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111.
Karin Hultin Jäderlund DVM Kerstin Hansson DVM Anna-Lena Berg DVM pHd Anders Sjöström MD pHd Kristina Narfström DVM PHD 《Veterinary radiology & ultrasound》2003,44(5):581-588
To evaluate the age of fontanelle closure of normal kittens and the size of their lateral ventricles, 50 ultrasonographic examinations using the bregmatic fontanelle as an acoustic window were made. Seven kittens, laboratory animals, were included in the study. To verify the location of the lateral ventricle, two of the kittens were sacrificed as neonates. In one of them ink was injected prior to autopsy into one lateral ventricle under sonographic guidance. In a longitudinal study of five of the kittens, the skull depth and the depth of the central part of the lateral ventricle reproduced in a longitudinal view could be measured up to the age of about 5 months. During that period, the skull depth increased from a median value of 1.95 cm (1.92-1.98) in a seven-day-old cat to 2.58 cm (2.52-2.59) in a 154-day-old cat, while the afore-mentioned ventricle values increased from 0.3 mm to 1.1 mm. 相似文献
112.
After years of decline and neglect, low woodland types based on coppice management experience renewed interest. Substantial research has demonstrated the potentials of coppice for biomass production and for nature conservation, and coppices are increasingly being suggested for urban situations. Yet, our understanding of the more social aspects of coppice woodlands in modern urban situations is limited. Against this background, this contribution classifies coppice management systems as a basis for identification of social aspects of coppices and their potential use in contemporary urban forestry. Based on this classification, the social perspectives and potential niches for urban coppices are discussed, while lines of research are suggested which will support the development of a thorough and up-to-date knowledge base, against which the social merits of urban coppice woodlands can be critically evaluated. 相似文献
113.
Scholl A Stohr J Luning J Seo JW Fompeyrine J Siegwart H Locquet J Nolting F Anders S Fullerton EE Scheinfein MR Padmore HA 《Science (New York, N.Y.)》2000,287(5455):1014-1016
Antiferromagnetic domains in an epitaxial thin film, LaFeO(3) on SrTiO(3)(100), were observed using a high-spatial-resolution photoelectron emission microscope with contrast generated by the large x-ray magnetic linear dichroism effect at the multiplet-split L edge of Fe. The antiferromagnetic domains are linked to 90 degrees twinned crystallographic regions in the film. The Neel temperature of the thin film is reduced by 70 kelvin relative to the bulk material, and this reduction is attributed to epitaxial strain. These studies open the door for a microscopic understanding of the magnetic coupling across antiferromagnetic-ferromagnetic interfaces. 相似文献
114.
P Wallgren T Segall A Pedersen M?rner A Gunnarsson 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(4):249-260
SPF pigs aged 10 weeks were infected intranasally with Actinobacillus pleuropneumoniae serotype 2. After the onset of clinical symptoms of respiratory disease, which occurred 20 h post-infection, parenteral treatment with ceftiofur, danofloxacin, enrofloxacin, penicillin or tiamulin was initiated (n = 8 per group). Untreated groups, of which one was infected, served as controls. The uninfected control group did not show any signs of disease, while the infected control group was severely affected by the infection and also expressed a decreased weight gain following the challenge. Based on clinical signs, the magnitude of pathological lesions in the respiratory tract found at necropsy performed 17 days post-infection and the number of reisolates of A. pleuropneumoniae made at necropsy, treatments with the quinolones (danofloxacin and enrofloxacin) and the cephalosporine (ceftiofur) were superior to those with penicillin and tiamulin. The latter groups also developed antibodies to A. pleuropneumoniae to a larger extent. Some of the pigs treated with ceftiofur and danofloxacin developed antibodies to A. pleuropneumoniae, and the microbe was reisolated from approximately 50% of these animals. In contrast, pigs treated with enrofloxacin did not develop antibodies to A. pleuropneumoniae, and the challenge strain was not found at necropsy. The performance with respect to daily weight gain and feed conversion corresponded well with the clinical signs developed and the findings made at necropsy. The decreased growth recorded during the acute phase of the disease was, to a large extent, caused by a reduced feed intake. 相似文献
115.
