A field evaluation of a footbathing solution for the control of digital dermatitis in cattle.

Footbathing is one of the most commonly used methods for controlling digital dermatitis (DD). A farm-based trial was undertaken using six dairy herds involving over 600 cubicle-housed Holstein-Friesian cattle. Split footbaths (length 2.2m) were used to compare the efficacy of two dips, namely, a positive control (5% copper sulphate) and a non-heavy metal-based proprietary dip. The dips were used from early January 2009 for a minimum of 103 days, bathing twice a day for 3 consecutive days every week, using one footbath (three herds) or two in line (three herds). The lesions of DD on the hind feet of cattle were scored by borescope while the animals were being milked, on three occasions (at approximately days 0, 55 and 110) and then compared both directly and by calculating the change in severity from the previous examination (when possible). Data from the 408 cows that had their feet examined for lesions on all three occasions were analysed separately. A reduction in lesion score was seen for both footbath products, but feet bathed in 5% copper sulphate improved more (OR=1.6, CI: 1.14-2.32; P<0.01), and, irrespective of solution, there was a significantly greater improvement in those herds where two footbaths were used (OR=3.39, CI: 2.07-5.19; P<0.001). Lesion improvement over time also increased with lactation number (OR=1.13, CI: 1.02-1.25; P<0.05).

Effectiveness of different footbathing frequencies using copper sulfate in the control of digital dermatitis in dairy cows.

Two experiments were conducted to test the effectiveness of different footbathing frequencies using CuSO4 in the control of digital dermatitis (DD) in groups of dairy cows with low and high DD prevalence in an endemically infected herd. During the study, groups of cows walked through allocated footbath solutions after milking on 4 consecutive milkings each week, 2 wk, or monthly, depending on treatment. The footbath solutions were changed either after 200 cows had passed through the footbath or within 24 h. All cows were scored weekly during milking for DD lesion stage on the hind feet using a 5-point nominal scale. A transition grade was assigned based on whether the DD lesions improved (1) or deteriorated or did not improve (0) from week to week, and was averaged for all cows in the group. Furthermore, from the longitudinal study data, all transitions between different DD lesion stages between the different time points were used in a discrete, first-order Markov chain (state transition matrix) model. In experiment 1, 70 Holstein-Friesian cows with DD lesions present on at least one of their hind feet were allocated to 1 of 2 footbath treatments for 14 wk: (1) 5% CuSO4 each week or (2) 5% CuSO4 every 2 wk. At the end of the study, no active DD lesions were observed in cows in either treatment group, but significantly more cows had no DD lesions (0.48 ± 0.097 vs. 0.24 ± 0.094) and fewer cows had lesions in the healing stage (0.52 ± 0.104 vs. 0.77 ± 0.090) for the weekly compared with the 2-wk footbathing regimen. The number of active DD lesions that the transition matrix model predicted over time was 3 and 8% for weekly and every 2 wk footbathing treatments, respectively. In experiment 2, 64 cows with no DD lesions on either of their hind feet were allocated to 1 of 2 footbath treatment regimens for 14 wk: (1) 5% CuSO4 every 2 wk or (2) 5% CuSO4 each month. At the end of the trial, significantly more cows had no DD (0.80 ± 0.088 vs. 0.65 ± 0.102) and fewer cows had DD lesions in the healing stage (0.20 ± 0.088 vs. 0.35 ± 0.102) in the every 2 wk regimen than in the monthly footbathing regimen. The number of active DD lesions that the transition matrix model predicted over time was low for both footbathing interventions (1 and 4%, respectively). Increasing the interval between footbaths does not appear the most appropriate mechanism for reducing CuSO4 usage.

Effectiveness of different footbath solutions in the treatment of digital dermatitis in dairy cows.

Three experiments were conducted to test the effectiveness of different footbath solutions and regimens in the treatment of digital dermatitis (DD) in dairy cows. During the study, groups of cows walked through allocated footbath solutions after milking on 4 consecutive occasions. All cows were scored weekly for DD lesion stage on the hind feet during milking. A "transition grade" was assigned on the basis of whether the DD lesions improved (1) or deteriorated or did not improve (0) from week to week. This grade per cow was averaged for all cows in the group. In experiment 1, 118 cows were allocated to 1 of 3 footbath treatments for 5 wk: (1) 5% CuSO(4) each week, (2) 2% ClO(-) each week, or (3) no footbath (control). The mean transition grade, and proportion of cows without DD lesions at the end of the trial were significantly higher for treatment 1 above (0.36, 0.13, and 0.11, respectively; standard error of the difference, SED = 0.057). In experiment 2, 117 cows were allocated to 1 of 4 footbath treatment regimens for 8 wk: (1) 5% CuSO(4) each week, (2) 2% CuSO(4) each week, (3) 5% CuSO(4) each fortnight, or (4) 2% CuSO(4) each fortnight. For welfare reasons, cows allocated to the weekly and fortnightly footbath regimens had an average prevalence of >60% and ≤25% active DD at the start of the trial, respectively. Significantly more cows had no DD lesions (0.53 vs. 0.36, respectively; SED = 0.049), and the mean transition grade of DD lesions was higher in the 5% compared with the 2% weekly CuSO(4) treatment (0.52 vs. 0.38, respectively; SED = 0.066). Similarly, significantly more cows had no DD lesions in the 5% compared with the 2% fortnightly CuSO(4) treatments (0.64 vs. 0.47, respectively; SED = 0.049). In experiment 3, 95 cows were allocated to 1 of 3 footbath treatments: (1) each week alternating 5% CuSO(4) with 10% salt water, (2) each week alternating 5% CuSO(4) with water, or (3) 5% CuSO(4) each fortnight (control). After 10 wk, more cows had no DD in the salt water treatment than in the control treatment (0.35 vs. 0.26, respectively; SED = 0.038), but levels of active lesions were higher for this treatment than in the other 2 treatments (0.17, 0.00, and 0.13, respectively; SED = 0.029). Treatment did not affect mean transition grade of DD lesions. In conclusion, CuSO(4) was the only footbath solution that was consistently effective for treatment of DD. In cases when DD prevalence was high, a footbath each week using 5% CuSO(4) was the most effective treatment.

