全文获取类型
收费全文 | 63篇 |
免费 | 18篇 |
专业分类
林业 | 5篇 |
8篇 | |
综合类 | 4篇 |
农作物 | 1篇 |
水产渔业 | 6篇 |
畜牧兽医 | 56篇 |
植物保护 | 1篇 |
出版年
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 5篇 |
2013年 | 6篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 5篇 |
2002年 | 3篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有81条查询结果,搜索用时 31 毫秒
1.
A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management
下载免费PDF全文
![点击此处可从《Australian veterinary journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Objectives
To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendationsMethods
A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.Results
The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.Conclusion
The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.2.
1. The composition of 106 vitamin supplements used in about 85% of the Spanish poultry production diets were studied. Vitamin supplements were grouped by production classes and, for broilers and pullets, also by feeding periods. 2. Four vitamins (niacin, alpha-tocopherol, pantothenic acid, and riboflavin) comprised over 87% of the vitamin supplements by weight (choline excluded), whereas alpha-tocopherol and retinol represented from 51% to 60% of the total vitamin cost. 3. The highest and lowest vitamin supplementation rates were for broilers in the starter and withdrawal periods (106 and 44 mg/kg, respectively) and the mean values for breeders, pullets and layers were 104, 58, and 48 mg/kg, respectively. 4. Supplements with higher vitamin contents showed less variability in their composition. Retinol, cholecalciferol, riboflavin and pantothenic acid showed the lowest variability within supplements (6% to 36% CV), whereas alpha-tocopherol, menadione, thiamin and biotin showed the highest (40% to 224% CV). 5. Vitamin supplementation rates were compared with requirements, taking into account the dietary contribution. In general, vitamin fortification exceeded the NRC recommendations, using a high safety margin for some vitamins such as vitamin A (from 2.6 to 7.8) and for some poultry classes such as breeders (3.2). 相似文献
3.
EFFECTS OF FLUID AND COMPUTED TOMOGRAPHIC TECHNICAL FACTORS ON CONSPICUITY OF CANINE AND FELINE NASAL TURBINATES
下载免费PDF全文
![点击此处可从《Veterinary radiology & ultrasound》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Raimonda Uosyte Darren J. Shaw Danielle A. Gunn‐Moore Eduardo Fraga‐Manteiga Tobias Schwarz 《Veterinary radiology & ultrasound》2015,56(5):494-502
Turbinate destruction is an important diagnostic criterion in canine and feline nasal computed tomography (CT). However decreased turbinate visibility may also be caused by technical CT settings and nasal fluid. The purpose of this experimental, crossover study was to determine whether fluid reduces conspicuity of canine and feline nasal turbinates in CT and if so, whether CT settings can maximize conspicuity. Three canine and three feline cadaver heads were used. Nasal slabs were CT‐scanned before and after submerging them in a water bath; using sequential, helical, and ultrahigh resolution modes; with images in low, medium, and high frequency image reconstruction kernels; and with application of additional posterior fossa optimization and high contrast enhancing filters. Visible turbinate length was measured by a single observer using manual tracing. Nasal density heterogeneity was measured using the standard deviation (SD) of mean nasal density from a region of interest in each nasal cavity. Linear mixed‐effect models using the R package ‘nlme’, multivariable models and standard post hoc Tukey pair‐wise comparisons were performed to investigate the effect of several variables (nasal content, scanning mode, image reconstruction kernel, application of post reconstruction filters) on measured visible total turbinate length and SD of mean nasal density. All canine and feline water‐filled nasal slabs showed significantly decreased visibility of nasal turbinates (P < 0.001). High frequency kernels provided the best turbinate visibility and highest SD of aerated nasal slabs, whereas medium frequency kernels were optimal for water‐filled nasal slabs. Scanning mode and filter application had no effect on turbinate visibility. 相似文献
4.
