Comparison of clinical cure rates from footrot and contagious ovine digital dermatitis using zinc sulphate foot bathing and topical oxytetracycline: A randomised trial.

BACKGROUND: This study reports the clinical cure rates of topical oxytetracycline and 10% zinc sulphate foot bathing for treatment of interdigital dermatitis (ID), footrot (FR) and contagious ovine digital dermatitis (CODD) in lambs. METHODS: The study was a randomised controlled trial of 75 lambs. Group A (n = 38) was foot bathed daily for 5 days in 10% zinc sulphate for 15 minutes and group B was treated with daily topical oxytetracycline for 5 days. On days 0, 7, 14, 28 and 42, lambs were scored for locomotion and foot lesions were recorded. RESULTS: The initial cure rates for ID were 96.20% and 97.00%; for FR, 100% and 95%; and for CODD, 90.09% and 83.33% for zinc sulphate and oxytetracycline, respectively. By day 42, these had changed to 53.16% and 61% for ID; 47.82% and 70% for FR; and 100% and 83.33% for CODD. There were no significant differences in cure rates between the treatments for most time points. LIMITATIONS: The sample size was small, and further studies in larger cohorts and different classes of sheep are required before the findings can be translated into recommendations for clinical practice. CONCLUSION: Both treatments achieved cure rates that are comparable to reported cure rates using systemic antibiotics and could be an effective alternative.

[First case description of contagious ovine digital dermatitis in Switzerland]. / Erstbeschreibung der Krankheit «Kontagiöse ovine digitale Dermatitis¼ in der Schweiz.

INTRODUCTION: Contagious ovine digital dermatitis (CODD) is an emerging infectious foot disease in sheep. To date, CODD has been described in Great Britain, Ireland, Sweden and Germany and now in Switzerland for the first time. Unlike foot rot, the CODD lesions do not spread from the interdigital space, but usually begin at the dorsal/abaxial coronary band. The changes can spread to the hoof wall and the sole and finally can lead to exungulation, similar to foot rot. Treponema spp. are often found in CODD lesions analogous to digital dermatitis (Mortellaro's disease) in cattle. Involvement of Dichelobacter nodosus (D. nodosus) is considered a risk factor, but the presence of the bacterium is not mandatory. In February 2022, ulcerative lesions in the dorso-axial coronary band area were noticed on both claws of the left forelimb in an ewe. Histology of the biopsy showed hyperkeratosis and erosion with exocytosis and crust formation. Treponema spp. PCR and fluorescence in situ hybridization (FISH) were positive for Treponema phylotype 1 (PT1). In addition, D. nodosus and Porphyromonas levii could be detected in the biopsy using PCR. A single local application of chlortetracycline spray led to clinical healing within two weeks, no recurrence was seen within the following two months. Three control sheep, which were kept together with the diseased sheep, did not show any clinical signs of CODD. Treponema spp could not be found in interdigital and coronary band biopsies by PCR or FISH. This is the first description of CODD in Switzerland and aims to sensitize veterinarians to CODD as a differential diagnosis for foot diseases in sheep.

INTRODUCTION: La dermatite digitale contagieuse ovine (contagious ovine digital dermatitis; CODD) est une maladie infectieuse des onglons des moutons d'importance croissante. À ce jour, la CODD a été décrite en Grande-Bretagne, Irlande, Suède et Allemagne, et maintenant pour la première fois également en Suisse. Au contraire du piétain, les lésions de CODD ne s'étendent pas à partir de l'espace interdigité, mais elles commencent en général au bord coronaire dorsal/abaxial. De là, les lésions peuvent s'étendre à la corne de la paroi et à la sole, ce qui peut finalement conduire à une perte complète de la boite cornée de l'onglon, comme en cas de piétain. En analogie à la dermatite digitale (maladie de Mortellaro) chez les bovins, des tréponèmes sont souvent mis en évidence dans les lésions de CODD. La présence de Dichelobacter nodosus (D. nodosus) est considérée comme un facteur de risque, mais elle n'est pas indispensable au développement de la CODD. Des lésions ulcératives dans la région du bord coronaire dorso-axial des deux onglons antérieurs d'une brebis ont été remarqués en février 2022. L'examen histologique de la biopsie de la lésion de CODD a montré une hyperkératose ainsi que des érosions avec de l'exocytose et la formation de croûtes. Aussi bien la PCR pour les Treponema spp. que l'hybridisation in-situ à fluorescence (FISH) étaient positives pour Treponema Phylotype 1 (PT1). De plus, D. nodosus et Porphyromonas levii ont été mis en évidence dans la biopsie. Une application locale unique de spray à la tétracycline après le prélèvement de la biopsie a conduit à une guérison clinique en deux semaines, et aucune récidive n'a été observée dans le deux mois suivants. Trois moutons de boucherie qui étaient détenus avec la brebis malade mais ne présentaient pas de lésions de CODD ont servi de contrôles négatifs. Des Treponema spp. n'ont été mis en évidence chez ces animaux, ni dans des biopsies du bord coronaire ni dans celles de l'espace interdigité. Cette étude représente la première description de la CODD en Suisse et est destinée à sensibiliser la profession vétérinaire à la CODD comme diagnostic différentel en cas de maladies des onglons chez les moutons.

