Study on the effect application of Digiderm+ in comparison with formalin 4% on Digital Dermatitis (Mortellaro disease) in dairy cows.
GD Deventer: Dr. M. Holzhauer, Dr. C. J. Bartels, and Dr. T.J.G.M. Lam
WUR Wageningen: Ir. M. van ’t Riet and Dr. Ir. K. Frankena
Introduction Digital Dermatitis or Mortellaro disease (DD) is the most important infectious claw disorder in dairy
cows in Western Europe. DD has economical consequences (among others decreased milk production), affects animal welfare (M2 stage of DD is very painful especially) and DD affected
dairy cows disturb the normal daily routine of the dairy farmer (cows have to be separated and treated individually). Moreover, a clear relationship with interdigital dermatitis/heel horn erosion
has been estimated, whereby it remains unclear if the HHE is a consequence or a causing factor of DD. In order to prevent these problems, milking cows are foot bathed (bi-) weekly in a large part
of the Dutch dairy herds. Most products used nowadays, such as formalin, are known to have harmful effects on the health of users/milkers and the environment. New products (based on
modern disinfectants without or with a much lower concentration of heavy metals) have been developed. One of these is Digiderm+, whereby the presumed effect is based on a low pH and a strengthening effect of the disinfection by the addition of CuSO4. The aim of this clinical trial was to study both the preventive and the curative effects of Digiderm+ (Digiderm™ and 2% copper sulphate) against DD in comparison with formalin 4% during
Material and methods The field study has been performed at a commercial Dutch dairy farm with on average 120 dairy
cows (Holstein Frisians, production level 8700 kg milk per lactation, with on average 4.25% milk fat and 3.45% milk protein and pasturing) and serious DD problems (percentage dairy cows affected with DD at the start of the study 19%; normal prevalence in the Netherlands < 10%). At
the farm the milking cows were weekly foot bathed, generally with formalin 4% and once in a while with copper sulphate.
During a 4 months period (September 2009 – January 2010) the lactating cows were foot bathed every week through a left/right split foot-bath, on the left side filled with Digiderm+ (foot bathed 5
days/week) and the right side a formalin 4% solution foot bathed during 1 day every second week (according to the current standard advise in the Netherlands). At the start of the study and
subsequently every 4 weeks the hind claws were scored in a trimming chute for both, presence and severity of DD and heel horn erosions (HHE) by a trained student. Serious M2 lesions were
promptly treated topically with a tetracycline spray (CTC, Eurovet, NL). Based on these recordings a distinction could be made between the curative effects on lesions present and the preventive effect on new infections. This distinction was important to quantify both the curative (1-
persistency) and preventive effect (new infections) of Digiderm+ and formalin 4%.
The recorded data were analysed with modern statistical analysis techniques. First of all, a survival analysis with Cox proportional hazard regression has been applied. Hereby the risk for getting a
new M2 lesion and the risk of being cured of a present M2 lesion is analysed separately, during intervention with Digiderm+ in comparison with formalin 4%. In both situations (infection and cure) only the first cases are part of the analysis. In case of a second “new” M2 lesion (reinfection),
this case was not taken into account. Moreover, a transitional logistic regression has been applied. Hereby, the scores on day x were
related to the previous score (day x minus 30) based on Generalized Linear Mixed Model (GLMM). This model has been corrected for dependency for repeated observations on the same cow
(repeated measures). The unit of analysis was the hind leg (left or right) with the primary outcome being the presence or absence of serious DD (M2-lesion). Overall, the average size of included
Results and discussion The DD prevalence (= no. cows with one or two hind claws with M2 lesions) at the start of the study was 19.1%, with 13 lesions on the left and 11 on the right side. Of the cows affected, 3 had
M2 lesions on both hind claws. At the end of the study (n=106 cows) the prevalence was 16.0%, 3 cows left (Digiderm+), and 14 on the right side (formalin), with 0 cows with both hind claws
Table 1. Prevalence of digital dermatitis scored on the different days of observation (September 2009 – January 2010).
