Evaluation of a biocide footbath solution in the occurrence and healing of digital dermatitis lesions in dairy cows: A clinical trial.

The objective of this study was to evaluate the effect of the implementation of different footbathing practices using a new biocide solution (Pink-Step™, Qalian, France) in the healing and the occurrence of bovine digital dermatitis (bDD) lesions. The investigation was conducted through a controlled within cow clinical trial in which the hind feet of cows from each farm were allocated either to the control group or to a moderate (MR) or (IR) intensive footbath-regimen groups. The trial involved 1036 cows (2072 feet) from 10 dairy farms located in western France where bDD was endemic. Split-footbaths were placed at the exit of the milking parlor of each farm, allowing the biocide to be administered to one side of the cows while using the other empty side as a negative control. The administration frequency for MR was of 2 days/week/1st-month, then 2 days/2 weeks/2nd-month, and then 2 days/month, and for IR was of 2 days/week/1st-2nd months, and then 2 days/2 weeks. Footbaths were administered during 140 days (approx.), and feet were evaluated for the at least once a month in the milking parlor. Nested survival models were used to estimate the relative impact of the footbath regimens and other concomitant risk factors on the time that bDD lesions occurred or healed. No effect of Pink-Step™ was evidenced on the bDD occurrence during the trial. The risk for bDD occurrence was increased by poor feet cleanliness at both the cow (HR 1.69, CI 1.21-2.39) and farm level (HR 2.06, CI 1.44-2.94). Otherwise, the use of Pink-Step™ in an IR was effective in improving the healing of bDD lesions (HR 1.79, CI 1.12-2.88). The time to healing was also improved in inactive lesions (HR 2.19, CI 1.42-3.37). Conversely, the time to healing was delayed in feet receiving hoof-trimming (HR 0.41, CI 0.26-0.62), in cows with a contralateral bDD lesion (HR 0.32, CI 0.22-0.46) or in late lactation (HR 0.61, CI 0.43-0.85), and finally in farms with more than 100 cows (HR 0.48, CI 0.34-0.67). These findings reinforce the crucial role of hygiene in bDD dynamics and highlight the importance of implementing multiple control measures simultaneously, such as hygiene improvements in the barn, early detection and treatment of bDD lesions and the correct usage of individual and collective treatments. The implementation of Pink-Step™ represents a promising strategy for reducing the persistence of bDD lesions in affected herds.

Efficacy of a commercial glutaraldehyde footbath product for the control of bovine digital dermatitis.

OBJECTIVE: To evaluate the relative efficacy of a novel, commercially available disinfecting agent containing ≥ 15 to < 20 % glutaraldehyde in a hydro-colloid matrix ("EIMÜ Klauen Sprint®"; Eimermacher, Nordwalde, Germany, Biozid-Desinfektionsmittel, BAuA Nr. N-57213) as a walkthrough footbath in order to treat digital dermatitis of dairy cattle. MATERIAL AND METHODS: The study was conducted in a dairy farm located in northern Germany from June 1st, 2015 to September 5th, 2015. Eighty-eight cows were enrolled in this study. In both trials of the study, a walkthrough footbath was applied on five consecutive milking times per week. Trial 1 was a blinded, randomised and controlled intervention study. The therapy group (n = 40) received the novel glutaraldehyde product in a 2 % solution while the control group (n = 40) was led through a footbath containing pure water. Trial 2 was a longitudinal study to investigate the development of claw health over a longer time period regarding the use of the new footbath solution. In trial 2 the disinfecting footbath was applied to all trial cows (therapy and control group) of trial 1. The development of claw health and lameness was systematically monitored in the two groups on days 0, 9, 17, 29, 35 (trial 1) and days 42, 68, 94 (trial 2), respectively. The adjusted odds of digital dermatitis lesions (DDL) throughout the study were analysed by mixed logistic regression models. RESULTS: The odds of DDL were 0.15 for the glutaraldehyde foot-bath group compared to the control group. Hence, the disinfecting footbath significantly reduced the DDL prevalence and increased the cure rate of DDL. However, no preventive effect on new digital dermatitis (DD) cases could be identified. CONCLUSION: The efficacy of the novel glutaraldehyde footbath was evaluated and it was concluded that "EIMÜ Klauen Sprint®" was well tolerated over a longer period of time and might therefore be an effective tool to control DD. CLINICAL RELEVANCE: In future, "EIMÜ Klauen Sprint®" could be used within a Mortellaro sanitation concept and thereby might help to solve a major problem of dairy cattle farms.

