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A dairy farmer's decision to cull or keep dairy cows is likely a complex decision based on animal health and farm management practices. The present paper investigated the relationship between cow longevity and animal health, and between longevity and farm investments, while controlling for farm-sp ecific charac-teristics and animal management practices, by using Swedish dairy farm and production data for the period 2009 to 2018. We used the ordinary least square and unconditional quantile regression model to perform mean-based and heterogeneous-based analysis, re-spectively. Findings from the study indicate that, on average, animal health has a negative but insignificant effect on dairy herd longevity. This implies that cull-ing is predominantly done for other reasons than poor health status. Investment in farm infrastructure has a positive and significant effect on dairy herd longevity. The investment in farm infrastructure creates room for new or superior recruitment heifers without the need to cull existing dairy cows. Production variables that prolong dairy cow longevity include higher milk yield and an extended calving interval. Findings from this study imply that the relatively short longevity of dairy cows in Sweden compared with some dairy producing countries is not a result of problems with health and welfare. Rather, dairy cow longevity in Sweden hinges on the farmers' investment decisions, farm-specific characteristics and animal management practices.

The aim of this cross-sectional study was to evaluate the prevalence of subclinical mastitis (SCM) and associated risk factors in dairy cows in peri-urban areas of Kigali, Rwanda, and identify causative udder pathogens. A sample of 256 cows from 25 herds was screened with the California Mastitis Test (CMT), and udder quarters with CMT score >= 3 (scale 1-5) were milk sampled for culture and final bacteriological identification with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). All resultant staphylococci species were tested for beta-lactamase production with the clover leaf method. In parallel, herd bulk milk somatic cell count (SCC) of each herd was analysed using a portable device, the DeLaval cell counter. The prevalence of SCM was 43.1% at quarter level and 76.2% at cow level based on CMT test. Multiparous, Holstein cows were 2.50 (C.I = 1.32-4.71) and 10.08 (C.I = 1.54-66.13) times more likely to contract SCM infection than primiparous animals or cows of other breeds, respectively. The median and mean SCC of all herds were 1108 x 10(3) cells/mL and 1179 x 10(3) cells/mL, respectively. The most prevalent pathogens were non-aureus staphylococci (NAS; 40.2%) followed by Staphylococcus aureus (22%) and less prevalent pathogens (6%). Samples with no growth or contamination constituted 30.4% and 1.4% of the diagnoses, respectively. The most prevalent species within NAS were S. epidermidis (38.2%) followed by S. sciuri (19.5%), S. chromogenes (9.8%), and nine less prevalent NAS species (32.5%). Out of 209 staphylococci isolates, 77% exhibited beta-lactamase production. The study shows that there is high prevalence of SCM and high herd bulk milk SCC in herds in Kigali, indicating udder health problems in dairy cows. Additionally, beta-lactamase production among staphylococci species was common. Improved milking hygiene and application of biosecurity measures, or a complete mastitis control plan, is required to lower the prevalence of SCM and minimize the spread of pathogens among dairy cows.

The aim of this study was to generate knowledge on the most important milk quality and safety attributes, including somatic cell count (SCC), total bacterial count (TBC), Escherichia coli, Salmonella, and Brucella spp. antibodies and antibiotic residues in milk in the chain from farm to milk collection center (MCC) in Rwanda. In addition, we investigated farm and management factors associated with high TBC, SCC, and Salmonella counts. Raw milk was sampled at the farm and MCC levels. Milk samples were taken from dairy farms linked to 2 selected MCC in each of the 4 provinces in Rwanda. In total, 406 bulk milk samples from 406 farms and 32 bulk milk samples from 8 MCC were collected and analyzed. Farm milk average SCC varied between 180 × 10

Mastitis in sheep is common and is important both from an economic and from a welfare point of view. It can be either clinical or subclinical, bacterial or, more seldom, lentiviral. There are no data on the national prevalence of subclinical mastitis (SCM) or intramammary infection (IMI), and causative pathogens, in ewes in Sweden. Diagnosis of SCM and/or IMI is based on inflammatory indicators, measured in milk and additional bacteriology. Somatic cell count (SCC) is the most widely used indicator of SCM and/or IMI and can be measured either directly or indirectly with e.g. California Mastitis Test (CMT). However, the use of SCC as an indicator for mastitis and/or IMI in ewes is not fully evaluated, especially not in meat- and pelt producing herds. The aim of this study was therefore to investigate the prevalence of IMI and bacterial panorama in ewes with clinically healthy udders, in meat- and pelt producing herds in Sweden. Moreover, we wanted to define a cut-off for SCC and CMT for detecting ewes with IMI that would be suitable for use under field conditions. Udder half milk samples (n = 2134) were collected at weaning and lambing from meat- and pelt producing ewes (n = 773), in 22 farms in Sweden. Only clinically healthy animals were included in the study. Milk samples were analysed for bacteriology and SCC and were given a CMT score. Intramammary infection was found in 30% of the ewes and in 14% of the udder half milk samples. No bacteria were found in 74% of the milk samples, and mixed flora was found in 12% of the samples. Among the 287 milk samples where IMI was identified, coagulase negative staphylococci (CoNS) were most prevalent (58%) followed by Staphylococcus (S.) aureus (9%) and Mannheimia (M.) haemolytica (6%). Among the 165 CoNS findings S. simulans was the most common (26%), followed by S. warneri, S. equorum, S. xylosus, S. haemolyticus and S. chromogenes . A CMT score of ≥3 and a SCC of ≥500,000 cells/ml at weaning or CMT score ≥3 and a SCC of ≥400,000 cells/ml after lambing gave the highest possible Se at the same time as the highest possible Sp for identifying udder halves with IMI and may be used for screening for IMI in Swedish meet and pelt producing herds. To conclude, one third of Swedish meat- and pelt producing ewes without clinical signs in the udder had IMI in one or both udder halves at weaning and or after lambing, and CoNS was the most common bacterial finding. A high SCC (≥400,000–500,000 cells/ml) was associated with IMI and a difference in having a high (CMT 3–5) or low (CMT 1–2) between udder halves can be used as an indicator of IMI under field conditions.

Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.

Real-time PCR analysis of milk samples is a fast method to identify intramammary infections (IMI) in dairy cows, and has the potential to be used for routine analysis of test milking composite milk samples. However, the results of the PCR analysis can be difficult to interpret. The objective of this study was to compare the sensitivity (Se) and specificity (Sp) of PCR analysis of composite milk samples, and conventional bacteriological culturing (BC) of quarter milk samples, when used to identify cows with IMI. The comparisons were performed for IMI with four common udder pathogens; Staphylococcus aureus (S aureus), Streptococcus dysgalactiae (Str dysgalactiae), Str uberis and coagulase negative staphylococci (CoNS). The Se and Sp of real-time PCR (SePCR; SpPCR) and BC (SeBC; SpBC) was simultaneously estimated using latent class analysis (LCA), studying one pathogen at the time. Milk samples from 970 dairy cows from 25 herds were included. Aseptically collected quarter milk samples taken at the day before test milking (TM), at the day of TM, and at the day after TM, were analyzed using BC. Non-aseptically collected composite milk samples taken at the day of TM were analyzed using PCR. Moreover, the composite milk somatic cell count (SCC) was recorded and summarized by diagnostic test and bacterial finding. LCA was first performed using only test results from samples taken at the day of TM, but in a second analysis BC results from the three consecutive samplings, interpreted in parallel, were included. The SePCR was significantly higher than the SeBC for S aureus, Str dysgalactiae and CoNS in the first analysis, but only for CoNS in the second analysis. The SpPCR was significantly lower than the SpBC for Str dysgalactiae and CoNS. In conclusion, using PCR analysis of composite milk samples, as a diagnostic tool for identifying cows with IMI increased the Se for all the pathogens investigated (although not always significantly), while Sp in general remained on a similar level, compared to BC of quarter milk samples. The use of repeated quarter milk sampling improved the SeBC, making the results of PCR analysis and BC more similar. However, the SCC of cows with IMI according to BC was higher than for cows with IMI according to PCR, suggesting that some of the cows with IMI according to PCR did not have an active inflammation. Hence, extra caution is needed when decisions about treatment of IMI are based on PCR.

Staphylococcus ( S .) aureus is an important pathogen in cheese producing dairy goat farms. The aim of this study was to investigate whether somatic cell count (SCC) and PCR analysis of S . aureus in bulk tank milk (BTM), and/or SCC in udder half milk samples could indicate intramammary infection (IMI) with S. aureus . Milk samples ( n = 1042) were collected from lactating udder halves of 521 lactating does from 16 herds in mid to late lactation. From the same herds 29 BTM samples were collected. Udder half samples were cultured on blood agar plates and the SCC was measured by California mastitis test (CMT) and DeLaval cell counter (DCC–SCC). Bulk tank milk samples were analysed by PCR for presence of S . aureus and by DCC–SCC. In 15% of the udder halves bacteria was found and of these 80% had CNS and 8% had S . aureus . Udder halves infected with S . aureus had significantly higher DCC–SCC and CMT than udder halves not infected ( P P P = 0.0004). There was a significantly higher risk for a doe to have S . aureus IMI in at least one udder half if the CMT was high in one udder half and low in one udder half ( P = 0.04) compared to does with low CMT in both udder halves. Significant associations between BTMSCC, S . aureus positive BTM, or IMI with S . aureus could not be found. However, 6 out of 8 herds with S . aureus IMI were PCR positive for S . aureus at least once. A difference in CMT between milk from udder halves within a doe can be used as an indicator for S . aureus IMI at goat level. On udder half level, milk SCC, measured with DCC or CMT, can be used to detect S . aureus IMI.

