| 1. |
- Berndtson, E., et al.
(författare)
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A 1-year epidemiological study of campylobacters in 18 Swedish chicken farms
- 1996
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Ingår i: Preventive Veterinary Medicine. - : Elsevier. - 0167-5877 .- 1873-1716. ; 26:3-4, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Broiler chickens are often intestinal carriers of Campylobacter. During processing, Campylobacter may be spread over the carcass. Thus, undercooked chicken meat, or other foods contaminated by raw chicken can act as a source of infection to humans. This study was conducted to identify risk factors for chicken flocks being colonized with Campylobacter. Eighteen chicken farms with altogether 62 chicken compartments were studied for 1 year with visits during each growing period and sampling of chicken caecal contents at slaughter. Four to six subsequent flocks were raised in each compartment during the study. A detailed questionnaire was used to record farm parameters such as building materials, feed and water equipment, hygiene and management routines. Campylobacter prevalence varied between farms, between growing periods within the farms and also during the year, with lowest prevalence during the spring. Campylobacters were isolated from 27% out of 287 flocks. Only two farms were negative at all samplings. Often the flock following a positive flock in a compartment was negative, indicating that normal cleaning and disinfecting routines are sufficient for eliminating the bacteria from the house. Usually only one serotype was found in each positive flock. Campylobacter occurrence increased with the age of the chickens at slaughter, and also with flock size.Univariable chi-square tests were done of the association between possible risk factors and Campylobacter prevalence. Factors associated with higher Campylobacter prevalence in flocks were lack of or diffuse hygiene barriers, increasing flock size, increasing age at slaughter, short vs. long empty periods, wet litter beds, other poultry nearby or staff handling other poultry, flocks divided before slaughter, staff loading to slaughter at several farms and occurrence of mice. Under Swedish conditions, water does not seem to be a source of infection for chickens. Origin and handling of day-old chickens, feed additives, houses and litter were not associated with higher Campylobacter prevalence.
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| 2. |
- Alvåsen, Karin, et al.
(författare)
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Risk factors associated with on-farm mortality in Swedish dairy cows
- 2014
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 117, s. 110-120
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Tidskriftsartikel (refereegranskat)abstract
- Dairy cow mortality (unassisted death and euthanasia) has increased, worldwide and in Sweden. On-farm mortality indicates suboptimal herd health or welfare and causes financial loss for the dairy producer. The objective of this study was to identify cow-level risk factors associated with on-farm cow mortality. Cows with at least one calving between 1 July 2008 and 30 June 2009 from herds enrolled in the Swedish official milk recording scheme with >40 cow-years were included. Each cow was followed from the day of calving until she calved again or left the herd (died, slaughtered or sold). The effects of potential risk factors on on-farm cow mortality were analysed using a Weibull proportional hazard model with a gamma distributed frailty effect common to cows within herd. The event of interest (failure) was euthanasia or unassisted death. An observation was right censored if the cow was slaughtered, sold, calved again or had an on-going lactation at 500 days after calving. The lactations were split into seasons (January to April, May to August and September to December) and at 30 and 100 days in milk in order to evaluate seasonal effects and the effect of disease in different lactation stages. Primiparous and multiparous cows were analysed separately. The highest hazards for both primiparous and multiparous cows were found for traumatic events and diseases, both in the lactation stage in which the cow died and in the preceding stage. The hazard was higher in early lactation and lower in 2nd parity compared to higher parities. Increased age at first calving (for primiparous cows), calving between January and April, dystocia and stillbirth also increased the mortality hazard. Differences were also found between breeds, between milk production parameters at first test milking and between management types. The results from this study show the importance of good management and preventive health actions, especially around calving, to avoid mortality in dairy cows. (C) 2014 Elsevier B.V. All rights reserved.
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| 3. |
- Andrée O´ Hara, Elisabeth, et al.
