A study of duration of digital dermatitis lesions after treatment in a Danish dairy herd

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.     

Efficacy of the non-antibiotic paste Protexin Hoof-Care for topical treatment of digital dermatitis in dairy cows

In this study, the efficacy of the non-antibiotic paste Protexin Hoof-Care containing metallic salts and organic acids, was tested for local treatment of 26 acute digital dermatitis lesions. The control group (26 cases) was treated with local application of oxytetracycline spray. These 52 affected limbs with digital dermatitis were diagnosed in 47 dairy cows from eight different farms with slatted floors. The therapeutic effect was evaluated using a scoring system for weightbearing at stance, lameness at walk and pain of the digital dermatitis lesions. The pre-treatment and control examination scores were documented on days 0, 4, 10 and 28. Both treatment regimens were effective, no statistical differences regarding the examined parameters was found between the group treated with the non-antibiotic Protexin Hoof-Care paste and the group treated with oxytetracycline spray. Twenty-seven digital dermatitis lesions required only one treatment with one of these products. A second topical treatment was carried out on day 4 in 13 lesions of the study group and in 12 lesions of the control group. The data of this pilot study indicate that the non-antibiotic paste Protexin Hoof-Care could be a valuable alternative to topical antibiotic treatment for digital dermatitis in dairy cattle.     

Involvement of Guggenheimella bovis in digital dermatitis lesions of dairy cows

Digital dermatitis (DD) of cattle leads to lameness and a decrease of milk production and is responsible for major economic losses worldwide. Although a bacterial aetiology is generally accepted, it still is unclear which microorganisms cause and/or maintain the disease. Recently, a previously undiscovered bacterial species, Guggenheimella bovis, has been isolated from the front of two DD lesions in Swiss cattle and suggested as a potential pathogen. The aims of the present study were to determine the prevalence of G. bovis in 58 German cows suffering from DD via dot blot hybridization, and to analyse the spatial distribution of G. bovis within the affected tissue by fluorescence in situ hybridization (FISH). A species-specific probe, GUBO1, was designed and evaluated. In none of the 58 samples Guggenheimella could be detected, while cultured G. bovis was reliably identified by GUBO1. Further FISH experiments were carried out on two additional biopsies of Swiss cattle tested positive for G. bovis by quantitative PCR and permitted visualization of the newly discovered bacteria in situ. In these biopsies G. bovis proved to be tissue invasive forming characteristic spherical microcolonies not only within the bacterial biofilm but also in seemingly unaffected parts of the tissue not yet reached by the advancing bacterial front. Although the presence of G. bovis does not constitute an essential premise for DD, it seems likely that the bacterial species involved in DD vary, and that in some cases G. bovis is crucial for the development of DD lesions.     

Efficacy of oxytetracycline for treatment of papillomatous digital dermatitis lesions on various anatomic locations in dairy cows

OBJECTIVE: To evaluate efficacy of topical treatment with oxytetracycline solution among dairy cows with papillomatous digital dermatitis (PDD) lesions on the interdigital cleft, heels, or dewclaw. DESIGN: Clinical trial. ANIMALS: 70 dairy cows from a single herd. PROCEDURE: On the basis of anatomic location of PDD lesions, cows were allocated into 1 of 3 groups (interdigital cleft [n = 14], heels [30], or dewclaw [26]) and treated topically with oxytetracycline solution. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion size scores were recorded. RESULTS: On the basis of pain and lesion size scores, oxytetracycline appeared significantly less effective among cows with lesions on the interdigital cleft than for cows with lesions on the heels or the dewclaw. Number of cows with signs of pain or visible lesions after treatment was significantly higher for cows with lesions on the interdigital cleft than for cows with lesions on heels or the dewclaw. CONCLUSIONS AND CLINICAL RELEVANCE: Anatomic location of PDD lesions has an effect on the efficacy of topical treatment with oxytetracycline solution in dairy cows affected with PDD. Cows with lesions on the interdigital cleft were less likely to respond to treatment, compared with cows with lesions on the heels or the dewclaw.     