The objective of this cross-sectional study was to investigate prevalence, causative udder pathogens and their antimicrobial resistance (AMR), as well as cow and herd risk factors associated with subclinical mastitis (SCM = cows with at least one udder quarter with california mastitis test (CMT) score2) and intramammary infections (IMI) caused by Staphylococcus(S.) aureus or Non aureus staphylococci (NAS) in dairy cows linked to Milk Collection Centers (MCCs) in Rwanda. Screening for SCM with the CMT was done on 572 cows from 404 herds linked to two MCCs in each of four provinces. Milk from udder quarters with a CMT score ≥3 (scale 1-5) was sampled for bacteriological analysis. Antimicrobial resistance was evaluated in 60 selected S. aureus isolates. Multivariable mixed effect and ordinary logistic regression analyses were performed to identify cow and herd level risk factors associated with SCM, NAS or S. aureus IMI in cows. The prevalence of SCM was 37.3 % at quarter level and 62.0 % at cow level. Bacteria were isolated 73.7 % of the cultured milk samples, whereas 23.3 % were culture-negative and 3.0 % were contaminated. Staphylococcus aureus and NAS were the most prevalent pathogens, representing more than half of all bacteriological findings. Staphylococcus chromogenes and S. epidermidis were the most prevalent NAS species identified. Of the S. aureus strains 83.3 % were resistant for penicillin, 100 % for clindamycin and 20 % tetracycline. The risk factor analysis showed that an increased stage of lactation, dirty udder and legs in single cow herds and lack of calf suckling the dam, dirty udder and legs and lack of feeding cow after milking in multiple cow herds were significantly (P0.05) associated with an increased odds of SCM. Similarly, increasing stage of lactation in single cow herds, and housing cows in individual cattle kraal or on earthen floor and hand washing between cows during milking in multiple cow herds were associated with increased odds for NAS IMI. Poor hygiene of milking area in single cow herds and absence of foremilk stripping in multiple cow herds were significantly (P0.05) associated with increased odds for S. aureus IMI in cows. In conclusion, SCM prevalence was high across MCCs. The majority of identified pathogens were contagious in nature and they exhibited resistance to penicillin. Control of the identified risks factors and improved biosecurity through adoption of best practices, and farmer training could contribute to lowering SCM prevalence in Rwanda.

Additional file 2. Results of univariable analyses of 3 sub-groups of herd-related risk factors (general herd and housing-related, management-related and health-related factors) analyzed in mixed-effect logistic regression models for their association with mild and severe hock lesions (HL) based on observations of 3479 cows in 99 Swedish dairy herds. The table also contains information on how the information was obtained and the number of cows in each category.

The aim of this study was to determine the proportion of Dichelobacter nodosus, Fusobacterium necrophorum and Treponema spp. in sheep with different clinical manifestations of footrot compared to healthy sheep both at flock and individual level. The second aim was to characterise D. nodosus with respect to virulence, presence of intA gene and the serogroups.Swab samples (n=1000) from footrot-affected (n=10) and healthy flocks (n=10) were analysed for the presence of D. nodosus, F. necrophorum and Treponema spp. by real-time PCR and culturing (D. nodosus only). Dichelobacter nodosus isolates (n=78) and positive swabs (n=474) were analysed by real-time PCR for the aprV2/B2 and the intA genes and by PCR for the fimA gene (isolates only).D. nodosus was more commonly found in flocks affected with footrot than in clinically healthy flocks. A significant association was found between feet with severe footrot lesions and the aprV2 gene and between feet with moderate or no lesions and the aprB2 gene, respectively. F. necrophorum was more commonly found in flocks with footrot lesions than in flocks without lesions. No significant association was found between sheep flocks affected with footrot and findings of Treponema spp. or the intA gene. Benign D. nodosus of six different serogroups was detected in twelve flocks and virulent D. nodosus of serogroup G in one.In conclusion, D. nodosus and F. necrophorum were more commonly found in feet with footrot than in healthy feet. The majority of D. nodosus detected was benign, while virulent D. nodosus was only detected in a single flock.

Aleutian Disease (AD) is an important disease in mink characterized by a persistent chronic infection typically causing a progressive disease with symptoms such as weight loss, polydipsia, polyuria, reduced reproductive performance and increased herd mortality. Due to lack of success in eradicating AD by stamping out, disease control programs based on estimating the disease progression have been implemented and used in the selection of future breeding animals. The aim of this project was to evaluate the association between the reproductive performance of female mink (expressed as being barren or not and litter size of non-barren females) and the individual AD status (defined as diseased or non-diseased based on the OD450 value in a dried blood spot samples (DBS) VP2 ELISA) while controlling for age and color type. The project included a pilot study with data on OD450 values and reproductive performance of 2067 female mink in one herd and a follow-up study with data from 10,368 primiparous female mink in four different herds. To investigate the association between the reproductive performance and the AD status, a multivariable zero-inflated Poisson regression model was used in the pilot study and an univariable mixed-effect logistic and Poisson regression model was used in the follow-up study. In the pilot study, being barren was significantly associated with age in an interaction with the AD status of the female mink with the highest risk among the primiparous diseased mink and lowest risk among older non-diseased mink (OR=5.8; p

