| 1. |
- Hultin Jäderlund, Karin, et al.
(författare)
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Cerebrospinal Fluid PCR and Antibody Concentrations against Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato in Dogs with Neurological Signs
- 2009
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Ingår i: Journal of Veterinary Internal Medicine. - : Wiley. - 0891-6640 .- 1939-1676. ; 23, s. 669-672
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Tidskriftsartikel (refereegranskat)abstract
- The tick-borne bacteria Borrelia burgdorferi sensu lato (sl) and Anaplasma phagocytophilum have been suspected to cause neurological signs in dogs. Diagnosis often has been made based on positive antibody titers in serum of dogs with neurological signs, but a high seroprevalence in dogs in at-risk populations makes diagnosis difficult.To determine if the neurological signs in dogs examined were caused by any of these bacteria.Fifty-four dogs presented to a board-certified neurologist.Prospective study. We divided dogs into 2 groups: those with inflammatory diseases of the central nervous system (CNS) and those with neurological signs from other diseases. Blood and cerebrospinal fluid (CSF) from all dogs were analyzed.Dogs with inflammatory CNS diseases showed no serum antibodies against any of the agents. Among dogs with neurological signs from other diseases, 10.3% had serum antibodies for B. burgdorferi sl and 20.5% for A. phagocytophilum. All blood samples analyzed for bacterial deoxyribonucleic acid (DNA) and all CSF analyzed for antibodies and bacterial DNA for the 2 agents were negative.Based on this study, these bacteria are unlikely causes of neurologic disease in dogs and the presence of serum antibodies alone does not document or establish a definitive diagnosis of CNS disease caused by these organisms. Dogs that have neurologic disease and corresponding serum antibodies against these agents should have additional tests performed to assess for other potential etiologies of the signs.
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| 2. |
- Macias Garcia, B., et al.
(författare)
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Single-Layer Centrifugation Through Colloid Positively Modifies the Sperm Subpopulation Structure of Frozen-Thawed Stallion Spermatozoa
- 2009
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Ingår i: Reproduction in domestic animals. - : Wiley-Blackwell. - 0936-6768 .- 1439-0531. ; 44:3, s. 523-526
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Tidskriftsartikel (refereegranskat)abstract
- The present study attempted to select the subpopulation of stallion spermatozoa that best survived a conventional freezing and thawing procedure, using centrifugation of post-thawed semen samples through a single layer of a glycidoxypropyltrimethoxysilane-coated silica colloid with a species-specific formulation (Androcoll-E (TM)). After freezing and thawing, four sperm subpopulations were identified, listed as FT1 to FT4. While subpopulations FT1 and FT2 were characterized by low sperm velocity, high velocities characterized the ones called FT3 and FT4. The single-layer centrifugation (SLC)-handled sperm sample was enriched in subpopulation FT3, reaching a proportion of 82.6% of the present spermatozoa, in contrast with the non-filtered control post-thawed semen, where this sperm subpopulation only accounted for 16.3% of the total. It is concluded that in the equine industry, the SLC is a practical, easy-to-perform approach to improve the quality of equine frozen-thawed semen samples.
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| 3. |
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| 4. |
- Algers, Bo, et al.
(författare)
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Animal health safety of fresh meat derived from pigs vaccinated against classic swine fever
- 2009
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Ingår i: EFSA Journal. - : Wiley. - 1831-4732.
