In calf rearing, the first weeks of life are critical and associated with the highest mortality due to enteric and respiratory diseases. A well-implemented hygiene management can help to protect calves’ health preventively by reducing the load of pathogenic bacteria and interrupting infection chains. The aim of this study was to identify deficiencies in hygiene management of individually housed dairy calves by surveying current practice and examining feeding and housing equipment with different hygiene indicators. On 11 farms, different locations in 2 pens or hutches for individual calf rearing prepared for restocking and 2 feeding buckets per farm, including the inner and outer surfaces of artificial teats, were visually scored for cleanliness and sampled with swabs (housing equipment: n = 167; feeding equipment: n = 120). The sanitation of floors was tested with sock samples (n = 41). A total of 328 samples were analyzed for adenosine triphosphate (ATP) and protein residues, aerobic total viable count (TVC), total coliform count (TCC), Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum β-lactamase-producing bacteria (ESBL), and Salmonella spp. After evaluation of these results, the farmers were informed about the findings and trained on improvement in hygiene management personally. The sampling was repeated after 1 year to detect possible changes in hygiene management. The highest bacterial loads (TVC, TCC, and E. coli) were observed in feeding equipment, especially the inner teat of milk feeding buckets. Environmental samples, primarily the sidewalls and back walls of tested pens and hutches, exhibited the lowest bacterial counts and ATP and protein residues. All samples were negative for MRSA and Salmonella spp. In 10.5% of all samples, ESBL was detected, and in 6.8%, ESBL E. coli was detected, predominately in sock samples, followed by feeding equipment samples. Training in hygiene management showed only limited effects. In conclusion, there is still great potential to improve the implementation of hygiene measures in individual calf housing. In particular, more attention should be paid to the cleaning of feeding buckets and artificial teats, as this is a simple means of interrupting the possible spread of pathogens among calves.

To improve the welfare of livestock, it is important to assess management practices on farms and to identify areas where current scientific recommendations are rarely implemented. Differences in the implementation of recommendations might be explained by the individual farm as well as the characteristics of survey respondents and their attitude toward animal welfare. Hence, the aim of this study was to assess dairy calf management practices, compare them with current scientific recommendations, and to explore factors that influence implementation of the recommended management practices. A 1.5-h interview was performed with stockpersons on 42 dairy farms (mean herd size ± SD = 149.9 ± 16.6 cows) distributed across western Germany in 2018 to 2019. We observed that the management of unweaned calves varied greatly from farm to farm in aspects such as milk-feeding protocols; timing of grouping and disbudding; and access to water, roughage, and concentrate. Major deviations from management recommendations were (1) cleaning calving pen only by removal of bedding without a following disinfection before restocking on 23.8% farms, cleaning of teat buckets without detergents and disinfection (23.8 and 11.9% of farms, respectively), and failure to disinfect navels (29.3% of farms); (2) separating calf and dam after only 5 to 8 h postpartum for calving at night in 97.6% farms and unchecked colostrum quality by 23.8% of survey respondents; (3) feeding waste milk by 72.4% of the farms surveyed; and (4) removing supernumerary teats and disbudding without local anesthesia (90 and 80% farms surveyed, respectively). The number of implemented recommendations on the farms surveyed correlated with who was responsible for calf rearing, and whether prioritizing animal welfare was considered important by the respondents. This study indicated that limitations of individual housing systems, time management, the stockperson's knowledge, and the stockperson's ability to relate to animals posed challenges in implementation of the recommendations. Further research on challenges in calf management and how to overcome them would be helpful to improve calves' welfare in current husbandry systems.

Despite the importance of livestock drinking water quality on animal physiology, welfare, and performance, influences such as biofilm formation on trough surfaces on microbial water quality are rarely researched. The study's objective was to assess the microbial quality of water offered to lactating dairy cows and identify risk factors for poor water quality. We further aimed to determine the impact of biofilm formation on water quality and evaluate rapid test systems to score the hygiene status of dairy troughs on the farm. One hundred five troughs located on 24 typical Western German dairy farms were sampled. Samples of livestock drinking water and biofilm were analyzed for aerobic total viable count (TVC), coliform count (CC), Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and other bacteria resistant to 3 ^rd generation cephalosporins (CRB). Surface protein- and adenosine triphosphate (ATP)-rapid tests were evaluated to detect biofilm formation. The influence of 22 selected fixed and variable trough characteristics on impaired livestock drinking water quality were evaluated by calculating odds ratios. The average TVC, CC, and E. coli counts were 4.4 ± 0.06 (mean ± SD), 1.7 ± 0.1, and 0.6 ± 0.1 log₁₀ cfu ∙ mL ^-1, respectively. CC was detectable in 94.3% of all water samples and E. coli in 48.6%. MRSA was found in pooled livestock drinking water samples of a single farm and CRB on three farms, suggesting that troughs might function as a reservoir of antibiotic-resistant bacteria, thereby contributing to an exchange of antibiotic-resistant bacteria between animals. Risk factors for the impairment of at least one microbial quality criteria (TVC, CC, or E. coli) increased significantly (P < 0.05) when using high-volume troughs, other trough materials than stainless steel, a lower distance to the milking parlor, heavy visible soiling, biofilm formation, and high ambient and high water temperatures. CC (r = 0.46; P < 0.001) and E. coli (r = 0.31; P < 0.01) of water samples correlated with their equivalent in biofilm and with the results of rapid tests on trough surfaces (0.31 >r >0.19; P < 0.05). Addressing the identified risk factors could be an approach to ensure sufficient biological quality of livestock drinking water.

