Ischemic teat necrosis (ITN) is a growing problem in the dairy industry characterized by teat lesions, necrosis, pruritus and automutilation. Despite the economic and welfare consequences, there is no treatment, and the etiology of the disease remains poorly understood. The aim of this study was to investigate ITN by analyzing its clinical presentation, potential risk factors and microbial involvement. Methods included collection of milk and swab samples from affected cows over a period of one-and-a-half years and completion of questionnaires by veterinarians and farmers. Microbial testing included PCR testing for Treponema spp. and cultural testing by anaerobic and aerobic incubation on blood agar. The results showed a high and significant prevalence of Treponema spp. and Staphylococcus aureus in affected teats compared to non-ITN-affected control teats, indicating their potential role in the development of ITN. Other factors such as edema and milking practices also appear to contribute to the tissue damage. First-lactation and early-lactation heifers are particularly at risk. In conclusion, ITN appears to have a multifactorial etiology with both infectious and non-infectious factors playing a role. Further research is needed to better understand the complex interplay of these factors and to develop effective prevention and management strategies.

The objective of this study was to determine whether a novel footbath solution containing stannous fluoride (SnF2) was superior to 5% copper sulfate solution for the treatment and prevention of digital dermatitis (DD) in dairy cattle. Study 1 was conducted over 4 weeks in Missouri and involved 34 lactating Holstein-Friesian cows with hind feet DD lesions. Cows in group SF walked through a footbath containing a proprietary formulation of SnF2 once weekly, whereas cows in group CS walked through a 5% CuSO4 footbath once daily for 5 d each week. Study 2 was conducted over 8 weeks in California and involved 40 lactating Holstein-Friesian cows with hind feet DD lesions. Cows in group SF walked through a SnF2 footbath for 3 consecutive days then once a week for the following 7 weeks. Cows in group CS walked through a 5% CuSO4 footbath 3 times each week for 8 weeks. Data collection included lesion type, lesion area, locomotion score, and pain score. Digital dermatitis was actively transmitted in study 1, and lesion area and locomotion scores were lower in group SF than group CS. In contrast, DD was not actively transmitted in study 2, and lesion area and locomotion scores were similar in groups SF and CS. Stannous fluoride delayed the development of active DD lesions in study 1 compared with copper sulfate, with a lower relative risk (0.57, P < 0.001) of a hind foot developing an active DD lesion over 28 d. However, SnF2 decreased the rate that active DD lesions transitioned to M3, M4, or M0 lesions compared with 5% copper sulfate in both studies, with the relative risk of a hind foot with an active DD lesion transitioning to M3, M4, or M0 in group SF being slightly lower in study 1 (0.83, P = 0.042) and study 2 (0.90, P = 0.020) than group CS. Our findings demonstrated that walking cows through a stannous fluoride footbath once per week in a herd undergoing active transmission of infection was more effective in preventing active DD lesions, but less effective in treating active DD lesions, than walking cows through a copper sulfate footbath 4 times per week. The novel SnF2 footbath solution shows promise for controlling DD in dairy herds that want an alternative footbath solution to CuSO4 and are interested in limiting the environmental accumulation of copper.

Digital dermatitis (DD) is a skin disease in cattle characterized by painful inflammatory ulcerative lesions in the feet, mostly associated with local colonization by Treponema spp., including Treponema phagedenis. The reason why most DD lesions remain actively inflamed and progress to chronic conditions despite antibiotic treatment remains unknown. Herein, we show an abundant infiltration of proinflammatory (CD14highCD16low) monocytes/macrophages in active DD lesions, a skin response that was not mitigated by topical treatment with oxytetracycline. The associated bacterium, T. phagedenis, isolated from DD lesions in cattle, when injected subcutaneously into mice, induced abscesses with a local recruitment of Ly6G+ neutrophils and proinflammatory (Ly6ChighCCR2+) monocytes/macrophages, which appeared at infection onset (4 days post challenge) and persisted for at least 7 days post challenge. When exploring the ability of macrophages to regulate inflammation, we showed that bovine blood-derived macrophages challenged with live T. phagedenis or its structural components secreted IL-1β via a mechanism dependent on the NLRP3 inflammasome. This study shows that proinflammatory characteristics of monocytes/macrophages and neutrophils dominate active non-healing ulcerative lesions in active DD, thus likely impeding wound healing after antibiotic treatment.