*on D30 there are 6 claws with M2 lesions registered in left hind legs. The observations before
(D0), there were 13 M2 lesions, of which 9 cured and there were 2 new M2 lesions registered (6 = 13 – 9 + 2).
** in these situations the numbers don’t add up which is caused by cows that were introduced and
already had an M2 lesion, but were not counted as a new M2 lesion, since there was no information
on their previous DD status. Based on the survival analysis the hazard (risk) for a new M2 lesion on hind legs walking through
the Digiderm+ footbath was 0.37 (95% confidence interval 0.16-0.91) time the risk for a new M2 lesion on hind legs walking through a formalin 4% footbath (see also Fig. 1). In other words, the
risk of getting a M2 lesion on the Digiderm+ hind leg was (1/0.37)= 2.7 times lower than when walking through formalin 4%.
A strong effect of ID/HHE on the risk of getting a M2 lesion was found, the risk of M2 lesion was 3 times higher than in absence of ID/HHE. This effect of ID/HHE was not influenced by the use of
No difference in curative effect could be found between formalin 4% and Digiderm+. The hazard ratio was 1.5 (P value: 0.23; see also Fig. 2).
Figure 1. Kaplan-Meier estimation of the survival analysis for the effect of Digiderm+ and formalin
4% on the risk of getting new M2 lesions on the hind claws. The plot shows the percentage of claws not having M2 lesions.
Figure 2. Kaplan-Meier estimation of the survival analysis for the effect of Digiderm+ and formalin
4% on the cure of M2 lesions on the hind claws. The plot shows the percentage of M2 lesions that do not cure.
The results of the logistic regression show a comparable result as the survival analysis. Estimating
the risk of a new M2 lesion with formalin 4% was 0.04 for the period between 2 observations (30 days), which was significantly lower when using Digiderm+ (0.01; P= 0.01). The risk of curing a
M2 lesion was (1-0.38=) 0.62 when treated with formalin 4% and (1-0.55=) 0.45 when treated with Digiderm+. These differences were statistically not significant (see table 2).
Table 2 Risk of new M2 lesion and risk of cure of present M2 lesions by intervention of Digiderm+ compared with formalin 4% and estimated by transitional logistic regression analysis.
Risk of new infection (per period of 30 days)
This clinical trial on the influence of Digiderm+ on the prevention and cure of DD is supplementary
to a study in an experimental herd in Sweden, where the same product was compared with water. In the Swedish study also the Digiderm+ treated group had a significantly decreased DD
prevalence (Bergsten, 2008). In a recent Danish study of 8 weeks duration, that was executed in 12 different dairy herds, different multi-compound products like glutaraldehyde (Virocid), organic acids (Kickstart 2), and quaternare ammonium compounds (Hoofcare DA)) were compared with a
negative control (water) (Thomsen et al., 2008). These products were applied for 2 consecutive days each week, without any effect on DD prevalence (without discriminating between prevention
and cure). The period of intervention, however, may have been too short. Based on our experiment, it seems advisable to use a foot-bath frequency of 3-5 days per week.
Further studies with products like Digiderm+ are advisable; especially studies on treatment frequencies in herds with low DD prevalence are desirable to minimize extra costs, environmental
pollution and labour of the dairy farmer. Conclusion The use of Digiderm+ compared with formalin 4% resulted in a 2.7 fold reduction of the incidence of new DD M2 lesions. The curative effect of Digiderm+ on existing DD infections did not differ
Acknowledgement Fam. Mogezomp (dairy farmer),and the claw trimmers of AB-Oost are acknowledged for their kind
cooperation and punctual work during this clinical trial.
References Bergsten, C. 2008. Report on foot bathing with an acidulated solution (Healthy Hooves™) with 2%
copper sulphate on the prevalence if digital dermatitis and heel horn erosion. Internal report SLU.
Thomsen PT, Sørensen JT and Ersbøll AK. 2008. Evaluation of three commercial hoof-care products used in footbaths in Danish dairy herds. J. Dairy Sci. 91:1361-1365.
