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.

Comprehensive Molecular Dissection of Dermatophilus congolensis Genome and First Observation of tet(Z) Tetracycline Resistance.

Dermatophilus congolensis is a bacterial pathogen mostly of ruminant livestock in the tropics/subtropics and certain temperate climate areas. It causes dermatophilosis, a skin disease that threatens food security by lowering animal productivity and compromising animal health and welfare. Since it is a prevalent infection in ruminants, dermatophilosis warrants more research. There is limited understanding of its pathogenicity, and as such, there is no registered vaccine against D. congolensis. To better understanding the genomics of D. congolensis, the primary aim of this work was to investigate this bacterium using whole-genome sequencing and bioinformatic analysis. D. congolensis is a high GC member of the Actinobacteria and encodes approximately 2527 genes. It has an open pan-genome, contains many potential virulence factors, secondary metabolites and encodes at least 23 housekeeping genes associated with antimicrobial susceptibility mechanisms and some isolates have an acquired antimicrobial resistance gene. Our isolates contain a single CRISPR array Cas type IE with classical 8 Cas genes. Although the isolates originate from the same geographical location there is some genomic diversity among them. In conclusion, we present the first detailed genomic study on D. congolensis, including the first observation of tet(Z), a tetracycline resistance-conferring gene.

Demodectic mange, dermatophilosis, and other parasitic and bacterial dermatologic diseases in free-ranging white-tailed deer (Odocoileus virginianus) in the United States from 1975 to 2012.

The white-tailed deer (Odocoileus virginianus) is a common and widespread North American game species. To evaluate the incidence, clinical manifestations, demography, and pathology of bacterial and parasitic dermatologic diseases in white-tailed deer in the southeastern United States, we retrospectively evaluated white-tailed deer cases submitted to the Southeastern Cooperative Wildlife Disease Study from 1975 to 2012. Among 2569 deer examined, bacterial or parasitic dermatologic disease was diagnosed in 88 (3.4%) individuals, with Demodex spp (n = 37; 42.0%) and Dermatophilus congolensis (n = 19; 21.6%) as the most common causes. Demodicosis was significantly more common in deer older than 2 years and was most often detected in the fall; no statistically significant sex predilection was identified. Affected animals had patchy to generalized alopecia, often distributed over the head, neck, limbs, and trunk; microscopic lesions included epidermal crusts and cutaneous nodules with mild perifollicular, lymphoplasmacytic inflammation. Dermatophilosis was most common in males younger than 1 year that were often found dead. Crusting, erythema, and alopecia occurred on the face, ears, and distal extremities. Less commonly, infectious dermatologic diseases were associated with other bacteria (n = 13; 14.8%), fungi (n = 5; 5.7%), ectoparasites (chiggers, lice, mites, and ticks; n = 11; 12.5%), and larval nematodes (n = 7; 8.0%). Population-level effects of these diseases in white-tailed deer are likely minimal; however, due to their dramatic presentation, demodicosis, dermatophilosis, and other infectious skin diseases can be of concern to hunters and, in some cases, may have zoonotic potential.

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.

Efficacy of Tea Tree Oil in the Treatment of Equine Streptothricosis.

Streptothricosis is a dermatitis characterized by matted tufts of hair and coalescing, pustular crusts that affects many livestock species, including horses. It results from cutaneous infection by the actinobacterium Dermatophilus congolensis. For economic reasons, the ailment is often treated with commercially available over-the-counter (OTC) products or home remedies rather than prescribed medications. This study aimed to determine the efficacy of tea tree oil (TTO), an essential oil of Melaleuca alternifolia, as an OTC treatment for streptothricosis. Bacteria were isolated from presumptive streptothricosis lesions on horses at a farm in Forest, Virginia. These isolates were microbiologically and genetically confirmed to be D. congolensis. The antimicrobial activity of TTO against D. congolensis isolates was determined by minimum inhibitory concentration and disc diffusion assays and compared with three OTC products advertised specifically for the treatment of "rain rot," a colloquial term for streptothricosis. A 1% TTO solution (v/v, in baby oil) and the three selected OTC products were applied to equine streptothricosis lesions to evaluate in vivo resolution of the lesions. Tea tree oil exhibited antimicrobial behavior against D. congolensis in vitro and produced marked improvement of streptothricosis lesions in vivo. These results have implications for development of TTO as a possible treatment for streptothricosis.