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Tidskriftsartikel (refereegranskat)abstract
- Classical swine fever (CSF) is a disease that has been causing major socio-economic damages in the EU during the last decades. Although considerable progress has been made in the eradication and prevention of the disease, the threat for an epidemic still exists. The measures to control and eradicate CSF are laid down in Community legislation (Council Directive 2001/89/EC and Commission Decision 2002/106/EC) and are based on stamping-out when CSF is confirmed on pig holdings. Emergency vaccination with 'conventional' live attenuated vaccine or marker vaccine can be used as an additional tool to control and eradicate the disease. In order to support and to improve the control and eradication measures as regards CSF in domestic pigs, EFSA was requested by the Commission to provide scientific advice on the safety of fresh meat (freedom from field virus) derived from vaccinated pigs. Specifically, two terms of reference were given: a) what is the risk that wild-type CSF virus is present in fresh meat obtained from pigs vaccinated in an emergency situation during an outbreak?; and b) what are the sampling schemes and testing procedures needed to detect field virus in fresh meat derived from such vaccinated pigs? Two types of vaccines are currently authorised in the EU for CSF: - A modified live vaccine (MLV, C-strain), which is safe and efficacious, inducing early protection; - An E2 subunit vaccine (E2subV, marker), safe, allowing serological DIVA, but with lower efficacy than MLV. The usefulness of emergency vaccination in order to limit disease spread and avoid excessive culling and economic damages remains to be evaluated. Very limited data related to the presence of CSFV in fresh meat have been generated after the implementation of a non-vaccination strategy. Therefore, a simulation modelling approach was developed to assess the risk of emergency vaccination on the safety of meat compared to the current control of CSF in domestic pigs without vaccination. CSFV is relatively stable in fresh meat and resists the maturation process in meat. Depending on the strain virulence, the age and breed, infected pigs die rapidly or may recover or can develop chronic infections. Viraemia is variable in duration and degree but it is always linked to the spread of virus to other body tissues including skeletal muscles (meat). The risk scenario includes two events that must happen before an infected animal is slaughtered and infected meat released: an infected herd has to escape clinical diagnosis before lifting of restrictions and during the final screening such a herd is not detected due to sample selection or false negative laboratory tests. Three scenarios were evaluated through the model: 1. Stamping-out of CSF detected as infected herds, standstill and pre-emptive culling. 2. Stamping-out of CSF detected as infected herds, standstill and emergency vaccination assuming a rapid protection. 3. Same as 2 but assuming a slower protection and DIVA property. It was concluded from the model that none of the strategies could reduce the risk to absolute zero. Lifting of restrictions can only occur after a certain time span (longer than the viraemic period of infected animals) after the last outbreak, thus the number of virus-positive animals in vaccinated infected herds at lifting will be very small. The model indicated that there is a lower risk of virus in fresh meat after emergency vaccination around outbreaks compared to the conventional strategy including pre-emptive culling, provided that control measures are adjusted to the applied vaccine and test systems. Adjustments may for instance include size of vaccination area, sampling schemes and timing of lift-up of restrictions. Any non-compliance of control measures will increase the risk of infectious animals remaining after lift-up. Chronically infected pigs are a potential hazard for fresh meat. However, in the risk assessment it was assumed that chronically infected pigs will be identified either by clinical signs and/or laboratory tests. Clinical diagnosis is unreliable and laboratory confirmation is needed. Highly sensitive and specific diagnostic assays are available to diagnose CSF. Agent detection tests are more suitable during early stages of infection. A positive rRT-PCR diagnosis indicates that an animal has been infected with the wild type or MLV virus but it is not necessarly still infectious. Antibody detection tests are mainly suitable for monitoring and surveillance purposes, but not for early diagnosis of suspect cases. Concerning the efficiency of the monitoring scheme, it is directly related to the diagnostic systems applied (organ sample, sensitivity, specificity) and to the number of samples taken. In case of selecting samples for rRT-PCR based on fever measurement in vaccinated animals, the sample size should be corrected. In terms of overall efficiency, rRT-PCR for virus detection and ELISA-systems for antibody investigation are the tests of choice. Vaccinated animals, that at an appropriate lift-up time are tested rRT-PCR negative for the wild type virus, can be considered as “zero risk” animals. If only a few animals become infected in a herd, which is possible especially when vaccination is applied, sampling and testing only a proportion of the animals may result in not detecting such an outbreak
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| 5. |
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| 6. |
- Appelgren, Lars-Erik
(författare)
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Homeopathic remedies
- 2009
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 7. |
- Arnemo, Jon
(författare)
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Professorale ytringer
- 2009
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Ingår i: Norsk Veterinaertidsskrift. - 0332-5741. ; 121, s. 238-
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 8. |
- Egenvall, Agneta, et al.