Morphometry,Morphology and Ultrastructure of Ring‐tailed Coati Sperm (Nasua nasua Linnaeus, 1766)
下载免费PDF全文
![点击此处可从《Reproduction in domestic animals》网站下载免费的PDF全文](/ch/ext_images/free.gif)
HVR Silva FF Magalhães LR Ribeiro ALP Souza CIA Freitas MF de Oliveira AR Silva LDM Silva 《Reproduction in domestic animals》2015,50(6):945-951
The ring‐tailed coati (Nasua nasua) is a procyonid whose population is in sharp decline. Therefore, studies are needed to better understand the reproduction of this animal. For this reason, this study aimed to evaluate the morphology, morphometry and sperm ultrastructure of ring‐tailed coati sperm. Four captive adult males were used for this study. Slides stained with Bengal Rose were used for the morphometric and morphologic analyses. The length and width of the head were measured, as well as the length of the midpiece and tail and the total length of the sperm. Scanning electron microscopy and transmission electron microscopy were used for the ultrastructural analyses. The most obvious morphological abnormalities observed were coiled tails (6.1 ± 8.7%) and the lack of acrosomes (5.4 ± 4.4%). Regarding the morphometry, the measurements of the head (length × width), midpiece (length) and tail (length) were (mean ± SD) 6.2 ± 0.4 × 8.1 ± 0.6 μm, 14.1 ± 0.5 and 63.9 ± 4.1 μm, respectively, and the total length of the sperm was 86.1 ± 4.3 μm. Through electron microscopy, the presence of electron‐lucent points in the nucleus and the presence of approximately 55 mitochondrial spirals in the midpiece were identified. The data obtained in this study provide detailed information on the sperm characteristics of coatis and may inform future research on germplasm conservation, both for this species and other threatened procyonids. 相似文献
5.
The effect of footrot on body weight and wool growth of sheep 总被引:1,自引:0,他引:1
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured. 相似文献
6.
Diterpenes from Salvia broussonetii transformed roots and their insecticidal activity 总被引:2,自引:0,他引:2
Fraga BM Díaz CE Guadaño A González-Coloma A 《Journal of agricultural and food chemistry》2005,53(13):5200-5206
The new diterpenes brussonol (1) and iguestol (6alpha,11-dihydroxy-12-methoxy-abieta-8,11,13-triene) (2) with an icetexane and a dehydroabietane skeleton, respectively, have been isolated from hairy root cultures of Salvia broussonetii. Other previously known diterpenes, 7-oxodehydroabietane, 11-hydroxy-12-methoxyabietatriene, taxodione, inuroyleanol, ferruginol, deoxocarnosol 12-methyl ether, cryptojaponol, pisiferal, sugiol, isomanool, 14-deoxycoleon U, 6alpha-hydroxydemethylcryptojaponol, demethylsalvicanol, and demethylcryptojaponol, were also obtained from these roots. The insect antifeedant and toxic effects of several of these compounds were investigated against the insect pests Spodoptera littoralis and Leptinotarsa decemlineata. Additionally, their comparative cytotoxic effects were tested on insect Sf9 and mammalian CHO cells. Demethylsalvicanol (4) was a moderate antifeedant to L. decemlineata, whereas brussonol (1) was inactive. 14-Deoxycoleon U (15) was the strongest antifeedant, whereas demethylcryptojaponol (11) was toxic to this insect. None of these compounds had antifeedant or negative effects on S. littoralis ingestion or weight gains after oral administration. Demethylcryptojaponol (11) was cytotoxic to mammalian CHO and insect Sf9 cell lines, followed by the icetexane derivative brussonol (1), with moderate cytotoxicity in both cases. The remainder of the test compounds showed a strong selective cytotoxicty to insect Sf9 cells, with demethylsalvicanol (4) being the most active. 相似文献
7.
The local effects of isolated magnetic adatoms on the electronic properties of the surface of a superconductor were studied with a low-temperature scanning tunneling microscope. Tunneling spectra obtained near magnetic adsorbates reveal the presence of excitations within the superconductor's energy gap that can be detected over a few atomic diameters around the impurity at the surface. These excitations are locally asymmetric with respect to tunneling of electrons and holes. A model calculation based on the Bogoliubov-de Gennes equations can be used to understand the details of the local tunneling spectra. 相似文献
8.
Joanna Hedley Livia Benato Gemma Fraga Christopher Palgrave Kevin Eatwell 《Journal of Exotic Pet Medicine》2013,22(2):212-217
A 2.5-year-old male African pygmy hedgehog (Atelerix albiventris) was presented with a 2-week history of lethargy, reduced appetite, and general weakness. Based on the clinical signs and heart valve abnormalities observed during an echocardiography examination, a provisional diagnosis of endocardiosis or endocarditis was made. Immediate therapeutic intervention consisted of furosemide, pimobendan, and amoxicillin/clavulanate. Despite medical treatment, 2 weeks following presentation, the hedgehog’s physical condition deteriorated to the point that euthanasia was recommended for the patient and agreed to by its owner. A postmortem examination was performed and tissue samples submitted for histopathology revealed a final diagnosis of valvular endocardiosis and wobbly hedgehog syndrome. 相似文献
9.
10.
Taciana MF Silva Roberio G Olinda Carla MF Rodrigues Ant?nio CL Camara Francisco C Lopes Wesley AC Coelho Múcio FB Ribeiro Carlos IA Freitas Marta MG Teixeira Jael S Batista 《Veterinary research》2013,44(1):1
The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes. 相似文献