An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses in Sweden raised questions concerning the risk posed by horses to their surroundings following MRSA infections. This initiated a longitudinal study to investigate how long MRSA-infected horses remained positive and to test the sensitivity of different anatomical sampling sites for detection of MRSA. Between October 2008 and June 2010, 9 of 15 horses notified as having MRSA-infected wounds fitted the case criteria for the study. The cases were sampled at five anatomical sites (nostrils, corner of mouth, pastern, perineum, and previous infection site) on six to seven occasions or more during approximately 12–18 months. MRSA-specific broth and agar were used for culture. Verified MRSA isolates were spa -typed. The sensitivity of sampling sites was calculated. The most sensitive sampling site was the nostrils, with a sensitivity of 0.91 (95% CI: 0.59–1.00). The other test sites had a sensitivity of 0–0.09. Individual cases tested positive, but with time all tested negative. The observed carriage time ranged from 55 to 711 days (median = 143, IQR: 111–172 days), but these data should be interpreted with caution since only a small number of cases were studied.

The present study was undertaken to investigate the prevalence of ascarid infections in Swedish commercial laying hens in 2004 and 2008 following a recent nationwide change to alternative housing systems but before anthelmintics became available. Also, the influence on prevalence of farm and flock characteristics and management was studied in 2004. The results showed that the overall prevalence was significantly higher in 2008 (38%; n = 64/169) compared with 2004 (24%; n = 44/186) (P = 0.001). Ascarid infections were rare in caged flocks, including furnished (enriched) cages, both years (2.4 to 4.3%), and were significantly more common in non-cage systems in both years (16.7 to 48.6% in 2004, and 28.6 to 77.1% in 2008 depending on the housing system). There was no significant difference in prevalence between hens kept on litter indoors and free-range/organic hens. The absence of a hygiene barrier at the entrance of the house or unit increased the risk of infection (P < 0.001), which suggests that parasite eggs were introduced horizontally to the farms. The risk of infection also increased with the age of equipment used in the barn; for example, the risk increased with an odds ratio of 7.5 (95% confidence interval = 2.3 to 25) when comparing equipment 1 year old with equipment ≥7 years old. The results of this study show that ascarid infections may re-emerge following a change to alternative housing. With the impending ban on conventional battery cages in the member states of the European Union, ascarid infections are likely to increase in importance and efficient control options such as hygiene barriers should be implemented on all farms.

Approximately 40% of Swedish broiler producers deliver Campylobacter-negative broilers in 90–100% of their flocks, showing that it is possible to produce Campylobacter-free broilers in Sweden. This study investigated risk factors associated with the presence of Campylobacter-positive flocks at Swedish broiler producers. A total of 37 producers, with 90 broiler houses including 144 compartments, participated in the study. An on-farm interview was performed to collect information on potential risk factors for Campylobacter infection in broilers, with questions about farmcharacteristics such as the environment around the farm and broiler houses, design of the broiler houses and on-farm management practices. Negative binomial regression models were used to assess the statistical significance of risk factors associated with the within-farm number of Campylobacter-positive flocks (the outcome). Campylobacter is transmitted in broiler flocks due to multiple factors and several potential sources, illustrating the complexity of Campylobacter epidemiology in broilers. Factors significantly associated with increased proportion of Campylobacter-positive flocks were the presence of other livestock on the farm, or the presence of cattle, swine, poultry or fur animals within 1 km of the farm. Poor or average general tidiness were associated with increased proportion of Campylobacter-positive flocks, but decreased if split slaughter was seldom or never applied or if farm workers changed footwear twice or three times instead of once before entering the broiler house.

Infections with Aleutian disease virus (ADV) cause a progressive hypergammaglobulinemia, immune complex formation and plasma cell infiltrations in internal organs which induce a multi-systemic disease with high mortality. Serum ADV antibodies have traditionally been diagnosed with counter immunoelectrophoresis (CIEP) as a gold standard for qualitative assessment separating infected from non-infected animals, but less laborious ELISA methods have been confirmed to be equally sensitive. A way to simplify the diagnostics further could be to demonstrate antibodies in Dried blood spot samples (DBS). However, quantitative analysis of ADV antibodies in DBS and its correlation to the degree of hypergammaglobulinemia have not been scientifically published. The aim of this paper was to describe the adaptation and validation of the VP2 ELISA to ADV antibody detection in DBS and compare the estimated antibody levels in DBS to CIEP results, the estimated antibody levels and albumin: gamma globulin ratio in serum. The VP2 ELISA worked technically well when transferred from serum to DBS with mean intra-assay and mean inter-assay coefficients of variation within ± 20%. The DBS VP2 ELISA had a sensitivity of 97.3% and specificity of 93.2% compared to CIEP. Further, we found a correlation coefficient between the level of antibodies in DBS and the A:γG ratio of -0.81. The correlation between the A:γG ratio and the OD450 value was superior in DBS compared to serum samples from the same mink with the most pronounced difference at low A:γG ratios. Our results confirmed that the VP2 ELISA could detect ADV antibodies in DBS with a high sensitivity and specificity when employing CIEP as gold standard. The antibody titers estimated with DBS VP2 ELISA were well correlated to the antibody titters and A:γG ratios in serum, and the DBS VP2 ELISA could be an applicable and preferable tool for estimating AD progression in mink.