(författare)
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Insurance data for research in companion animals: benefits and limitations
- 2009
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 51
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Forskningsöversikt (refereegranskat)abstract
- The primary aim of this article is to review the use of animal health insurance data in the scientific literature, especially in regard to morbidity or mortality in companion animals and horses. Methods and results were compared among studies on similar health conditions from different nations and years. A further objective was to critically evaluate benefits and limitations of such databases, to suggest ways to maximize their utility and to discuss the future use of animal insurance data for research purposes. Examples of studies on morbidity, mortality and survival estimates in dogs and horses, as well as neoplasia in dogs, are discussed.We conclude that insurance data can and should be used for research purposes in companion animals and horses. Insurance data have been successfully used, e. g. to quantify certain features that may have been hitherto assumed, but unmeasured. Validation of insurance databases is necessary if they are to be used in research. This must include the description of the insured population and an evaluation of the extent to which it represents the source population. Data content and accuracy must be determined over time, including the accuracy/consistency of diagnostic information. Readers must be cautioned as to limitations of the databases and, as always, critically appraise findings and synthesize information with other research. Similar findings from different study designs provide stronger evidence than a sole report. Insurance data can highlight common, expensive and severe conditions that may not be evident from teaching hospital case loads but may be significant burdens on the health of a population.
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| 9. |
- Ekwall, Hans
(författare)
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Cryo-scanning Electron Microscopy Discloses Differences in Dehydration of Frozen Boar Semen Stored in Large Containers
- 2009
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Ingår i: Reproduction in Domestic Animals. - : Wiley. - 0936-6768 .- 1439-0531. ; 44, s. 62-68
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Tidskriftsartikel (refereegranskat)abstract
- In general, freezing in flat plastic polyethylene terephthalate (PET) bags (FlatPacks) at 50 degrees C/min gives better post-thaw viability, in terms of sperm motility and membrane integrity, than does freezing in plastic maxi-straws, probably owing to differences in cryobiology. To test the hypothesis that this better survival post-thaw relates to the degree of sperm dehydration during freezing, the present study investigated the structure of boar semen in a frozen state using cryo-scanning electron microscopy (cryo-SEM) to compare two different packages (FlatPacks and maxi-straws) for single artificial insemination (AI) doses, and three different freezing rates. The semen was split-sample frozen in maxi-straws or FlatPacks (both holding 5 ml) using 3% glycerol as cryoprotectant. Three freezing rates were applied from -5 degrees C to -100 degrees C, namely 2 degrees C/min, 50 degrees C/min and 1200 degrees C/min, the lattermost by plunging the samples into liquid nitrogen (LN(2)). The samples were thereafter fractured into LN(2) and larger areas of extra-cellular, unbound frozen water ('ice lakes') were measured to determine the degree of dehydration of the spermatozoa. These areas decreased in size with an increase in cooling rate, the differences in size being more dramatic for maxi-straws than for FlatPacks. Size of ice lakes was also influenced by location within package in relation to cooling rate, the central values being always smaller in maxi-straws than in Flatpacks (p < 0.05 at 2 degrees C/min and 50 degrees C/min) but not at 1200 degrees C/min, which suggested the FlatPack allows for more homogenous freezing of boar semen.
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| 10. |
- Elzinga, Aant, 1937
(författare)
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Drömmar om en elefant. Några ämneshistoriska anteckningar
- 2009
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Ingår i: Vi vet något. Festskrift till Jan Bärmark, Margareta Hallberg (red.). - Göteborg : University of Gothenburg. - 9789197623919 ; , s. 73-93
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Bakgrunden till ämnet vetenskapsteorins införande vid Göteborgs universitet och dess utveckling såsom en del av "forskning om forskning" och senare koppling till vetenskapsstudier (STS) tas upp på basis av en genomgång av skrifter och dokument fram till 1995. Kapitlet innehåller en tabell med 25 nyckelhändelser mellan 1975-1995. Analogin med "drömman om en elefant" anspelar på titeln på en bok red. av J. Bärmark 1984, Forskning om forskning, eller konsten att beskriva en elefant. Framställningen i kapitlet inkluderar ett avsnitt om det antika indiska ämnet "Elefantologi" och antyder att "Forskning om forskning" blev en "vit elefant".
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| 11. |
- Fröberg, Sofie, et al.
