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The objectives of this paper were to characterise lesions found at the hock and to establish their prevalence across a large sample of dairy cows in the UK. In addition, the study aimed to examine farmers' perceptions of these lesions. Seventy-seven farms were visited; both hocks on a random sample of approximately 50 cows were scored on a categorical scale for hair loss, ulceration and swelling. In addition, the size and location of lesions were marked on a hock map. A questionnaire designed to explore attitudes towards lesions was conducted with the owner. Hair loss and ulceration were seen at five locations. Hair loss was identified on 5,619 of 6,896 hocks (mild: 43.7 per cent; moderate: 25.1 per cent; severe: 12.6 per cent) and 1,137 of 6,896 hocks had areas of ulceration (mild: 8.6 per cent; moderate: 5.8 per cent; severe: 2.1 per cent). The majority of lesions were small; however, a small proportion had extensive areas of hair loss (maximum size 113.3 cm2) and ulceration (maximum size 95.5 cm2). Moderate swelling was recorded on 20 per cent of hocks, and 2.0 per cent had severe swelling. Interview results suggested that more than 90 per cent of participants were aware of hock lesions and a third had sought treatment for them; most felt that lesions had at least some impact on productivity and welfare.  相似文献   
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The aim of this study was to evaluate the effects of thyroxine administration on morphometric parameters, expression of vascular endothelial growth factor (VEGF) and vascularization in the uterus and placenta and reproductive parameters in gilts at 70 days of gestation. At 150 days of age, i.e., before first heat, 20 gilts were randomly divided into two experimental groups: treated (n = 10) and control (n = 10). The treated group received a daily dose of 400 μg of l ‐thyroxine (T4) in their diet until slaughter and the control group received only typical meals. Before artificial insemination, blood was collected to determine plasma total T4. The gilts were inseminated in the second oestrus and slaughtered at 70 days of gestation. The foetal thyroid follicular epithelium height, number, size and weight of foetuses; foetal myogenesis, corpora lutea number, embryonic mortality rate, uterine weight, placental weight and placental fluid volume were measured. Histomorphometric and immunohistochemical analysis of uterus and placenta were determined. The averages of all variables were compared by the Student’s t‐test. The gilts treated with thyroxine showed significant increase of plasma total T4. At 70 days of gestation, the heights of the trophoblastic epithelium, endometrial epithelium and endometrial gland epithelium were significantly higher in the group treated with T4. The expression of cytoplasmatic and nuclear VEGF in trophoblastic cells and the number of blood vessels per field in endometrial stroma were significantly higher in the gilts treated with T4. No other significant differences between groups were obtained with respect to other parameters (p > 0.05). We conclude that oral administration of T4 up to 70 days of pregnancy in gilts affects the morphometric parameters, the expression of placental VEGF and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation.  相似文献   
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The California mastitis test (CMT) is used on farms to identify subclinical mastitis by an indirect estimation of the somatic cell count (SCC) in milk. Four commercially available detergents were compared with a bespoke cmt fluid for their ability to detect milk samples with a scc above 200,000 cells/ml; differences between the interpretation of the results of the tests by eight operators were also investigated. The sensitivity and specificity of the test were affected by the type of detergent, and by the operators' interpretations. When used by the most sensitive operator, suitably diluted Fairy Liquid performed almost identically to cmt fluid in identifying milk samples with more than 200,000 cells/ml. The average sensitivities achieved by the eight operators for detecting this threshold were 82 per cent for Fairy Liquid and 84 per cent for cmt fluid, and the specificities were 93 and 91 per cent respectively. The other detergents contained less anionic surfactants and were less sensitive but similarly specific.  相似文献   
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Pruned triple-row hedges ofGrevillea robusta with 11 rows of maize planted in parallel on either side were grown in 12.5×16.0 m plots on a flat, freely exposed site. There were two replicates of four orientation treatments and crop yield was recorded row-by-row over 9 seasons. After the hedges had become established there were some marked differences in maize yields between sides, especially in the first rainy seasons. The maize on the downside of prevailing winds frequently showed improved growth and yield over the non-sheltered maize, sometimes by as much as 50% over the whole subplot and up to 80% in the tree/crop interface zone. These differences were significant (p0.05) when analyzing the whole experimental period for first and for second rainy seasons separately (prevailing winds more southerly or northerly, respectively), although they varied between seasons and zones. Attributing results to shelter can only be adduced circumstantially because meteorological data were not collected at the plot level. Shading effect were not considered important over the whole sub-plot. Soil water profiles obtained from an array of gypsum resistance blocks in two of the plots (at 000° and 090°) characterized the wetting and drying patterns in this system, but expected asymmetries due to orientation effects were not apparent except, perhaps, fleetingly in the topsoil. At the end of the experiment the distribution of fine roots of both species was examined by means of root trenching. TheG. robusta root system extended almost symmetrically to the edges of the plot in the uncropped part, but only to some 4 m from either side of the hedge where cropped. Part of the upper profile to 1.3 m was shared with the maize roots, butGrevillea rooted further down to at least 2 m. as well as rooting deeper. The possible implications of such niche differentiation for below-ground resource capture are noted.  相似文献   
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A questionnaire to examine the attitudes and perceptions of cattle practitioners to pain in cattle was sent to 2398 practitioners working in the UK, and 641 responses were received. From the range of procedures and conditions outlined in the questionnaire, claw amputation was scored as the most painful procedure undergone by adult cattle (assuming no analgesic drugs were administered), and neck calluses were scored as the least painful condition experienced by adult cattle. The pain associated with dystocia was considered the least painful experience for calves, and fracture of a distal limb and surgery for an umbilical hernia equally the most painful. There were significant differences between the pain scores assigned by men and women and by respondents who had graduated in different decades; female respondents and more recent graduates tended to give a higher pain score for most conditions. There were also significant differences between the pain scores assigned by respondents who routinely used analgesics and those who did not, the latter being more likely to assign significantly lower pain scores.  相似文献   
50.
AIMS: To quantify the range of attitudes and perceptions of cattle practitioners to painful procedures and conditions in cattle, to identify some of the demographic factors affecting those attitudes and perceptions, and to compare results from veterinarians based in New Zealand with those from the United Kingdom (UK) and Europe.