Dermatophilus congolensis infection in sheep and goats in Delta region of Tamil Nadu.

AIM: The study was conducted to isolate and identify Dermatophilus congolensis (DC) using conventional and molecular diagnostic techniques in scab materials collected from skin infections of sheep and goats in the Delta region of Tamil Nadu. MATERIALS AND METHODS: A total of 20 scab samples collected from 18 goats and 2 sheep from Nagapattinam, Thanjavur, and Tiruvarur districts of Tamil Nadu. Smears were made from softened scab materials and stained by either Gram's or Giemsa staining. Isolation was attempted on blood agar plates, and colonies were stained by Gram's staining for morphological identification. Identification was also done by biochemical tests and confirmed by 16S rRNA polymerase chain reaction (PCR), followed by sequencing and phylogenetic analysis of the amplified product. RESULTS: The peculiar laddering arrangement of coccoid forms in stained smears prepared from scab materials revealed the presence of DC. Isolated colonies from scab materials of sheep and goats on bovine blood agar plate were small, hemolytic, rough, adherent, and bright orange-yellow in color, but some colonies were white to cream color. Gram-staining of cultured organisms revealed Gram-positive branching filaments with various disintegration stages of organisms. 16S rRNA PCR yielded 500 bp amplicon specific for DC. Sequence analysis of a sheep DC isolate showed 99-100% sequence homology with other DC isolates available in NCBI database, and phylogenetic tree showed a close cluster with DC isolates of Congo, Nigeria, and Angola of Africa. Genes for virulence factors such as serine protease and alkaline ceramidase could not be detected by PCR in any of the DC strains isolated of this study. CONCLUSION: The presence of dermatophilosis in Tamil Nadu was established from this study.

Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep.