Interdigital hyperplasia (IH) is a fold of fibrous tissue protruding into the interdigital space that rarely occurs in sheep. Interdigital hyperplasia secondary infected with bovine digital dermatitis (BDD) treponemes has been reported in cattle in the course of the increasing spread of classical BDD lesions. In this report, we describe proliferative/ulcerative interdigital lesions associated with contagious ovine digital dermatitis (CODD) treponemes and clinically scored as (IH+CODD), occurring in both hind limbs of a ram and the left hindlimb of a ewe. Both cases exhibited epidermal hyperplasia, parakeratosis and focal-extensive areas of epidermal necrosis with numerous infiltrating neutrophils. Treponema PCR and fluorescence in situ hybridization (FISH) were positive for Treponema phylotype 1 (PT1). In addition, Dichelobacter (D.) nodosus and Porphyromonas (P.) levii were detected in the biopsy by PCR. In three slaughter sheep, without claw lesions, which were kept together with both affected sheep, Treponema spp. were detected neither with PCR nor FISH; the PCRs for D. nodosus and P. levii were also negative. Complete clinical healing occurred in the ewe within 6 weeks after three local applications of a chlortetracycline spray in 2 weeks intervals. This report is the first description of IH+CODD in sheep as demonstrated by a combination of histopathological and molecular analyses.

Digital dermatitis (DD) associated with the presence of multiple Treponema spp. was recently described for the first time in European bison (Bison bonasus). DD is characterized by skin inflammation in the distal foot area in various ungulates. The objective of this proof of concept study was to test a treatment protocol adopted from cattle for its applicability in this wildlife species using five animals. Keratolytic salicylic acid paste was administered topically under bandages for seven days to enable removal of the affected skin. All interventions were performed under general anesthesia. To evaluate the treatment efficacy, photographs and biopsies were taken pre- and post-treatment. The biopsies were examined histologically, by PCR for the presence of different bacterial species, by Treponema-specific fluorescent in situ hybridization (FISH), and by transmission electron microscopy. Based on photographs, complete clinical healing of the 15 feet with macroscopical DD lesions was achieved. Histological examination showed mild to moderate dermatitis in 17/20 feet before, and in 12/20 feet after treatment. 17/20 feet were Treponema spp. PCR positive before, and none was positive after treatment. Dichelobacter nodosus, Fusobacterium necrophorum, and Porphyromonas levii could not be detected in any of the samples. By FISH and electron microscopy, Treponema spp. could be visualized in the stratum corneum before, but not after treatment. These results suggest that this treatment method can be applied as standard practice prior to transporting DD affected European bison to prevent the spread of this contagious disease.

