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41.
In fish hormones are released into the nutritive yolk sac during oogenesis in quantities that mirror female plasma levels, thus implying a potential for the maternal endocrine state at spawning to affect offspring characteristics. In the present study, mature female Atlantic salmon, Salmo salar, were given intraperitoneal cortisol implants to investigate potential impacts of simulated stress on offspring ontogeny. Maternal cortisol levels reduced fertilization success and affected several offspring characters: lowered initial survival rates, impaired growth early in life and increased prevalence of morphological abnormalities in adult individuals. In addition, offspring from cortisol administered females displayed increased locomotor activity in an acute confinement test. These results suggest that developmental trajectories of salmon offspring can be considerably altered if their mothers experience severe stress during the final stages of gametogenesis. The present findings may have conceptual and applied ramifications as they demonstrate a mechanism that links the maternal environment to subsequent viability of the progeny.  相似文献   
42.
Berug  Ragnar 《Potato Research》1962,5(3):242-251
Potato Research - Storage of freshly dug potato tubers for 2 or 4 hours in bright sunlight resulted in only minor changes in the solanine content. A significant increase in solanine in tubers...  相似文献   
43.
To increase the competitiveness of wood as a building material requires knowledge of which customer needs require attention in terms of quality improvement and/or product development to best satisfy customers. Hence, information as to the impact on customer satisfaction of the fulfillment of different customer needs, as well as the performance of wood and substitutes in providing for these needs, is needed. This article suggests the use of customer satisfaction modeling (CSM) for assessing customer needs. The methodology is evaluated in the context of floorcovering. The results suggest that CSM is well suited for extracting the information necessary for prioritizing customer needs: importance/impact and performance data for attributes as well as for customer benefits. The study indicates the necessity of considering substitute materials not only for performance comparisons; substitutes may also reveal otherwise latent customer needs. Practical, functional, benefits exert the greatest impact on customer satisfaction for wooden flooring as well as its closest substitutes, laminate and carpet. Hygiene and a low cost over the life cycle are apparently the customer benefits that require attention from wooden flooring manufacturers, because importance is high and performance relatively low.  相似文献   
44.
Chronic over‐exposure to diet‐borne copper has been implicated in the development of black stripes caused by melanin deposits (melanosis) around the blood vessels in fillets of farmed Atlantic cod, Gadus morhua L. To test this hypothesis a 6‐mo pilot study using feeds containing controlled amounts of copper has been performed. Cumulative data from each feed group showed that 56% of cod fed a diet containing 10 mg/kg of added copper had black stripe while 58% of cod on a diet containing 5 mg/kg of added copper were affected. Cod on a diet with no added copper had 33% of individuals positive for black stripe, and in a final group on a diet containing no supplementary trace metals and minerals 16% of individuals were affected. Weight gain, increase in length, hepatosomatic index, and condition factor were unaffected by the changes made to mineral supplements. Melanosis has been observed in 24% wild cod of market size (n = 30) whilst 85% of market‐sized farmed cod examined have had black stripe (n = 403).  相似文献   
45.
Summary

Carrots of cv. Panther F1 were grown in climate chambers at 9, 12, 15, 18 and 21°C, constant diurnal temperatures at three different periods of the year. The effect of varying solar radiation and temperatures were evaluated on growth, sensory attributes and chemical composition. Higher levels of light significantly increased most chemical and physical variables of the carrot roots. Temperature was the most important factor determining the variation in sensory and chemical variables, whereas for morphological features like root weight, root length and diameter measurements, light was more important than temperature. Principal component analysis (PCA) of chemical and physical variables explained 85% of the total variation by the first three principal components, the first component (PCI) being defined by physical variables, explained 46% of the variation, while the temperature related PC2 explained 32% of the variation. Prediction of sensory variables by chemical or physical variables by means of partial least square (PLS) was higher at low light intensity than at high light intensity.  相似文献   
46.
Summary Potato tubers of Pimpernel, grown at 18 levels of K or NPK supply, were assessed for enzymic browning and after-cooking discoloration after different treatments. The influence of potassium supply during the previous 30 years and in the year of growing on enzymic browning was pronounced. Enzymic browning of the tubers showed a strong negative correlation with concentration of potassium in tubers and haulm sampled at harvest. A significant, but less strong relationship between tuber colour and potassium in tubers and haulm was found for after-cooking discoloration. An increase in enzymic browing and after-cooking discoloration took place during the first 3 months of storage, but not during the next 3 months. Less enzymic browning occurred after 3 months of storage at 12°C than at 3°C. Storing at 0°C for 3 days in the fall had little affect on enzymic browning, whereas conditioning at 16°C slightly decreased enzymic browning.