(författare)
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An observational study of the dry period length and its relation to milk yield, health, and fertility in two dairy cow breeds
- 2020
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 175
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Tidskriftsartikel (refereegranskat)abstract
- This study evaluated associations between dry period length (DPL) in dairy cows and energy-corrected milk (ECM) production, health, and fertility, using a dataset involving 78 577 lactations in cows of two breeds, Swedish Red (SR) and Swedish Holstein (SH). Herds with at least 20 cows and at least 20 % purebred SR and at least 20 % SH during the year 2015/2016 were included in the dataset. Cows were divided into parity groups 2 and 3 or older and DPL was classified into six 10-day groups (30-39 to 80-89 d). Associations between DPL and the outcome variables were assessed with linear and generalized linear mixed models. Production of ECM at the first three test milkings and the 305-d lactation was highest in the 50-59 d and 60-69 d DPL groups, and lowest in the 30-39 d and 80-89 d groups (p<0.001). Mastitis and somatic cell count (SCC) did not differ between DPL groups, except at the third test milking, where cows in the 40-49, 50-59, and 60-69 DPL groups had lower SCC (p<0.001) than cows in the 70-79 and 80-89 d groups. The odds ratio (OR) for retained placenta was 1.9 for cows with 30-39 d DPL relative to cows with 60-69 d DPL. Cows in DPL groups 40-49 d and 50-59 ha d the lowest odds of culling (OR=0.89 and 0.92). The OR for culling in cows with DPL 70-79 d and 80-89 was 1.2 and 1.4, respectively, relative to cows with 60-69 d DPL. The conception rate at first insemination did not among between DPL groups. The SR cows produced less ECM than the SH cows, but had lower SCC and lower OR for mastitis, retained placenta, puerperal paresis, and culling within 90 DIM. Although DPL <40 days or >80 days reduced milk production in early lactation and the 305-d lactation, the estimated additional milk production in the preceding lactation in cows with short DPL compensated for this reduction. A DPL of 40 days did not affect health and fertility in comparison with a conventional 60 d DPL, while a DPL of >70 d was unfavorable due to low milk production, increased risk of culling, and decreased fertility. The response to DPL was not affected by breed or parity.
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| 4. |
- Aspán, Anna, et al.
(författare)
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Longitudinal observational study over 38 months of verotoxigenic Escherichia coli O157: H7 status in 126 cattle herds
- 2015
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 121, s. 343-352
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Tidskriftsartikel (refereegranskat)abstract
- Verotoxigenic Escherichia coli O157:H7 (VTEC O157:H7) is an important zoonotic pathogen capable of causing infections in humans, sometimes with severe symptoms such as hemorrhagic colitis and hemolytic uremic syndrome (HUS). It has been reported that a subgroup of VTEC O157:H7, referred to as clade 8, is overrepresented among HUS cases. Cattle are considered to be the main reservoir of VTEC O157:H7 and infected animals shed the bacteria in feces without showing clinical signs of disease. The aims of the present study were: (1) to better understand how the presence of VTEC O157:H7 in the farm environment changes over an extended period of time, (2) to investigate potential risk factors for the presence of the bacteria, and (3) describe the distribution of MLVA types and specifically the occurrence of the hypervirulent strains (clade 8 strains) of VTEC O157:H7. The farm environment of 126 cattle herds in Sweden were sampled from October 2009 to December 2012 (38 months) using pooled pat and overshoe sampling. Each herd was sampled, on average, on 17 occasions (range = 1-20; median = 19), at intervals of 64 days (range = 7-205; median = 58). Verotoxigenic E. coli O157:H7 were detected on one or more occasions in 53% of the herds (n= 67). In these herds, the percentage of positive sampling occasions ranged from 6% to 72% (mean = 19%; median = 17%). Multi-locus variable number tandem repeat analysis (MLVA) typing was performed on isolates from infected herds to identify hypervirulent strains (clade 8). Clustering of MLVA profiles yielded 35 clusters and hypervirulent strains were found in 18 herds; the same cluster was often identified on consecutive samplings and in nearby farms. Using generalized estimating equations, an association was found between the probability of detecting VTEC O157:H7 and status at the preceding sampling, season, herd size, infected neighboring farms and recent introduction of animals. This study showed that the bacteria VTEC O157:H7 were spontaneously cleared from the farm environment in most infected herds over time, and key factors were identified to prevent the spread of VTEC O157:H7 between cattle herds.
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| 5. |
- Backhans, Annette, et al.