O R I G I N A L C O N T R I B U T I O N Continuous Versus Intermittent Nebulizationof Salbutamol in Acute Severe Asthma: Lamia Besbes-Ouanes, MD* See editorial, p. 236. Semir Nouira, MD* Souhail Elatrous, MD‡ Study objective: This study was conducted to compare the Jalel Knani, MD* clinical and spirometric effects of continuous and intermittent Mohamed Boussarsar, MD* Oc
Allergeni per Sistemi Phadia® La diagnostica allergologica in vitro proposta da Phadia è il sistema più diffuso ed utilizzato a livello mondiale per la determinazione quan-titativa delle IgE Specifiche; basato sulla tecnologia ImmunoCAP® è stato il primo metodo calibrato contro il 2° Standard Internazionale di Riferimento WHO 75/502 per le IgE umane. I risultati quantitativi sono espres
No difference in curative effect could be found between formalin 4% and Digiderm+. The hazard ratio was 1.5 (P value: 0.23; see also Fig. 2).
Figure 1. Kaplan-Meier estimation of the survival analysis for the effect of Digiderm+ and formalin
4% on the risk of getting new M2 lesions on the hind claws. The plot shows the percentage of claws not having M2 lesions.
Figure 2. Kaplan-Meier estimation of the survival analysis for the effect of Digiderm+ and formalin
4% on the cure of M2 lesions on the hind claws. The plot shows the percentage of M2 lesions that do not cure.
The results of the logistic regression show a comparable result as the survival analysis. Estimating
the risk of a new M2 lesion with formalin 4% was 0.04 for the period between 2 observations (30 days), which was significantly lower when using Digiderm+ (0.01; P= 0.01). The risk of curing a
M2 lesion was (1-0.38=) 0.62 when treated with formalin 4% and (1-0.55=) 0.45 when treated with Digiderm+. These differences were statistically not significant (see table 2).
Table 2 Risk of new M2 lesion and risk of cure of present M2 lesions by intervention of Digiderm+ compared with formalin 4% and estimated by transitional logistic regression analysis.
Risk of new infection (per period of 30 days)
This clinical trial on the influence of Digiderm+ on the prevention and cure of DD is supplementary
to a study in an experimental herd in Sweden, where the same product was compared with water. In the Swedish study also the Digiderm+ treated group had a significantly decreased DD
prevalence (Bergsten, 2008). In a recent Danish study of 8 weeks duration, that was executed in 12 different dairy herds, different multi-compound products like glutaraldehyde (Virocid), organic acids (Kickstart 2), and quaternare ammonium compounds (Hoofcare DA)) were compared with a
negative control (water) (Thomsen et al., 2008). These products were applied for 2 consecutive days each week, without any effect on DD prevalence (without discriminating between prevention
and cure). The period of intervention, however, may have been too short. Based on our experiment, it seems advisable to use a foot-bath frequency of 3-5 days per week.
Further studies with products like Digiderm+ are advisable; especially studies on treatment frequencies in herds with low DD prevalence are desirable to minimize extra costs, environmental
pollution and labour of the dairy farmer. Conclusion The use of Digiderm+ compared with formalin 4% resulted in a 2.7 fold reduction of the incidence of new DD M2 lesions. The curative effect of Digiderm+ on existing DD infections did not differ
Acknowledgement Fam. Mogezomp (dairy farmer),and the claw trimmers of AB-Oost are acknowledged for their kind
cooperation and punctual work during this clinical trial.
References Bergsten, C. 2008. Report on foot bathing with an acidulated solution (Healthy Hooves™) with 2%
copper sulphate on the prevalence if digital dermatitis and heel horn erosion. Internal report SLU.
Thomsen PT, Sørensen JT and Ersbøll AK. 2008. Evaluation of three commercial hoof-care products used in footbaths in Danish dairy herds. J. Dairy Sci. 91:1361-1365.