Abstract The temporal patterns of dermal immune cell influx were compared in mice and sheep, species reputedly resistant and susceptible, respectively, to infection with Dermatophilus congolensis. In both species, the response involved early mast cell degranulation, vasodilatation and an influx of dendritic cells which accumulated and apparently differentiated beneath the infected epidermis. A concomitant dermal invasion by neutrophils and T and B lymphocytes led to epidermal infiltration, particularly by neutrophils and thence to the formation of the surface scab. Hypertrophy of the epidermis also indicates keratinocyte involvement in the host response. The duration of the response, however, was considerably shorter in the mouse (about 5 days) and B cells' were the predominant lymphocyte under and adjacent to the lesion. During the more protracted response in the sheep (> 21 days), T cells, including T19 antigen +γδ T cells, outnumbered B cells. Résumé- Des modifications dans les populations des cellules immunes dans le derme sont comparées chez la souris et le mouton, espèces respectivement résistantes et sensibles à Dermatophilus congolensis. Dans ces deux espèces, la réponse fait intervenir d'abord la dégranulation des mastocytes, la vasodilatation et l'arrivée de cellules dendritiques qui s'accumulent et se différencient apparemment sous l'épiderme infecté. Une invasion concomittente dermique par des neutrophiles, des lymphocytes T et B est observée et aboutit à l'infiltration épidermique, particulièrement par les neutrophiles et pour cette raison, à la formation de croûtes superficielles. L'hypertrophie de l'épiderme indique aussi l'implication du kératinocyte dans la réponse de l'hôte. Cependant, la durée de cette réponse, est bien plus courte chez la souris (environ 5 jours) et les lymphocytes B sont les lymphocytes prédominants, sous-jacents à la lésion. Chez le mouton, la réponse est prolongée (plus de 21 jours) et les lymphocytes T, incluant les lymphocytes CD 19 et γδ surpassent en nombre les lymphocytes B. [Sasiak, A.B., Lloyd, D.H., McEwan Jenkinson, D., Kitson, S., Elder, H. Y. Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Particularités de la population cellulaire immunitaire aux sites d'infections expérimentales à Dermatophilus congolensis chez la souris et le mouton). Veterinary Dermatology 1996; 7: 59-66.] ResumeAn Se compararon los patrones temporales de llegada de células inmunitarias en el ratón y en la oveja, especies consideradas resistentes y susceptibles, respectivamente a la infección por Dermatophilus congolensis. En ambas especies la respuesta implicó degranulación temprana de mastocitos, vasodilatación y llegada de células dendríticas que se acumulaban y aparentemente diferenciaban bajo la epidermis infectada. La invasión dérmica concomitante por netrófilos y linfocitos T y B llevó a una infiltración epidérmica, especialmente por neutrófilos y consecuentemente a la formación de una costra superficial. La hipertrofi de la epidermis también indica la implicación de queratinocitos en la respuesta del huésped. Sin embargo, la duración de la respuesta fue considerablemente más corta en el ratón (unos 5 dias) y los linfocitos B fueron la célula predominante en la zona adyacente a la lesión y debajo de ella. Durante la respuesta más prolongada en la oveja (> 21 días), las células T, incluyendo el antigeno T19, células T γδ, superaban en número las células B. [Sasiak, A.B., Lloyd, D.H., McEwan Jenkinson, D., Kitson, S., Elder, H. Y. Temporal changes in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Alteraciones temporales en las poblaciones de celulas inmunitarias en zonas cutaneas de infeccion experimental por Dermatophilus congolensis en raton y en la oveja). Veterinary Dermatology 1996; 7: 59-66.] Zusammenfassung- Die temporären Muster des Influx dermaler Immunzellen wurden bei Maus und Schaf verglichen, Tierarten, die angeblich resistent und empfänglich speziell für die Infektion mit Dermatophilus congolensis sind. Bei beiden Spezies bezog die Reaktion eine frühe Mastzelldegranulation ein, weiterhin Vasodilatation und einen Influx dendritischer Zellen, die sich unter der infizierten Epidermis anhäuften und offensichtlich differenzierten. Eine begleitende Invasion der Dermis durch Neutrophile, T- und B-Lymphozyten führte zu einer epidermalen Infiltration, besonders durch Neutrophile und von dort an zur Bildung von Oberflächenschorf. Die Hypertrophic der Epidermis zeigt außerdem eine Beteiligung der Keratinozyten bei der Antwort des Wirtstieres. Die Dauer der Reaktion jedoch war bei der Maus beträchtlich kürzer (etwa 5 Tage) und die B-Zellen waren die vorherrschenden Lymphozyten unter und angrenzend an die Läsion. Während der mehr protrahierten Reaktion beim Schaf (> 21 Tage) übertrafen die T-Zellen einschließlich T19-Antigen und gamma-delta-T-Zellen die Anzahl der B-Zellen. [Sasiak, A. B., Lloyd, D. H., McEwan Jenkinson, Kitson, S., Elder, H. Y. Temporal chnges in the populations of immune cells at the site of experimental Dermatophilus congolensis infection in mice and sheep (Temporäre Veränderungen in den Populationen von Immunzellen an der Stelle experimenteller Infektionen mit Dermatophilus congolensis bei Maus und Schaf). Veterinary Dermatology 1996; 7: 59-66.].

Isolation and characterization of flagellar filament from zoospores of Dermatophilus congolensis.

Highly motile zoospores from Dermatophilus congolensis bovine isolates from clinical dermatophilosis in Japan were obtained by culturing at 27°C in an ambient atmosphere on heart infusion agar supplemented with 5% defibrinated sheep blood for 72h or in heart infusion broth for 48h with gentle shaking. After vigorous mechanical agitation of the zoospore suspension, the flagellar filaments detached from motile zoospores and were isolated in the clear gelatinous part of the final pellet by differential centrifugation. Typical morphology of a flagellar filament, with a width of approximately 15nm, was observed in the isolated flagellar filament by electron microscopy. A single major protein (flagellin) band with an apparent molecular mass of 35kDa was detected in the flagellar filament of D. congolensis strain AM-1 and that of 33kDa was detected in strain IT-2 by SDS-PAGE. In immunoblot analysis of whole-cell proteins from seven isolates of D. congolensis, antiserum to strain AM-1 zoospores reacted with the 35-kDa antigen band of strain AM-1, but not with any antigen band of other strains in a similar molecular mass range. In contrast, antiserum to strain IT-2 zoospores reacted with antigen bands at 33kDa from six strains, except strain AM-1. Similar strain-specific reactions of these anti-zoospore sera with isolated flagellar filaments from strains AM-1 and IT-2 were confirmed by immunoblot, indicating the presence of antigenic variations of flagellins of D. congolensis zoospores.