A study of the dynamics of digital dermatitis in 742 lactating dairy cows

Digital dermatitis (DD) is a contagious disease of cattle affecting the skin of the claw. The disease presents with a range of severities and can be associated with lameness. Information about the disease dynamics of DD is scarce. Parity and lactation stage have been identified as risk factors for DD and studies have also indicated that not all cows are equal regarding their risk of recurrent disease and prospects for cure from DD. The aim of this study was to investigate host heterogeneity to DD and to identify disease patterns of DD and factors associated with the development and resolution of lesions. In three commercial dairy herds, 742 lactating cows were observed for DD lesions weekly for 11 or 12 weeks. The effects of parity, lactation stage and duration of preceding episode on the hazard of transitions between healthy and lesion states were analysed using a multilevel multistate discrete-time model. One or more DD lesions were observed in 460 cows and lesions were observed in 2426 out of 10,585 observations. In total, 1755 uncensored episodes with DD lesions were observed. Early lactation was associated with a reduced risk of developing lesions compared with mid and late lactation. Lesions that developed in late lactation had a greater likelihood of resolution compared with lesions that developed during early lactation. There was a reduced risk of lesions developing in parity 3 compared with parity 1 cows, but an increased risk of lesions developing in parity 2 compared with parity 1 cows. In the present study, the mean duration of uncensored DD episodes was 1.7 weeks indicating that the duration of the majority of DD lesions might be shorter than the 42 days reported previously. The transitions between disease states suggest that DD is a dynamic disease, and that the early stage lesions are more transient than expected from previous studies. We conclude that studies with shorter observation intervals than one week are needed to fully understand and describe the individual and group dynamics of DD.     

Comparison of topical application of oxytetracycline and four nonantibiotic solutions for treatment of papillomatous digital dermatitis in dairy cows

OBJECTIVE: To compare efficacy of topical treatment with oxytetracycline solution or 1 of 4 nonantibiotic solutions among dairy cows with papillomatous digital dermatitis (PDD). DESIGN: Randomized field trial. ANIMALS: 66 cows in a single herd. PROCEDURE: Cows were randomly assigned to be treated with oxytetracycline solution; a commercial formulation of soluble copper, peroxide compound, and a cationic agent; 5% copper sulfate solution; acidified ionized copper solution; hydrogen peroxide-peroxyacetic acid solution; or tap water. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion scores were recorded. RESULTS: On the basis of pain and lesion scores, oxytetracycline and the commercial formulation appeared equally effective for treatment of PDD and significantly more effective than 5% copper sulfate solution, acidified ionized copper solution, hydrogen peroxide-peroxyacetic acid solution, and tap water. Proportions of cows with signs of pain or visible lesions after treatment were significantly lower for cows treated with oxytetracycline or the commercial formulation than for cows in the other groups. CLINICAL IMPLICATIONS: Oxytetracycline and a commercial formulation of soluble copper, peroxide compound, and a cationic agent appeared to be effective for treatment of PDD in dairy cows.     

Curative effect of topical treatment of digital dermatitis with a gel containing activated copper and zinc chelate

The efficacy of two topical treatments for painful ulcerative stage (M2) of bovine digital dermatitis (BDD) lesions was compared in a clinical trial conducted on five dairy farms in 2009 to 2010. The first treatment was a water-based gel with active components copper and zinc (Intra Hoof-fit gel [IHF]) and the second treatment was a topical chlortetracycline spray (CTC spray). The experimental unit for this study was the hindleg with the presence of a BDD lesion. Cure was defined as the transition of an M2 lesion into a healed (M0) or a non-painful chronic stage (M4) of BDD at D28. On day 0, cows with M2 BDD lesions were photographed and were treated with either IHF or CTC. Subsequently, feet were photographed and scored on D28. The cure rate of M2 BDD lesions treated with IHF at D28 was 0.92 (CI 0.84 to 0.96) and was significantly better than for M2 BDD lesions treated with CTC, which was 0.58 (CI 0.47 to 0.68).     

