Postural and gait abnormalities in a group of Romney lambs due to pain induced by severe chronic cutaneous dermatophilosis.

CASE HISTORY: Fifteen lambs from a flock of 1,000, 5-month-old Romney lambs in the Manawatu region of New Zealand, developed unusual postural and gait abnormalities during the summer of 2020. In mid-January, the lambs were grazing a raphanobrassica crop (xRaphanobrassica; Brassica oleracea x Raphanus sativus) but were removed from this crop soon after as they developed dermal lesions on the pinnae consistent with photosensitisation (colloquially known as "rape scald"). The lambs were placed onto a shaded paddock containing a pasture of predominantly perennial ryegrass (Lolium perenne) and white clover (Trifolium repens). One week following removal from the crop (late January), the 15 lambs developed abnormal postures and gaits that were described by farm staff as "neurological" and "swayback-like". CLINICAL FINDINGS: From a distance, all 15 lambs exhibited remarkably similar abnormal posture and gait whereby their weight was borne on their carpi, and they appeared to crawl while walking due to crouched hindquarters and prominent lordosis. Of the affected lambs, five were submitted for clinical examination. All five had normal vital signs. The results of neurological examinations were within normal limits. In response to palpation of the dorsum, the lambs performed an exaggerated and unusual dipping motion, particularly when pressure was applied over the lumbar spine. Parting of the fleece over the dorsum revealed thickened, indurated skin that cracked and tore easily. PATHOLOGICAL FINDINGS: The shorn pelt of a euthanised lamb revealed a large (100 cm × 40 cm), locally extensive, irregular ovoid region of the skin of the dorsum that was markedly thickened, indurated and crusted. Impression smears of the lesions revealed long filamentous chains of plump coccoid bacteria separated by transverse and longitudinal septa, consistent with Dermatophilus congolensis. Histopathology of the lesions revealed severe, chronic-active, locally extensive, necrosuppurative dermatitis with marked acanthosis, orthokeratotic and parakeratotic hyperkeratosis, ulceration, filamentous bacteria and coccoid zoospores. DIAGNOSIS: Cutaneous dermatophilosis due to Dermatophilus congolensis. CLINICAL RELEVANCE: Painful dermal lesions due to severe dermatophilosis of the dorsal skin of sheep are capable of causing postural and gait abnormalities that may be misinterpreted as signs of neurological abnormality. Such dermal lesions may be concealed by an apparently normal fleece.

Identification and Antimicrobial Resistance of Dermatophilus congolensis from Cattle in Saint Kitts and Nevis.

Dermatophilosis is a form of dermatitis caused by the bacterium Dermatophilus congolensis. The disease usually presents as localized purulent dermatitis, crusty hair masses or widespread matting of the hair. This condition is most common in domestic ruminants; but it can also affect other wild animals and humans. Antimicrobial therapy is used in many regions to treat clinical dermatophilosis with varying results. In this study, we aimed to assess the antimicrobial susceptibility of D. congolensis isolates. Fifty-two isolates were obtained from animals showing clinical signs of the disease at farms in St. Kitts. The isolates were then confirmed as D. congolensis by phenotypic tests, PCR and MALDI-TOF Mass Spectrometry. Furthermore, minimum inhibitory concentrations (MIC) of 16 antimicrobial agents were determined, using the broth microdilution method. Although most antimicrobials showed MICs in line with published values, the tetracycline results displayed a clear bimodal distribution over the tested range, with most isolates showing low MICs and 6 isolates much higher values (+/- 100-fold increase). These results indicate the presence of acquired tetracycline resistance in D. congolensis on the island of St. Kitts. Whether the current observation has implications for efficacy of treating the disease must be confirmed in further research.

The Patterns and Causes of Dermatitis in Terrestrial and Semi-Aquatic Mammalian Wildlife.