METHODS: A questionnaire, based on one used for similar surveys in Europe, was sent to all 455 members of the Society of Dairy Cattle Veterinarians (DCV) of the New Zealand Veterinary Association. This questionnaire included a section on demographic data, e.g. gender, year of graduation, and preveterinary school background, and a section which asked the respondents to rate on a scale of 1 to 10 how painful they thought 24 procedures and conditions would be without any analgesia.

RESULTS: A total of 166 questionnaires were returned, a response rate of 37%. From the range of procedures and conditions outlined in the questionnaire, those perceived as most painful were claw amputation, then Caesarean section, followed by surgery for left-displaced abomasum (LDA). The two least painful were mastitis with milk clots only, and the effect on a calf of dystocia.

There were significant differences between the pain scores assigned by men and women and by respondents who had graduated in different decades. Female respondents and more recent graduates tended to give a higher pain score for most conditions. These effects remained, even after the potential interaction between age and gender had been assessed. The effect on pain score of either background or time spent treating cattle was much less marked than the effect of age and gender.

Overall, the results were very similar to results from similar surveys undertaken in the UK and Europe.

CONCLUSIONS: The responses to this survey indicate that, as in the UK and Europe, dairy cattle practitioners in New Zealand have a wide range of attitudes to pain in cattle. The estimates of the severity of pain were subjective, but such a survey allows the majority opinion of a considerable number of informed assessors to be quantified.

CLINCAL RELEVANCE: The wide range of results suggests that more needs to be done to disseminate up-to-date knowl- edge of pain in cattle to veterinarians to ensure they provide appropriate levels of analgesia. In particular, the baseline data from this study can be used by practitioners to identify whether they are underestimating pain in cattle and, if they are, to assess whether they are using analgesia appropriately. Additionally, this dataset provides an informed and independent assessment of the pain associated with husbandry procedures, and could be used to better guide legislation concerning pain control of such procedures.  相似文献   
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