(författare)
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Behaviour of dairy calves suckling the dam in a barn with automatic milking or being fed milk substitute from an automatic feeder in a group pen
- 2009
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Ingår i: Applied Animal Behaviour Science. - : Elsevier BV. - 0168-1591 .- 1872-9045. ; 117, s. 150-158
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate the suckling behaviour of dairy calves allowed to suckle freely in a barn with an automatic milking (AM) system and how their behaviour differed from the behaviour of calves given milk substitute from an automatic feeder. For the first 8 weeks of life, calves of the dairy breed Swedish Red were either suckling freely (FS, n = 16) from the dam in an AM barn or kept in groups with automatic feeding (HM, n = 18) with an allowance of 9 kg of milk substitute per day. All treatments had concentrate and hay ad lib. Focal calves in FS and HM treatments were observed one day in weeks 2, 4 and 8, at 08:00-10:00 and the FS calves' suckling behaviour was observed for a 24-h period once weekly. The HM calves moved, ate concentrate and ate hay more than the FS calves, whereas the FS calves lay down and ruminated more than the HM calves. Cross-sucking and tongue-rolling were displayed in HM but not in FS calves. Of the suckling bouts recorded in FS calves 80% was on the dam. Four calves were recorded suckling solely on their dam, but most of the calves were observed attempting to suckle or suckling on other cows in the group once or twice. The total suckling time and number of suckling bouts during week 2-8 on all cows decreased with increasing calf age. In conclusion, the free-suckling calves ate less solid feed, rested more and exhibited fewer non-nutritive oral and abnormal behaviours compared to the calves fed milk substitute from an automatic feeder, and some calves often suckled on other cows. (C) 2009 Elsevier B.V. All rights reserved.
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| 12. |
- Lord, Peter
(författare)
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Radiographic features of cardiogenic pulmonary edema in dogs with mitral regurgitation: 61 cases (1998-2007)
- 2009
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Ingår i: Journal of the American Veterinary Medical Association. - : American Veterinary Medical Association (AVMA). - 0003-1488. ; 235, s. 1058-1063
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Tidskriftsartikel (refereegranskat)abstract
- Conclusions and Clinical Relevance-in dogs with cardiogenic PE, a symmetric radiographic distribution of increased pulmonary opacity was predominantly associated with a central MRJ, whereas an asymmetric radiographic distribution was usually associated with eccentric MRJ, especially in dogs with MVD. (J Am Vet Med Assoc 2009-1235:1058-1063)
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| 13. |
- Marques, Joana M.
(författare)
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The Spatial Learning Phenotype of Heterozygous Leaner Mice is Robust to Systematic Variation of the Housing Environment
- 2009
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Ingår i: Comparative Medicine. - 1532-0820. ; 59, s. 129-138
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Tidskriftsartikel (refereegranskat)abstract
- Providing stimulation and allowing the performance of motivated behaviors through environmental enrichment improves learning and memory in rodents and delays cognitive impairment in neurodegenerative disease models. The leaner mutation affects the Ca(v)2.1 voltage-gated calcium channel alpha(1A)-subunit gene, and homozygous mice show severe phenotypic alterations. Although several authors have described heterozygous mice as normal, recent studies in our laboratory indicate motor and cognitive impairment in tg(ln)/+ mice. In the present study, we evaluated whether this impairment is robust to systematic variation of the housing environment from barren to standard and furnished (enriched) cages. Wildtype (n = 55) and tg(la)/+ (n = 79) C57B1/6J mice were assigned. randomly to 1 of the 3 housing systems and tested on the Morris water maze at 6, 12, and 20 mo of age. The results confirmed impaired performance in tg(la)/+ mice, particularly in older mice. At 12 and 20 mo, only wildtype (and not tg(la)/+) mice showed evidence of learning (spending increased time in the target quadrant) during the probe trial. Housing also affected performance: at 12 mo, only mice from furnished cages showed evidence of learning, and in aged mice (20 mo), only those housed in more complex environments showed long-term memory (8 mo after previous testing) of the platform position. In conclusion, a heterozygous mutation in a Ca(2+) channel gene causes cognitive deficits in leaner mice that are robust to environmental variation but attenuated by physical and behavioral stimulation.