Comparison of the efficacy of a commercial footbath product with copper sulfate for the control of digital dermatitis.

Digital dermatitis (DD) is the most prevalent foot lesion affecting dairy herds worldwide. Its implications include production losses and decreased animal welfare. Footbathing is the most common herd-level prevention strategy for DD. Because many common footbath products have negative environmental and health consequences, replacement products expected to have improved safety but equal efficacy are being developed. Therefore, the aim of this study was to evaluate the efficacy of a new quaternary ammonium-based commercial footbath product (QAC) for reducing the prevalence of active DD lesions compared with an industry standard (copper sulfate; CuSO4) and typical on-farm footbath practices. A controlled intervention trial was conducted on 19 Alberta dairy farms over 12 wk, with 9 farms allocated to the QAC group (1% QAC daily, 5 d/wk), 5 to the CuSO4 group (5% CuSO4 daily, 5 d/wk), and 5 to a noninterference group (maintained typical footbath practices). A total of 22,285 observations on 3,465 lactating cows were assessed for DD lesions and leg cleanliness in the milking parlor. Five farms discontinued use of the QAC product for various reasons. Noninferiority analysis was used to assess QAC ability to decrease the proportion of cows with 1 or more active DD lesions compared with CuSO4 after 6 wk. Multilevel logistic regression models for repeated measures were used to evaluate efficacy of QAC compared with CuSO4 and noninterference farms in reducing the prevalence of active DD lesions at the foot level over 12 wk. The noninferiority analysis determined that the proportion of cows with 1 or more active DD lesion decreased 2.19 (95% CI: 1.39-3.46) times less after 6 wk of study on the QAC farms compared with CuSO4 farms, making QAC inferior to CuSO4. The multilevel logistic regression models determined that the proportion of active DD lesions increased in the QAC herds, whereas this proportion decreased in the CuSO4 and noninterference herds over 12 wk. Additionally, cows in mid- and late-lactation had a higher odds of having active DD compared with fresh cows. Older cows (parity 3 and ≥4) had a decreased odds of active DD compared with first-parity cows. At the farm level, a higher baseline active DD prevalence resulted in increased odds of active DD; however, this did not modify the effect of treatment or week of study. We concluded that QAC was inferior to CuSO4 and typical on-farm footbath practices, and further development of novel footbath products is required to develop an ideal alternative.

Pseudomonas aeruginosa mastitis in two goats associated with an essential oil-based teat dip.

Pseudomonas aeruginosa is an opportunistic pathogen that has been associated with mastitis in dairy animals, including goats. Often, the environmental sources of the bacteria are water-related (such as hoses and muddy pastures). Mastitis attributable to P. aeruginosa was identified in 2 goats in a small herd. Efforts were made to identify environmental sources of the pathogen. Multiple samples from the goats' environment were cultured, including water from the trough, bedding, the hose used to wash udders, and the teat dip and teat dip containers. The bacterium was isolated from the teat dip and the teat dip container. The teat dip consisted of water, liquid soap, and several drops of essential oils (including tea tree, lavender, and peppermint). This case illustrates a potential problem that may arise as a result of the use of unconventional ingredients in teat dips. The use of alternative products by goat producers is likely to increase in the future.

Development and evaluation of a protocol for control of Giardia duodenalis in a colony of group-housed dogs at a veterinary medical college.

