Severe Udder Cleft Dermatitis Research Articles

An in-depth investigation of the microbiota and its virulence factors associated with severe udder cleft dermatitis lesions

Udder cleft dermatitis (UCD) is a skin condition affecting the anterior parts of the udder in dairy cattle. In the present study, we aimed to shed light on the microbiota in severe UCD lesions versus healthy udder skin by putting forward a taxonomic and functional profile based on a virulence factor analysis. Through shotgun metagenomic sequencing, we found a high proportion of bacteria in addition to a low abundance of archaea. A distinct clustering of healthy udder skin versus UCD lesion samples was shown by applying principal component analysis and (sparse) partial least squares analysis on the metagenomic data. Proteobacteria, Bacillota, and Actinomycetota were among the most abundant phyla in healthy udder skin samples. In UCD samples, Bacteroidota was the most abundant phylum. At genus level, Bifidobacterium spp. had the highest relative abundance in healthy skin samples, whereas Porphyromonas spp. and Corynebacterium spp. had the highest relative abundance in UCD samples. In the differential abundance analysis, Porphyromonas spp. and Bacteroides spp. were significantly differentially abundant in UCD samples, whereas Bifidobacterium spp., Staphylococcus sp. AntiMn-1, and Staphylococcus equorum were more commonly found in healthy samples. Moreover, the abundance of several treponeme phylotypes was significantly higher in lesion samples. The streptococcal cysteine protease speB was among the most abundant virulence factors present in severe UCD lesions, while a plethora of virulence factors such as the antitoxin relB were downregulated, possibly contributing to creating the ideal wound climate for the dysbiotic community. Network analysis showed healthy lesion samples had a large network ofpositive, correlations between the abundances of beneficial species such as Aerococcus urinaeequi and Bifidobacterium angulatum, indicating that the healthy skin microbiome forms an active protective bacterial network, which is disrupted in case of UCD. In UCD samples, a smaller microbial network mainly consisting of positive correlations between the abundances of Bacteroides fragilis and anaerobic Bacteroidota was exposed. Moreover, a high correlation between the taxonomic data and virulence factors was revealed, concurrently with 2 separate networks of microbes and virulence factors. One network, matching with the taxonomic findings in the healthy udder skin samples, showcased a community of harmless or beneficial bacteria, such as Bifidobacterium spp. and Butyrivibrio proteoclasticus, associated with hcnB, hcnC, relB, glyoxalase, and cupin 2. The other network, corresponding to UCD samples, consisted of pathogenic or facultative pathogenic and mainly anaerobic bacteria such as Treponema spp., Mycoplasmopsis spp., and bovine gammaherpesvirus 4, that correlated with virulence factors SpvB, fhaB, and haemagglutination activity domain-associated factor. Our results point toward a dysbiotic community with a notable decrease in diversity and evenness, with a loss of normal skin inhabitants and innocuous or useful species making way for predominantly anaerobic, facultative pathogens. The shift in the abundance of virulence factors such as fhaB and SpvB could play a role in the manifestation of a local micro-environment favorable to the microbiome associated with udder skin lesions. Lastly, the presence of specific networks between microbial species, and between microbes and virulence factors was shown.

Recovery from udder cleft dermatitis in dairy cows

Udder cleft dermatitis (UCD) is a common skin problem in dairy cows, localized at the fore udder attachment or between the udder halves. The main objectives of this study were to investigate spontaneous recovery from UCD in a longitudinal study and to investigate the treatment effect on UCD of a topical spray containing chelated copper and zinc in an additional treatment trial. Spontaneous recovery was investigated during a 1-yr longitudinal study in which 7 Swedish dairy herds were visited 9 times each, at 6-wk intervals. During the visits, all cows milked in the milking parlor were examined for mild and severe UCD, udder conformation traits, hygiene, and hock lesions. Additional cow and herd data were obtained from the Swedish official milk recording scheme. Recovery was defined as 2 consecutive observations of no UCD after a UCD case (1 or more consecutive observations of UCD). The recovery rate was calculated and factors associated with recovery were analyzed using discrete-time survival analysis. A treatment study was conducted in 4 of the herds after completion of the longitudinal study. Cows with UCD were allocated to treatment or a control group, and cows in the treatment group were treated once every day for 14 to 28 d. At follow-up visits on d 14, 28, and 56, all cows were scored for UCD. To investigate the effect of treatment, an ordered logistic regression model was used, with UCD score on d 56 (no, mild, or severe) as the outcome. Other potential explanatory variables were also included in the model. A total of 38% (126 of 329) of the cows in the longitudinal study made a spontaneous recovery from UCD. A long duration of UCD, severe lesions and higher parity reduced the chance of recovery. Among the recovered cows, 47% (59 of 126 cows) had a recurrent case of UCD after the recovery. In the treatment study, there was no difference in UCD score on d 56 between the treatment and control groups. Factors that affected the UCD score on d 56 were the duration of UCD before the treatment study started, UCD score on d 1 and udder conformation. Our findings emphasize the importance of further studies to identify effective treatment regimens as well as further studies to unravel the pathophysiology of UCD to improve the recommendations on how to prevent these lesions.