The effect of pre-calving environment on the development of digital dermatitis in first lactation heifers.

Digital dermatitis is commonly reported to be most severe in first lactation heifers. It has been suggested that this initial infection is followed by the development of a limited immunity to the organisms which cause digital dermatitis. If this is the case then exposure to digital dermatitis prior to calving should reduce its severity after calving. A study was undertaken to examine whether such exposure significantly affected the development of digital dermatitis post-partum. Twelve weeks prior to calving, 60 Holstein heifers were blocked on the basis of their antibody titre to Borrelia burgdorferi and randomly allocated to one of three pre-calving environments: clean straw, used straw or cubicles. There was no significant effect of pre-calving environment on the development of digital dermatitis after calving indicating that "exposure" pre-calving did not reduce the development of digital dermatitis after calving. The most important factors determining the development of digital dermatitis after calving were presence of absence of visible lesions of digital dermatitis at Week-12 and at calving.

Treatment strategies for digital dermatitis for the UK.

Digital dermatitis is a worldwide disease causing lameness in cattle, especially when housed. Despite its widespread nature there are relatively few peer-reviewed articles providing experimental data concerning its treatment and control. At the risk of descending to anecdote, this review attempts to summarise the current state of knowledge. Three approaches to digital dermatitis treatment have been used: (1) systemic antibiotics, (2) individual topical treatment, and (3) mass topical therapy using a footbath. Systemic antibiotics have become a rare treatment because of their cost and perceived lack of efficacy. Individual topical treatment, mainly with antibiotic preparations, is the most commonly reported method. It is widely considered the treatment of choice by virtue of reliable information about efficacy, the advantage of precise targeting of antibiotic usage and the requirements of legislation. However, at least in the UK, mass treatment of digital dermatitis by foot bathing is commonly used on many farms. In some cases, for example with antibiotic footbath solutions, these treatments create legislative, health and safety and environmental difficulties. Despite the widespread use of many different treatments, there is a lack of good comparative data and the consequence is a very variable and somewhat anecdotal approach in the field. There is a pressing need for well-researched treatment strategies for different herd situations.

Effects of type of forage fed to dairy heifers: associations between claw characteristics, clinical lameness, environment and behaviour.

Heifers were reared separately on wet fermented (WF) (grass silage based) or dry unfermented (DU) (straw based) diets. Clinical lameness was recorded and physical claw attributes were measured regularly, up to six months after calving at approximately two years of age. Two months before calving, some aspects of animal behaviour and the properties of slurry were studied. The incidence of lameness due to claw horn lesions was significantly higher (P < 0.01) in WF than in DU. WF suffered more serious heel erosion prior to calving (P < 0.05) and had softer claw horn at two (heel and axial sole) out of five sites throughout (P < 0.01 and P < 0.05). The slurry produced by WF had lower total solids content (P < 0.05) and viscosity (P < 0.001). WF spent longer standing and feeding (P < 0.001). It is proposed that standing for longer in less viscous slurry contributed to softer claw horn and more severe heel erosion, predisposing WF to claw horn lesions causing lameness. Reducing contact with low dry matter slurry is recommended for improving claw health.

Effect of forage type on claw horn lesion development in dairy heifers.

In a continuous design study the claw health of 54 Holstein-Friesian heifer calves was recorded from three months of age until six months after first calving (30 months of age). Pre-calving heifers were either fed a wet, fermented grass silage-based diet (WF) or a dry, unfermented straw and concentrate based diet (DU), apart from grazing during their first summer. Approximately one month before calving both groups were fed a silage-based diet and afterwards all received a silage and concentrate lactation ration. Claws were examined four times during rearing, once pre-calving, and four times during lactation. Both white line and sole lesions were significantly worse for WF than DU both during rearing and throughout first lactation although the effect was not as consistent over time for white line lesions. It is concluded that for optimal claw health youngstock diets should not be heavily based on wet grass silage (less than 25% DM).

A systematic compilation and classification of the literature on lameness in cattle.