OBJECTIVE To develop and evaluate a protocol for control of Giardia duodenalis in naturally infected group-housed dogs at a veterinary medical college. DESIGN Prospective evaluation study. ANIMALS 34 dogs. PROCEDURES All dogs were tested for evidence of G duodenalis infection. Dogs were treated with fenbendazole on study days 1 through 10. On day 5, dogs were bathed and moved into clean, disinfected kennels in a different room to allow for disinfection and drying of their assigned kennels at 26.7°C (80°F) for 24 hours on day 6. After treatment, dogs were returned to their original housing; fecal samples were collected weekly from days 8 through 41 and then every 3 weeks until day 209. Samples were fixed in formalin and examined by direct immunofluorescence assay. Additionally, 1 pretreatment sample underwent PCR assay and DNA sequencing to determine the assemblage (genotype) of the organism. Normal handling routines for the dogs and their use in teaching activities were not changed. RESULTS Initially, all dogs in the colony shed G duodenalis cysts. During and immediately after treatment (days 8 and 13), no cysts were detected in any dogs. On day 20, 1 cyst was observed in the fecal sample from 1 dog; results for all subsequent fecal analyses were negative. The G duodenalis cysts collected from the pretreatment sample had an assemblage C genotype. CONCLUSIONS AND CLINICAL RELEVANCE The integrated protocol was successful in controlling G duodenalis infection in this dog colony, despite exposure of dogs to a variety of environments and frequent handling by multiple individuals. Sequence analysis identified an assemblage typically found in dogs but not in people, indicating that zoonotic transmission would be unlikely.

Effect of a tea tree oil and organic acid footbath solution on digital dermatitis in dairy cows.

Copper sulfate is the industry gold standard footbath ingredient for controlling dairy cow digital dermatitis. However, when used footbath solutions are deposited on soil, high levels of copper in the soil may result, which can have toxic and negative effects on plant growth. An alternative to copper sulfate is Provita Hoofsure Endurance (Provita Eurotech Ltd., Omagh, UK), which is a biodegradable solution containing organic acids, tea tree oil, and wetting agents. The objective of this study was to quantify changes in digital dermatitis frequency when using Provita Hoofsure Endurance and copper sulfate in a split footbath in 3 commercial dairy herds. This study was conducted from January 5, 2012, to March 19, 2012, in 3 commercial Kentucky dairies with 120, 170, and 200 milking Holstein cows. None of the herds was using a footbath for digital dermatitis control before the study. Footbath solutions were delivered using a split footbath. During the study, a 3% Hoofsure Endurance solution for the left hooves and a 5% copper sulfate solution for the right hooves was used. Digital dermatitis was scored every 3wk using the M0 to M4 system, where M0=a claw free of signs of digital dermatitis; M1=a lesion <2cm that is not painful; M2=the ulcerative stage, with lesion diameter of >2cm, and painful to the touch; M3=the healing stage and covered by a scab; and M4=the chronic stage and characterized by dyskeratosis or proliferation of the surface that is generally not painful. McNemar's test statistic suggested that a statistically significant difference existed in the proportions of M1 and M2 lesions between the beginning and end of the study for both treatments. This indicates that each solution was effective in decreasing the proportion of M1 or M2 lesions from baseline to the last time point. A chi-square test calculated using PROC FREQUENCY of SAS (SAS Institute Inc., Cary, NC) indicated that no statistically significant relationship existed between the treatments among changes in digital dermatitis frequency from the baseline to the end of the study. Performance of the 2 footbath solutions was comparable throughout the study. No significant differences were observed between the copper sulfate and Provita Hoofsure Endurance.

[Influence of a new biocidal product on the prevalence of digital dermatitis in dairy cows]. / Einfluss eines neuartigen Biozids auf die Prävalenz von Dermatitis digitalis bei Milchkühen.

