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21.
This study assessed the effects of dietary selenium (Se), iodine (I) and a combination of both on growth performance, thyroid gland activity, carcass characteristics and the concentration of iodine and selenium in Longissimus lumborum (LL) muscle in goats. Twenty‐four bucks were randomly assigned to four dietary treatments: control (CON), basal diet without supplementation, basal diet + 0.6 mg Se/kg dry matter (DM) (SS), 0.6 mg I/kg DM (IP), or combination of 0.6 mg/kg DM Se and 0.6 mg/kg DM I (SSIP) and fed for 100 days. Animals fed diet SSIP exhibited higher (P < 0.05) body weight and better feed conversion ratio (FCR) than those fed other diets. Dressing percentage of goats fed the supplemented diets was higher (P < 0.05) than that of the control. Carcasses from the IP group had higher (P < 0.05) total fat proportion than the SSIP group. The levels of both elements were significantly elevated (P < 0.05) in LL muscle in supplemented goats. Thyroid follicular epithelial cells of IP and SSIP animals were significantly higher than those of CON and SS groups. The study demonstrated that the combined Se and I dietary supplementation improves growth performance, carcass dressing percentage and increases the retention of Se and I in goat meat.  相似文献   
22.

Bovine anaplasmosis is endemic in Pakistan where it reduces livestock productivity and leads to high mortality, especially in young animals. This study was aimed to identify the potential risk factors responsible for the occurrence and spread of anaplasmosis in cattle and buffaloes for the first time in Pakistan. A total of 900 (cattle?=?479, buffalo?=?421) blood samples were collected irrespective of age and sex from three distinct zones of Khyber Pakhtunkhhwa (KP) province of Pakistan. Polymerase chain reaction (PCR) technique was used for the molecular detection of anaplasmosis. Data collected on a piloted questionnaire including 11 predicting variables which were analyzed using R-statistical software, and association between the dependent and independent variables was assessed using univariable analysis. Automated and manual approaches were exercised, producing comparable models. Key risk factors identified in all the approaches included species of the animal, breed of animal, sex of animal, tick infestation status, previous tick history, tick control status, and acaricides used (odds ratio?>?1). The 611 bp DNA fragment specific for 16S rRNA gene of Anaplasma spp. was produced from 165 samples. The samples were confirmed for anaplasmosis through sequencing and BLAST queries. The findings of the current study conclude that by enhancing the protective measures to control the identified risk factors can reduce the spread of anaplasmosis in Pakistan.

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23.
The physicochemical and gel properties of myofibrillar protein (MFP) from sin croaker fish were studied during ice storage for 18 days. Significant changes in the trends of solubility, Ca2+ ATPase enzyme activity, surface hydrophobicity, and water holding capacity of extracted MFP were observed by the 6th day of storage. The Ca2+ ATPase enzyme activity reduced significantly (p < 0.05) by the 6th day of storage. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) did not show a remarkable change in the concentration of myosin heavy chain. Surface hydrophobicity increased almost four times from its original value of 18.98 µg; whereas, water holding capacity showed a fluctuating trend during storage. The emulsion capacity of the MFP was in the range of 0.89- to 1.92-mL oil/mg protein during storage. The gel strength value (313.45 g.cm) of heat-induced gel prepared from fresh minced meat decreased significantly (p < 0.05) by the 6th day of ice storage. Texture profile analysis revealed that changes in hardness and gumminess were concurrent to steeply reducing breaking force up to the 6th day. The histological observation showed gradually increasing gaps between muscle fibers. The histological observations and physicochemical quality indicated that the sin croaker fish can be used for producing good quality surimi when stored for up to 6 days in ice.  相似文献   
24.
Effect of blanching and cooking on the quality of Pacific white shrimp with skeletal muscle severed (by beheading and peeling) at different stages of rigor was evaluated. Peeling and beheading shrimp in post-rigor stage resulted in higher yields compared to shrimp in in-rigor and pre-rigor stages. Weight loss due to blanching/cooking was highest when skeletal muscle was severed in in-rigor stage followed by post- and pre-rigor stages. Highest crude and sarcoplasmic protein contents were found in the shrimp blanched or cooked while in in-rigor stage followed by pre-rigor and post-rigor stages. Hardness, springiness, and chewiness were found to be better in the shrimp blanched in pre-rigor stage. Highest sensory scores for color, appearance, succulence, and odor were found for shrimp blanched or cooked in pre-rigor followed by in-rigor stage. Instrumental analysis of color and texture confirmed the sensory scores.  相似文献   
25.