Background Bacterial urinary tract infection (UTI) is a common reason for antimicrobial therapy in dogs. A reported increase in multi-drug resistance in canine bacterial pathogens, including resistance to extended-spectrum cephalosporins (ESC) is of concern as antimicrobial resistance complicates therapy in dogs. In addition, it is a possible public health concern. The objectives of this study were to investigate the relative prevalence of pathogens in urine samples from dogs with urinary tract infection sampled at referral hospitals, clinics and mixed veterinary practices and to investigate if this was influenced by sample material or by contamination of the culture. The second objective was to assess the susceptibility patterns to clinically relevant antimicrobials and to investigate if this was influenced by whether the samples originated from smaller clinics or from referral hospitals and to perform active screening for the presence of Enterobacteriaceae resistant to ESC. Results Escherichia coli was the most frequently isolated pathogen (68%) followed by staphylococci (11%). E. coli isolates were found significantly more often in pure culture than in contaminated samples. Staphylococcus pseudintermedius and Staphylococcus aureus isolates were significantly more prevalent in pre-incubated samples compared to samples submitted as non-incubated media. Susceptibility to the majority of the tested first-line antimicrobials was common. Multiresistance was rare, and these isolates were all susceptible to at least one relevant antimicrobial. Isolates in samples from small animal clinics or mixed veterinary practices were less likely to be susceptible compared to isolates originating from referral animal hospitals. ESC-resistant Enterobacteriacae isolates were found in one per cent of the positive cultures. Bacteria with transferable ESC resistance were confirmed in one dog. The gene demonstrated was blaCMY2. Conclusions Choice of sample material might influence the possibility of detecting Staphylococcus pseudintermedius and Staphylococcus aureus isolates in clinical cases of UTI in dogs. Based on the study results, use of first-line antimicrobials is a rational empirical antimicrobial therapy for the studied dog population. E. coli was the most prevalent pathogen, but prevalence of infection with ESC resistant Enterobacteriaceae including E. coli was low, as such isolates were found in only one per cent of the positive cultures.

A study was performed with the aim to investigate associations between Campylobacter in chicken caecum, carcass skin, underlying breast muscle and packaged breast fillets. Samples were taken from 285 chickens from 57 flocks and analysed according to ISO 10272. Campylobacter spp. were isolated from caecal samples from 41 flocks. From birds of the same 41 flocks Campylobacter could be detected and quantified in 194 (68%) skin samples. Moreover, Campylobacter spp. were enumerated in 13 (5%) underlying muscle samples originating from 9 of the 41 flocks. The mean number of Campylobacter spp. in the 194 skin samples which could be counted was 2.3 log cfu/g and for the 13 underlying muscle samples 1.3 log cfu/g. Campylobacter could only be quantified in those breast muscle samples with a finding in corresponding skin sample. Five packaged chicken fillets were taken from each 25 of the 57 flocks and analysed both quantitatively and qualitatively. In qualitative analysis Campylobacter was detected in 79 (63%) fillets from 16 flocks and quantified in 24 (19%) samples from 11 flocks. The results showed a significant association (P < 0.05) between findings of Campylobacter on carcass skin (log cfu/g) and the proportion of Campylobacter positive breast muscle samples.

Background: Staphylococcus aureus is an important cause of clinical mastitis in dairy cows worldwide. The cure rate after antimicrobial treatment of clinical S. aureus mastitis is very variable due to both cow and bacterial factors. Studies have shown that bacterial genotype might affect short-term bacteriological and clinical cure, but the long-term outcome has been less studied. The objectives of this study were to investigate associations between bacterial genotype and long-term outcome of veterinary-treated clinical mastitis (VTCM) caused by S. aureus during a follow-up period of 120 days and to study genotype variation among Swedish S. aureus isolates. S. aureus isolates from cases of VTCM were genotyped by pulsed-field gel electrophoresis. Long-term outcome measurements used were somatic cell count (SCC), additional diagnoses of VTCM, milk yield and culling. Isolates were classified into clusters (>80% similarity) and pulsotypes (100% similarity). Clusters and pulsotypes were grouped according to occurrence. Multivariable mixed-effect linear regression models including cow and bacterial factors with possible influence on SCC or milk yield were used to calculate differences in SCC or milk yield between groups. Additional outcome measures were calculated using a test of proportions. Results: The isolates (n = 185) were divided into 18 clusters and 29 pulsotypes. Two pulsotypes were classified as common, and were found in 64% of the cases of VTCM. Remaining isolates were classified as less common or rare pulsotypes. The distribution was similar at cluster level. Outcome was calculated from follow-up data on 111 cows. Significantly lower SCC during the follow-up period was found in cows infected with common clusters compared to in cows infected with less common/rare clusters. The proportion of cows with SCC

