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.

The holistic approach of “One Health” includes the consideration of possible links between animals, humans, and the environment. In this review, an effort was made to highlight knowledge gaps and various factors that contribute to the transmission of antibiotic-resistant bacteria between these three reservoirs. Due to the broad scope of this topic, we focused on pig production and selected “indicator bacteria”. In this context, the role of the bacteria livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) and extended spectrum beta-lactamases carrying Escherichia coli (ESBL-E) along the pig production was particularly addressed. Hotspots of their prevalence and transmission are, for example, pig stable air for MRSA, or wastewater and manure for ESBL-E, or even humans as vectors in close contact to pigs (farmers and veterinarians). Thus, this review focuses on the biotope “stable environment” where humans and animals are both affected, but also where the end of the food chain is not neglected. We provide basic background information about antibiotics in livestock, MRSA, and ESBL-bacteria. We further present studies (predominantly European studies) in tabular form regarding the risk potentials for the transmission of resistant bacteria for humans, animals, and meat differentiated according to biotopes. However, we cannot guarantee completeness as this was only intended to give a broad superficial overview. We point out sustainable biotope approaches to try to contribute to policy management as critical assessment points in pig housing conditions, environmental care, animal health, and food product safety and quality as well as consumer acceptance have already been defined.

A trial with different concentrations of DL-methionine (DLM) and DL-2-hydroxy-4-methylthiobutanoic acid (DL-HMTBA) in broiler feed was performed to investigate their effect on the meat quality parameters and the shelf life of breast fillet. In total, fillets from 210 male broiler chickens (Ross 308) were tested in seven groups with 30 animals each. Three different concentrations (0.04, 0.12, and 0.32%; on an equimolar basis) of either DLM or DL-HMTBA were added to a basal diet, summing up to seven treatment groups. After slaughter, fillets were packed aerobically and stored at 4°C. The investigated parameters comprised measurements of microbial as well as physicochemical parameters, such as pH, drip loss, cooking loss, and color measurements. Additionally, sensory investigations were conducted and shelf life was calculated. Mean pH values were between 6.1 and 6.4. Drip loss values were low, with mean values below 0.4%. The cooking loss ranged between 22% and 28% on average. The fillets showed a normal initial microbial quality (2.5 log₁₀ cfu/g) and spoilage process with microbial counts of 8.5 log₁₀ cfu/g at the end of storage. The study revealed a significant influence of methionine supplementation on the quality of broiler breast meat in comparison with the basal group. Methionine supplementation led to higher pH values and a higher water binding. Higher concentrations of methionine had a positive influence on the water-holding capacity by lowering the cooking loss. The L^∗ value showed a significant negative correlation to the methionine concentration supplemented. No differences in physicochemical as well as sensory parameters could be detected between both methionine sources. The fillets showed a normal sensory spoilage process and a shelf life of 6 d. White striping was positively correlated to fillet weight as well as color values and significantly affected the Purchase Decision, the sensory investigation, and thus the shelf life of the samples.

Optimal hygiene management is an essential part of maintaining a high standard of health in conventional pig production systems and for the successful interruption of infection chains. Currently, efficiency assessments on cleaning and disinfection are only performed by visual inspection or are neglected completely. The aim of this study was to evaluate the available methods for on farm monitoring of hygiene, identify critical points in pig pens and use the data obtained for training purposes. In addition to visual inspection by assessing the cleanliness, microbiological swab samples, i.e., aerobic total viable count (TVC), total coliform count, methicillin-resistant Staphylococcus aureus (MRSA), and extended-spectrum β-lactamases-producing bacteria (ESBL), swab samples for ATP as well as protein residues and agar contact plates combined with 3 different culture media, were applied and ranked according to their suitability for livestock farming. Samples were collected on at least 15 critical points from one representative pen on 6 pig fattening farms with various hygiene management practices after cleaning and disinfection. After the first sampling, farmers were trained with their individual results, and sampling was repeated 6 mo after training. Nipple drinkers, feeding tubes (external and inner surface), and troughs (external and inner surface) showed the greatest bacterial loads (TVC: 4.5–6.7 log₁₀ cfu cm^-2) and values for ATP and protein residues; therefore, these surfaces could be identified as the most important critical points. Spearman rank correlations (P < 0.01) were found between the different assessment methods, especially for the TVC and ATP (r = 0.82, P < 0.001). For rapid assessment on farms, ATP tests represented an accurate and cost-efficient alternative to microbiological techniques. Training improved cleaning performance as indicated by a lower rating for visual inspection, TVC, ATP, MRSA, and ESBL in the second assessment. The monitoring of cleaning efficiency in pig pens followed by training of the staff constitutes a valuable strategy to limit the spread of infectious diseases and antibiotic-resistant bacteria. Special attention should be paid to the sufficient hygiene of drinkers and feeders.

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.