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31.

Background

Lactating sows in Swedish organic piglet production are commonly group-housed with piglets in a multi-suckling pen within 14 days after farrowing. Nursing behaviour may be disturbed when lactating sows are moved to a new environment and mixed with other sows, as they spend more time fighting with other sows and exploring the new surroundings. This can disrupt the inhibitory effect of suckling on ovarian activity and increase the risk of lactational oestrus, making efficient reproductive management difficult. Therefore this study evaluated aggression and levels of the stress hormone cortisol in lactating sows group-housed together with their piglets at one (W1), two (W2) or three (W3) weeks post farrowing.

Results

There was no significant difference (P > 0.05) between the three management routines (W1, W2, W3) regarding number of attacks initiated or received in the mixed group. After mixing, W2 sows had a lower number of shoulder scratches (P < 0.05) than W3 sows. Among the W3 sows, there was a lower (P < 0.01) cortisol concentration in saliva when sows were group housed compared to when they were individually housed. The cortisol response, measured as variation in cortisol concentration in saliva, was also lower (P < 0.05) in group-housed W3 sows compared with W1 sows.For all management routines, sows already living in the new environment (resident sows) initiated more attacks (P < 0.001) and received fewer attacks (P < 0.01) than sows entering the new environment (intruder sows). Overall, multiparous sows initiated more attacks and received fewer attacks than primiparous sows (P <0.001).

Conclusions

Overall, the results suggest that mixing and group housing sows at three weeks post farrowing is less stressful than mixing and group housing sows at one week post farrowing. The results also indicate that parity and whether a sow is a resident or intruder in the group housing environment may have an effect on aggression levels when sows are group-housed.  相似文献   
32.
Two field studies examined the calving patterns of cows in seasonal dairy herds in the Waikato (Field Study 1) and South Taranaki regions (Field Study 2). The first study examined patterns for cows commencing their second or subsequent lactation in herds which had used an inseminating service during the previous season. The second study included first lactation heifers only in 15 herds where animals had been naturally mated, and in 15 herds in which they had been synchronised and then artifically inseminated at the synchronised oestrus.

The parameters describing calving patterns were based on the date for each herd's planned start of calving (PSC), which was 282 days from the date on which breeding commenced in the preceding season. The average interval from PSC to mean calving date for the 35 herds in Field Study 1 was 22 days, with individual herds anging from 15 to 30 days. In herds with heifers which had been naturally mated (Field Study 2), it was 17.6 days compared to 11.0 days for previously synchronised animals. Calculating the intervals from PSC to median calving date and separately for the last two quartiles more effectively described a herd's calving pattern. The duration for the last quartile of the calving pattern was influenced by the extent and timing of induced calving. In Field Study 1, 88.6% of the 35 herd owners induced premature parturition in at least one cow. In these herds, 11.3% of cows were treated and calved prematurely.

Only 61.7% of heifers which had previously been naturally mated calved by 3 weeks after PSC. Their calving dates were not evenly distributed over this 3-week period, with 9.8% in the first week and 25.6% in the third week. The calving pattern for heifers which had been previously synchronised showed several distinct peaks. Calvings to the synchronised mating were completed 15 days after PSC, by which time 64.7% of animals had calved. By 3 weeks after PSC, 72.9% of these heifers had calved.

The results showed that there was considerable variation in calving patterns in seasonal dairy herds. This variation would have been due to differences in conception pattern, and the way induced calving had been applied. The calving pattern in heifers which had been naturally mated was less concentrated than had been expected. Synchronisation can significantly concentrate the calving pattern of these first lactation animals.

The parameters used to describe calving patterns may be less applicable in herds in which a high proportion of animals is induced to calve prematurely, or where a whole herd is synchronised. Nonetheless, they do serve as an illustrative example of the variation in calving patterns among herds.  相似文献   
33.