Mastitis is an important disease in dairy goat production. Subclinical mastitis is common in goats and is mainly caused by contagious bacteria. Several methods to diagnose mastitis in goats are available but have not all been investigated in healthy udders and at different stages of lactation. The purpose of the study was to investigate the variation in some udder health indicators at different stages of lactation in goats without intramammary infection (IMI). The udder health indicators were: somatic cell counts (SCC) measured by DeLaval Cell Counter (DCC) and estimated by California Mastitis Test (CMT), lactate dehydrogenase (LDH) activity, N-acetyl-β-d-glucoseaminidase (NAGase) activity and alkaline phosphatase (AP) activity.Milk samples from twenty-four clinically healthy dairy goats were collected on two consecutive days in early, mid and late lactation. At milking, each goat's udder half was given a CMT score before udder half milk samples were collected. The milk samples were then analyzed for SCC, LDH, NAGase and AP, and investigated for bacterial growth. Variation in udder health indicators between udder half within goat, samples between sampling days and samples between stages of lactation were investigated using multivariable mixed-effect linear regression and multivariable ordinal logistic regression models.Of the 24 goats, 18 were considered IMI negative at all samplings, 3 goats had inconclusive results for one udder half in late lactation and 3 (12.5%) had IMI positive udder halves in one or more lactation periods. Period of lactation was significantly associated with all udder health indicators with an increase in all indicators at late lactation compared to mid and early lactation. For NAGase and AP, period of lactation was significant as an interaction term with sampling day. NAGase was significantly higher on day 2 compared to day 1 in mid lactation and significantly lower on day 2 than day 1 in late lactation. AP was significantly higher on day 2 compared to day 1 in early lactation and significantly lower on day 2 than day 1 in late lactation. Moreover, for CMT there was a significant association with udder half with a higher general (over period and day) probability of higher CMT scores in the right udder half compared to the left.This study shows that SCC, LDH, NAGase and AP were all affected by period of lactation but also to some extent by sampling day and udder half. This must be considered when interpreting udder health indicators sampled at different stages of lactation. Mastitis is an important disease in dairy goat production. Subclinical mastitis is common in goats and is mainly caused by contagious bacteria. Several methods to diagnose mastitis in goats are available but have not all been investigated in healthy udders and at different stages of lactation. The purpose of the study was to investigate the variation in some udder health indicators at different stages of lactation in goats without intramammary infection (IMI). The udder health indicators were: somatic cell counts (SCC) measured by DeLaval Cell Counter (DCC) and estimated by California Mastitis Test (CMT), lactate dehydrogenase (LDH) activity, N-acetyl-β-d-glucoseaminidase (NAGase) activity and alkaline phosphatase (AP) activity.Milk samples from twenty-four clinically healthy dairy goats were collected on two consecutive days in early, mid and late lactation. At milking, each goat's udder half was given a CMT score before udder half milk samples were collected. The milk samples were then analyzed for SCC, LDH, NAGase and AP, and investigated for bacterial growth. Variation in udder health indicators between udder half within goat, samples between sampling days and samples between stages of lactation were investigated using multivariable mixed-effect linear regression and multivariable ordinal logistic regression models.Of the 24 goats, 18 were considered IMI negative at all samplings, 3 goats had inconclusive results for one udder half in late lactation and 3 (12.5%) had IMI positive udder halves in one or more lactation periods. Period of lactation was significantly associated with all udder health indicators with an increase in all indicators at late lactation compared to mid and early lactation. For NAGase and AP, period of lactation was significant as an interaction term with sampling day. NAGase was significantly higher on day 2 compared to day 1 in mid lactation and significantly lower on day 2 than day 1 in late lactation. AP was significantly higher on day 2 compared to day 1 in early lactation and significantly lower on day 2 than day 1 in late lactation. Moreover, for CMT there was a significant association with udder half with a higher general (over period and day) probability of higher CMT scores in the right udder half compared to the left.This study shows that SCC, LDH, NAGase and AP were all affected by period of lactation but also to some extent by sampling day and udder half. This must be considered when interpreting udder health indicators sampled at different stages of lactation.