Severe generalized skin lesions due to mixed infection with Sporothrix schenkii and Dermatophilus congolensis in a bull from Jos, Nigeria.

Sporothrix schenkii and Dermatophilus congolensis were isolated from a bull with severe generalized skin lesions. The lesions were thick, crusty and scabby on the dorsal part while few scabby and several nodular lesions were seen on the lower limbs especially the thighs. Scab samples and exudates from the nodules were aseptically collected and processed for bacteriology and mycology. Gram stained smears revealed Gram-positive, filamentous organism that had longitudinal and transverse septa suggestive of D. congolensis. Colonies on 5% defibrinated sheep blood agar were small, rough, grayish-white, ß-hemolytic and adherent to the medium. It was catalase positive, urease positive and fermented glucose and maltose but not sucrose, lactose, mannitol, sorbitol and xylose. Colonies on Sabouraud's dextrose agar were small, round, white and opaque, delicate and smooth. It liquefied gelatin and fermented glucose and sucrose but not galactose, menite, and glycerin. The isolate was Gram-positive, cigar-shaped and yeast-like suggestive of S. schenkii. Dermatophilosis is common in domesticated ruminants while sporotrichosis is very rare in cattle. This may be the first report of bovine sporotrichosis from Africa.

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.

Surto de dermatofilose em bezerros Nelore criados extensivamente em Goiás / Dermatophilosis outbreak in Nelore calves raised extensively in Goiás, midwestern Brazil

Background: Dermatophilosis is an infectious-contagious disease of acute, subacute or chronic evolution caused by the etiologic agent Dermatophilus congolensis, and presents as hyperplastic or exudative dermatitis with crusty and scaly skin eruptions. Although it is a disease with important economic impact on Brazilian beef cattle, the reports of outbreaks in zebu cattle are restricted to the states of São Paulo and Mato Grosso do Sul. The present paper aimed to report the epidemiological, clinical, laboratorial and pathological findings of a dermatophilosis outbreak in Nelore calves raised extensively in Goiás, Midwestern Brazil. Case: An outbreak of skin lesions in Nelore calves occurred on a farm located in Cocalzinho de Goiás, Goiás, Midwestern Brazil. Fifty one (25.5%) of the 200 calves from 3-11-months-old presented cutaneous lesions. Forty nine of the calves were still suckling and two were weaned recently, and the most affected calves were offspring’s of cows with the lowest body condition score. Three severely affected calves were clinically examined presenting regular body condition score, pale pink ocular mucosa, fever (39.2-40.3°C), tachycardia (80-100 beats per minute), tachypnea (48-56 breaths per minute) and moderate presence of ticks. Skin inspection revealed crusty, elevated, non-pruritic lesions of grayish color that easily detached from the skin exposing a humid and hemorrhagic superficial lesion with pus. Lesions were widespread on the body with predominance on the face, ears, neck and dorsal region. Hematological findings of these calves presented leukocytosis (16,083 ± 1,910/µL) by netrophilia (11,121 ± 2,349/µL) and hyperfibrinogenemia (966.6 ± 208.16 mg/dL). Biochemical alterations consisted of hypoproteinemia (6.5 ± 0.5 g/dL) and a slight increase in GGT activity in two calves (28 and 19 U/L, respectively)...