Eficácia in sílico do florfenicol no tratamento de pododermatite infecciosa por Fusobacterium necrophorum em ovelhas / In sílico efficacy of florfenicol in the treatment of Fusobacterium necrophorum infectious pododermatitis in sheep

Objetivou-se comparar o efeito in silico do florfenicol nas doses de 20 e 30 mg/Kg em ovinos pelas vias intravenosa (IV) e intramuscular (IM), usando a modelagem PK/PD. Realizou-se uma simulação de Monte Carlo com base nos dados de concentração plasmática de um estudo publicado anteriormente. Calculou-se a área sob a curva (ASC) e as taxas de eficácia do florfenicol para os efeitos bacteriostático, bactericida e de erradicação bacteriológica. A dose de 20 mg/Kg IV demonstrou efeitos de erradicação de 100, 93 e 0% para CIM de 0,5, 1 e acima, respectivamente. O efeito bacteriostático foi de 99 e 90% para CIM de 4 e 2 µg/ml, enquanto o bactericida foi de 14% para CIM de 2 µg/ml. A dose de 30 mg/Kg IV apresentou 100% de erradicação para CIM de 1 µg/mL e 100% de efeito bactericida para CIM de 2 µg/mL. Há 100% de efeito bacteriostático em CIM de 4 µg/ml. As doses de 20 e 30 mg/Kg IM mostraram 100% de erradicação para CIM até 1 µg/mL e 0% para CIM maiores. O efeito bacteriostático foi mantido em 100% para uma CIM de 4 µg/mL em ambas as doses. Este estudo mostra o efeito de erradicação bacteriológica do florfenicol nas doses de 20 e 30 mg/Kg, IV e IM. Recomenda-se que seja feito um estudo de eficácia in vivo com a dose de 30mg/Kg IM em ovinos infectados por F. necrophorum com MIC superior a 2 µg/mL.

We aimed to compare the in silico effect of florfenicol at doses of 20 and 30 mg/Kg in sheep by intravenous (IV) and intramuscular (IM) routes, using PK/PD modeling. We performed a Monte Carlo simulation based on plasma concentration data from a previously published study. We calculated the area under the curve (AUC) and the efficacy rates of florfenicol to bacteriostatic, bactericidal, and bacteriological eradication effects. The dose of 20 mg/Kg IV demonstrated 100, 93, and 0% eradication effects for MICs of 0.5, 1, and above, respectively. The bacteriostatic effect was 99 and 90% for MIC of 4 and 2 µg/ml, while the bactericide was 14% for MIC of 2 µg/ml. The 30 mg/Kg IV dose showed 100% eradication for MIC of 1 µg/mL and 100% bactericidal effect for MIC of 2 µg/mL. There is a 100% of bacteriostatic effect at MIC of 4 µg/ml. Doses of 20 and 30 mg/Kg IM showed 100% eradication for MIC up to 1 µg/mL and 0% for MIC above. The bacteriostatic effect was maintained at 100% for a MIC of 4 µg/mL at both doses. This study shows the bacteriological eradication effect of florfenicol at doses of 20 and 30 mg/Kg, IV, and IM. Therefore, we recommend an in vivo efficacy study with a dose of 30mg/Kg IM in sheep infected with F. necrophorum with MIC greater than two µg/mL.

Whole-flock, metaphylactic tilmicosin failed to eliminate contagious ovine digital dermatitis and footrot in sheep: a cluster randomised trial.

The aim of this study was to evaluate the clinical success of whole-flock systemic tilmicosin and enhanced biosecurity in eliminating active contagious ovine digital dermatitis (CODD) from sheep flocks. Thirty flocks in the UK were randomly allocated to receive either treatment as usual (as per the farmer's normal routine) or whole-flock treatment with tilmicosin, together with isolation and extended treatment of clinically affected individuals and isolation and treatment of purchased sheep during the study period. All flocks were visited once at onset of the trial to examine all sheep. One year later, all sheep were re-examined to determine the presence/absence of clinical lesions. The primary outcome was the clinical elimination of CODD from flocks. Secondary outcomes were reduction in prevalence of CODD, clinical elimination of footrot and reduction in prevalence of footrot. The analysis included 11 control flocks and 13 intervention flocks, with initially 3460 and 4686 sheep, respectively. For CODD: at follow-up, in the intervention group, 6/13 (46 per cent) flocks had a prevalence of zero compared with 1/11 (9 per cent) in the control group (P=0.12). For footrot: at follow-up, no flocks had a prevalence of zero. Therefore, the intervention is not recommended for the elimination of CODD or footrot in the UK.