(författare)
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Alternatives to the use of antimicrobial agents in pig production: A multi-country expert-ranking of perceived effectiveness, feasibility and return on investment : A multi-country expert-ranking of perceived effectiveness, feasibility and return on investment
- 2015
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 118, s. 457-466
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Tidskriftsartikel (refereegranskat)abstract
- Nineteen alternatives to antimicrobial agents were ranked on perceived effectiveness, feasibility and return on investment (ROI) from 0 (not effective, not feasible, no ROI) to 10 (fully effective, completely feasible, maximum ROI) by 111 pig health experts from Belgium, Denmark, France, Germany, Sweden and Switzerland.The top 5 measures in terms of perceived effectiveness were (1) improved internal biosecurity, (2) improved external biosecurity, (3) improved climate/environmental conditions, (4) high health/Specific Pathogen Free/disease eradication and (5) increased vaccination. The top 5 measures in terms of perceived feasibility were (1) increased vaccination, (2) increased use of anti-inflammatory products, (3) improved water quality, (4) feed quality/optimization and (5) use of zinc/metals. The top 5 measures in terms of perceived ROI were (1) improved internal biosecurity, (2) zinc/metals, (3) diagnostics/action plan, (4) feed quality/optimization and (5) climate/environmental improvements. Univariate linear regression showed that veterinary practitioners rank internal biosecurity, vaccination, use of zinc/metals, feed quality optimization and climate/environmental on average highest, while researchers and professors focused more on increased use of diagnostics and action plans. Financial incentives/penalties ranked low in all countries. Belgian respondents ranked feed quality significantly lower compared to the German respondents while reduction of stocking density was ranked higher in Belgium compared to Denmark. Categorical Principal Component Analysis applied to the average ranking supported the finding that veterinary practitioners had a preference for more practical, common and already known alternatives.The results showed that improvements in biosecurity, increased use of vaccination, use of zinc/metals, feed quality improvement and regular diagnostic testing combined with a clear action plan were perceived to be the most promising alternatives to antimicrobials in industrial pig production based on combined effectiveness, feasibility and ROI. (C) 2015 Elsevier B.V. All rights reserved.
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| 6. |
- Backhans, Annette, et al.
(författare)
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Herd-specific interventions to reduce antimicrobial usage in pig production without jeopardising technical and economic performance
- 2017
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 144, s. 167-178
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Tidskriftsartikel (refereegranskat)abstract
- Pig farmers are strongly encouraged to reduce their antimicrobial usage in order to reduce the risk of antimicrobial resistance. Herd-level intervention is needed to achieve national and European reduction targets. Alternative, especially preventive measures, have to be implemented to reduce the need for antimicrobial treatments. However, little is known about the feasibility, effectiveness and return on investment of such measures. The objective of this study was to assess, across four countries, the technical and economic impact of herd-specific interventions aiming at reducing antimicrobial usage in pig production while implementing alternative measures.An intervention study was conducted between February 2014 and August 2015 in 70 farrow-to-finish pig farms located in Belgium, France, Germany and Sweden. Herd-specific interventions were defined together with the farmer and the herd veterinarian. Farms were followed over one year and their antimicrobial usage and technical performance were compared with values from the year before intervention. Compliance with the intervention plan was also monitored. Changes in margin over feed cost and net farm profit were estimated in a subset of 33 Belgian and French farms with sufficient data, using deterministic and stochastic modeling.Following interventions, a substantial reduction in antimicrobial use was achieved without negative impact the overall farm technical performance. A median reduction of 47.0% of antimicrobial usage was achieved across four countries when expressed in terms of treatment incidence from birth to slaughter, corresponding to a 30.5% median reduction of antimicrobial expenditures. Farm compliance with intervention plans was high (median: 93%; min-max: 20; 100) and farms with higher compliance tended to achieve bigger reduction (rho = -0.18, p = 0.162). No association was found between achieved reduction and type or number of alternative measures implemented. Mortality in suckling piglets, weaners and fatteners, daily weight gain and feed conversion ratio did not significantly change over the course of the study, while the number of weaned piglets per sow per year slightly increased. The median change in net farm profit among Belgian and French farms was estimated to be (sic)4.46 (Q25-Q75:-32.54; 80.50) and (sic)1.23 (Q25-Q75:-32.55; 74.45) per sow per year using the detererministic and stochastic models, respectively. It was more influenced by a change in feed conversion ratio and daily weight gain than by a change in antimicrobial expenditures or intervention direct net cost. Therefore, costs of alternative measures should not be perceived as a barrier, but rather as an opportunity to optimise production practices for sustained productivity and improved animal health. (C) 2017 Elsevier B.V. All rights reserved.
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| 7. |
- Backhans, Annette, et al.