Surto de dermatofilose em bezerros Nelore criados extensivamente em Goiás / Dermatophilosis outbreak in Nelore calves raised extensively in Goiás, midwestern Brazil

Background: Dermatophilosis is an infectious-contagious disease of acute, subacute or chronic evolution caused by the etiologic agent Dermatophilus congolensis, and presents as hyperplastic or exudative dermatitis with crusty and scaly skin eruptions. Although it is a disease with important economic impact on Brazilian beef cattle, the reports of outbreaks in zebu cattle are restricted to the states of São Paulo and Mato Grosso do Sul. The present paper aimed to report the epidemiological, clinical, laboratorial and pathological findings of a dermatophilosis outbreak in Nelore calves raised extensively in Goiás, Midwestern Brazil. Case: An outbreak of skin lesions in Nelore calves occurred on a farm located in Cocalzinho de Goiás, Goiás, Midwestern Brazil. Fifty one (25.5%) of the 200 calves from 3-11-months-old presented cutaneous lesions. Forty nine of the calves were still suckling and two were weaned recently, and the most affected calves were offsprings of cows with the lowest body condition score. Three severely affected calves were clinically examined presenting regular body condition score, pale pink ocular mucosa, fever (39.2-40.3°C), tachycardia (80-100 beats per minute), tachypnea (48-56 breaths per minute) and moderate presence of ticks. Skin inspection revealed crusty, elevated, non-pruritic lesions of grayish color that easily detached from the skin exposing a humid and hemorrhagic superficial lesion with pus. Lesions were widespread on the body with predominance on the face, ears, neck and dorsal region. Hematological findings of these calves presented leukocytosis (16,083 ± 1,910/µL) by netrophilia (11,121 ± 2,349/µL) and hyperfibrinogenemia (966.6 ± 208.16 mg/dL). Biochemical alterations consisted of hypoproteinemia (6.5 ± 0.5 g/dL) and a slight increase in GGT activity in two calves (28 and 19 U/L, respectively)...(AU)

Dermatophilosis in sheep raised under rotational grazing systems on irrigated pastures in the Brazilian semiarid region / Dermatofilose em ovinos criados em sistemas de pastejo rotacionado em pastagens irrigadas no semiárido brasileiro

ABSTRACT: Seventeen outbreaks of dermatophilosis are reported from three farms affecting Santa Inês and Santa Inês x Dorper sheep that were reared in irrigated areas with rotational grazing at a stocking rate of 50 to 100 sheep per hectare, in the Brazilian semiarid region. Most outbreaks occurred after rains and affected sheep of different ages, with morbidity rates of 0.77% to 31%. Clinical signs were dermatitis with crusts that stood out easily and left areas of alopecia. Dermatophilus congolensis was isolated in cultures in 5% sheep blood agar by means of Haalstras method. Histologically, the epidermis showed extensive multifocal areas of ortho and parakeratotic hyperkeratosis with intracorneal microabscesses and presence of D. congolensis. Sheep affected were isolated from the flocks and they recovered after treatment with 70,000IU of procaine penicillin G and 70mg of dihydrostreptomycin sulphate per kg of bodyweight. Dermatophilosis is a frequent endemic disease in rotational grazing systems with irrigated pastures and high stocking rates, which occurs with higher frequency after rains and can be controlled efficiently through isolation of the affected sheep, followed by application of a single dose of penicillin and streptomycin.(AU)

RESUMO: Relatam-se 17 surtos de dermatofilose em três fazendas de ovinos da raça Santa Inês e Santa Inês x Dorper criados em áreas irrigadas com pastoreio rotativo, com lotações de 50 a 100 ovinos por hectare, no município de Belém do São Francisco, Pernambuco. Os surtos ocorreram após períodos de chuvas, afetando ovinos de diversas idades, com morbidade de 0,77% a 31%. Os sinais clínicos caracterizaram-se por dermatite com formação de crostas que se destacavam com facilidade, deixando áreas de alopecia. Em culturas em meio de ágar sangue ovino a 5% foi isolado Dermatophilus congolensis. Na histologia, a epiderme apresentava extensas áreas multifocais de hiperqueratose orto e paraqueratótica, com microabcessos intracorneais e presença de D. congolensis. Os animais foram separados do rebanho e tratados com 70.000UI de benzilpenicilina procaína e 70mg de sulfato de diidroestreptomicina por kg de peso vivo e todos se recuperaram. Conclui-se que a dermatofilose é uma doença endêmica frequente em ovinos em sistemas de pastejo rotativo irrigado e altas lotações, que ocorre com maior frequência após períodos de chuva e que pode ser controlada eficientemente com isolamento dos animais seguido de uma única aplicação de penincilina e estreptomicina.(AU)