A shotgun metagenomic investigation of the microbiota of udder cleft dermatitis in comparison to healthy skin in dairy cows.

Udder cleft dermatitis (UCD) is a skin condition affecting the fore udder attachment of dairy cows. UCD may be defined as mild (eczematous skin changes) or severe (open wounds, large skin changes). Our aims were to compare the microbiota of mild and severe UCD lesions with the microbiota of healthy skin from the fore udder attachment of control cows, and to investigate whether mastitis-causing pathogens are present in UCD lesions. Samples were obtained from cows in six dairy herds. In total, 36 UCD samples categorized as mild (n = 17) or severe (n = 19) and 13 control samples were sequenced using a shotgun metagenomic approach and the reads were taxonomically classified based on their k-mer content. The Wilcoxon rank sum test was used to compare the abundance of different taxa between different sample types, as well as to compare the bacterial diversity between samples. A high proportion of bacteria was seen in all samples. Control samples had a higher proportion of archaeal reads, whereas most samples had low proportions of fungi, protozoa and viruses. The bacterial microbiota differed between controls and mild and severe UCD samples in both composition and diversity. Subgroups of UCD samples were visible, characterized by increased proportion of one or a few bacterial genera or species, e.g. Corynebacterium, Staphylococcus, Brevibacterium luteolum, Trueperella pyogenes and Fusobacterium necrophorum. Bifidobacterium spp. were more common in controls compared to UCD samples. The bacterial diversity was higher in controls compared to UCD samples. Bacteria commonly associated with mastitis were uncommon. In conclusion, a dysbiosis of the microbiota of mild and severe UCD samples was seen, characterized by decreased diversity and an increased proportion of certain bacteria. There was no evidence of a specific pathogen causing UCD or that UCD lesions are important reservoirs for mastitis-causing bacteria.

Bacterial flora associated with udder cleft dermatitis in Dutch dairy cows

Udder cleft dermatitis (UCD) or udder sores is a skin lesion, characteristically located around the anterior junction between the udder and abdomen of dairy cows. It is a worldwide problem in dairy herds with a large effect on animal welfare. The etiology and possible infectious origins of UCD are largely unknown; however, specific bacterial or parasitic causes are suggested in the literature. Therefore the aim of this study was to investigate the possible bacteriological, mycological, or parasitic involvement in clinically scored UCD lesions. Bacteriological culture was performed on subcutaneous tissue samples taken postmortem at a depth of 5 to 10 mm of 87 mild or severe UCD lesions or from the same place in healthy cows. Fungal culture was performed on a subset of 22 subcutaneous tissue samples of severe UCD postmortem. To investigate the superficial flora, swabs were taken from normal skin or skin lesions of 15 live animals equally divided over 3 groups: healthy skin or mild and severe UCD lesions. Histopathology, to describe and classify the lesions and to assess the presence of mites, fungi, or bacteria, was performed on 128 tissue samples, taken separately. In severe UCD lesions, Trueperella pyogenes and Bacteroides pyogenes were more frequently present in deep tissue layers and in superficial layers, compared with the same layers in mild UCD lesions or healthy skin. Culturing and histopathology indicated no sign of involvement of treponemes, Staphylococcus aureus, Escherichia coli, fungi, or mites in the UCD lesions. Histopathological examination showed that the majority of the lesions were characterized by chronic aspecific inflammation. Severe UCD lesions more frequently showed chronic active inflammation on histopathology, compared with mild UCD lesions. Due to the cross-sectional character of this study, it is difficult to differentiate cause and effect; however, future preventive and curative measures against UCD should take into account the chronic and anaerobic nature of this illness.

Incidence of udder cleft dermatitis (UCD) in dairy cows and risk factors for transitions to UCD

Udder cleft dermatitis (UCD) is a common skin condition in Swedish dairy cows, affecting the anterior parts of the udder. The main objective of this study was to investigate incidence rate and duration of UCD in a 1-yr longitudinal study. Other objectives were to investigate risk factors for transitions from being healthy to having mild or severe UCD, and from having mild UCD to having severe UCD, and associations between UCD and clinical mastitis, somatic cell count (SCC) and hock lesions. Seven herds were included in the study and visited 9 times each at 6-wk intervals. At the visits, mild and severe UCD lesions, hock lesions, udder conformation traits, and hygiene scores were registered for each cow milked in the milking parlor. Information on breed, parity, days in milk (DIM), results from test milkings (milk production, SCC, and urea level), and veterinary treatments was also obtained. A UCD case was defined as one or several consecutive observations of UCD. The incidence and duration of UCD were described. Mixed-effect logistic regression models were used to analyze associations between potential risk factors and transitions to any type of UCD. Separate risk factor analyses were performed for transitions to mild and severe UCD. Associations with SCC, mastitis, and hock lesions were also analyzed with mixed-effect logistic regression models. The mean overall incidence of new UCD cases for all visits and herds was 0.5 cases per cow-year at risk. Risk factors associated with a higher risk of a transition to any type of UCD and mild UCD were breed (Swedish Red vs. Swedish Holstein), an indentation or fold at the fore udder attachment, and increasing DIM. In addition, a low milk urea level was associated with a lower risk of transition to any type of and mild UCD. Cows with previous mild UCD and high-yielding cows had increased risk for a transition to severe UCD. Cows that had an observed transition to severe UCD had an increased risk of veterinary-treated clinical mastitis within 6 wk after the UCD observation. No associations were found between UCD and SCC or hock lesions. The median observed duration of a UCD case was 12 wk, but most cases did not have an observed start or end during the study period. The observed duration of cases including severe UCD was longer than for cases involving only mild UCD. The high incidence and often long duration of UCD emphasize the need for preventive measures and treatment strategies.