Background In Sweden, knowledge about the role of enteropathogenic Escherichia coli in neonatal calf diarrhea and the occurrence of antimicrobial resistance in E. coli from young calves is largely unknown. This has therapeutic concern and such knowledge is also required for prudent use of antimicrobials. Methods In a case control study Esherichia coli isolated from faecal samples from dairy calves were phenotyped by biochemical fingerprinting and analyzed for virulence genes by PCR. Antimicrobial susceptibility was tested by determination of minimum inhibitory concentration (MIC). Farm management data were collected and Fisher's exact test and univariable and multivariable logistic regression analysis were performed. Results Of 95 E. coli tested for antimicrobial susceptibility 61% were resistant to one or more substances and 28% were multi-resistant. The virulence gene F5 (K99) was not found in any isolate. In total, 21 out of 40 of the investigated virulence genes were not detected or rarely detected. The virulence genes espP, irp, and fyuA were more common in resistant E. coli than in fully susceptible isolates (P < 0.05). The virulence gene terZ was associated with calf diarrhea (P ≤ 0.01). The participating 85 herds had a median herd size of 80 lactating cows. Herds with calf diarrhea problems were larger (> 55 cows; P < 0.001), had higher calf mortality (P ≤ 0.01) and calf group feeders were more in use (P < 0.05), compared to herds without calf diarrhea problems. There was no association between calf diarrhea and diversity of enteric E. coli. Conclusions Antimicrobial resistance was common in E. coli from pre-weaned dairy calves, occurring particularly in calves from herds experiencing calf diarrhea problems. The results indicate that more factors than use of antimicrobials influence the epidemiology of resistant E. coli. Enteropathogenic E. coli seems to be an uncommon cause of neonatal calf diarrhea in Swedish dairy herds. In practice, calf diarrhea should be regarded holistically in a context of infectious agents, calf immunity, management practices etc. We therefore advice against routine antimicrobial treatment and recommend that bacteriological cultures, followed by testing for antimicrobial susceptibility and for virulence factors, are used to guide decisions on such treatment.

Background Pre-recorded register data from dairy herds are available in almost all Nordic countries. These databases can be used for research purposes, and one of the research areas is animal welfare. The aim of this study was to investigate if pre-recorded register data could be used to identify herds with good welfare, and to investigate if a combination of register data sets could be used to be able to more correctly distinguish between herds with good welfare and herds with welfare deficiencies. Methods As a first step, nine animal-based measurements on calves, young stock and cows in 55 randomly selected herds were performed on-farm as the basis for a classification of welfare at the herd level. The definition for being a case herd with “good welfare” was no score lying among the 10% worst in any of the nine welfare measurements. Twenty-eight of the 55 herds were cases according to this definition. As a second step, 65 potential welfare indicators, based on register data in a national dairy database, were identified by expert opinion. In the final step, the extent to which the suggested welfare indicators predicted farms’ as having good welfare according to the stated definition was assessed. Moreover, the effect of combining in sequence a previously developed model that identified herds with poor welfare with the present model identifying herds with good welfare was investigated. Results The final set of welfare indicators used to identify herds with good animal welfare included two fertility measures, cow mortality, stillbirth rate, mastitis incidence and incidence of feed-related diseases (including gastrointestinal disturbances but excluding paralyses and cramps). This set had a test sensitivity of correctly classifying herds with no score lying among the 10% worst of the nine welfare measurements of 96 %. However, the specificity of the test was only 56% indicating difficulties for the test to correctly classifying herds with one or more scores lying among the 10% worst. Combining the previously developed model with the present model, improved the welfare classification. Conclusions This study shows that pre-collected register data may be used to give approval to dairy farms with “good welfare” and that combining different sets of register data can improve the classification of herd welfare.

Background United Kingdom, Ireland, Malta and Sweden maintain their national provisions for a transitional period regarding rules concerning rabies vaccination and individual serological test for rabies neutralizing antibodies. The purpose of vaccinating dogs against rabies is to establish pre-exposure immunity and protect individual animals from contracting rabies. The aim of the study was to investigate factors associated with reaching the internationally accepted threshold antibody titre of 0.5 IU/mL after rabies vaccination of dogs. Methods The study was a prospective single cohort study including 6,789 samples from Swedish dogs vaccinated with commercially available vaccines in Sweden, and the dog's antibody responses were determined by the OIE approved FAVN test. Information on potential risk factors; breed, age, gender, date of vaccination, vaccine label and the number of vaccinations, was collected for each dog. Associations between the dependent variable, serological response ≥ 0.5 IU/mL or < 0.5 IU/mL and each of the potential risk factors were investigated using logistic regression analysis. Results Of 6,789 vaccinated dogs, 6,241 (91.9%) had an approved test result of ≥ 0.5 IU/mL. The results of the multivariable logistic regression analysis showed that vaccinating with vaccine B reduced the risk of having antibody titres of < 0.5 IU/mL by 0.2 times compared with vaccination using vaccine A. Breed size was found significant as an interaction with number of vaccinations and age at vaccination as an interaction with day of antibody testing after last vaccination. In summary, larger breeds were at higher risk of having antibody titres of < 0.5 IU/mL but if vaccinated twice this risk was reduced. Moreover, there were a increased risk for dogs < 6 months of age and > 5 years of age to have antibody titres of < 0.5 IU/mL, but this was affected by number of days from vaccination till testing. Conclusions The probability of success of rabies vaccinations of dogs depends on type of vaccine used, number of rabies vaccinations, the breed size of the dog, age at vaccination, and number of days after vaccination when the antibody titres are tested. The need for a booster vaccination regimen is recommended for larger breeds of dog.

