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81.
The effect of protein/energy ratio and protein level on utilization of protein and energy as indicated by oxygen consumption and ammonia production was investigated. When protein/energy ratio of the diet was optimum, there was no significant increase in ammonia production, indicating no increase in catabolism of protein for energy as protein levels increased. However, when the protein/ energy level was below optimum, there was a significant ( P < 0.05) increase in ammonia production as protein increased, indicating increased catabolism of protein for energy. However, there was no significant increase in oxygen consumption rate.  相似文献   
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A field survey involving 109 horses in 9 stables at a Detroit racetrack was conducted to determine feeding practices and to estimate crude protein (CP), digestible energy (DE), and dry matter (DM) consumption by racing Thoroughbreds, and to compare those intakes with 1989 recommendations of the National Research Council (NRC), "Nutrient Requirements of Horses." Trainers were interviewed regarding: 1) the age and sex of the homes; 2) their feeding practices; and 3) the horse's training and racing schedule. Only adult homes who were actively racing and continuously stabled at the track were included. Body weights (BW) were estimated using a chest girth measurement. The horses had an overall mean body condition score of 5 which indicated average body condition for a racing. Thoroughbred at this track. Feed samples of hay and concentrate from each stable were weighed and analyzed at a commercial laboratory to determine CP, DM, acid detergent fiber (ADF), and estimated energy density. A computer program calculated CP, DE, and DM values for each horse's ration based onamounts fed. The software program included with the 1989 NRC publication was used to compare estimated nutrient intakes with current NRC recommendations for a horse of a given BW. Trainers fed a variety of hays. Eight trainers fed oats and only one fed corn. All trainers fed commercial sweet feeds. The mean total amount of feed for all homes on an "as fed" basis was 13.7 kg. The mean estimated DM intake for all horses was 12.3 kg vs. NRC recommended 11.6 kg. The mean for percentage of roughage in the ration for all stables was 53% vs. a NRC recommendation of 35%. The mean CP% ona DM basis for all stables' rations was 13.8% vs. a NRC recommendation of 11.4%. The means for actual CP and DE intakes for all horses were 1678 g and 33.3 Meal compared with current NRC recommendations of 1324 g CP and 33.1 Meal DE. Protein amounts were above those recommended due to the common practice of feeding relatively higher CP% in the rations than necessary for racehorse performance. These data appear to be more consistent with the recommendations of NRC in 1989 than previous recommendations in 1978.  相似文献   
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Objective: To describe the clinical consequences following ingestion by a dog of a moxidectin‐containing equine deworming product. Few reports exist concerning the treatment and outcome of severe moxidectin toxicity. Treatment, known factors influencing intoxication, and prognosis are reviewed. Case summary: A 10‐month‐old female Border Collie ingested an unknown quantity of a moxidectin‐containing equine deworming product several hours before presentation. Severe neurological signs subsequently developed and included: ataxia, seizures, coma, and respiratory failure. The dog was treated with supportive care including intravenous fluids, activated charcoal, and positive pressure ventilation. Normal spontaneous respiration returned in 34 hours and the patient was discharged 58 hours after ingestion. Full recovery occurred within 1 week of intoxication. New information provided: This report describes moxidectin intoxication and associated respiratory failure in a dog that required mechanical ventilation. The dog's recovery was rapid. Despite severity of signs, the prognosis for patients with moxidectin intoxication is good with appropriate supportive care.  相似文献   
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REASON FOR PERFORMING STUDY: Dental disorders have recently been recognised as having major clinical and welfare implications in donkeys. However, no investigation appears to have examined the association of dental disorders with managemental factors and any intercurrent illness. OBJECTIVES: To determine the association of dental disorders observed in a post mortem study with age group, body condition score, time since last dental treatment, feeding and the illness that necessitated euthanasia or caused death. METHODS: A prospective study documented the type and prevalence of dental disorders in 349 mainly aged donkeys (median estimated age of 31 years) that were subjected to euthanasia over an 18 month period in 2005'Aì2006. The estimated age, body condition score, supplemental feed status, time since last dental treatment and nature of the intercurrent disease that necessitated euthanasia or caused death were also recorded. Multivariable analysis was performed to examine associations of these factors with specific dental disorders and between specific dental disorders. RESULTS: There was a high prevalence (93.4%) of significant dental disease. Age group was significantly associated with the presence of dental disorders and an older age range was a high risk factor for the presence of cheek teeth (CT) diastemata. There was a significant association between the presence of CT diastemata and the concurrent presence of displaced, missing and worn CT. There was also a significant association between the presence of diastemata and colic. CONCLUSIONS AND POTENTIAL RELEVANCE: Aged donkeys have a high prevalence of dental disorders especially of CT diastemata. Dental disorders and, in particular, the presence of CT diastemata were significantly associated with colic. Routine, prophylactic dental treatments should be performed, especially in aged donkeys.  相似文献   
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Sympatric diversification in Lake Trout is generally linked to differences in habitat use (especially depth) as a result of foraging on different prey items. However, extensive sympatric divergence has taken place in the shallow waters (≤30 m) of Great Bear Lake, with multiple Lake Trout morphs varying in head and fin characteristics. To investigate diet partitioning as a potential explanatory mechanism for this diversification, we assessed trophic characteristics and relationships among four sympatric shallow‐water morphs of Lake Trout via analyses of fatty acids and stomach contents. Fatty acids and stomach contents both identified Lake Trout, Cisco and Mysis as key prey items in Lake Trout diets. Interestingly, terrestrial invertebrates were also seasonally important among morphs, reflecting temporal variability of available prey in this arctic lake. Some diet partitioning was observed among morphs; Morph 1 was characterised as a generalist, Morph 3 was more benthic‐oriented, and Morphs 2 and 4 were mainly pelagic feeders. Of the latter, Morph 4 was the most specialised, whereas Morph 2 exhibited alternative feeding tactics of benthic cannibalistic and pelagic piscivorous feeding. Our findings demonstrate that complementary dietary methods can elucidate habits of opportunistic feeders, a task that can often be problematic, given their complex and variable diets. Our results add new information and perspectives on the current model of Lake Trout differentiation, demonstrating niche partitioning based on benthic versus pelagic habitat use and generalist versus specialist feeding tactics.  相似文献   
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