Causative disease and stress agents which manifest as dermatitis in mammals have varying effects on individual animals, from benign irritation and inflammation, to causing morbidity and even mortality. Bacteria, viruses and ectoparasites are all potential causes of dermatitis, and it can be exacerbated by various environmental, genetic and social factors. Furthermore, it is uncertain whether dermatitis is more likely to manifest in already-vulnerable wildlife species. Here, we systematically review the literature for reports of dermatitis in terrestrial and semi-aquatic wild mammalian species, with the goal of determining the biogeographical scale of dermatitis reports, the causes of dermatitis, and whether manifestation of dermatitis is reported more commonly in certain wildlife species or their captivity status (i.e., free-living, in captivity or in a laboratory). We reveal biases in the reporting of dermatitis by a biogeographic realm, with 55% of cases reported in the Nearctic, and towards particular orders of mammals, namely Artiodactyla and Carnivora. Overall, free-living wildlife is almost twice as likely to be reported as having dermatitis than individuals in captivity and six times more likely than individuals in laboratories, which we interpret as owing to exposure to a broader spectrum of parasites in free-ranging individuals, and potential reporting bias in captive individuals. Notably, dermatitis was reported in 23 threatened species, with some species more likely than others to be reported exhibiting clinical signs of dermatitis resulting from underlying health problems. We also find that threatened species are more likely to be reported as having dermatitis in captivity, particularly outside of their endemic home range. This review highlights diverse patterns of dermatological disease causes in captive and free-ranging wildlife, conditions under which they are more likely to be documented, and the need for cross-disciplinary research to ascertain (and so better manage) the varied causes.

Incidence and biochemical parameters of dermatophilosis in Nigerian cattle breeds from livestock markets, Oyo state, Nigeria.

Dermatophilosis is one of the major economically important diseases of cattle in Nigeria. Managing the condition has been very challenging and re-occurrence has been reported with moderate to high morbidity and mortality. The incidence and biochemical features of cattle with dermatophilosis was conducted in June to December 2016 across the four geopolitical zones of Oyo state, Nigeria. Clinical diagnosis were made based on appearance of dermatophilosis lesion, breeds morphologically characterized, ageing were based on rostral dentition and severity based on the extent and nature of the lesion. Biochemical analysis was based on standard procedure as prescribed by Fortress International. Fifty cattle were found to be infected with clinical dermatophilosis during the period of the study. Twenty four (48%) in Ibadan zone, 14 (28%) in Oyo/Ogbomosho, 8 (16%) in Oke-ogun and 4 (8%) in Ibarapa zone. Breeds distribution across the zones showed 28 (56%) White Fulani, 5 (10%) Sokoto Gudali, 3 (6%) Adamawa Gudali, 7 (14%) Red Bororo, 5 (10%) Cross breeds while the Kuri was 2 (4%). Regarding animal ages, less than 2 years old were 2 animals (4%) while the adults were 48 animals (96%) and they fall under the categories of 2-2½ years of age, 3-3½ years of age and those which are over 3½ years of age. The different levels of severity were categorized into mild (20 (40%)), moderate (23 (46%)) and severe (7 (14%)) .The best parameters were seen in White Fulani, while the least were seen in Adamawa Gudali. The age group in the category of 3 - 3½ years had most of the best serum values while the least values were seen in animals less than 2 years of age. Cattle exhibiting mild lesions had most of the best serum values and the least values were observed in cattle with severe lesions. No significant difference (p > 0.05) was observed in the mean values for the various parameters studied among the breeds, age, and severity of condition.

Pastoralists' knowledge and practices towards clinical bovine dermatophilosis in cattle herds of North-Central Nigeria: the associated factors, burden and economic impact.

Dermatophilosis is a contagious disease of high economic importance. The study assessed knowledge/awareness and clinical burden of and mitigation measures practised against clinical bovine dermatophilosis in pastoral herds of North-Central Nigeria and associated socio-cultural factors that predisposed to its occurrence in herds. A cross-sectional survey was conducted between October 2015 and September 2016. Questionnaires were administered on pastoralists and clinical assessment of cattle with gross pathological lesions indicative of dermatophilosis conducted. Associated economic impact was estimated. All 384 selected pastoralists participated in the survey. The majorities of nomadic (97.4%) and sedentary (68.2%) pastoralists significantly (p < 0.05) reported to have heard about dermatophilosis. Majorities of the sedentary (91.7%) and nomadic (97.4%) pastoralists mentioned the use antibiotics to manage the disease. Pastoralists in age group 70-79 years were more likely (OR 15.22; 95% CI 4.69, 49.34) to possess satisfactory knowledge about the disease. Culture of giving out cattle as gift or payment for dowry was more likely (OR 28.56; 95% CI 15.64, 52.12) to influence dermatophilosis occurrence in herds. Overall clinical dermatophilosis burden was 3.6% (95% CI 3.46, 3.80) and the annual economic impact was estimated at 908,463.9 USD. This study has given an idea to the status of pastoralists' levels of awareness about dermatophilosis in Nigeria, which can be harnessed by policy makers to develop its mitigation measures. Significant influence of pastoralists' socio-cultural activities on dermatophilosis occurrence in herds was identified. Surveillance and control programmes towards dermatophilosis that take these factors into consideration will be beneficial to the herders.