Background Streptococcus dysgalactiae and Streptococcus uberis are common causes of clinical mastitis (CM) in dairy cows. In the present study genotype variation of S. dysgalactiae and S. uberis was investigated, as well as the influence of bacterial species, or genotype within species, on the outcome of veterinary-treated CM (VTCM). Isolates of S. dysgalactiae (n = 132) and S. uberis (n = 97) were genotyped using pulsed-field gel electrophoresis. Identical banding patterns were called pulsotypes. Outcome measurements used were cow composite SCC, milk yield, additional registered VTCMs and culling rate during a four-month follow-up period. Results In total, 71 S. dysgalactiae pulsotypes were identified. Nineteen of the pulsotypes were isolated from more than one herd; the remaining pulsotypes were only found once each in the material. All S. uberis isolates were of different pulsotypes. During the follow-up period, the SCC of S. dysgalactiae-cows was significantly lower than the SCC of S. uberis-cows (P

Background Studies outside the Nordic countries have indicated that subclinical mastitis (measured by milk somatic cell count or the California Mastitis Test), intramammary infections (IMI), or blind quarters in beef cows may have negative effects on beef calf growth. Knowledge on prevalence of such udder health problems in Swedish beef cows is scarce. Therefore, the main aim of this study was to investigate subclinical mastitis, IMI and udder conformation in a number of beef cow herds. Production of β-lactamase in staphylococci was also investigated. Associations between certain cow factors and subclinical mastitis and IMI, and associations between cow and calf factors and 200 day calf weaning weight were also studied. The herds were visited once within a month after calving and once at weaning. Udder examination and quarter milk sampling, for somatic cell count and bacteriology, were performed in 8 to 12 cows per herd and occasion. Results Approximately 50%, 40% and 10% of the cows had subclinical mastitis, IMI, and at least one blind quarter, respectively, but the prevalence varied markedly between herds. Intramammary infections (mainly due to staphylococci) were identified in 13-16% of the milk samples. Less than 5% of the staphylococcal isolates produced β-lactamase. Approximately 11% of the cows sampled twice had the same IMI (mostly Staphylococcus aureus) at both samplings. Cow factors of importance for subclinical mastitis and/or IMI were teat and udder shape, breed, parity, presence of blind quarters, and cow hygiene. No significant associations were found between udder health parameters studied and calf weaning weights. Conclusions Subclinical mastitis and IMI, but not blind quarters, were common in beef cows, but the prevalence varied markedly between herds. Most IMI were caused by staphylococci and more than 95% of those were sensitive to penicillin. Cows with large funnel-shaped teats or pendulous udder after calving, and cows with blind quarters were at risk of having subclinical mastitis and/or IMI. Poor hygiene was also a risk factor for udder health problems. No significant associations were found between udder health and calf weaning weight. More studies on risk factors are warranted to improve advisory services on awareness and prevention of mastitis in beef cows.

Background Surgical site infection (SSI) is a common nosocomial infection in dogs and a growing concern in veterinary hospitals as an increase in multidrug-resistant pathogens is reported. Despite the need for rational and prudent antimicrobial use, few peer-reviewed and published veterinary studies have investigated the pathogenic growth including susceptibility patterns of the isolated pathogens in canine SSIs. The first objective of the present study was to estimate the distribution of bacterial pathogens in dogs with SSI and to investigate whether this was influenced by type of surgical procedure (clean, clean-contaminated, contaminated or dirty), duration of hospitalization, wound classification and depth of the infection, or antimicrobial treatment. The second objective was to assess susceptibility patterns to clinically relevant antimicrobials. During three years, four animal referral hospitals and three small animal clinics submitted bacterial swabs from canine SSIs for culture and susceptibility, together with a questionnaire completed by the attending clinician. Results Approximately two thirds of the in total 194 isolates were staphylococci. Staphylococcus pseudintermedius was the most prevalent finding (46%) followed by beta haemolytic Streptococcus spp. (24%). No associations between distribution of the isolated pathogens and classification of the surgical procedure, duration of hospitalization or depth of the SSI were shown, with the exception of Escherichia coli isolates being significantly more often found in deep wound infections than in superficial skin infections. Overall the possibilities of finding first generations antimicrobials to treat the SSIs included in the study were favorable, as the isolated pathogens were mostly without acquired antimicrobial resistance and multidrug resistance was uncommon. There were only three cases of methicillin-resistant S. pseudintermedius-infections (one percent of all isolates), one case of extended-spectrum beta-lactamase producing E. coli-infection, and no methicillin-resistant Staphylococcus aureus infections. Conclusions None of the investigated factors were shown to influence the distribution of bacterial pathogens. The majority of SSIs were caused by staphylococci, and S. pseudintermedius was the most prevalent pathogen. Based on the study results, use of first-line antimicrobials prior to receiving culture and susceptibility results is a rational empirical antimicrobial therapy for the studied dog population.