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1.
The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68?±?0.6 kg, 4–5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P?< 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P?< 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P?< 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P?< 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P?<?0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P?< 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P?< 0.05) neutrophils, basophils and serum urea and greater (P?<?0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition.  相似文献   
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Background

In Kenya, rice (Oryza sativa L.) is mainly produced under irrigation by small-scale farmers. Mwea irrigation scheme (MIS) in Kirinyaga County accounts for 80–88% of rice production. Here, rice is the main source of livelihood and a source of revenue generation for the county. However, a recently established invasive freshwater snail, Pomacea canaliculata (Lamarck) (family: Ampullariidae), a species of apple snail, presents a serious threat to rice production.

Results

Household surveys, focus group discussions and key informant interviews highlight apple snail as a serious problem in MIS. Households that observed at least a moderate level of infestation (>20% of cultivated area) experienced significant reductions in rice yield (~14%) and net rice income (~60%). Farmers reported increased use of chemical pesticides for management of apple snail. In addition, the cost of hired labor for physical removal of egg masses and snails is resulting in substantial negative effects on net income. Farmer age, area of land owned, responsibility for decision-making, receipt of extension advice, training, and membership of a farmer organization, were all statistically significant variables to explain farmers awareness of the need for area-wide apple snail management.

Conclusion

Strategies to limit the spread of apple snail are urgently needed. A Multi-Institutional Technical Team (MITT) has been established to spearhead management efforts and consolidate advice to farmers on how to manage apple snail. However, without action to mitigate spread, the consequences could be disastrous for rice production and food security in Kenya, and for other rice growing regions across Africa. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
4.
This study examines the strategies and benefits of the taungya farming system to both the government and the rural economy in Nigeria. An interview survey was conducted in which data were collected from 115 randomly selected farmers in five villages in the Oluwa forest reserve, Ondo State, Nigeria. The study examines the extent of participation of rural dwellers in plantation development through taungya farming and the degree of success of this system as an afforestation method. The farmers were predominantly illiterate, within the age bracket of 35–54 years and with small farm holdings. Twenty nine percent relied totally on food from the forest reserve for their livelihood, while 71% also had farm holdings in free areas. Land within the reserve is allocated to farmers free of charge but compensation is paid to landlords on land from free areas. A statistically significant difference was detected in income from the two sources of farmland for the households and but not in the size of land allocated under taungya and free areas. About 184 farmers are involved in taungya annually, and 410 ha of Tectonia grandis has been established for the government of Ondo State.  相似文献   
5.
  1. The apparent (AIAAD) and standardised ileal amino acid digestibility (SIAAD) of wheat distillers dried grains with solubles (wheat-DDGS) was determined for broilers and turkeys at 28 d using two experiments.

  2. A total of 84 male Ross 308 broiler chicks (Experiment 1) or 84 male BUT 10 turkey poults (Experiment 2) were offered a nutrient-adequate diet from d 1 to 23. On d 23, birds in each experiment were allocated to 4 treatments consisting of a nitrogen-free diet (NFD) (with or without protease) and an assay diet containing wheat-DDGS as the only source of amino acids (with or without protease) in a randomised complete block design.

  3. In Experiments 1 and 2, the coefficient of AIAAD or SIAAD of Lys and Asp were low irrespective of protease. In Experiment 1, the coefficient of AIAAD ranged from 0.35 (Ala) to 0.75 (Pro) without protease, whereas the range was 0.42 (Thr) to 0.82 (Pro) with protease. Protease improved the coefficient of AIAAD for Arg and Pro and tended to improve the coefficient of AIAAD for Met. Without protease, the coefficient of SIAAD ranged from 0.51 (Ala) to 0.84 (Pro), whereas the range was from 0.65 (Ala) to 0.93 (Pro) with protease. Protease improved the coefficient of SIAAD of Arg, Leu, Phe, Met, Val and Pro.

  4. In Experiment 2, the coefficient of AIAAD was lower than 0.50 for all amino acids except for Glu (0.70) and Pro (0.81) without protease. On the other hand, the coefficient of SIAAD ranged from 0.41 (Thr) to 0.89 (Pro) without protease, whereas the range was from 0.56 (Arg) to 0.88 (Pro) with protease supplementation. With the exception of Cys and Pro, protease improved the coefficient of AIAAD and SIAAD of all other amino acids by 0.05–0.19.