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| 14. |
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| 15. |
- Skoglund, Björn, 1975-
(författare)
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Following the mevalonate pathway to bone heal alley
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The mevalonate pathway is an important biosynthetic pathway, found in all cells of virtually all known pro- as well as eukaryotic organisms. This thesis is an investigation into the use of two drugs, originally developed for different applications, but both affecting the mevalonate pathway, in to models of fracture repair.Using two different rodent models of fracture repair, a commonly used cholesterol lowering drug (statin) and two drugs used to treat osteoporosis (bisphosphonate) were applied both systemically as well as locally in order to enhance fracture repair.Papers I and II investigate the potential of simvastatin to improve the healing of femoral fractures in mice. Papers III and IV explore the use of two bisphosphonates to improve early fixation of stainless steel screws into rat bone.The statin simvastatin lead to an increased strength of the healing cellus. The application of bisphosphonates increased early screw fixation.It seems clear that both drugs have uses in orthopaedic applications. One interesting avenue of further research would be to combine the two classes of drugs and see if we can get the benefits while at the same time diminishing the drawbacks.
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| 16. |
- Spangenberg, Elin, et al.
(författare)
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Effects of physical activity and group size on animal welfare in laboratory rats
- 2009
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Ingår i: Animal Welfare. - 0962-7286 .- 2054-1538. ; 18, s. 159-169
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate whether moderate physical activity and group size influence physical fitness, the level of social interactions in the home cage and rats' performance in the Elevated Plus Maze and a handling test. Forty-eight male Sprague Dawley rats were kept in groups of two, four or eight for seven weeks in cages adjusted to the group size. Home cage social interactions were studied during direct observations. Half of the number of rats from each cage were subjected to moderate exercise on a treadmill for five weeks. An exercise test was performed at the beginning and end of the experimental period, during which time lactate levels were analysed via blood sampling. Rats living in groups of four or eight performed better in the second exercise test; had more social interactions and showed more activity, open-arm entries and risk assessment in the Elevated Plus Maze test compared to rats living in pairs. The trained rats had lower blood lactate levels in the second exercise test lower bodyweight and plasma insulin levels and had a greater relative heart weight at the end of the study compared to control rats. In conclusion, rats kept in larger groups had more social interactions, a lower lactate response during exercise and showed less emotional reactivity. Moderate treadmill exercise resulted in the expected increase in the rats' physical fitness. The results show that both group size and physical activity are important factors for animal welfare,
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| 17. |
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| 18. |
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| 19. |
- Ahlman, Therese, et al.
(författare)
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Fertility, somatic cell count and milk production in Swedish organic and conventional dairy herds
- 2009
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Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 126, s. 176-182
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Tidskriftsartikel (refereegranskat)abstract
- The share of organic dairy production in EU is increasing and this study describes the herd structure and cow performance in organic and conventional dairy production systems in Sweden. The data included records from 2902718 lactations, collected in organic (n=471) and conventional (n = 13976) herds between 1998 and 2005. Compared with conventional herds, the organic herds were larger and increased more rapidly in size. The replacement rate was slightly lower in organic herds and fewer Swedish Holsteins were used. The statistical analysis of cow performance in the first three lactations showed lower milk, fat and protein production in organic herds, but the increase in production from first to second lactation was larger when expressed in kg milk. Fertility was better for organically managed cows compared to conventionally managed cows, but the somatic cell count (SCC) was higher. However. at a given production level the fertility was slightly worse in organic herds while there was no difference in SCC. No interactions of importance were found between production system and breed for any trait.The results showed that organic and conventional dairy production differed regarding herd structure and cow performance. However, the differences in fertility and SCC found were to a high extent explained by the lower milk yield in organic production and no breed was found to perform better in either system. (C) 2009 Elsevier B.V. All rights reserved.
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| 20. |
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| 21. |
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| 22. |
- Algers, Bo
(författare)
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A risk assessment approach to animal welfare
- 2009
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Ingår i: Welfare of production animals: assessment and management of risks. - 9789086861224 ; :5, s. 223-237
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 23. |
- Algers, Bo, et al.