BACKGROUND: 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.
BACKGROUND: Die kontagiöse ovine digitale Dermatitis (contagious ovine digital dermatitis; CODD) ist eine an Bedeutung gewinnende infektiöse Klauenerkrankung beim Schaf. Bis heute wurde CODD in Grossbritannien, Irland, Schweden und Deutschland beschrieben und nun auch erstmals in der Schweiz. Im Gegensatz zur Moderhinke, breiten sich die Läsionen bei CODD nicht vom Zwischenklauenspalt aus, sondern beginnen üblicherweise am dorsalen/abaxialen Kronsaum. Von dort können sich die Veränderungen auf das Wandhorn und die Sohle ausbreiten und schliesslich bis zum Ausschuhen führen, wie das bei Moderhinke der Fall ist. Analog der Dermatitis digitalis (Mortellaro’sche Krankheit) beim Rind werden in CODD-Läsionen häufig Treponemen nachgewiesen. Eine Beteiligung von Dichelobacter nodosus (D. nodosus) gilt als Risikofaktor, jedoch ist ein Vorliegen des Bakteriums nicht notwendig. Im Februar 2022 fielen bei einer Aue an beiden Klauen der linken Vordergliedmasse ulzerative Läsionen im dorso-axialen Kronsaumbereich auf. In der histologischen Untersuchung der Biopsie der CODD-Läsion wurden Hyperkeratose sowie Erosion mit Exozytose und Krustenbildung beschrieben. Sowohl die Treponema spp. PCR als auch die Fluoreszenz-in-Situ-Hybridisierung (FISH) fielen positiv für Treponema Phylotype 1 (PT1) aus. Daneben konnte in der Biopsie D. nodosus und Porphyromonas levii mittels PCR nachgewiesen werden. Nach Entnahme der Biopsie führte eine einmalige lokale Anwendung von Chlortetrazyklin-Spray zur klinischen Abheilung innerhalb von zwei Wochen, wobei auch innerhalb der darauf folgenden zwei Monate kein Rezidiv aufgetreten ist. Als Negativkontrolle dienten drei Schlachtschafe, welche gemeinsam mit dem erkrankten Schaf gehalten wurden, jedoch keine klinischen Anzeichen von CODD zeigten. Bei diesen wurden in Kronsaum- und Interdigitalbiopsien weder in der PCR noch in der FISH Treponema spp. nachgewiesen. Diese Studie ist die Erstbeschreibung der CODD in der Schweiz und hat zum Ziel, die Tierärzteschaft für CODD als Differentialdiagnose bei Zehenerkrankungen des Schafes zu sensibilisieren.
BACKGROUND: 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.
BACKGROUND: La dermatite digitale contagiosa ovina (CODD) è una malattia infettiva podale degli ovini che sta acquisendo sempre più importanza. Ad oggi è stata descritta in Gran Bretagna, Irlanda, Svezia e Germania, e ora per la prima volta in Svizzera. In contrasto con la Zoppina, le lesioni da CODD non si diffondono dallo spazio interdigitale, ma di solito iniziano a livello del cercine coronario dorsale/abassiale. Da qui le lesioni possono estendersi alla parte parietale e alla suola ed eventualmente risultare in un’avulsione completa della capsula cornea, come nel caso della Zoppina. Analogamente alla dermatite digitale (malattia di Mortellaro) nei bovini, i treponemi sono frequentemente rilevati nelle lesioni da CODD. Il coinvolgimento di Dichelobacter nodosus (D. nodosus) è considerato un fattore di rischio, ma la presenza del batterio non è indispensabile. Nel febbraio 2022, sono state riscontrate lesioni ulcerative nella regione coronale dorso-assiale su entrambi gli unghioni dell’arto anteriore sinistro di una pecora. L’esame istologico della biopsia delle lesioni ha mostrato la presenza di ipercheratosi ed erosioni accompagnate da esocitosi e croste. Sia la PCR sia l’ibridazione in situ a fluorescenza (FISH) per Treponema spp. sono risultate positive per Treponema phylotype 1 (PT1). Inoltre, D. nodosus e Porphyromonas levii sono stati rilevati nella biopsia mediante PCR. Dopo il prelievo della biopsia una singola applicazione locale di clortetraciclina spray ha portato alla guarigione clinica entro due settimane e non si sono verificate recidive nei due mesi successivi. Tre pecore da macello, che venivano tenute insieme alla pecora affetta da CODD ma non mostravano segni clinici, sono servite da controllo negativo. In questo caso, né la PCR né il FISH per Treponema spp. sono stati messi in evidenza nelle biopsie prelevate a livello del cercine coronario e dello spazio interdigitale. Questo studio rappresenta la prima descrizione della CODD in Svizzera e ha lo scopo di educare la comunità veterinaria sulla CODD come diagnosi differenziale per le malattie podali degli ovini.

Although the link between microbial infections and Alzheimer\'s disease (AD) has been demonstrated in multiple studies, the involvement of pathogens in the development of AD remains unclear. Here, we investigated the frequency of the 10 most commonly cited viral (HSV-1, EBV, HHV-6, HHV-7, and CMV) and bacterial (Chlamydia pneumoniae, Helicobacter pylori, Borrelia burgdorferi, Porphyromonas gingivalis, and Treponema spp.) pathogens in serum, cerebrospinal fluid (CSF) and brain tissues of AD patients. We have used an in-house multiplex PCR kit for simultaneous detection of five bacterial and five viral pathogens in serum and CSF samples from 50 AD patients and 53 healthy controls (CTRL). We observed a significantly higher frequency rate of AD patients who tested positive for Treponema spp. compared to controls (AD: 62.2 %; CTRL: 30.3 %; p-value = 0.007). Furthermore, we confirmed a significantly higher occurrence of cases with two or more simultaneous infections in AD patients compared to controls (AD: 24 %; CTRL 7.5 %; p-value = 0.029). The studied pathogens were detected with comparable frequency in serum and CSF. In contrast, Borrelia burgdorferi, human herpesvirus 7, and human cytomegalovirus were not detected in any of the studied samples. This study provides further evidence of the association between microbial infections and AD and shows that paralleled analysis of multiple sample specimens provides complementary information and is advisable for future studies.