Clinical evidence for individual animal therapy for papillomatous digital dermatitis (hairy heel wart) and infectious bovine pododermatitis (foot rot).

Data supporting individual animal therapy for papillomatous digital dermatitis (PDD) and infectious pododermatitis (IP) in cattle are available for treatment with multiple drugs in the form of randomized, prospective clinical trials conducted in naturally occurring disease with negative controls and masked subjective evaluators. In the case of PDD, these trials support the use of topical tetracycline and oxytetracycline, lincomycin, a copper-containing preparation, and a nonantimicrobial cream. In individual therapy for IP, trial evidence is available to support systemic treatment with ceftiofur, florfenicol, tulathromycin, and oxytetracycline. However, it was not available for IP standards such as penicillin G, sulfadimethoxine, and tylosin.

Impact of footrot vaccination and antibiotic therapy on footrot and contagious ovine digital dermatitis.

Footrot and contagious ovine digital dermatitis (CODD) are common causes of foot disease of sheep in the UK. The study reported here is a split flock randomised treatment trial undertaken on a group of 748 fattening lambs on a UK sheep farm affected by CODD and footrot. The sheep were randomly assigned to one of two treatment protocols. In protocol A, all sheep were given two doses of footrot vaccine (Footvax, MSD), plus targeted antibiotic therapy (long-acting amoxicillin, Betamox LA, Norbrook Pharmaceuticals) to sheep with foot lesions likely to be associated with a bacterial infection. In protocol B, the sheep only received targeted antibiotic therapy. Sheep were re-examined and foot lesions recorded five and nine weeks later. New infection rates in the footrot vaccinated group were lower compared with the vaccinated group for both CODD (18.2 per cent compared with 26.4 per cent, P=0.014) and footrot (12.55 per cent compared with 27.5 per cent, P<0.001). Recovery rates were unaffected for CODD (80.46 per cent compared with 70.97 per cent, P=0.14) but higher for footrot (92.09 per cent compared with 81.54 per cent, P=0.005) in sheep which received the vaccine. On this farm, a footrot vaccine efficacy of 62 per cent was identified against footrot and 32 per cent against CODD infection. An association between a sheep having footrot at visit 1 and subsequently acquiring CODD was identified (odds ratio [OR] 3.83, 95 per cent CI 2.61 to 5.62, P<0.001). These results suggest a role for infection with Dichelobacter nodosus in the aetiopathogenesis of CODD on this farm.

Comparison of ceftiofur sodium and oxytetracycline for treatment of acute interdigital phlegmon (foot rot) in feedlot cattle.

OBJECTIVE: To determine whether ceftiofur sodium would be useful for treatment of acute interdigital phlegmon (foot rot) in cattle. DESIGN: Randomized controlled trial. ANIMALS: 308 cross-bred yearling steers with clinical signs of acute interdigital phlegmon (i.e., lameness with interdigital swelling, interdigital lesions, or both). PROCEDURE: Steers were randomly assigned to 1 of 3 treatment groups: ceftiofur at a dosage of 0.1 mg/kg (0.045 mg/lb) of body weight, IM, every 24 hours; ceftiofur at a dosage of 1.0 mg/kg (0.45 mg/lb), IM, every 24 hours, and oxytetracycline at a dosage of 6.6 mg/kg (3 mg/lb), IM, every 24 hours. All animals were treated for 3 days; treatment was considered successful if animals were no longer lame on day 4. Biopsy specimens were collected prior to treatment from 5 animals in each group and submitted for anaerobic bacterial culture and histologic examination. RESULTS: Success rates for the high-dosage ceftiofur (94/129; 73%) and oxytetracycline (87/128; 68%) groups were significantly higher than that for the low-dosage ceftiofur group (5/50; 10%), but there were no significant differences between the high-dosage ceftiofur and oxytetracycline groups. Anaerobic bacteria most frequently isolated from biopsy specimens were Porphyromonas levii and Provetella intermedia. CLINICAL IMPLICATIONS: Use of ceftiofur at a dosage of 1.0 mg/kg for treatment of cattle with acute interdigital phlegmon was as effective as use of oxytetracycline at a dosage of 6.6 mg/kg. However, ceftiofur has a negligible withdrawal time and, therefore, may be a better choice for treatment of near-market weight animals.