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11.
The agronomic characteristics of different legume cover crops and their effects on soil chemical properties were investigated in a short-term field study. We compared weed biomass, nitrogen equivalence, growth rate, leaf chlorophyll content, cover crop biomass, soil total organic carbon, and soil total nitrogen under eight different legume cover crops in a short-term field experiment. We found the highest growth rate, cover crop dry biomass, N plant content, and N contribution with C. ochroleuca plants, whereas for leaf chlorophyll content, soil organic carbon, and total nitrogen the highest values were found with M. pruriens. We did not find any significant difference among C. ochroleuca and M. pruriens for cover crop dry biomass. Our findings suggest that the incorporation of cover crops into the soil can change positively the soil chemical properties, such as soil organic carbon and total nitrogen. Our results also highlight the importance of considering the short-term effect of cover crops on the tropical soil fertility maintenance, in this case, Regosol.  相似文献   
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The current study examined the protective effects of l ‐glutamine and cytochalasin B during vitrification of immature bovine oocytes. Oocyte vitrification solution (PBS supplemented with 10% FCS, 25% EG, 25% DMSO and 0.5 m trehalose) was the vitrification control. Treatments were the addition of 7 μg/ml cytochalasin B, 80 mm glutamine or both cytochalasin and glutaminine for 30 s. After warming, oocytes were matured in vitro for 24 h, fixed and stained with Hoechst (33342) for nuclear maturation evaluation. l ‐glutamine improved the vitrified/warmed immature bovine oocytes viability (32.8%), increasing the nuclear maturation rates compared to other treatments and the no treatment vitrified control (17.4%). There was, however, no effect of cytochalasin B on in vitro maturation (14.4%).  相似文献   
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The influence of agricultural management practices, such as organic fertilisation and plant densities on soil properties, root growth, and sesame yield were investigated. Soil samples (depth of 0–20 cm) were taken from a field study with sesame (Sesamum indicum L.) cultivated on a Chromic Luvisol, which was conducted to explore the effects of six fertilisation systems [Non-fertilisation (Control); Mineral fertilisation (Min); Organic fertilisation with 2 (Org-1) and 3 Mg ha–1 (Org-2) of commercial organic fertiliser Organus B; and with 1 (Tak 1) and 2 Mg ha–1 (Tak-2) of commercial organic fertiliser Takamix] and two plant densities [111111 (Pdens1) and 55555 (Pdens2) plants ha–1), in a factorial design (6 × 2) with four blocks. The highest values of soil organic carbon, total nitrogen, root density and sesame yield were found in the Org-2 fertilisation and Pdens1 treatments. We found that organic fertilisation combined with Pdens1 significantly increased root growth. Organic fertilisation treatments were able to maintain 80% of sesame roots distributed at a soil depth of 0–10 cm, whereas the last 20% were distributed at a soil depth of 10.1–20 cm. In conclusion the utilization of commercial organic fertilisers as an organic matter source enhanced soil organic carbon, total nitrogen, and root density that contributed to increase sesame yield. Our findings also suggest that inputs of organic matter source with a correct plant density might change positively soil organic carbon and total nitrogen, root growth, root distribution and sesame yield.  相似文献   
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The influence of long-term fertilization on plant development and soil properties was investigated. Soil samples were taken from a long-term field experiment which was conducted for 5 years to explore the effect of three treatments: control (non-fertilization), conventional (mineral fertilizers—NPK), and alternative (organic fertilizers—farmyard manure). The highest values of plant yield and soil properties were found in the alternative fertilization system after the thirty year of its utilization. Conventional fertilization showed positive effects until the second year of its utilization where enhanced soil fertility (total nitrogen and available phosphorous content) and plant development (plant yield, plant dry biomass, plant phosphorous concentration, and plant nitrogen concentration). After the thirty year the conventional fertilization system showed lower values for these studied variables compared to alternative fertilization system. Our findings suggest that inputs of organic matter source can change positively the wheat growth and soil fertility, and these results highlight the importance of considering the long-term effect of mineral and organic fertilizers on these variables.  相似文献   
