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41.
An experiment was conducted to assess the effects of different sources of fats added with an external emulsifier (lecithin) on the performances of Khaki Campbell Ducks in an eight-week trial. Ducks were grouped into five dietary groups with three replicates (n = 10) in each group. The ducks were fed with a basal diet supplemented with 3% soybean oil and without emulsifier (C1), 3% palm oil without emulsifier (C2), 3% soybean oil with emulsifier (T1), 3% palm oil with emulsifier (T2) and 3% lard with emulsifier (T3). The growth performance of ducks did not vary (P > 0.1) among the dietary treatments. Feed intakes by ducks were also similar (P > 0.1) among treatments within the periods. Similarly, feed intake to gain ratios were not affected by any dietary treatments. The metabolizability of dry matter, crude protein and nitrogen free extract also did not change (P > 0.1) due to various dietary treatments. However, the metabolizability of fats in all the emulsifier added groups (T1, T2 and T3) was greater (P < 0.05) than the dietary groups without emulsifier (C1 and C2). Various carcass traits such as percentages of hot carcass, breast, legs, lungs, hearts, gizzard, giblets weights relative to bodyweights did not vary (P > 0.1) among the groups. The carcass yield tended (P = 0.06) to be greater in the T1 than in the C1 group. The moisture, fats, protein and ash composition of meat (percent on fresh basis) was similar (P > 0.1) among treatments. In conclusion, supplementation of lecithin as an emulsifier to the diets containing different sources of fats (3%) appears to have no major impact on the overall performances of Khaki Campbell ducks in their grower phase.  相似文献   
42.
Meat yield of 233 individuals of giant freshwater prawn, Macrobrachium rosenbergii (de Man, 1879), and their morphometric relationships were examined. Morphometric parameters of different length and weight measurements were recorded for both the sexes separately and subjected to analysis. The meat yield of prawns was size and sex dependent with females showing significantly greater (P < 0.05) tail meat yield than males. The tail meat as a body weight percentage ranges from 26.12 to 40.75 and 32.97 to 42.11 in males and females, respectively. Much of the differences in yield are related to the size and weight of the head and claws. The head weight of males was observed to be higher compared to females in all the size classes. Regression slopes of total length versus body weight and total length versus head weight were significantly higher than critical isometric value indicating high positive allometric growth in both the sexes, with males showing significantly higher (P < 0.05) slope than females. The relationship parameters of total length versus tail weight and total length versus tail meat showed a positive allometric growth in females, whereas it is isometry and negative allometry in males. The morphometric relationship of tail length versus all weight measurements showed positive allometry and negative allometry in females and males, respectively.  相似文献   
43.
The present study examined the variation in survival, proportion of male morphotypes, female and male proportion, female reproductive status and tag losses in nine crosses from a complete (3 × 3) diallel mating of three populations of Macrobrachium rosenbergii in India. The populations originated from Gujarat (north‐west), Kerala (south‐west) and Odisha (east), representing different agro‐ecological regions in India. Progeny from 60 families (4773 juveniles) were individually tagged and reared for 16–17 weeks in earthen ponds. Binary logistic regression was used to analyse the data. Survival rate was greatest (0.88) for Kerala × Odisha (KO; the first letter represents the sire), whereas it was lowest (0.75) for both Kerala × Kerala (KK) and Gujarat × Kerala (GK). Significantly greater proportions of large male morphotypes were observed in KK cross and in combinations involving Kerala population. The highest proportion of immature females, as well as of non‐berried females, was observed in the Odisha × Odisha (OO) cross. Tag loss was greatest for KK (0.35) and lowest for GG (0.19). We found significant variations among crosses for all studied traits suggesting the possibility of including them in genetic improvement programmes of this species.  相似文献   
44.
Out of 1 989 wild accessions sown in seed boxes for screening, only 1 003 wild accessions with good germination were screened against brown planthopper (BPH), Nilaparvata lugens (Stål) under greenhouse conditions. The collection comprised of accessions from 11 wild species and African cultivated rice. The germplasm was screened for BPH following standard seed box screening technique in the greenhouse. As many as 159 accessions were identified as resistant during the year 2012 based on one year screening. A selected set of BPH resistant accessions were screened again during 2013. Based on the two years screening, seven accessions of O. nivara (AA), one accession of O. officinalis (CC), seven accessions of O. australiensis (EE), five accessions of O. punctata (BB and BBCC) and nine accessions of O. latifolia (CCDD) were confirmed to be resistant to BPH. So far no BPH resistance genes have been identified and designated from O. nivara and O. punctata, hence these may act as new sources of resistance.  相似文献   
45.
Laboratory incubation experiments were conducted with uncoated urea or urea coated with dementholized oil (DMO), pitch (the mint oil discard), terpenes (the products of menthol mint oil), or dicyandiamide (DCD) to study the retardation of urea hydrolysis and nitrification in soil. Two levels (0.5 and 1 %) of coating were tested. Urea was applied at a rate of 200 mg kg−1 of dry weight of soil. The urea hydrolysis and nitrification processes were inhibited by all three natural products. All the three natural products viz., DMO, terpenes, and pitch significantly retarded urease activity of soil.  相似文献   
46.