ABSTRACT

Breading and battering of fish results in a physically superior product with a higher economic value from low-value fish. The present work was undertaken to evaluate three conventional breading materials for fish cutlets. Standard sized fish cutlets were molded with and dipped in a batter mix, followed by breading with bread crumbs (CB), pressed rice (PR), or noodle vermicelli (NS). The products were evaluated for coating parameters such as pickup, adhesion degree, cooking loss, and frying yield. The coating pickup ranged from 10.95% to 36.00%, and a maximum pickup was found with pressed rice (PR). Similarly, the adhesion degree in PR was 26.47%, which was highest among the three. Cooking loss was highest with control (conventional breadcrumb) at 15.92%. After analyzing the frying yield, it was found that PR yielded the maximum at 16.75% and less oil absorption. PR also had significantly (p < .05) higher hue angle value than both the NS and CB. Maximum browning and tough texture was observed in the NS sample. Frying tolerance was better with PR breading, which maintained better color during deep frying operations. This study can help industries to utilze low-cost breading material in preparing enrobed snack products.  相似文献   
26.
Random amplified polymorphic DNA (RAPD) markers were used to estimate the genetical variability of three salt-resistant genotypes, SARC-1, SARC-5 and S-24, exposed to saline environment. High-yielding and salt-sensitive variety MH-97 was used as standard for comparison. The behavior of these genotypes under saline environment was analyzed by using the hydroponics screening methods at the seedling stage. One hundred and fifty primers were tested of which 52 primers revealed differences between SARC-1 and SARC-5, 54 revealed differences between SARC-1 and S-24 and 61 revealed differences between SARC-5 and S-24. Polymorphism differences between MH-97 and SARC-1, MH-97 and SARC-5 and MH-97 and S-24 were 53%, 64% and 42%, respectively. Four primer pairs amplified special fragments, which were located in all the three salt-resistant genotypes but none on the salt-sensitive genotype MH-97. Primer GLD-15 (5?-CCGTGGCATT-3?) generated a prominent fragment of length 1460 bp; primer GLF-18 (5?-ACCCGGAACC-3?) produced a fragment of length nearly 980 bp in the salt-resistant genotype; the primer pair GLE-5 (5?-TTCAAGCCCG-3?) located one polymorphic amplified band of 1290 bp and the primer GLH-9 (5?-ATCCAGGTCA-3?) performed as a weak polymorphic band of 640 bp, respectively.  相似文献   
27.
Antioxidants play an important role in adapting plants to abiotic stress by detoxifying reactive oxygen species (ROS). Involvement of antioxidant enzymes in abiotic stress tolerance of highly stress‐tolerant quinoa was studied in a climatic chamber at 6 mOsm (milliosmolar) ionic (300 mm NaCl) and non‐ionic (600 mm mannitol) salts combined with increasing levels of potassium K1 and K2 (6, 12 mm ), respectively. Fifteen days of salt treatment (both ionic and non‐ionic) decreased plant growth (shoot and root fresh weight), stomatal conductance and chlorophyll content index. Furthermore, both forms of salt stress increased the activities of superoxide dismutase, catalase, ascorbate peroxidase and peroxidase up to 2.33‐, 3.98‐, 4.78‐ and 5.55‐folds, respectively, compared to no salt treatment, whereas membrane stability index decreased corresponding to increase in lipid peroxidation (malondialdehyde), with salt treatments compared to non‐stressed plants. However, no significant effect of potassium and salt treatments has been noticed on the maximal photochemical efficiency of PSII. The results suggested that enhanced antioxidant enzymes activity under salt stress could be one of the factors responsible for abiotic stress tolerance in quinoa.  相似文献   
28.