Background: Veterinary medicinal products (VMPs) administered to livestock might affect the environment. Therefore, an environmental risk assessment (ERA) is conducted during the approval process of VMPs. In the European Union (EU), the ERA, which was established approximately 10 years ago, consists of two phases. In the present review, we examined the first phase. In this phase, VMPs are subjected to a decision-making process comprising 19 questions and several tables with default values published in the “Guideline on environmental impact assessment for veterinary medicinal products in support of the VICH guidelines GL6 and GL38 (European Medicines Agency 2016).”Since a proportion of livestock husbandry systems is currently shifting toward ecological husbandry and free-range production systems, there is a lower risk of VMP consumption in general, but livestock excretions possibly containing VMPs might be directly released into the environment instead of being stored and applied as manure. In the present study, the first phase of the current ERA of VMPs in the EU was critically discussed with respect to the changes in animal husbandry. The large number of default values used in the ERA were checked for topicality. In a three-step approach, firstly trends and changes in animal husbandry in Europe that might be relevant for the ERA were collected, secondly, the interactions between Phase I and animal husbandry were evaluated and thirdly, the default values used in Phase I were verified in order to identify research gaps.Results: Several default values used in the current ERA were identified as outdated. Together with the lack of valid data (e.g., on animal husbandry systems or VMP treatments), this may have an impact on the predicted environmental concentration (PEC) as the central decision threshold of the ERA.Conclusions: The results of the present study indicate that an update of the ERA of VMPs in the EU is required to consider the changes in animal husbandry. Several aspects related to this issue are critically discussed.

Consumers, industrial stakeholders, and the legislature demand a stronger focus on animal welfare of all livestock at the farm level by using suitable indicators in self-assessments. In order to deduce farms’ animal welfare status reliably, factors that influence indicators’ results need to be identified. Hence, this study aimed to apply possible animal welfare indicators for unweaned dairy calves on conventional dairy farms with early cow–calf separation and evaluate influencing factors such as age and sex of calves or climatic conditions on the applied indicators’ results. An animal welfare assessment using 7 resource-based and 14 animal-based indicators was conducted at 42 typical Western German dairy farms (844 calves) in 2018 and 2019 by two observers. The effect of influencing factors was calculated by binary and ordinal logistic regressions and expressed as odds ratios. Although every unweaned calf was assessed during the farm visits, most farms had relatively few unweaned calves (average number of calves ± standard deviation = 20.1 ± 6.7 calves), with six farms having not more than 10 calves. The small sample sizes question the usage of those indicators to compare between farms and to set thresholds at the farm level. Only one assessed indicator (cleanliness core body) was not statistically affected by the evaluated influencing factors. Calf age was identified as the most decisive factor, as it affected 16 of 21 evaluated indicators, and calf age distribution on-farm varied greatly. Climatic conditions (ambient temperature and rainfall) influenced resource-based indicators such as access to concentrate and water or the cleanliness of feeding implements and bedding as well as animal-based cleanliness indicators and the occurrence of health-related impairments such as coughing and diarrhea. The authors found differences between calves on farms assessed by the different observers not only in resource-based hygiene indicators but also in animal-based indicators such as hyperthermia or hypothermia, highlighting the need for further evaluation of quality criteria in dairy calf welfare assessments. Nevertheless, animal welfare assessments by farmers themselves could be useful tools to sensitize farmers to animal welfare and thereby improve calves’ welfare.

Increasing ambient temperatures lead to higher water intake and higher risks of microbial growth in cattle troughs. This study aims to analyze drinking water quality and dairy cows’ drinking behavior (n = 8081 drinking episodes) on a commercial farm with 135 and 144 lactating cows in two climatic conditions, considering trough type and cleanliness, respectively. Daily video recording was conducted at two trough types (two open troughs, 70 L; two-valve troughs, variable volume of 5–15 L) in the first two hours after feeding (n = 60 days in total) under cold (December 2019–February 2020) and warm ambient temperatures (September 2021). The trough cleaning scheme allowed cows to access either cleaned or uncleaned troughs in each system. Water quality was tested daily and analyzed at the beginning and end of the trials. In warmer ambient temperatures, fewer and—at uncleaned troughs and open troughs—shorter drinking episodes were recorded, with longer but fewer water intake periods, longer drinking breaks, and fewer sips (p < 0.0001). Considering the drinking episodes, respectively, water intake and drinking breaks in number and duration, the number of sips and the number of agonistic behaviors might optimize dairy cow water supply and hygiene management.