1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (P<0-001). Furthermore, early access to perches decreased the prevalence of cloacal cannibalism during the production period, odds ratio 0-46 (P=0.03). 5. No other factor had a significant effect in these models. Although it was not significant, early access to litter had a non-significant tendency to reduce the prevalence of feather pecking. 相似文献
116.
Bj 《国外畜牧学(猪与禽)》2007,27(3):57-60
3海鸥和燕鸥中的流感病毒1961年,首次报道从燕鸥(sterna hirundo)中分离到流感病毒。该高致病性禽流感H5N3亚型病毒引起了南部非洲禽流感的爆发,并至少造成1300只 相似文献
117.
Liselotte Rothmann Norup Tina S. Dalgaard Janne Pleidrup Anders Permin Torben W. Schou Gregers Jungersen Dorte R. Fink Helle R. Juul-Madsen 《Veterinary parasitology》2013,191(1-2):187-190
Increasingly large numbers of poultry are held in production systems with access to outdoor areas. In these systems intestinal helminths are found with flock prevalences of up to 100%. Helminth infections influence chicken health negatively, which is why the following investigation has been performed.In the present experiment, 20 chickens of two inbred chicken lines containing the major histocompatibility complex (MHC) haplotypes, B14 and R5, were inoculated with 500 embryonated Ascaridia galli eggs. The A. galli-specific IgG titres of serum samples and the excretion of A. galli eggs in chicken faeces were measured for a period of 81 weeks.The level of excreted A. galli eggs measured as eggs per gram chicken faeces (EPG) varied greatly between chickens in each line. Significant differences were found between the two lines and with the R5 chickens reaching the highest levels. Likewise, the A. galli-specific IgG titres in serum differed significantly between the two lines, and an inverse relationship between infection level (EPG) and antibody titres was found. Although this inverse relationship suggests that humoral immunity may be involved in protection against A. galli infection, the high antibody titres did not prevent continued infection. 相似文献
118.
Jesper Møller Nielsen Mats H. Troedsson Morten Rønn Pedersen Anders Miki Bojesen Henrik Lehn-Jensen Walter W. Zent 《Journal of Equine Veterinary Science》2010
The objective of this study was to compare results from endometrial cytological and bacteriological examinations obtained by two different laboratories. One laboratory used endometrial swabs and the other endometrial biopsies for the examinations. A higher proportion of sterile, cytology positive cases were found in the laboratory using swabs (148/401 [37%] vs 12/237 [5%], P < .0001). In both laboratories it was found that positive cytology was less likely to occur when Escherichia coli was isolated than if other species were isolated. This tendency was significant in both laboratories (P < .05 vs P < .0001). 相似文献
119.
Bjørn Florø‐Larsen Anders G. Finstad Ole K. Berg Per H. Olsen 《Ecology of Freshwater Fish》2016,25(2):203-210
In Arctic and alpine lakes, Arctic char [Salvelinus alpinus (L.)] often form two distinct morphs: invertebrate feeders (‘dwarfs’) and piscivores (‘giant or cannibals’). Here, we test for early life history growth variation in dimorphic Arctic char as a proximate explanation for the observed life history variation between the two forms. Char were sampled in 11 alpine and Arctic Norwegian lakes. Dwarfs (defined as sexually mature char less than 15 cm long; N = 304) had a mean total length of 105 mm, whereas the typical cannibal (body length above 20 cm; N = 153) was 388 mm long. A positive correlation between egg size and otolith hatching ring were ascertained in a separate hatching experiment with brown trout (Salmo trutta) and it is assumed that this relationship also is valid for Arctic char, and otolith size was used as a proxy for length. Otolith hatching ring from Arctic char cannibals was larger (mean ± SD; 187 ± 24 μm) than those from dwarfs (mean ± SD; 164 ± 23 μm). There were only minor size differences between dwarfs and cannibals during the next three years, after which dwarfs usually matured. Two mutually nonexclusive, proximate explanations for the differentiation into separate morphs (dwarfs and cannibals) are therefore maternal effects and/or genetic based differentiation. The high catchability of large piscivorous char and low production in alpine and Arctic lake ecosystems may make these stocks particularly vulnerable to overexploitation. 相似文献
120.