Digital dermatitis (DD) is a highly contagious and infectious disease in cattle which has a considerable negative economic impact worldwide, and adversely affects animal welfare. Members of the genus Treponema are the only bacterial agents for which there is consistent evidence of participation in DD lesions. In Chile, DD has been described since the 1990s, but only under a clinical approach. To date, the presence of the pathogenic agent has not been confirmed in Chile by any type of confirmatory microbiological diagnosis. The aim of the present study was to detect the presence of Treponema spp. DNA in lesions consistent with DD, in Chilean dairy cattle for the first time. We provide PCR confirmation of Treponema spp. in Chilean dairy cattle affected by DD. The high rate of positive results, as well as the proportion of the main Treponema species involved, is in line with what have been described in published studies elsewhere. Future herd control plans should benefit from the molecular detection of these pathogenic bacteria associated with DD.

BACKGROUND: Since the spread of classical digital dermatitis (DD) lesions within the cattle population, frequency of infections of interdigital hyperplasia (IH) lesions with DD-associated Treponema spp. (IH+DD) increased. The aim of the present case series is to describe an alternative treatment technique to surgical lesion removal or local treatment of HI+DD lesions with antibiotics. In this report, the effect of repeated local administration of salicylic acid paste, protected by a water repellent bandage was described and assessed for the treatment of four dairy cows with IH+DD lesions. Milker\'s fat Eutra was applied to the unaffected skin adjacent to the lesion to protect healthy skin from the keratolytic properties of salicylic acid paste. Treatment was repeated at weekly intervals in all four cases until the IH+DD lesions had completely clinically healed. Two cows additionally showed classical DD lesions between the heels. Clinical healing was defined as remission of IH and complete healing of the DD lesions located on IH lesions and between the heels. Complete healing was evident at three weeks of treatment in all four cases. Weekly repeated topical application of salicylic acid paste under bandage may be recommended as an alternative to surgical or antibiotic treatment of IH+DD lesions.
BACKGROUND: Seit der Ausbreitung der klassischen Dermatitis digitalis (DD)-Läsionen in der Rindviehpopulation kommen Infektionen von Hyperplasia interdigitalis (HI)-Läsionen mit DD-assoziierten Treponema spp. (HI+DD) vermehrt vor. Ziel der vorliegenden Fallserie ist es, eine alternative Behandlungstechnik zur chirurgischen Entfernung respektive lokalen Behandlung von HI+DD Läsionen mit Antibiotika zu beschreiben. In diesem Bericht wurde die Wirkung einer wiederholten lokalen Applikation von Salicylsäurepaste, welche durch einen Verband geschützt war, zur Behandlung von vier Milchkühen mit HI+DD Läsionen beschrieben und beurteilt. Zusätzlich wurde Melkfett Eutra auf die angrenzenden gesunden Hautbereiche appliziert, um die gesunde Haut vor den keratolytischen Eigenschaften der Salicylsäurepaste zu schützen. Die Behandlung wurde bei allen vier Fällen in wöchentlichen Abständen bis zur vollständigen klinischen Heilung der HI+DD Läsionen wiederholt. Zwei Kühe zeigten zusätzlich klassische DD Läsionen im Zwischenballenbereich. Klinische Heilung wurde als Rückbildung der HI und vollständige Heilung der aufsitzenden und sich im Zwischenballenbereich befindenden DD Läsionen definiert. Die Dauer bis zur vollständigen klinischen Heilung betrug in allen vier Fällen drei Wochen. Die wiederholte topische Anwendung von Salicylsäurepaste unter Verband kann als Alternative zur chirurgischen oder antibiotischen Behandlung von HI+DD Läsionen empfohlen werden.