Successful therapy in unusual generalized Dermatophilus congolensis infection in a calf based on modified in vitro disk diffusion test / Sucesso no tratamento de infecção generalizada em bezerra por Dermatophilus congolensis baseado em teste in vitro modificado de difusão com discos

Bovine dermatophilosis is a dermatitis characterized by typical focal or localized lesions with "paintbrush" aspect and occasionally as disseminated cutaneous disease. We report the case of a one-year-old Nelore female with history of chronic cutaneous disseminated lesions that appeared immediately after a rainfall period. Serous to purulent exudates, hair with tufted appearance, hyperkeratotic, non-pruritic, hardened, yellowish to brown, and coalescent crusty lesions were observed distributed all over its body. Removal of the crusts revealed ulcerated or hemorrhagic areas, with irregular elevated crusts like "paintbrush". Microbiological diagnosis enabled the identification of a microorganism, the Dermatophilus congolensis. Despite disseminated and chronic lesions, we obtained a successful therapy with parenteral therapy using long-acting tetracycline based on modified in vitro disk diffusion test. The present report highlights success therapy in uncommon generalized bovine dermatophilosis with selection of first-choice drugs based on modified in vitro susceptibility test, and need of responsible use of antimicrobials in livestock.(AU)

A dermatofilose bovina é uma dermatite caracterizada por lesões focais ou localizadas com aspecto de "pincel" e, ocasionalmente, como lesão cutânea disseminada. Relata-se o caso de uma fêmea bovina de um ano de idade, que foi atendida apresentando história de lesões cutâneas crônicas imediatamente após um período de alta pluviosidade. Ao exame clínico, lesões serosas a purulentas, com hiperqueratose, coalescentes, não pruriginosas, ressecadas, de coloração amarelada à acinzentada foram observadas distribuídas de modo generalizado pelo animal. A remoção das crostas revelou áreas ulceradas ou hemorrágicas, com crostas irregulares e elevadas semelhantes a "pincel". O diagnóstico microbiológico possibilitou a identificação do micro-organismo Dermatophilus congolensis. Apesar das lesões disseminadas e crônicas, a cura do animal foi obtida com tratamento parenteral usando oxitetraciclina de longa duração, baseado em teste in vitro de sensibilidade microbiana modificado. O presente relato ressalta o sucesso no tratamento de caso incomum de lesões generalizadas de dermatofilose bovina com respaldo de teste in vitro de sensibilidade modificado, bem como a necessidade do uso responsável de antimicrobianos em animais de produção.(AU)

Prevalence of bovine dermatophilosis and disease-associated alleles in zebu Goudali cattle and their Italian Simmental crosses ranching in the western highland plateau savannah of Cameroon.

Abundance of native pastures makes Cameroon's western highland savannah (WHS) a hotspot for low-input beef-type cattle. Dumbo Ranch is central to cattle seed stock multiplication in WHS and holds that Dermatophilus congolensis infection undermines production. The bovine BoLA-DRB3 has been variously demonstrated as the principal gene of the major histocompatibility locus associated with immunity and resistance to dermatophilosis in cattle. We studied the profile of dermatophilosis prevalence in zebu Goudali (G) and its Simmental composite, SimGoud (SG), at Dumbo Ranch and determined the distribution of a dermatophilosis-associated susceptibility allele of the BoLA-DRB3 gene by allele-specific polymerase chain reaction (PCR). We recorded a 42 % prevalence of dermatophilosis in the studied cohort (337 animals). Dermatophilosis was more common in older cattle than in cattle ≤36 months (p ≤ 0.05). G was more affected compared to SG, because of the prevalence of the disease in the oldest animals and the age distribution of the experimental subjects. No susceptible homozygote was observed. About 85 and 15 % of the cohort carried the homozygous resistant and heterozygous condition, respectively. This genotype distribution was not affected by cattle type. The study confirms the presence of dermatophilosis among G and SG cattle in WHS. However, there was no correlation between the presence of the disease-associated susceptible allele considered and clinical manifestation. Screening for this dermatophilosis resistance-associated allele of BoLA-DRB3 gene appeared not useful for selection of G and SG in WHS.