This paper presents the first systematic review of the literature on lameness in cattle. It identifies, tabulates and classifies relevant published work and was conducted using electronic reference databases (BIDS ISI, BIOSIS, MEDLINE and the CAB Abstracts CD-ROM). A total of 1373 unique references were obtained from 1981 to 2000, of which 914 were written in the English language. A written search protocol was designed to ensure transparency and repeatability. Pilot studies were undertaken to create search terms that minimised bias and ensured relevance. Electronic files of the search terms allow the database to be updated in future. A further 93 references were included from the most recent international conference on lameness giving a total of 1007 English language references. The systematic review process is described, including a method of classifying papers according to their study design and statistical analysis, and it is hoped that other veterinary researchers will conduct similar reviews in their fields. The compiled and classified references are available as a searchable database through the web-sitehttp://cattle-lameness.dhs.org/. The review may be used in several ways; to identify practical interventions to reduce lameness in dairy cows and to use the resultant web-site as the basis of a decision support system for farmers, veterinarians and advisors.

Effects of time of year and reproductive state on the proliferation and keratinisation of bovine hoof cells.

Cell proliferation and protein synthesis (keratinisation) were measured in vitro in hoof biopsy samples taken from two groups of seven heifers, the first calving in the winter and the second in the summer. Both parameters were significantly higher in summer than in winter irrespective of the heifers' reproductive state. The mean (se) measure of the rate of protein synthesis was 199 (27) dpm/microg DNA/hour in summer and 4 (1) dpm/microg DNA/hour in winter, and the equivalent values for cell proliferation (measured as DNA synthesis) were 375 (56) dpm/microg DNA/hour and 17 (4) dpm/microg DNA/hour. Changes around parturition depended on the time of the year. In the winter-calving heifers, the rates of proliferation and keratinisation increased significantly after calving from 22.3 (7.2) to 70.4 (16.6) and from 2.1 (0.7) to 12.4 (2.8) dpm/microg DNA/hour, respectively. In the summer-calving heifers, proliferation decreased from 388.2 (91.0) to 66.7 (9.6) dpm/microg DNA/hour but the rate of keratinisation did not change. Lesion scores and locomotion scores deteriorated after parturition, especially in the winter-calving group. The hooves were harder in summer than winter but their hardness was not affected by the heifers' reproductive state.

The effect of feeding grass silage in early pregnancy on claw health during first lactation.

Two groups of eight Holstein-Friesian heifers were fed either a grass-silage-based diet (S) or one based on meadow hay supplemented with 1.8 kg/day barley concentrate mix (H) during cubicle housing as young stock (and in early pregnancy). Lameness and claw lesion development were monitored from approximately four weeks before until 20 weeks after first calving. No significant difference was found between S and H for claw conformation or horn growth and wear. Both groups showed net wear immediately after calving. The prevalence of poor locomotion and the extent of lesion development 20 weeks after calving (when they were highest) were significantly (P< 0.05) higher in S than H. It was concluded that feeding grass silage to young stock may deleteriously affect subsequent claw health and that this risk factor requires further study.

Correlations of measurements of subclinical claw horn lesions in dairy cattle.

Measurements were made of the extent of sole and white line lesions on the claws of 115 Holstein-Friesian cows on at least three and at most 16 occasions, and some cows were followed up to their third lactation. All the measurements were made between 12 weeks before calving and 45 weeks after calving. In total, 1016 repeated observations were made. Correlations were calculated between pairs of claws, between types of lesion (sole and white line), and between pairs of the different measurements (number of lesions, proportion of the claw affected, maximum severity score and proportion of the claw affected weighted for severity). The outer hind claws had the greatest extent of lesions of both types. Spearman correlation coefficients and confidence intervals measured the strength of the association. All the associations between claws were positive, suggesting that the lesions did not occur in isolation. Sole and white line lesions were not associated at individual observation points. Lesions on the left and right claws were markedly similar, except for sole lesions on the two inner hind claws, and for white line lesions on the two outer hind claws.

Observations of lameness, hoof conformation and development of lesions in dairy cattle over four lactations.

Lameness and lesions in the claws of 31 autumn-calving Holstein Friesian dairy cows were recorded from before their first-calving until their fifth lactation. The animals were managed by the same herdsman and housed adjacently in the same building in one of two herds grazed either on clover-rich pastures (herd 1) or on conventional ryegrass (herd 2). All four hooves were examined routinely four times during each lactation, and claw lesions were scored for severity and drawn on hoof maps. Heel erosion and infectious skin conditions of the hoof were also recorded, and hoof conformation, hardness, and growth and wear were measured. The animals' locomotion was scored weekly throughout the winter housing period and any observed to be lame were examined to determine the cause. The development of lesions was modelled by using hierarchic smoothing splines. There was no significant effect of herd except on the prevalence of lameness in lactation 2 when the incidence of (inter)digital dermatitis was higher in herd 2. Lesion and locomotion scores were significantly higher by lactation 4 (P<0.05). There were significant effects (P<0.05) of weeks postcalving on lesion formation, claw conformation, and heel erosion.