Zusammenfassung Aus zwei Langzeit-Feldversuchen wurden 1969 Kartoffelknollenmuster der Sorte Pimpernel gezogen. In diesem Versuch wurden 18 Stufen von K-oder NPK-Gaben verglichen (Tabellen 1 und 2). Die Verf?rbung von rohen und gekochten Knollen (Tabelle 3) wurde beurteilt, und in Knollen-und Krautmustern (Entnahme bei der Ernte) wurde der Kaligehalt bestimmt. Der Einfluss der Kaligabe w?hrend der vorhergehenden 30 Jahre und in Jahre 1969 auf die enzymatische Verf?rbung war deutlich (Abb. 1, Tabelle 4). Wo die Durchschnittsgaben von Kalium in früheren Jahren weniger als 70 kg/ha betrugen, trat eine betr?chtliche Verbesserung in der Farbe ein, wenn die Gabe im Anbaujahr von 100 auf 200 kg/ha erh?ht wurde (Abb. 2). Die Farbe der rohen Knollen war jedoch selbst bei einer Düngung mit 200 kg/ha unbefriedigend bei Parzellen, bei denen in früheren Jahren die Kaliversorgung im Boden auf einem tiefen Stand war. Die Verf?rbung nach dem Kochen war weniger ausgepr?gt und weniger beeinflusst durch die Kaligabe als die enzymatische Braunverf?rbung (Tabelle 4). Der Kaligehalt in % in Knollen und Kraut (Musterentnahme bei der Ernte) war in enger Beziehung zu der enzymatischen Braunverf?rbung, und es bestand eine signifikante, aber weniger enge Korrelation mit der Verf?rbung nach dem Kochen (Abb. 3 und 4). Die Braunverf?rbung der rohen Knollen und die Verf?rbung nach dem Kochen nahmen in den drei ersten Monaten der Lagerung zu, aber nicht w?hrend der drei folgenden Monate. Die Rohverf?rbung war nach einer dreimonatigen Lagerung bei 12°C schw?cher als bei 3°C. Setzte man Knollen für drei Tage im Herbst einer Temperatur von 0°C aus, so hatte dies wenig Einfluss auf die Rohverf?rbung (Tabelle 4). Konditionierung w?hrend 7 Tagen bei 16°C verbesserte die Farbe der rohen Knollen leicht (Tabelle 5). Die Ergebnisse umfassen vor allem die Stufen unter der optimalen Kaligabe. Ein Ueberschuss an Kali wurde wahrscheinlich nicht erreicht.

Résumé On a prélevé, en 1969, des échantillons de tubercules de pomme de terre, variété Pimpernel, dans des essais en champ de longue durée, dans lesquels ont été comparés 18 doses de K ou de NPK (tableaux 1 et 2). On a établi la décoloration sur les tubercules crus et cuits (tableau 3), et on a déterminé le potassium dans les tubercules et les tiges échantillonnés à la récolte. L'influence de l'approt de potassium au cours des trente années antérieures et au cours de la dernière année (1969) sur le brunissement enzymatique est prononcée (fig. 1, tableau 4). Là où les doses moyennes de potassium au cours des années précédentes sont inférieures à 70 kg/ha, il appara?t une amélioration considérable dans la couleur lorsque l'apport de potasse, lors de la dernière végétation, atteint 100 à 200 kg/ha (fig. 2). Cependant la couleur des tubercules crus n'est pas satisfaisante, même apr⪻s une fumure de 200 kg/ha sur les parcelles où le potassium du sol a été maintenu à un niveau bas pendant les années précédentes. Après cuisson, l'altération de la couleur est moins grave et moins influencée par l'approt potassique que le brunissement enzymatique (tableau 4). Le pourcentage de potassium dans les tubercules et les tiges, échantillonnés à la récolte, montrent une relation étroite avec le brunissement enzymatique, et une corrélation significative moins étroite avec la décoloration aprés cuisson (fig. 3 et 4). Le brunissement enzymatique et la décoloration après cuisson augmentent au cours des trois premiers mois de conservation, mais non pas durant les trois derniers mois. Il appara?t moíns de brunissement enzymatique après trois mois de conservation à 12°C plut?t qu'à 3°C. Soumettre brusquement les tubercules à 0°C pendant trois jours a peu d'effet sur le brunissement enzymatique (tableau 4). Le fait de placer les tubercules pendant 7 jours à 16°C améliore légèrement la couleur des tubercules crus (tableau 5). Les résultats se rapportent le plus exactement aux niveaux situés en-dessous de l'apport optimum de potassium. On n'a probablement pas atteint l'excès de potassium.