Spinach grown in cadmium (Cd)-contaminated soils accumulates Cd compounds in toxic concentration contaminating the food chain leading to the chronic toxic effects on human and animal health. A study was conducted in a Cd-contaminated soil to examine the ameliorative effect of lime and organic manure on the mobility of Cd and its uptake in spinach. Application of lime or organic manure or both decreased the Cd concentration in soil and shoots and increased chlorophyll content of leaves. As compared to the control treatment, combined application of lime and organic manure decreased the level of Cd in soil by 54.7%, in spinach shoot by 61.3%, and the transfer factor of Cd by 35.0% and increased in leaf chlorophyll content by 29.4%. Combined application of lime and organic manure emerged as a viable option in reducing the mobility of Cd in contaminated soil for growing spinach.  相似文献   
47.
Eight 6–9 month old calves, showing clinical signs of intermittent haemoglobinuria, even after treatment with an antipiroplasmal drug (4,4-diamidinodiazoaminobenzene diaceturate), were examined for oxidative damage to their erythrocytes and the presence of hemoprotozoa in blood smears. Four calves without signs of haemoglobinuria served as controls. The blood smears from three of the eight calves contained piroplasms for Theileria annulata. Irrespective of the presence of piroplasms in their blood smears, the calves with haemoglobinuria had significantly (p<0.01) lower haemoglobin concentrations (Hb) and packed cell volumes (PCV). The lipid peroxide level in the erythrocytes, but not in the plasma, of calves with red urine was significantly (p<0.05) higher than that for the controls. It is concluded that haemoglobinuria, irrespective of the presence of piroplasms in blood smears, is associated with oxidative stress to erythrocytes and peroxidation of polyunsaturated fatty acids of cell membrane.  相似文献   
48.
Antibacterial activity of luteoforol from Bridelia crenulata   总被引:1,自引:0,他引:1  
The methanol extract of Bridelia crenulata stem bark (50-1.5625 mg/ml) and its isolated luteoforol (2-0.25 mg/ml) showed concentration-dependent inhibiting activity against all 10 tested bacteria.  相似文献   
49.
We investigated the dynamics of N and P availability in the rhizosphere of Bt and non- Bt cotton crops during their growth. In a net-house pot culture experiment at the Indian Agricultural Research Institute, New Delhi, Bt -cotton (cv. MRC-6301 Bt ) and its non-transgenic near-isoline (MRC-6301) were grown on a sandy loam soil until maturity. A control (no-crop) treatment was also included. Rhizosphere soil and root samples were collected at 60, 90, and 120 days after sowing (DAS). Soil samples were analysed for dehydrogenase activity, soil respiration, mineral-N and Olsen-P. Results have revealed a significant reduction in dehydrogenase activity (−17 %) and soil respiration (−3.5 %) in the rhizosphere of Bt -cotton over non- Bt isoline. Total mineral-N (NH4+-N +      -N) in soil was reduced by 14 %, whereas Olsen-P was increased by 8 % because of Bt -cotton. Root biomass yields were not different (P   >   0.05), but root volume was significantly higher in Bt than non- Bt isoline. Time of sampling strongly (P   <   0.05) affected the above parameters, showing their highest values at 60 or 90 DAS. A significant interactive effect of sampling time and treatments was also indicated. Our results suggest that Bt -cotton may constrain the availability of N, but enhances P-availability in these soils.  相似文献   
50.
 A study was conducted to determine mineralization rates in the field and in different soil layers under three grassland managements (viz. a reseeded sward, a permanent sward with a conventional N management, and a long-term grass sward with 0 N (0-N) input). Potential mineralization rates of soil particles (sand, silt and clay) and macro-organic matter fractions of different sizes (i.e. 0.2–0.5, 0.5–2.0 and >2 mm) were also determined in the laboratory. In the reseeded plots, net mineralization was unchanged down to 40 cm depth. In the undisturbed conventional-N swards, mineralization rates were substantially higher in the top layer (0–10 cm) than in the deeper layers. In plots which had received no fertilizer N, mineralization was consistently low in all the layers. There was more macro-organic matter (MOM) in the 0-N plots (equivalent to 23 g kg–1 soil for 0–40 cm) than in the two fertilized plots (i.e. conventional-N and reseeded) which contained similar amounts (ca. 15 g kg–1 soil). C and N contents of separated soil particles did not differ amongst the treatments, but there were large differences with depth. Potential mineralization in the bulk soil was greatest in the 0–10 cm layers and gradually decreased with depth in all the treatments. Separated sand particles had negligible rates of potential mineralization and the clay component had the highest rates in the subsurface layers (10–40 cm). MOMs had high potential rate of mineralization in the surface layer and decreased with soil depth, but there was no clear pattern in the differences between different size fractions. Received: 17 November 1997  相似文献   
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