Use of an antibiotic footbath in the treatment of bovine digital dermatitis

One hundred and eleven dairy cows with digital dermatitis, on six commercial farms, were used to test the efficacy of a footbath containing erythromycin for treating the condition. Four days after 55 of the cows had walked through the footbath after two successive milkings their lesions were significantly less active and painful than those of the 56 untreated cows. These 56 cows were then treated in the same way and both groups were re-examined seven days later. There were no significant differences between the clinical signs observed in the two groups, and the benefits of the treatment had persisted for the 11 days of the trial.     

Isolation and characterization of Treponema phagedenis-like spirochetes from digital dermatitis lesions in Swedish dairy cattle

Background

Digital dermatitis in cattle is an emerging infectious disease. Ulcerative lesions are typically located on the plantar skin between the heel bulbs and adjacent to the coronet. Spirochetes of the genus Treponema are found in high numbers in the lesions and are likely to be involved in the pathogenesis. The aim of this study was to obtain pure cultures of spirochetes from cattle with digital dermatitis and to describe them further.

Methods

Tissue samples and swabs from active digital dermatitis lesions were used for culturing. Pure isolates were subjected to, molecular typing through 16S rRNA gene sequencing, pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and an intergenic spacer PCR developed for Treponema spp. as well as API-ZYM and antimicrobial susceptibility tests. The antimicrobial agents used were tiamulin, valnemulin, tylosin, aivlosin, lincomycin and doxycycline.

Results

Seven spirochete isolates from five herds were obtained. Both 16S rRNA gene sequences, which were identical except for three polymorphic nucleotide positions, and the intergenic spacer PCR indicated that all isolates were of one yet unnamed species, most closely related to Treponema phagedenis. The enzymatic profile and antimicrobial susceptibility pattern were also similar for all isolates. However it was possible to separate the isolates through their PFGE and RAPD banding pattern.

Conclusion

This is the first report on isolation of a Treponema sp. from cattle with digital dermatitis in Scandinavia. The phylotype isolated has previously been cultured from samples from cattle in the USA and the UK and is closely related to T. phagedenis. While very similar, the isolates in this study were possible to differentiate through PFGE and RAPD indicating that these methods are suitable for subtyping of this phylotype. No antimicrobial resistance could be detected among the tested isolates.     

Comparison of the effects of two walk-through footbaths on the prevalence of digital dermatitis and interdigital dermatitis on a commercial dairy farm

This field trial was designed to evaluate the effect of treatment with copper chelate or formalin walk-through footbaths on the prevalence of digitalis dermatitis and interdigital dermatitis on a dairy farm. Although there was no difference in effect between the two types of footbath, the probability that interdigital dermatitis improved or remained stable was lower with the copper chelate footbath than with the formalin footbath.     

Association between bovine digital dermatitis treponemes and a range of 'non-healing' bovine hoof disorders

This study describes the association between bovine digital dermatitis (BDD) treponemes and three 'non-healing' bovine hoof horn lesions, namely, 'toe necrosis' (TN), 'non-healing white line disease' (nhWLD) and 'non-healing sole ulcer' (nhSU), which are disorders that involve penetration through the horn capsule to involve the corium. In this study, these non-healing disorders (n=44) were identified as foot lesions that exhibited a topical granular appearance, exuded a typical pungent smell, were severely painful to the animal involved, and typically originated from farms where BDD is endemic. Given the similarities between these 'non-healing' lesions and BDD, the authors subjected samples of diseased tissue to PCR assays to detect the presence of DNA of BDD treponemes. All the three characterised BDD treponeme groups were identified as present together in 84.2, 81.3 and 55.6 per cent of samples of TN (n=19), nhWLD (n=16) and nhSU (n=9), respectively. In contrast, healthy control horn samples from similar sites (n=16) were PCR-negative for the BDD treponemes. Hence, these non-healing hoof lesions were strongly associated with BDD treponemes. Samples from typical heel horn erosions (n=9) were also subjected to BDD treponeme PCR assays and no association could be identified between the BDD treponemes and this horn manifestation.     