OBJECTIVE: It was investigated whether usage of the biocidal product T-Hexx Dragonhyde (Hydromer, Branchburg, NJ, USA) could influence the prevalence of digital dermatitis (DD). MATERIAL AND METHODS: On a dairy farm (110 milking cows) 48 dairy cows without lameness were selected randomly for a test group or a control (negative) group, respectively. A high prevalence of DD (70-80%) was documented over a period of 2 months, during which four examinations were made, with an interval of 16-21 days between each examination. The respective grade of the DD-lesion on the hind hoofs was documented according to a scoring scheme. After precleaning the claws with water, the test group passed through a hoof bath containing T-Hexx Dragonhyde on 2 days per week at two milking times on each day, whereas the claws of control animals were cleaned using only a water bath. Splashes contaminating the animals and the environment were documented photographically and evaluated. Bacteriological examinations of the water bath and the T-Hexx-bath were performed after increasing numbers of animals had passed through the baths. RESULTS: Between and within groups no statistically significant differences in the prevalence of DD were found. DD-lesion scoring did not show any difference between the groups. With increasing numbers of animals having passed through the water bath, there was a significant increase in colony-forming units per millilitre and of enterobacteriaceae. In the T-Hexx Dragonhyde footbath, bacterial contamination remained below the detection limit at all times. The coloured splashes of the footbath were visible up to the level of the udder and teats. CONCLUSION AND CLINICAL RELEVANCE: The prevalence of DD was not influenced by the 2% or 4% concentration of the biocidal product in the footbath. Thus the microbiocidal effect of the solution did not lead to an efficient reduction in bacteria on the hoof. To demonstrate a potential preventive effect on DD, future studies would require herds with lower prevalence and a higher sample size. However, when applying footbaths there is the general risk of milk contamination or causing mastitis.

Efficacy of bath and orally administered praziquantel and fenbendazole against Lepidotrema bidyana Murray, a monogenean parasite of silver perch, Bidyanus bidyanus (Mitchell).

We investigated the efficacy of praziquantel (PZQ) and fenbendazole (FBZ), each administered by bath and orally, against the monogenean Lepidotrema bidyana Murray, a gill parasite of the freshwater fish silver perch, Bidyanus bidyanus (Mitchell). PZQ and FBZ were each administered by bath at 10 mg L⁻¹ for 48 h and on surface-coated feed pellets at 75 mg kg⁻¹ per body weight (BW) per day for 6 days. Bath treatments of PZQ and FBZ had an efficacy of 99% and 91%, respectively, against adult L. bidyana. Oral treatments of PZQ and FBZ had an efficacy of 79% and 95%, respectively, against adult L. bidyana. Fish rejected feed pellets surface-coated with PZQ, suggesting that palatability of surface-coated PZQ-medicated feed is poor, which undermined efficacy. In all trials, some juvenile parasites were present on fish after treatment during efficacy assessment, indicating that efficacy may be lower against juvenile parasites or that recruitment occurred post-treatment, demonstrating that repeat treatments are necessary to effectively control L. bidyana in aquaculture.

Estimation of the relative impact of treatment and herd management practices on prevention of digital dermatitis in French dairy herds.

The purpose of this study was to concurrently estimate the effect of different digital dermatitis (DD) treatment regimens and herd management practices on the occurrence of a new DD lesion. A controlled clinical trial was conducted and involved 4678 dairy cows from 52 French dairy farms where DD was endemic. Farms were allocated by minimisation to one of 4 treatment regimens, varying through the mode (footbath or collective spraying) and the frequency of application (2 days every 4 weeks or fortnightly). They were visited 7 times every 4 weeks by 14 trained investigators. Frailty Cox proportional hazards models were used to estimate the relative effect of potential risk factors and treatment practices on the time until the first occurrence of a DD lesion. At herd level, high initial DD prevalence strongly increased the risk for DD occurrence (HR=1.93, CI 1.23-3.04), as well as absence of hoof-trimming (HR=1.75, CI 1.36-2.27) and poor leg cleanliness (HR=2.44, CI 1.80-3.31). At animal level, Holstein breed (HR=1.92, CI 1.35-3.57) and high-productive cows (HR=1.26, CI 1.01-1.56) were identified to be at higher risk for DD compared to Normande breed and low-productive cows, respectively. Compared to individual topical antibiotic treatments alone, collective treatments tended to decrease the risk of DD occurrence only when applied over 2 days at least every fortnight (HR range=0.64-0.73).