Dermatophilosis in sheep raised under rotational grazing systems on irrigated pastures in the Brazilian semiarid region / Dermatofilose em ovinos criados em sistemas de pastejo rotacionado em pastagens irrigadas no semiárido brasileiro

ABSTRACT: Seventeen outbreaks of dermatophilosis are reported from three farms affecting Santa Inês and Santa Inês x Dorper sheep that were reared in irrigated areas with rotational grazing at a stocking rate of 50 to 100 sheep per hectare, in the Brazilian semiarid region. Most outbreaks occurred after rains and affected sheep of different ages, with morbidity rates of 0.77% to 31%. Clinical signs were dermatitis with crusts that stood out easily and left areas of alopecia. Dermatophilus congolensis was isolated in cultures in 5% sheep blood agar by means of Haalstras method. Histologically, the epidermis showed extensive multifocal areas of ortho and parakeratotic hyperkeratosis with intracorneal microabscesses and presence of D. congolensis. Sheep affected were isolated from the flocks and they recovered after treatment with 70,000IU of procaine penicillin G and 70mg of dihydrostreptomycin sulphate per kg of bodyweight. Dermatophilosis is a frequent endemic disease in rotational grazing systems with irrigated pastures and high stocking rates, which occurs with higher frequency after rains and can be controlled efficiently through isolation of the affected sheep, followed by application of a single dose of penicillin and streptomycin.

RESUMO: Relatam-se 17 surtos de dermatofilose em três fazendas de ovinos da raça Santa Inês e Santa Inês x Dorper criados em áreas irrigadas com pastoreio rotativo, com lotações de 50 a 100 ovinos por hectare, no município de Belém do São Francisco, Pernambuco. Os surtos ocorreram após períodos de chuvas, afetando ovinos de diversas idades, com morbidade de 0,77% a 31%. Os sinais clínicos caracterizaram-se por dermatite com formação de crostas que se destacavam com facilidade, deixando áreas de alopecia. Em culturas em meio de ágar sangue ovino a 5% foi isolado Dermatophilus congolensis. Na histologia, a epiderme apresentava extensas áreas multifocais de hiperqueratose orto e paraqueratótica, com microabcessos intracorneais e presença de D. congolensis. Os animais foram separados do rebanho e tratados com 70.000UI de benzilpenicilina procaína e 70mg de sulfato de diidroestreptomicina por kg de peso vivo e todos se recuperaram. Conclui-se que a dermatofilose é uma doença endêmica frequente em ovinos em sistemas de pastejo rotativo irrigado e altas lotações, que ocorre com maior frequência após períodos de chuva e que pode ser controlada eficientemente com isolamento dos animais seguido de uma única aplicação de penincilina e estreptomicina.

Dermatofilose em bovinos / Dermatophilosis in cattle

O Dematophilus congolensis é o responsável pela enfermidade conhecida como dermatofilose. Esta doença infectocontagiosa pode atingir muitas espécies animais, entre elas, podem-se destacar os bovinos. A ocorrência desta patologia está associada, principalmente, a fatores ambientais como, por exemplo, longos períodos chuvosos, banhos acaricidas, assim como, lesões mecânicas e físicas sob a pele desses animais. Fatores intrínsecos ao hospedeiro como, imunossupressão e desnutrição podem agravar o quadro patológico relacionado a esta enfermidade. Esta é uma doença difundida mundialmente, no entanto, pode ser mais encontrada em países tropicais e subtropicais havendo, portanto, relação com longos períodos chuvosos. Os principais sinais clínicos relacionados a esta enfermidade são a presença de crostas secas associadas a tufos de pelos difundidos pela superfície corpórea do bovino, especialmente na região dorsolateral. O diagnóstico pode ser baseado em observação microscópica da bactéria, cultura do agente, assim como técnicas de biologia molecular. O tratamento dos animais afetados consiste em isolá-los dos demais bovinos e fazer uso da antibioticoterapia. O método mais eficaz para controlar a dermatofilose é a redução do carrapato, assim como de outros ectoparasitas, especialmente os insetos voadores, os quais possuem o papel de disseminadores da doença entre os animais de um mesmo rebanho.