Development of a real-time SYBR Green PCR assay for the rapid detection of Dermatophilus congolensis.

Methods such as real time (RT)-PCR have not been developed for the rapid detection and diagnosis of Dermatophilus (D.) congolensis infection. In the present study, a D. congolensis-specific SYBR Green RT-PCR assay was evaluated. The detection limit of the RT-PCR assay was 1 pg of DNA per PCR reaction. No cross-reaction with nucleic acids extracted from Pseudomonas aeruginosa, Mycobacterium tuberculosis, Staphylococcus aureus, or Austwickia chelonae was observed. Finally, the RT-PCR assay was used to evaluate clinical samples collected from naturally infected animals with D. congolensis. The results showed that this assay is a fast and reliable method for diagnosing dermatophilosis.

Development of a real-time SYBR Green PCR assay for the rapid detection of Dermatophilus congolensis

Methods such as real time (RT)-PCR have not been developed for the rapid detection and diagnosis of Dermatophilus (D.) congolensis infection. In the present study, a D. congolensis-specific SYBR Green RT-PCR assay was evaluated. The detection limit of the RT-PCR assay was 1 pg of DNA per PCR reaction. No cross-reaction with nucleic acids extracted from Pseudomonas aeruginosa, Mycobacterium tuberculosis, Staphylococcus aureus, or Austwickia chelonae was observed. Finally, the RT-PCR assay was used to evaluate clinical samples collected from naturally infected animals with D. congolensis. The results showed that this assay is a fast and reliable method for diagnosing dermatophilosis.

Alopecia in the horse - an overview.

Dr Stannard explains different forms of alopecia in the horse with emphasis on the hair follicle and its function in the production of hairs. Both normal and abnormal patterns of hair growth and shedding in the horse are reviewed. Overviews of several specific hair follicle abnormalities, both inflammatory and noninflammatory, are discussed in detail with their clinical relevance. Some of the clinical entities covered in this section (linear alopecia and alopecia areata) are caused by immunological attack against normal structures and could have been placed in Immunologic diseases. However, because the clinical presentation for these entities is alopecia, Dr Stannard chose to include them in his notes on alopecia. Other inclusions in this section include cutaneous bacterial infections (e.g. pastern folliculitis and dermatophilosis) as well as fungal infections of the hair (dermatophytosis).

Efficacy of Long Acting Oxytetracycline in the Treatment and Control of Bovine Dermatophilosis.