  相似文献   
47.
The effects of addition of evening primrose oil (EPO) to a mink diet in the breeding season on the reproductive performance and kit and female performance during the lactation period were investigated in an experiment with 4 groups of male and female mink. Matings were carried out so that control males were mated to both control and supplemented females. Similarly, supplemented males mated both control and supplemented females. Reproductive results were evaluated both on a group basis and as an effect of male or female treatment, respectively. After males supplemented with EPO, there was a tendency for reduced rate of stillborn kits and kit losses during the first 21 days of life. These effects could not be explained physiologically. Female treatment did not affect reproductive performance, but there was a tendency for lower weight losses during lactation for EPO-supplemented females. Kit performance during the lactation period was independent of experimental treatment.  相似文献   
48.
In an experiment including 2400 layers, a diet with 40% whole oats incorporated into 3 mm pellets (experimental diet) was compared with a complete diet, also as 3 mm pellets, but containing no whole oats (control diet). These diets were examined in conventional 3-hens cages and two furnished cage systems with 8 or 16 birds per group including nest, perches and litter. The effects of diet, rearing condition and cage system on performance, plumage condition, comb lesions and rear body wounds were studied. Furthermore, the effect of feed structure on gizzard characteristics and interactions with access to litter during rearing and laying periods were examined. The hybrids LSL and Shaver 2000 were included in the experiment. Egg production was lower (P<0.05) in furnished cages than in conventional cages. No difference in plumage condition was found between diets, but a significantly poorer plumage condition (P<0.05) was observed with increasing group size. Also, the frequencies of rear body (P<0.05) wounds increased as the group sizes increased, while no such effect was observed for comb lesions. Higher (P<0.05) feed consumption was observed in furnished cages than in the conventional, causing a corresponding increase (P<0.05) in feed conversion rate (FCR). Higher (P<0.05) FCR was observed for birds fed pellets with whole oats than the control. Whole oats also increased (P<0.05) the weight of gizzard and gizzard contents. For LSL, better (P<0.05) plumage condition was found for birds reared on a deep litter floor compared to cage rearing. It was concluded that no beneficial effect of replacing high amounts of ground oats with whole oats was observed. Genotype and rearing method may interact with housing system.  相似文献   
49.
Abstract

In two experiments, a total of 4346 laying hens housed in battery cages, with three hens per cage (C), and in two aviary systems, both with tiered wire floors and litter (Lövsta with two tiers (L) and Marielund with three tiers (M)), were used for studies on production, egg quality, health, plumage and foot condition, bone strength and bird location. Three hybrids were used: Lohmann Selected Leghorn (LSL) were kept in all three systems, Dekalb XL (DK) were kept in both aviaries and Lohmann Brown (LB) in M only. Production and feed conversion in M were inferior but not significantly different from C but significantly better than in L. Proportions of dirty eggs were significantly higher in the avaries. No significant differences were found in interior egg quality traits between keeping systems. LSL showed higher production and better feed conversion than the other hybrids and a tendency for a lower proportion of mislaid eggs. Mortality varied considerably between the aviary pens, reaching 35% in LB mainly owing to cannibalism and salpingitis. Keel bone lesions and bumble foot appeared in the aviaries, while toe pad hyperkeratosis was observed in C. Hens in aviaries had significantly stronger bones (tibia and humerus) and showed more wounds from pecks, inferior plumage condition and dirtier feet than in C. LSL had more bumble foot injuries than LB but better plumage condition than DK. The birds used the different parts in the aviaries well, especially the perches on the resting top tier during the night.  相似文献   
50.
Abstract

Vitamin B12 supplementation in the prevention of feed-induced iron deficiency anaemia was evaluated with six treatment groups of mink kits, comprising a control group and five groups fed an anaemiogenic diet either unsupplemented, supplemented with vitamin B12 orally, or by intramuscular injection, with iron therapy by ferrous fumarate and cysteine, and iron therapy plus vitamin B12 orally. Unsupplemented animals showed symptoms of anaemia including poor growth performance, achromotrichia and poor fur quality. Oral vitamin B12 supplementation, but not injections, had some effect in preventing anaemia, indicating an influence on intestinal iron absorption. Iron therapy completely prevented the occurrence of anaemia, and simultaneous addition of vitamin B12 had no further positive effect.  相似文献   
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