BACKGROUND: Depuis la propagation des lésions classiques de dermatite digitale (DD) dans la population bovine, on constate une multiplication des hyperplasies interdigitées infectées par des Treponema spp. associés à la DD (IH+DD). Le but de cette étude de cas est de décrire une méthode alternative de traitement des lésions IH+DD en remplacement de l\'excision chirurgicale resp. du traitement local avec des antibiotiques. L\'effet d\'une application locale répétée sous pansement d\'une pâte à base d\'acide salicylique pour le traitement de quatre vaches présentant des lésions IH+DD est décrit et évalué dans ce rapport. De la graisse à traire a été appliquée sur la peau saine adjacente, afin de la protéger des effets kératolytiques de la pâte à base d\'acide salicylique. Le traitement a été répété à intervalles d\'une semaine jusqu\'à guérison clinique complète des lésions IH+DD pour les quatre cas. Deux vaches présentaient en plus des lésions classiques de DD dans la région des talons. La guérison clinique a été définie comme l\'involution de l\'hyperplasie interdigitée et la guérison complète des lésions de DD situées en surface et entre les talons. La durée jusqu\'à la guérison clinique complète était dans les quatre cas de trois semaines. Une application topique répétée de pâte à bas d\'acide salicylique sous pansement peut être recommandée comme alternative au traitement chirurgical et antibiotique de lésions IH+DD.
BACKGROUND: Con la diffusione delle lesioni classiche da dermatite digitale (DD) nella popolazione bovina, è aumentata la frequenza delle lesioni da iperplasia interdigitale (II) infettate con Treponema spp. associati alla DD (II+DD). Lo scopo della seguente serie di casi è di descrivere una tecnica di trattamento alternativa alla rimozione chirurgica o alla terapia antibiotica locale delle lesioni II+DD. In questa relazione, è stato valutato e descritto l\'effetto di applicazioni locali ripetute di pasta di acido salicilico protette da una benda idrorepellente, per il trattamento di quattro vacche da latte con lesioni II+DD. Il grasso da mungitura è stato applicato sulla pelle sana adiacente alla lesione per proteggerla dalle proprietà cheratolitiche dell’acido salicilico. Il trattamento è stato ripetuto ad intervalli settimanali in tutti e quattro i casi fino alla guarigione clinica completa delle lesioni II+DD. Due mucche presentavano inoltre classiche lesioni DD tra i talloni. La guarigione clinica è stata definita come la remissione della II e la completa guarigione delle lesioni DD localizzate sulle lesioni II e tra i talloni. La guarigione completa era evidente in tutti e quattro i casi dopo tre settimane di trattamento. L\'applicazione topica della pasta di acido salicilico sotto bendaggio, ripetuta settimanalmente, può essere raccomandata come alternativa al trattamento chirurgico e antibiotico delle lesioni II+DD.

Digital dermatitis (DD) lesions in cattle are characterized by the presence of multiple Treponema species. Current culture media for isolating treponemes generally uses serum supplementation from different animals to target particular Treponema sp.; however, their suitability for DD Treponema isolation has not been fully determined. We studied the effect of culture media (OTEB, NOS and TYGV) and serum supplementation on mixed Treponema spp. dynamics. Bacterial growth was evaluated by direct microscopic count, optical density, wet weight and a species-specific qPCR and the correlations between these independent methods were calculated. Wet weight, optical density and bacterial count correlated best with each other. Different Treponema species performed differently under the tested culture media. T. phagedenis growth was enhanced in OTEB media supplemented with bovine fetal serum (BFS) or horse serum (HS). T. medium had lower generation time when culture media were supplemented with rabbit serum (RS). Lowest generation time for T. pedis and T. denticola were obtained in NOS media supplemented with HS and OTEB media supplemented with BFS, respectively. Detection of cystic forms observed after 5 days of culture did not differ among the culture media. Correlation between different Treponema spp. growth quantification techniques indicated that alternative quantification methods such as qPCR and wet weight could be used depending on the purpose. We conclude that effects of culture media and serum supplementation on mixed Treponema spp. communities should be taken into account when isolating a specific Treponema species.