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).

The effect of an acidified, ionized copper sulphate solution on digital dermatitis in dairy cows.

Digital dermatitis (DD) is the most important infectious claw disorder in dairy cattle and herd-based foot bathing with antibacterials, such as 4% formalin, is often used to prevent it. However, there is a lack of long-term studies of the effectiveness of such regimes and in this study the preventive and curative effect of 4% formalin was compared with that of an acidified, ionized copper sulphate solution over a 4-month period on a commercial 120-cow dairy farm. The cows were walked through a split-leg footbath where left claws were treated with an acidified copper solution twice daily for 5 days/week, while right claws were treated with 4% formalin twice daily for 1 day/every second week. Hind claws were scored for the presence and severity of DD in a trimming chute at the start of the study and every 4 weeks throughout the study period. At the start of the study 21/110 cows had ulcerative DD lesions with 10 on the left hind foot, 8 on the right and 3 on both. These lesions, as well as any new lesions which arose during the study, were treated with chlortetracycline spray. During the study 440 observations were made and seven new DD lesions were recorded on left feet (copper treated) and 20 on right feet (formalin treated). Based on survival analysis, the risk of developing a new ulcerative DD lesion on copper-treated (left hind) feet was almost three times less (RR=0.37, 95% CI 0.16-0.91) than formalin-treated (right hind) feet. Cure rates of DD lesions were not different between copper and formalin.

Long-term observations on the dynamics of bovine digital dermatitis lesions on a California dairy after topical treatment with lincomycin HCl.

The objective of this study was to observe the dynamics of clinical cure and recurrence of the lesions of bovine digital dermatitis for 11 months after treatment with topical lincomycin HCl. The study was a clinical follow-up of 39 active bovine digital dermatitis lesions (from 29 cows). Cows with active, painful bovine digital dermatitis (BDD) lesions on the interdigital commissure of the rear feet were identified on day 0. On day 1, lesions in all cows were photographed and full-skin thickness 6mm punch biopsies were obtained for histological evaluation. All lesions on all cows were treated with topical lincomycin paste under a light bandage. On days 12 and 23, a subsample of 10 lesions was randomly selected, photographed, and biopsied. On day 37, all lesions on all cows were photographed and biopsied. After day 37, lesions were evaluated on a monthly basis. All lesions were photographed at each observation until day 341 (end of study) but only cows that had macroscopically active lesions were biopsied. Of the 39 lesions treated on day 1, 21 (54%) required re-treatment on at least one occasion before day 341. Macroscopic classification agreed well with histological classification when lesions were small, focal and active (M1 lesions) or large, ulcerative and active (M2), but agreement was variable for lesions that had healed macroscopically (M5) or that were chronic (M4). A transition model showed that M1 and M2 lesions were 27 times more likely to be an M2 lesion on the next observation than to be a healed (M5) lesion.

The dynamics of digital dermatitis in populations of dairy cattle: model-based estimates of transition rates and implications for control.

Five groups of dairy cows affected by digital dermatitis were subjected to five different footbath strategies and evaluated at regular 3-weekly intervals. A standard protocol was used to record five different stages of disease from early (M1), acute ulcerative (M2), healing (M3) and chronic lesions (M4) in addition to the negative stage of disease (M0). The effect of the footbathing was evaluated using mathematical modelling for the transmission dynamics of infections and summarized using the reproduction ratio R(0). Sensitivity analysis for a range of parameters in the mathematical model showed that the speed of detecting acute lesions and the efficiency with which those lesions were treated were the key parameters which determined whether lesions became more severe or whether they healed.

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.

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.