Straw incorporation is a widespread practice to promote agricultural sustainability. However, the potential effects of straw incorporation with the prolonged time on nitrogen (N) runoff loss from paddy fields are not well studied. The current study addresses the knowledge gap by assessing the effects of straw incorporation on the processes influencing N runoff patterns and its impacts on crop yield, N uptake, total N (TN), and soil organic matter (SOM). We conducted field experiments with rice (Oryzasativa L.)–wheat (Triticumaestivum L.) rotation, rice–tobacco (Nicotianatabacum L.) rotation, and double-rice cropping in subtropical China from 2008 to 2012. Each rotation had three N treatments: zero N fertilization (CK), chemical N fertilization (CF), and chemical N fertilization combined with straw incorporation (CFS). The treatment effects were assessed on TN runoff loss, crop yield, N uptake, soil TN stock, and SOM. Results showed that TN runoff was reduced by substituting part of the chemical N fertilizer with straw N in the double rice rotation, while crop N uptake was significantly (P<0.05) decreased due to the lower bioavailability of straw N. In contrast, in both rice–wheat and rice–tobacco rotations, TN runoff in CFS was increased by 0.9–20.2% in the short term when straw N was applied in addition to chemical N, compared to CF. However, TN runoff was reduced by 2.3–19.3% after three years of straw incorporation, suggesting the long-term benefits of straw incorporation on TN loss reduction. Meanwhile, crop N uptake was increased by 0.8–37.3% in the CFS of both rotations. This study demonstrates the challenges in reducing N runoff loss while improving soil fertility by straw incorporation over the short term but highlights the potential of long-term straw incorporation to reduce N loss and improve soil productivity.  相似文献   
29.
A pot experiment was conducted in sandy clay loam saline-sodic soil to assess the effects of farm yard manure (FYM), municipal solid waste (MSW) composts and gypsum application on nitrate leaching, soil chemical properties and crop productivity under rice-wheat cropping system. It also aims at establishing the correlation between soil phsico-chemical properties and yield response using principle component analysis and Pearson correlation analysis. The MSW was decomposed aerobically, an-aerobically and co-composted. Maximum nitrate leaching was observed during rice (75.9 mg L?1) and wheat (37.2 mg L?1) with an-aerobically decomposed MSW as compared with control treatment. Results revealed a decrease in soil pH (?6.95% and ?8.77%), electrical conductivity (EC) (?48.13% and ?51.04%), calcium carbonate (CaCO3) (?40.30% and ?48.96%), and sodium adsorption ratio (SAR) (?40.27% and ?45.98%) with an-aerobically decomposed MSW compost during rice and wheat, respectively. In this treatment, organic matter (OM) (93.55% and 121.51%) and cation exchange capacity (CEC) (19.31% and 31.79%) were the highest as compared with control treatment during rice and wheat, respectively. Rice and wheat growth were significantly (p≤ 0.05) increased by an-aerobically decomposed MSW followed by co-compost, aerobically decomposed MSW, FYM, gypsum and control. Furthermore, Pearson correlation coefficients predicted significant positive correlation of yield with soil OM, and CEC while inverse relationship was observed with EC, pH, CaCO3, and nitrogen use efficiency. Soil amelioration with organic and gypsum amendments was further confirmed with principal component analysis. This study has proved an-aerobically decomposed MSW as an effective solution for MSW disposal, thereby improving soil chemical properties and crop productivity from sandy clay loam saline-sodic soil.  相似文献   
30.
Bioavailability and mobility of lead (Pb) in soils depend upon their partitioning between solution-solid phases and their further fractionation and redistribution among different solid-phase components. However, the dynamics of Pb in salt-affected (saline–sodic) Pb-contaminated (polluted) paddy soil need more exploration particularly under the influence of application of amendments at varying hydrological regimes and residence time. In this context, an incubation study was conducted to investigate the effect of application of three inorganic amendments (gypsum, rock phosphate and diammonium phosphate) on Pb fractions at two soil moisture regimes (flooding regime and 75% field capacity) and two incubation times (after 2 and 30 days) successively in non-saline/sodic and saline–sodic Pb-polluted paddy soils. After applied treatments, the concentration of Pb in five, i.e., exchangeable (F1), carbonate (F2), Fe–Mn oxide (F3), organic matter and sulfide bound (F4) and residual (F5) fractions, was assessed by sequential extraction. The results showed that the Pb spiked in the soils was significantly (P?≤?0.05) transformed from easily extractable (exchangeable and carbonate) fractions into less labile (Fe–Mn oxide, OM–S bound and residual) fractions. Among tested amendments, gypsum performed better in reducing the lability of Pb followed by DAP.  相似文献   
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