  5. It was concluded that the AIAAD and SIAAD of wheat-DDGS are variable and are generally greater in broilers compared to turkeys at 28 d of age. Protease improved the ileal digestibility of a large number of amino acids in wheat-DDGS for broilers and turkeys.

  相似文献   
6.
Journal of Pest Science - The two-spotted spider mite, Tetranychus urticae Koch, is a constant threat to sustainable production of numerous economically important crops globally. Management of T....  相似文献   
7.
Induced breeding trials of two clariid catfishes, Clarias gariepinus and Heterobranchus bidorsalis , were conducted using five doses (2, 4, 6, 8 or 10 mg/kg) of acetone-dried tilapia pituitary (ADTP) extracts. Oocyte maturation and ovulation were induced in female catfishes by single intramuscular injection of 6–10 mgkg ADTP; optimum results were obtained with 8 mgkg in both catfishes. At ambient temperature (27 ± 1 C). ovulation occurred within 14–18 h post-injection resulting in 16–20% increase in egg diameter. Fertilization and hatching percentages increased ( P < 0.05) with increases in hormone dosage. Survival of fry fed a mixed zooplankton diet was high (ranging from 79% to 85%) after 30 d of rearing.  相似文献   
8.
The characterisation of the small ruminant populations in developing countries will play a major role in the maintenance of the genetic resources as the basis for future improvement in livestock production. The present study aimed at morphological characterisation of the two main breeds of sheep in Ghana by assessing variation within and between breed populations using principal component and discriminant analyses. The two breeds were the Sahel and the Djallonke sheep of both sexes and of two groups namely, young (1 year old, consisting of 74 animals) and mature sheep (≥2 years old, comprising 219 animals). The analysis of variance revealed significant (P?<?0.05) differences in the morphological traits of the Sahel and the Djallonke sheep breeds with higher values recorded for the former. Sexual dimorphism was in favour of male animals in all the morphological traits examined. Mature animals also had comparative advantage over the young. Two principal components were extracted to discern the structure of the two genetic groups. The most discriminating traits between the two sheep breeds were rump height, height at withers, neck girth and pin-bone width. Mahalanobis distance between the two genetic groups was 5.723 (P?<?0.0001). The developed discriminant functions clearly discriminated and classified the Sahel and the Djallonke sheep into their breeds of origin, thus yielding 100, 93.4 and 90.4 % accurate classification for the rams, ewes and the overall sheep population, respectively. The present approach would greatly help in establishing management and conservation policies for the sustainable production of the two Ghanaian sheep breeds.  相似文献   
9.
This study assessed the effects of exploitations in natural forest ecosystems on tree species diversity and environmental conservation. This was achieved by comparing tree species diversity and yield in an unlogged forest (Strict Nature Reserve) and a forest reserve where active logging is in progress in Ondo State, Nigeria. Eight plots (20 m × 20 m) were assessed in each site using systematic sampling techniques. All living trees with dbh >10 cm were identified, categorized into families with their diameter at breast height (dbh) measured in each plot. Shannon-Weiner and species evenness indices were used to assess and compare tree species diversity and abundance. The results show that the tropical humid forest is very rich in tree species, as a total of 54 different tropical hardwood species from 23 families were encountered in both forest types. There were 46 species distributed among 21 families in the unlogged forest and 24 species in 14 families in the logged forest. Shannon-Weiner diversity index of 3.16 and 3.03 and evenness index of .83 and .81 were also obtained for the unlogged and logged forest, respectively. Every variable computed had a higher value in the unlogged forest relative to the logged forest. In the unlogged forest, the species with the highest number of occurrence was Mansonia altissima A. Chev. (80 stems/ha). Caesalpinoidae and Sterculiaceae families had the highest number of species (6). In the logged forest, Triplochiton scleroxylon K. Schum. (18 stems/ha) had the highest frequency and Caesalpinoidae family has the highest number of species (4). The study concludes that exploitation has affected species diversity in the ecosystem and subsequently, the roles of trees in environmental conservation are affected.  相似文献   
10.
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