Validation of disease recordings in Swedish dairy cattle

This thesis examines the completeness of the Swedish dairy disease recording system: it attempts to quantify how much disease the system’s database captures relative to what farmers find and veterinarians treat. Two field studies were conducted. In the first, 177 farmers recorded information about disease events, regardless of whether the disease event had resulted in a veterinary visit. In the second, farm copies of veterinary records (851 records from 112 herds) were collected. The proportion of disease events receiving veterinary treatment was estimated, and measures of disease incidence based on the farmers’ data were compared with incidences estimated from the Dairy Disease Database (ddd). Further, the completeness of the ddd was estimated based on agreement between information in the ddd and farmer-reporting and herd-copies, respectively. Differential completeness was also evaluated. Finally, the probability of a successfully registered disease event for the whole disease recording process was estimated for five different disease complexes, based on the results of both field studies. The overall completeness of veterinary treated disease events in the ddd was estimated to be 71% and 75%, based on the farmers’ recordings and on the farm copies, respectively. Differential completeness linked to regions, veterinary employment type and between different groups of animals was found. The probability of a successfully registered disease event (regardless of veterinary treatment) in the ddd varied between 30% for diarrhoea and 72% for puerperal paresis. Whether or not the farmer contacted a veterinarian was found to be the most influential step in the recording process, followed by whether or not the disease record was registered in the raw data file at the Swedish Dairy Association. Lack of completeness in the ddd will result in conservative disease incidence measures. Underreporting of veterinary treated disease events, as well as undercoverage of farmer-observed events, was found to vary depending on several factors which could introduce bias in estimates based on the ddd, which primarily is a problem if the data are used for epidemiologic research and less so for other areas

Herd-level risk factors associated with cow mortality in Swedish dairy herds

An increase in on-farm mortality (euthanasia and death) in dairy herds has been reported in several countries in the last decade. This does not only imply possible problems with animal welfare, but it also causes economic losses to the farmer. The objective of this study was to evaluate time trends in on-farm dairy cow mortality in Sweden and identify potential herd-level risk factors. Data was retrieved on all Swedish dairy herds enrolled in the milk recording scheme between 2002 and 2010. Herds with a herd size of 40 dead or euthanized cows per 100 cow-years were excluded. Two different models were used: 1 multiple year analysis which included 6,898 herds during the period 2002 to 2010 and 1 single year analysis including 4,252 herds for the year 2010, where other variables that were not present during the entire multiple year study were analyzed. The outcome variable was the number of euthanized and dead cows per year and season. A negative binomial regression model, adjusted for clustering within herd, was applied to both models. Fixed effects in the multiple year analysis were breed, calving interval, herd size, milk yield, region, season, pasture period, and year. Fixed effects in the single year analysis were breed, calving interval, conventional vs. organic farming, herd size, housing system, milk yield, region, and season. The multiple year analysis demonstrated that MR gradually increased from 5.1 to 6.6 events per 100 cow-years during the study period. Swedish MR are consequently on par with, or even greater than, MR among dairy herds in other comparable countries. Higher mortality was associated with larger herd size, longer calving intervals, and herds that had Swedish Holstein as the predominant breed. Lower mortality was observed in herds with a higher herd average milk yield, during the fall and winter, and in organically managed herds. There were regional differences in mortality. An interaction between herd size and season was found in both models. Also, an interaction between housing system and milk yield was found in the single year analysis. This first assessment of on-farm mortality in Swedish dairy herds confirmed that the MR has increased over the last few years. The study also identified some herd-level risk factors

Effect of grazing management on on-farm mortality in Swedish dairy herds

On-farm mortality (death and euthanasia) in dairy cows is a welfare concern which also causes economic losses for the farmer. This study investigated the association between grazing management and on-farm mortality. The results show the importance of summer grazing since low on-farm mortality was associated with access to production pasture for most of the day

A Case-Series Report on The Use of a Salicylic Acid Bandage as a Non-Antibiotic Treatment for Early Detected, Non-Complicated Interdigital Phlegmon in Dairy Cows

Interdigital phlegmon (IP) is an important cause of lameness in cattle. The aim of this study was to evaluate the treatment effect of a salicylic acid bandage in the interdigital space in dairy cows with early detected IP. Dairy cows (n = 109) with IP diagnosed and treated by the farmer were included in the study. On day 0, the rectal temperature, general condition, coronary circumference, and lameness score were recorded. The cow was immobilized in a trimming chute and the interdigital space was cleaned and inspected. For treatment, 1–2 tablespoons of 100% salicylic acid powder were applied into the interdigital space followed by bandaging of the hoof. On days 1–2 and days 3–5, the rectal temperature, the general condition, and the lameness score were recorded. On days 3–5, the cow was restrained, the bandage was taken off, and the coronary circumference was recorded again. Treatment of IP with salicylic acid gave a satisfactory treatment result. Within three–five days, treated cows responded with reduced lameness, lower body temperature, decreased coronary swelling, and an improved general condition compared to the day when the treatment started. Salicylic acid therefore proved to be an alternative in the treatment of early-detected non-complicated IP

Hepatitis of unknown aetiology in children - epidemiological overview of cases reported in Europe, 1 January to 16 June 2022.

Following the report of an excess in paediatric cases of severe acute hepatitis of unknown aetiology by the United Kingdom (UK) on 5 April 2022, 427 cases were reported from 20 countries in the World Health Organization European Region to the European Surveillance System TESSy from 1 January 2022 to 16 June 2022. Here, we analysed demographic, epidemiological, clinical and microbiological data available in TESSy. Of the reported cases, 77.3% were 5 years or younger and 53.5% had a positive test for adenovirus, 10.4% had a positive RT-PCR for SARS-CoV-2 and 10.3% were coinfected with both pathogens. Cases with adenovirus infections were significantly more likely to be admitted to intensive care or high-dependency units (OR = 2.11; 95% CI: 1.18-3.74) and transplanted (OR = 3.36; 95% CI: 1.19-9.55) than cases with a negative test result for adenovirus, but this was no longer observed when looking at this association separately between the UK and other countries. Aetiological studies are needed to ascertain if adenovirus plays a role in this possible emergence of hepatitis cases in children and, if confirmed, the mechanisms that could be involved.S