. These decision support tools would facilitate accurate monitoring of the leaf folder damage to ensure judicious pesticide application.  相似文献   
68.
Hyperaccumulating plants are increasingly investigated in combination with EDTA addition to soil for phytoremediation of heavy metal contaminated soils. A 60-day incubation experiment was carried out to investigate the effects of heavy metal release during the decomposition of Zn-rich (15.7 mg g?1 dry weight) Arabidopsis halleri litter on C mineralization, microbial biomass C, biomass N, ATP, and adenylate energy charge (AEC). These effects were investigated in two soils with different Zn, Cu, and Pb levels, with and without EDTA addition to soil. The sole addition of Zn-rich A. halleri litter to the two soils did not increase the contents of NH4NO3 extractable Zn, only with the combined additions of EDTA and litter was there a considerable increase, being equivalent to three times the added amount in the low metal soil and to 50% in the high metal soil. Litter amendment increased the CO2 evolved; being equivalent to 44% of the added C in the two soils, but EDTA addition had no significant effect on CO2 evolution. Litter amendment resulted also in an 18% increase in microbial biomass C, 27% increase in ATP and 6% increase in AEC in the two soils, but EDTA had again no effect on these indices at both metal levels. In contrast, the sole addition of litter had no effect on microbial biomass N, but EDTA addition increased microbial biomass N on average by 49%. The application of EDTA for chelate-assisted phytoextraction should in the future consider the risk of groundwater pollution, which is intensified by resistance of EDTA to microbial decomposition.  相似文献   
69.
A study at selected action sites in semi-arid region of Andhra Pradesh, India, showed widespread land degradation due to low levels of soil organic carbon (78% of fields) and deficiencies of available nutrients like phosphorus (34%), sulfur (93%), calcium (33%), zinc (84%), boron (73%), and copper (33%). Soil test-based addition of deficient micro- and macronutrients increased food grain production by 30–40% and straw (which is used as fodder) production by 10–30%. Micro-watershed scale low-cost cement-lined farm-ponds at smallholder farm level proved a scalable technology for drought-proofing of crops resulting into additional crop yield by more than 30% during 2015. Augmentation of water sources also facilitated farmers’ to successfully diversify the production system. Shared machinery resources improved the operational and economic efficiency of farm sowing operations through higher crop yields by around 10%. We conclude that a mix of low-cost critical interventions if out-scaled in a large number of dryland small holdings through policy support may not only improve productivity and livelihoods, but also enhance their abilities to effectively cope with the climatic aberrations.  相似文献   
70.
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