Abstract- Fifty-two cattle on two ranches in St. Kitts were divided into initial treatment and control groups, matched as closely as possible by age, sex and extent of dermatophilosis. Nine unaffected animals were included. The initial treatment group was given long-acting oxytetracycline at the rate of 20 mg.kg-1 . After 4 weeks the control group was similarly treated. The cattle were observed at weekly intervals for a total of 6 weeks. In each group there was a pronounced decrease in the extent of the disease after treatment. This was most apparent in lightly affected animals and on the trunk. Lesions tended to persist in the tick predilection sites and extremities. Complete recovery occurred in 8 (21 per cent) of cattle. The disease tended to recur in treated animals particularly on one of the ranches in which a low standard of husbandry prevailed. On the other ranch improvements in tick control and feeding were associated with a continuing low level of infection. The results show that long-acting oxytetracycline can be used to conveniently halt outbreaks of dermatophilosis and allow time for changes in management designed to reduce recurrence of the disease. Résumé- 52 bovins présents sur 2 ranchs à Saint-Kitts, ont été divisés en groupes d'animaux traités et en groupe d'animaux témoins, répartis aussi minutieusement que possible selon l'âge, le sexe et l'extension de la dermatophilose. Le groupe des animaux traités a reçu de l'oxytétracycline-retard à la dose de 20 mg.kg-1 . Après 4 semaines, le groupe d'animaux témoins fut traité de la même manière. Les bovins furent observés une fois par semaine pendant une durée totale de 6 semaines. Dans chaque groupe, il y eut une baisse sensible de l'extension de la maladie après le traitement. Ce fut le plus manifeste sur des animaux légèrement atteints et sur le tronc. Les lésions ont tendu à persister sur les sites de prédilection des tiques et sur les extrémités. Une guérison complète fut notée sur 8 (21%) des bovins. Les maladies tendaient à récidiver sur les animaux traités, principalement dans l'un des ranchs, où les conditions d'entretien étaient d'un niveau médiocre. Dans l'autre ranch, des améliorations dans l'erradication des tiques et dans l'alimentation ont été associées avec la persistance d'un niveau faible d'infection. Les résultats montrent que l'oxytétracycline retard peut être utilisée pour árrêter commodément les poussées de dermatophilose et laisser du temps pour modifier les méthods afin de récluire la récidive de la maladie. Zusammenfassung- 52 Rinder in zwei Betrieben auf St. Kitts wurden in je eine Erstbehandlungs-und eine Kontrollgruppe aufgeteilt, die mÖglichst ähnlich in Alter, Geschlecht und Ausprägungsgrad der Dermatophilose waren. Neun dieser Tiere waren nicht erkrankt. Die Erstbehandlungsgruppe erhielt ein Langzeit-Oxytetracyclin in der Dosierung von 20mg.kg-1 . Nach 4 Wochen wurde die Kontrollgruppe nach dem gleichen Schema behandelt. Die Tiere wurden über einen Zeitraum von sechs Wochen in wÖchentlichen Abständen untersucht. In beiden Gruppen besserte sich der Schweregrad der Erkrankung nach Therapie deutlich, besonders bei den nur leicht befallenen Tieren und bei Läsionen im Stammbereich. Dagegen neigten die Veränderungen an den Prädilektionsstellen für Zecken und an den Gliedmaßen zur Persistenz. Acht der Tiere (21%) wurden vÖllig wiederhergestellt. Die Erkrankung neigte aber bei den therapierten Tieren zu Rezidiven, vor allem in einem der Betriebe mit niedrigem Pflegeniveau. Nach den vorliegenden Untersuchungen ist die Verwendung von Langzeit-Oxytetracyclin ein brauchbares Mittel, um die Dermatophilose zum Stillstand zu bringen und neue Ausbrüche zu verhindern, bis weitere Änderungen im Management zur Verringerung der Rezidivrate getroffen worden sind. Resumen Cincuenta y dos vacas de 2 explotaciones en St. Kitts se dividieron en un grupo de tratamiento y un grupo de control. Ambos grupos contenian aproximadamente la misma distributión de sexos y la dermatofilosis estaba extendida en igual medida. Se incluyeron 9 animales no afectados. Los animates del grupo de tratamiento inicial recibieron oxitetraciclina de actión retardada a una dosis de 20mg.kg-1 . Cuatro semanas más tarde los animales del grupo de control recibieron el mismo tratamiento. Las vacas fueron observadas semanalmente durante 6 semanas. En cada grupo se produjo una marcada reducción en la extensién de la enfermedad después del tratamiento. Esto fue más marcado en aquellos animales afectados sólo de forma leve en la región del tronco. Las lesiones tendian a persistir en las zonas de predilectión de las garrapatas y en las extremidades. En ocho animales se observó una curatión completa (21%). La enfermedad tendia a recidivar en los animales tratados expecialmente en una de las explotaciones en la cual se mantenían unas condiciones de cría bastante desfavorables. En la otra explotación el control de garrapatas y una mejoria en la alimentatión aparecieron asociadas a un bajo nivel de presentación de la enfermedad. Estos resultados indican que la oxitetraciclina de actión retardada puede utilizarse para controlar focos de dermatofilosis, produciendo remisiones que permiten mejorar el manejo de las explotaciones y evitar recidivas de la enfermedad.