Various behavioural, physiological and production-related parameters were examined in 200 adult female pastel and pearl mink either family housed in three-room cages with no weaning or housed singly in one-room cages after normal weaning procedures. Scanning observations of behaviour and use of the cages were performed in the nursing period and several parameters related to reproduction were registered. The adult female mink were weighed when kits were 16 weeks old (September) and again at pelting time (November). Blood samples were collected from all adult female mink in September at which time the teat condition and fur damage were evaluated. After pelting, bite marks on the leather side of the skin were counted, fur damage was graded after severity and the fur size was measured. Some positive consequences of being family housed were revealed. The familyhoused adult female mink showed a lower level of stereotypes and a higher level of defensiveness and curiosity than the adult female mink in one-room cages during the nursing period. In September and November, family-housed adult females were heavier than singly housed adult females. However, most of the physiological or production-related parameters pointed in a negative direction for familyhoused adult female mink. Reproductive success was somewhat reduced, although not significantly. Plasma cortisol levels were elevated in September, indicating higher levels of stress in these females. They showed a generally poor teat condition in September, with a high proportion of swollen or bitten teats. A high proportion of these adult females showed fur damage in both September and November, and a high number of bite marks was found on the leather side of the skins of these females, indicating that family housing had a high cost for the adult female mink. In conclusion, there seem to be some benefits, at least on the behavioural level, in keeping adult female mink in three-room cages during the nursing period, but both physiological and production-related parameters indicated that the welfare of the adult female mink was threatened if she was continuously cohoused with her litter past the normal age of weaning.  相似文献   
34.
The effects of rearing cage type and dietary Ca, available P and vitamin D3 (VitD3) on body and skeletal development were studied. A total of 3,420 Lohmann LSL-Lite day-old chicks were reared in conventional (CON) or furnished cages (FUR) to 16 wk of age. Initially, 40 and 150 chicks/cage were placed in CON and FUR and transitioned to 20 and 75 chicks/cage at 8 wk of age, respectively. Three diets: Diet 1, Diet 1.5 and Diet 2 were formulated to meet nutrient specifications with Diet 1.5 and Diet 2 containing 1.5 and 2 times more Ca, P and VitD3 than Diet 1, respectively. Diets were allocated within cage type to give 6 replicates and fed in 3 feeding programs: starter, grower and developer. At 4, 12 and 16 wk of age, BW was recorded, and femur, tibia and blood samples for bone quality and related parameters. There were no interactions (P > 0.05) of cage type, diet and pullet age on BW, plasma Ca and inorganic P, femur and tibia morphometry, mineral density (MD), breaking strength (BS) and ash concentration (AC). Concentration of Ca, P and VitD3 linearly decreased BW (P < 0.001), relative femur (P = 0.010) and tibia weight (P = 0.013). A quadratic increase on femur MD (P = 0.03) and BS (P = 0.026) was observed with dietary concentration of Ca, P and VitD3. Femur (P = 0.031) was longer for CON than FUR pullets, however, femur for FUR pullets had higher (P = 0.003) AC. Cage had no effect (P ≥ 0.415) femoral MD and BS. Pullets reared in FUR cages exhibited higher tibial MD (P = 0.015), BS (P = 0.071), AC (P < 0.01) and whole-body mineral content (P < 0.01). In conclusion, cage type and diets showed independent effect on femur and tibia quality with FUR pullets exhibiting enhanced indices of mineralization. Feeding pullets twice the recommended Ca, P and VitD3 decreased BW, relative weight of leg bone but enhanced femoral strength with no effects on tibia attributes.  相似文献   
35.
农村宅基地的利用、退出及其补偿是农村宅基地管理制度创新的核心。该研究根据芜湖市农村实地调查数据,分析农户宅基地利用状况及其特点、农户对宅基地产权的认知、农户宅基地流转状况、农户退出宅基地的意愿及其影响因素,提出了农村宅基地综合管控的制度创新建议。  相似文献   
36.
基于吉林省森工林区中的湾沟林业局、三岔子林业局、泉阳林业局(县)的183户职工住户的分层随机抽样问卷结果,描述性分析了吉林省森工林区林场和局址职工居民现住房情况及棚改实施成果。分析结果显示,在林区,人均住房面积和人均住房价值均较小,住房形式主要为楼房,且林场内住户棚改比例大于局址住户,职工对住房的满意度较低。局址家庭财产积累多于林场,更有利于提高住房条件。建议贯彻落实吉林省森工林区棚户区改造政策,加大企业投资,大力发展养殖业,因地制宜地发展经济,提高职工收入,改善家庭住房条件,完善并发展职工住房交易体系。  相似文献   
37.
关于提高农村土木房屋抗震能力的思考   总被引:1,自引:0,他引:1  
曾耀辉 《安徽农业科学》2010,38(16):8809-8810
介绍了农村房屋存在的问题,分析了四川攀枝花——会理地震灾害较为严重的原因,提出了相应的抗震措施,以确保农村土木房屋的抗震能力,保证人们的生命和财产安全。  相似文献   
38.
农村住宅用地合理布局探索   总被引:2,自引:2,他引:0  
冯薇 《河北农业科学》2010,14(2):121-122
土地是最重要的自然资源。就目前而言,我国农村普遍存在不合理利用土地的现象。农村住宅缺乏科学设计,超标占地造成土地的极大浪费。为此,探讨了改善农村住宅用地的措施,并提出了新农村社区2种住宅类型。  相似文献   
39.
针对现在居住区景观绿地设计中的不足之处,通过对居住区室外环境空间的分析,从中国传统居住心理出发,总结出居住区景观绿地中私密性空间运用的必要性及设计手法。  相似文献   
40.
This paper attempts to examine the impacts of the spatial structure of landscape on housing premiums in Austin, TX through the years of 2009–2011. Dissimilar to previous studies, this paper highlighted three points. First, landscape patterns was observed—not only the composition but also the configuration in terms of shape, fragmentation, isolation, and connectivity. Second, the definition of neighborhood in this study was closely matched to the nature of a residential neighborhood, which was represented by a residential subdivision that has a name and a high level of homogeneous characteristics (i.e., development age, appraised value, lot size, and housing size). This approach specifically helps understand the impact of landscape configuration at the micro-level neighborhoods. Third, the hierarchical nature of neighborhoods and embedded parcels—nested parcels within the same neighborhood posit a certain level of identity as a whole—was given attention so that multi-level modeling could be employed. Conceptually and theoretically, multi-level modeling is a better approach to examine phenomenon that occur in multi-level units that show a clear hierarchy. The findings indicated that home buyers are willing to pay more to live in neighborhoods with the high ratio of tree cover. This is a finding consistent with previous studies. Meanwhile, the detailed spatial configuration of landscape does not play an important role at the residential neighborhood level. This result urges policy makers to be more scale-sensitive when planning landscape and indicates that micro neighborhoods are not the correct spatial level to discuss the spatial configuration of landscape, greenways, and green network.  相似文献   
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