Across the international dairy industry, the vast majority of dairy herds have dehorned cows. Farmers choose to dehorn calves for different reasons such as easier handling of non-horned cattle and reduced risk of injuries in animals and staff. This review focuses on disbudding by use of hot-iron cautery as is practiced by dairy farmers in calves <3 months of age. We examine welfare effects of the use of NSAIDs in combination with a local anesthetic including indicators relevant for the three major welfare concerns—affective states, basic health, and functioning as well as the possibility to behave naturally. Across indicators of animal welfare, the majority of available evidence suggest that the use of NSAIDs in combination with a local anesthetic is advantageous in terms of animal welfare, and no studies suggest that NSAIDs are a disadvantage to animal welfare. However, irrespective of the welfare concern, use of NSAIDs combined with a local anesthetic does not fully eliminate the welfare challenges from disbudding. Further research is needed in order to fully understand the effects of this medication protocol on calf welfare, including knowledge about the duration of healing and the presence of long-term pain. At present, this lack of knowledge challenges the precise formulation of adequate pain management—in terms of medication protocol, duration, dosage, and type of administration.

The objective of this study was to identify possible risk factors for poor cow hind limb cleanliness in Danish loose-housed, lactating dairy cows. The study was conducted as a cross-sectional study of 1315 cows in 42 commercial Danish dairy herds with primarily Danish Holstein cows. The effect of four cow-level factors (parity, days in milk, daily lying time and lameness) and eight herd-level factors (herd size, milk production, milking system, floor type, access to pasture grazing, floor scraping frequency, hoof bathing frequency and hoof washing frequency) on the risk of having dirtier hind limbs were analysed using ordinal logistic regression fitting a proportional odds model. Cow hind limb cleanliness was scored using an ordinal score from 1 to 4: 1 being clean and 4 being covered in dirt. The odds ratios (ORs) estimated from the proportional odds model depict the effect of a risk factor on the odds of having a higher rather than a lower cleanliness score. First parity cows had an increased risk of being dirtier compared with third parity or older cows (OR 5 1.70). Compared with late lactation, early and mid lactation were associated with an increased risk of being dirtier (OR 5 2.07 and 1.33, respectively). Decreasing the daily time lying by 30 min was associated with an increased risk of being dirtier (OR 5 1.05). Furthermore, an increased risk of being dirtier was found in herds with no pasture access (OR 5 3.75).

Summary 10Digital dermatitis (DD) is a contagious disease of cattle affecting the skin of the claw. The disease 11 presents with a range of severities and can be associated with lameness. Information about the 12 disease dynamics of DD is scarce. Parity and lactation stage have been identified as risk factors for 13 DD and studies have also indicated that not all cows are equal regarding their risk of recurrent 14 disease and prospects for cure from DD. The aim of this study was to investigate host heterogeneity 15 to DD and to identify disease patterns of DD and factors associated with the development and 16 resolution of lesions. In three commercial dairy herds, 742 lactating cows were observed for DD 17 lesions weekly for 11 or 12 weeks. The effects of parity, lactation stage and duration of preceding 18 episode on the hazard of transitions between healthy and lesion states were analysed using a 19 multilevel multistate discrete-time model. One or more DD lesions were observed in 460 cows and 20 lesions were observed in 2426 out of 10585 observations. In total, 1755 uncensored episodes with 21 DD lesions were observed. Early lactation was associated with a reduced risk of developing lesions 22 compared with mid and late lactation. Lesions that developed in late lactation had a greater 23 likelihood of resolution compared with lesions that developed during early lactation. There was a 24Page 2 of 32 reduced risk of lesions developing in parity 3 compared with parity 1 cows, but an increased risk of 25 lesions developing in parity 2 compared with parity 1 cows. In the present study, the mean duration 26 of uncensored DD episodes was 1.7 weeks indicating that the duration of the majority of DD lesions 27 might be shorter than the 42 days reported previously. The transitions between disease states 28 suggest that DD is a dynamic disease, and that the early stage lesions are more transient than 29expected from previous studies. We conclude that studies with shorter observation intervals than 30 one week are needed to fully understand and describe the individual and group dynamics of DD. 31 32

Bovine respiratory and enteric diseases have a profound negative impact on animal, health, welfare, and productivity. A vast number of viruses and bacteria are associated with the diseases. Pathogen detection using real-time PCR (rtPCR) assays performed on traditional rtPCR platforms are costly and time consuming and by that limit the use of diagnostics in bovine medicine. To diminish these limitations, we have developed a high-throughput rtPCR system (BioMark HD; Fluidigm) for simultaneous detection of the 11 most important respiratory and enteric viral and bacterial pathogens. The sensitivity and specificity of the rtPCR assays on the high-throughput platform was comparable with that of the traditional rtPCR platform. Pools consisting of positive and negative individual field samples were tested in the high-throughput rtPCR system in order to investigate the effect of an individual sample in a pool. The pool tests showed that irrespective of the size of the pool, a high-range positive individual sample had a high influence on the cycle quantification value of the pool compared with the influence of a low-range positive individual sample. To validate the test on field samples, 2,393 nasal swab and 2,379 fecal samples were tested on the high-throughput rtPCR system as pools in order to determine the occurrence of the 11 pathogens in 100 Danish herds (83 dairy and 17 veal herds). In the dairy calves, Pasteurella multocida (38.4%), rotavirus A (27.4%), Mycoplasma spp. (26.2%), and Trueperella pyogenes (25.5%) were the most prevalent pathogens, while P. multocida (71.4%), Mycoplasma spp. (58.9%), Mannheimia haemolytica (53.6%), and Mycoplasma bovis (42.9%) were the most often detected pathogens in the veal calves. The established high-throughput system provides new possibilities for analysis of bovine samples, since the system enables testing of multiple samples for the presence of different pathogens in the same analysis test even with reduced costs and turnover time.

Digital dermatitis (DD) is a contagious disease of cattle affecting the skin adjacent to the claws. Disease dynamics of DD have been described to some extend, but we still need to quantify the duration of lesions and look into non-treatment factors affecting this. The aim of this study was to estimate the duration of lesions due to DD and to evaluate parity and lactation stage as potential risk factors for longer duration of such lesions. An estimate of the duration of lesions will be a valuable parameter in the evaluation of the economic impact of the disease and will additionally allow estimates of incidence based on prevalence figures. From May 2007 until November 2008, lesions associated with DD in the hind legs of 151 Danish Holstein cows at the Danish Cattle Research Centre were clinically scored on fifteen occasions. The mean interval between recordings was 39 days. Onset and end of each new case were estimated as midway between recordings prior to a change in the presence or absence of a lesion. Kaplan-Meier survival functions and Cox proportional hazard regression were performed to estimate the duration and analyse differences in the duration of lesions between primi-and multiparous cows and between different stages in lactation at onset of the lesion. The median duration of lesions were estimated to be 42 days, less than most previous published estimates. The relatively aggressive regime of topical treatment in the study herd might have shortened the duration of the lesions. Furthermore the comparatively long interval between recordings introduced an element of uncertainty in this estimate. No significant effects of parity or days in milk at lesion onset on the duration of DD were found using these data though lesions developed earlier in the lactation may have a longer duration. Further data would be needed to confirm the latter.