(författare)
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Perceptions of antimicrobial usage, antimicrobial resistance and policy measures to reduce antimicrobial usage in convenient samples of Belgian, French, German, Swedish and Swiss pig farmers
- 2015
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 119, s. 10-20
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Tidskriftsartikel (refereegranskat)abstract
- We conducted a survey among convenient samples of pig farmers (N=281) in Belgium, France, Germany, Sweden and Switzerland. We identified some significant differences among the five investigated countries (independent variable) regarding farmers' antimicrobial usage compared to their own country and worries related to pig farming (dependent variables), but most of the differences were rather small. In general, farmers perceived their own antimicrobial usage to be lower than that of their peers in the same country and lower than or similar to that of farmers from other countries. This may be a consequence of our convenience sample, resulting in self-selection of highly motivated farmers. Farmers were significantly more worried about financial/legal issues than about antimicrobial resistance. They believed that a reduction in revenues for slaughter pigs treated with a large amount of antimicrobials would have the most impact on reduced antimicrobial usage in their country. Further, farmers who were more worried about antimicrobial resistance and who estimated their own antimicrobial usage as lower than their fellow countrymen, perceived more impact from policy measures on the reduction of antimicrobials. Our results indicated that the same policy measures can be applied to reduce antimicrobial usage in pig farming in all five countries. Moreover, it seems worthwhile to increase pig farmers' awareness of the threat of antimicrobial resistance and its relation to antimicrobial usage; not only because pig farmers appeared little worried about antimicrobial usage but also because it affected farmers' perception of policy measures to reduce antimicrobial usage. Our samples were not representative for the national pig farmer populations. Further research is therefore needed to examine to what extent our findings can be generalised to these populations and to farmers in other countries. (C) 2015 Elsevier B.V. All rights reserved.
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| 8. |
- Bett, B, et al.
(författare)
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Effects of climate change on the occurrence and distribution of livestock diseases.
- 2017
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 137:Pt B, s. 119-129
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Tidskriftsartikel (refereegranskat)abstract
- The planet's mean air and ocean temperatures have been rising over the last century because of increasing greenhouse gas (GHG) emissions. These changes have substantial effects on the epidemiology of infectious diseases. We describe direct and indirect processes linking climate change and infectious diseases in livestock with reference to specific case studies. Some of the studies are used to show a positive association between temperature and expansion of the geographical ranges of arthropod vectors (e.g. Culicoides imicola, which transmits bluetongue virus) while others are used to illustrate an opposite trend (e.g. tsetse flies that transmit a range of trypanosome parasites in sub-Saharan Africa). We further describe a positive association between extreme events: droughts and El Niño/southern oscillation (ENSO) weather patterns and Rift Valley fever outbreaks in East Africa and some adaptation practices used to mitigate the impacts of climate change that may increase risk of exposure to infectious pathogens. We conclude by outlining mitigation and adaptation measures that can be used specifically in the livestock sector to minimize the impacts of climate change-associated livestock diseases.
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| 9. |
- Björkman, Camilla
(författare)
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Seroprevalence and spatial distribution of Neospora caninum in a population of beef cattle
- 2009
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 92, s. 116-122
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Tidskriftsartikel (refereegranskat)abstract
- A cross-sectional serological survey for Neospora caninum was carried out in Swedish beef cattle in order to estimate the seroprevalence and investigate any geographical patterns of the infection. Blood samples were collected from 2754 animals in 2130 herds and analysed for presence of antibodies to N. caninum. The study included 18.5% of all Swedish beef herds. Spatial autocorrelation was assessed by calculating Moran's I and cluster detection was performed using LISA- and spatial scan statistics. The seroprevalence of N. caninum was 2.8% (95% Cl: 2.18-3.44). Positive samples were found only in the southern half of Sweden. Moran's I was positive (I=0.045, p < 0.01) and indicated global spatial autocorrelation. Using the spatial scan test based on a Bernoulli model, a cluster comprising 16 postal code areas and including 19 seropositive animals was identified. The results indicate that there is a cluster of higher risk of N. caninum (relative risk = 3.95) in the southern part of Sweden, in the counties of Kronoberg and Skane. This is the first report on the seroprevalence of N. caninum in beef cattle in Sweden. (C) 2009 Elsevier B.V. All rights reserved.
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| 10. |
- Blanco Penedo, Isabel, et al.
(författare)
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Assessing, and understanding, European organic dairy farmers’ intentions to improve herd health
- 2016
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 133, s. 84-96
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Tidskriftsartikel (refereegranskat)abstract
- Many believe the health status of organic dairy herds in Europe should be improved to meet consumers' and legislators' expectations to improve animal welfare. This paper reports on a study in four countries that examined dairy farmers' intentions towards improving the health status of their organic herds through the use of the Theory of Planned Behaviour. It was found that farmers across the countries were positive about taking additional preventative measures to improve the health status of their herds. They believed this would not only improve herd physical performance, such as milk yield and fertility, but also achieve greater cost effectiveness and improved job satisfaction for them.Most study farmers would implement a tailored package of improvement measures designed by the study team with higher uptake most likely being by younger farmers, those who make greater use of veterinarians and professional advisory services, and those supplying specialist milk-marketing chains. Furthermore, farmers will be most likely to take-up additional health promotion if compatible with their everyday activities and if they have strong business performance goals aimed at maximising the physical performance of the herd.
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