A randomized clinical trial of topical treatments for mild and severe udder cleft dermatitis in Dutch dairy cows

Udder cleft dermatitis (UCD) is a skin lesion in dairy cows affecting the anterior parts of the udder, with the lesions often needing a long time to heal. The lesions can be characterized as mild or severe. The etiology of UCD is not fully understood and studies on the effectiveness of topical treatments have not been published. The objective of this study, therefore, was to conduct a randomized clinical trial to investigate the effectiveness of 2 different topical treatments, one for mild and one for severe UCD lesions, compared with untreated control groups. The treatment and control groups were randomized within herd for mild and severe UCD. The treatments were applied for a maximum period of 12 wk on 8 Dutch dairy farms. Mild UCD lesions were treated once a d 3 times a week on fixed days with a non-sting barrier film. Severe UCD lesions were first stratified into class A (lesion length <5 cm) or class B (lesion length ≥5 cm) and then randomly allocated to treatment or control groups within herd. Both severe lesion classes were treated once per day every day with an enzyme alginogel. Every week, the lesions of affected animals were inspected and photographed by the investigator. These photographs were reviewed weekly by an external wound expert who classified the lesions as mild, severe class A, severe class B, or healed. Based on this classification, the investigator judged weekly whether the lesions had improved compared with their classification of the previous week. For mild UCD lesions, improvement was defined as occurring when lesions were healed. For severe UCD lesions, improvement was defined as a transition from class B to class A, transition from any severe UCD lesion (class A or B) to a mild UCD lesion, or when the lesion was defined as healed. Data were analyzed using a discrete time survival analysis with time to first improvement as dependent variable. In total, data from 214 animals were analyzed to estimate the effectiveness of treatment. Results showed that treatment of mild UCD lesions had no influence on improvement compared with untreated lesions. Treated severe lesions, however, showed 3.4 times more improvement compared with the untreated controls. Improvement varied between herds, and cows with a parity of 5 or higher showed significantly less improvement than first parity animals. Early identification of severe UCD lesions followed by prompt treatment with an enzyme alginogel supports the healing process.

Mild and severe udder cleft dermatitis—Prevalence and risk factors in Swedish dairy herds

Udder cleft dermatitis (UCD) is an inflammatory skin condition affecting the anterior parts of the udder of dairy cows. The lesions may present as mild or severe skin lesions and have been associated with mastitis and digital dermatitis. The full etiology and pathogenesis are not understood and no large-scale studies have investigated prevalence and risk factors. Therefore, the main objectives of the study were to investigate the prevalence of mild and severe UCD in Swedish dairy herds and to identify risk factors associated with such lesions. We also wanted to investigate risk factors for all cases of UCD and to determine whether UCD increases the risk for mastitis and culling. A random sample of 100 freestall dairy herds were included in the study, and each herd was visited once. Cows were registered as having no, mild, or severe UCD. Additional cow and herd data were obtained via observations, interviews, and the Swedish Official Milk Recording Scheme. The data were analyzed using logistic regression models to identify risk factors for mild and severe UCD. In total, data from 3,479 cows in 99 herds were analyzed. The prevalence of mild and severe UCD was 19 and 9%, respectively. Lesions were found in 98 of 99 herds but the within-herd prevalence of mild (0-43%) and severe (0-33%) UCD varied notably between herds. Breed (Swedish Red compared with Swedish Holstein), certain udder conformation traits, and higher parity were risk factors associated with increased risk of UCD. In addition, cows with hock lesions and cows in herds with high incidence of culling due to hoof and leg diseases had a higher risk for mild UCD. More days in milk and high milk yield were cow-related risk factors associated with severe UCD. Three housing-related factors (shorter cubicles, mattress as cubicle base, and cubicles installed before 2001 compared with 2001-2005), a high incidence of veterinary-treated clinical mastitis and culling due to udder diseases, and a low incidence of culling of first-parity cows in early lactation were herd-related risk factors associated with increased risk for severe UCD. In addition, cows in herds with a high proportion of heifers older than 17 mo that were not inseminated were associated with lower risk of all UCD. Finally, UCD was not associated with the outcomes milk somatic cell count, veterinary-treated clinical mastitis, or culling in the multivariable analyses. The etiology of UCD is most likely multifactorial, involving udder conformation traits and other cow-related risk factors as well as herd-related risk factors. The high prevalence of severe UCD lesions in Swedish dairy cows emphasizes the need for preventive measures and efficient treatments.