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The aim of this study was to verify the in vivo effectiveness of pumpkin seed (Curcubita pepo Linnaeus, 1753) in naturally infected ostriches in the Cariri zone, semiarid region of Paraíba State, Brazil. Forty-eight ostriches were used, African Black breed, of 14 to 36 months old, naturally infected by gastrointestinal nematodes. These animals were divided into four groups of 12 ostriches. Group 1 consists of animals treated with 0.5 g/kg live weight (l. w.) of pumpkin seed meal; group 2 received 1 g/kg l. w. of pumpkin seed meal; group 3 was treated with Albendazole 5 %, at the dosage of 1 mL/10 kg l. w.; and Group 4 was the control group and do not received treatment. Groups 1 and 2 received the treatment for three consecutive days, orally, at intervals of 7 days, totaling nine administrations. The Albendazole 5 % was administered one time, at the beginning of the experiment, according to the manufacturer’s recommendations. The groups treated with pumpkin seed showed a significant decrease in egg counts per gram of feces (EPG), wherein group 2 (1 g/kg l. w.) was the most effective. The control and drug groups showed no reduction in EPG. The results of the present study demonstrate that the administration of pumpkin seed was effective in controlling gastrointestinal helminths in naturally infected ostriches.  相似文献   
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The present study aimed to evaluate the renal and hepatic responses in eight dogs with visceral leishmaniasis submitted to treatment with meglumine antimoniate and to verify the occurrence of possible side effects. Urinalysis, hepatic and renal function tests were carried out in all animals at up to seven moments. After the end of a six-month observation period, all dogs were euthanized. Before the beginning of the experiment urinary and biochemical alterations were observed in four dogs due to the changes caused by the parasite itself. These alterations included the presence of renal cells, cylindruria, proteinuria, azotemia, hyperproteinemia and hypoalbuminemia. One dog died on the third day after treatment because an aggravation of the clinical picture, probably due to the medication. During the course of the study, an increase in hepatic enzymes was verified in two animals. Sixty days after the beginning of the treatment four dogs showed remission of clinical signs. The other three were asymptomatic with persistent biochemical alterations. From these, two presented recurrence of clinical signs about 150 days after the beginning of the treatment while in the other, hyperproteinemia persisted. Meglumine antimoniate was not efficient to treat dogs with severe renal dysfunction and the side effects observed were pain at the site of injection and the probable transient hepatotoxicity, evidenced by biochemical examinations, but without the presence of clinical signs.  相似文献   
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Aiming to evaluate the efficacy of the treatment of canine visceral leishmaniasis, to verify the occurrence of a possible disease relapse, and to search for the presence of the parasites after the end of the treatment, seven dogs naturally infected by Leishmania (Leishmania) chagasi were used. The dogs were subjected to a treatment with 75 mg/kg meglumine antimoniate subcutaneously every 12 h for 21 days, and followed-up for a period of 6 months. During the whole experimental period the animals wore deltamethrin collars and were kept in a screened kennel to avoid reinfection. Lymph node and bone marrow aspiration biopsy was carried out to search for the parasite at seven moments: before the treatment, 30, 60, 90, 120, 150 and 180 days after the start of the treatment. After the end of the experiment all dogs were humanely euthanized. Then, spleen and liver "imprints" and in vitro cultures were carried out to search for amastigote forms of the parasite. During the treatment all animals presented remission of symptoms. However, two dogs were observed to present new symptoms in the course of the experiment. At the end of the experiment, the presence of amastigote forms of the parasite was evidenced in five of the seven dogs. This enabled us to conclude that the treatment promoted clinical cure but did not eliminate the parasites completely.  相似文献   
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The influence of long-term fertilization on arbuscular mycorrhizal fungi community composition was investigated. Soil samples were taken from a long-term field experiment which was conducted for 5 years to explore the effect of three treatments: control (non-fertilization), conventional (mineral fertilizers—NPK), and alternative (organic fertilizers—farmyard manure). The highest values of AMF community composition were found in the alternative fertilization system after the thirty year of its utilization. After the thirty year the conventional fertilization system showed lower AMF diversity compared to alternative fertilization system. In conclusion the alternative fertilization system enhanced mycorrhizal effectiveness that contributes to increase wheat growth after a long-term experiment. Our findings also suggest that inputs of organic matter source can change positively the AMF community composition, and these results highlight the importance of considering the long-term effect of mineral and organic fertilizers on the AMF community diversity. Thus, the long-term utilization of an alternative fertilization system with continuous input of organic matter may exploit positive situations of jointly beneficial biotic and abiotic conditions.  相似文献   
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