(författare)
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Control and eradication of classic swine fever in wild boar
- 2009
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Ingår i: EFSA Journal. - : Wiley. - 1831-4732.
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Tidskriftsartikel (refereegranskat)abstract
- Classical swine fever (CSF) is a disease that has been causing major socio-economic damages in the EU during the last decades. Although considerable progress has been made in the eradication and prevention of the disease, the threat for an epidemic still exists. The virus is endemic in the wild boar population of several member states (MS). Wild boar cannot be managed as domestic pigs. Hunting and vaccination have been tentatively used in order to stop transmission by reducing the number of susceptibles. Oral vaccination of wild boar with modified live vaccine based on the C-strain (the only suitable) is used; this vaccine does not allow serological differentiation between vaccinated and infected animals. The aim of the control measures for CSF in wild boar is to reduce the risk of transmission to domestic pigs, to prevent an “endemic phase evolution” or to reduce the endemic phase duration. In order to support and to improve the control and eradication measures as regards CSF in wild boar, EFSA was requested by the Commission to provide scientific advice on the efficacy of the available surveillance, hunting and vaccination measures to control and eradicate CSF in feral pig populations (wild boar), considering the possible use of new diagnostic tests and vaccines. In order to reply to the mandate data were collected from MS through two questionnaires (CSF vaccines, hunting practices and CSF vaccination in wild boar). Data were also extracted from the EU CSF wild boar data base, after requesting permission from the participating MS. Considering that the data received were rather limited and not comparable, the WG decided to use a model in order to fill the gaps in the available knowledge. For the evaluation of the efficacy of CSF control in wild boar a continuous metapopulation compartmental model developed in an EU research project (FP6-5015599-CSFVACCINE&WILDBOAR) was applied. Although the disease manifests in the same manner in both domestic pig and wild boar it is more difficult to identify in wild boar because clinical monitoring of these is hardly possible. Wild boar found dead constitutes the main alert sign of CSF. Hunters and gamekeepers should be instructed to report the finding of each dead wild boar to the competent authority at all times. In case of high-risk situations, a passive surveillance should be complemented by an active serological surveillance. The active sampling of wild boar is not as efficient as in domestic pigs considering that hunting is the sole practical system to obtain samples and that the aim of hunting is quite different. Consequently, the sample size is not controlled by authorities and fits rarely the aim of the survey in terms of detecting the presence of disease at a certain level. In addition, the interpretation of serological results is confounded by maternal derived antibodies (until the 6th month of age), vaccination and the sampling quality. There is no definition at EU level of spatial and temporal units for surveillance, neither for criteria defining a disease free wild boar population. The sample size is not the only factor that dictates the overall sensitivity of surveillance systems. Indeed, wild boar habitat, hunting patterns, and disease distribution should be included when assessing surveillance system sensitivity. After a vaccination campaign, PCR positive animals can be due to modified live vaccines (MLV) but these MLV-vaccinated animals can be cross-checked for wild type CSF virus (genetic DIVA – discriminatory PCR). A positive PCR diagnosis should be considered to indicate that an animal is or has been infected with the wild type or MLV virus but it is not necessarly still infectious. According to previous field experience and to model simulations of a CSF epidemic in a wild boar population and the possible outcomes regarding vaccination: the disease will fade out without any additional control measures in small populations (between 1000 and 1500); hunting is not efficient for CSF control and should not exceed the normal 45% per year. Hunting is currently needed for sampling; vaccination: increases population immunity progressively. The maximum population immunity is only reached after three double campaigns; by one isolated campaign cannot increase population immunity adequately to control CSF and might even aggravate the persistence of CSF; mainly prevents the spread of the infection in neighbouring vaccinated patches; promotes long-term eradication through a progressive reduction of virus transmission to neighbouring areas; always reduces the epidemic peak (number of infected animals/time). Endemic evolution of infection may occur when a low rate of vaccination is achieved; in both infected and not yet infected areas, reaching a minimum target of 40 % of susceptible animals is necessary to obtain a positive control effect, below 20% - will increase probability of endemic stability, above 60% - will always eradicate the infection
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| 25. |
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