Effects of different intervention strategies on the incidence of papillomatous digital dermatitis in dairy cows

The effects of four different intervention strategies on the incidence of severe lesions of digital dermatitis in an experimental dairy herd were compared with the effects of a control strategy consisting of walking the cows twice through a footbath containing 4 per cent formaldehyde on one day a week for 24 weeks. The four alternative strategies were the same treatment every other week; standing for 30 minutes in a footbath containing a 2 per cent multicompound solution on days 0, 7, 28 and 90 after having had their hooves cleaned indirectly with a medium pressure spray of water; walking twice through the multicompound solution on one day a week for 24 weeks; and, walking twice through a footbath containing 3 per cent sodium carbonate on one day a week for 24 weeks. The cows' hooves were inspected every three weeks by one trained claw trimmer who graded the lesions of digital dermatitis. None of the alternative strategies significantly reduced either the number or severity of the lesions in comparison with the control strategy. In the groups treated by the third and fourth strategies there were outbreaks of digital dermatitis in which more than 30 per cent of the cows suffered the most severe type of lesion, and there was a continuously high rate of new infections in the group treated by the fourth strategy.     

Protection of colostral antibodies against bovine leukemia virus infection in calves on a California dairy.

A three-year prospective study involving 244 calves was undertaken on a California dairy to evaluate the protective role of colostral antibodies against bovine leukemia virus (BLV) infection in calves. Calves were followed from birth to the time they left their individual hutch (TLIH), at about 90 days of age. The probability of being infected at TLIH and the daily risk of infection between birth and TLIH were modelled using the logistic and the Cox models, respectively. Calves with no detectable antibodies during the first week of life were up to 2.00 and 2.75 times more likely to be infected at TLIH compared to calves with low and high concentrations of antibodies during the first week of life, respectively (p = 0.01). When the daily risk was modelled, calves without antibodies at the estimated day of infection were up to 3.4 and 11.6 times more likely to become infected than calves with low and high concentrations of antibodies on that day, respectively (p less than 0.001). Results indicated that calfhood infection may be reduced by about 45% through the feeding of colostrum with BLV antibodies. Further reduction in infection may be possible by feeding calves milk powder, milk replacer, and/or milk from noninfected cows. Results also indicated that quantification of the effect of a time-dependent risk factor, such as colostral antibody concentration, might be affected if treated as a fixed factor.     

Factors associated with in utero or periparturient transmission of bovine leukemia virus in calves on a California dairy.

A three-year prospective study involving 143 calves born from infected cows was undertaken on a California dairy to evaluate possible factors of the dam associated with bovine leukemia virus infection in utero or during the periparturient period. In utero or periparturient infection occurred at a rate of 4.8% and was more likely in calves born to cows with an average peripheral blood lymphocyte count during pregnancy greater than 12,000 cells/microL (p = 0.043) or in calves born to cows that developed malignant lymphoma (p = 0.00004), but not in calves born to cows with p-24 antibodies (p = 0.675).     

Patterns of bovine dairy submissions to the California Veterinary Diagnostic Laboratory System.

Dairy cattle submissions to the California Veterinary Diagnostic Laboratory System (CVDLS) were analyzed to determine submitter statistics. Eligible submissions were those received July 1, 1987 through December 31, 1989 for reasons other than regulatory brucellosis serology. A comprehensive list frame of California dairies was constructed from Brucella Ring Test information and served as the comparison population for the study. Analyses were performed based on geographic location, herd size, proximity to a CVDLS laboratory, and frequency of submission. Thirty-nine percent of the 2,490 California dairies in the reference population had submitted specimens greater than or equal to 1 time to the CVDLS during the study period. Twenty-three percent of the reference population had submitted greater than or equal to 2 times. Specimens were more likely to be submitted from larger herds than smaller herds. Larger dairies also submitted specimens more frequently. Dairies in the northern part of the state were more likely to submit specimens and submitted more frequently than southern herds when herd size was accounted for in the analysis. Mean submission rate (+/- SD) for the 970 submitting dairies was 1.4 (+/- 1.8) submissions/year. Forty-six percent of the dairies accounted for 80% of submissions, whereas only 14% of dairies accounted for 50% of all diagnostic dairy submissions.