The Dematophilus congolensis is responsible for the disease known as dermatophilosis. This infectious disease can reach many animal species, among them we can highlight the cattle. The occurrence of this condition is linked mainly to environmental factors such as, for example, long rainy periods, acaricides baths, as well as mechanical and physical damage under the skin of these animals. Factors intrinsic to the host as immunosuppression and malnutrition can aggravate the pathological picture related to this disease. This is a worldwide spread disease, however, can be found in tropical and subtropical countries and there is thus relationship with long rainy periods. The main clinical signs related to this disease is the presence of dried crusts associated with tufts spread by body surface of cattle, especially in the dorsolateral region. The diagnosis can be based on microscopic observation of the bacteria culture agent, as well as molecular biology techniques. Treatment of affected animals is to isolate them from other cattle and make use of antibiotic therapy. The most effective method to control the dermatophilosis.

Dermatofilose em bovinos / Dermatophilosis in cattle

O Dematophilus congolensis é o responsável pela enfermidade conhecida como dermatofilose. Esta doença infectocontagiosa pode atingir muitas espécies animais, entre elas, podem-se destacar os bovinos. A ocorrência desta patologia está associada, principalmente, a fatores ambientais como, por exemplo, longos períodos chuvosos, banhos acaricidas, assim como, lesões mecânicas e físicas sob a pele desses animais. Fatores intrínsecos ao hospedeiro como, imunossupressão e desnutrição podem agravar o quadro patológico relacionado a esta enfermidade. Esta é uma doença difundida mundialmente, no entanto, pode ser mais encontrada em países tropicais e subtropicais havendo, portanto, relação com longos períodos chuvosos. Os principais sinais clínicos relacionados a esta enfermidade são a presença de crostas secas associadas a tufos de pelos difundidos pela superfície corpórea do bovino, especialmente na região dorsolateral. O diagnóstico pode ser baseado em observação microscópica da bactéria, cultura do agente, assim como técnicas de biologia molecular. O tratamento dos animais afetados consiste em isolá-los dos demais bovinos e fazer uso da antibioticoterapia. O método mais eficaz para controlar a dermatofilose é a redução do carrapato, assim como de outros ectoparasitas, especialmente os insetos voadores, os quais possuem o papel de disseminadores da doença entre os animais de um mesmo rebanho.(AU)

The Dematophilus congolensis is responsible for the disease known as dermatophilosis. This infectious disease can reach many animal species, among them we can highlight the cattle. The occurrence of this condition is linked mainly to environmental factors such as, for example, long rainy periods, acaricides baths, as well as mechanical and physical damage under the skin of these animals. Factors intrinsic to the host as immunosuppression and malnutrition can aggravate the pathological picture related to this disease. This is a worldwide spread disease, however, can be found in tropical and subtropical countries and there is thus relationship with long rainy periods. The main clinical signs related to this disease is the presence of dried crusts associated with tufts spread by body surface of cattle, especially in the dorsolateral region. The diagnosis can be based on microscopic observation of the bacteria culture agent, as well as molecular biology techniques. Treatment of affected animals is to isolate them from other cattle and make use of antibiotic therapy. The most effective method to control the dermatophilosis.(AU)

Dermatophilosis in Nelore calves in Mato Grosso do Sul / Dermatofilose em bezerros da raça Nelore no Mato Grosso do Sul

The objective of this study was to describe two outbreaks of dermatophilosis in Nelore calves in the State of Mato Grosso do Sul with epidemiological characteristics peculiar to the Midwest. Morbidity and mortality rates were 50% and 0.0025% in the outbreak 1, and 12.5% and 10% in the outbreak 2, respectively. Only Nelore calves aging between 5 and 60 days were affected. Most cases occurred on pastures of Brachiaria brizantha during the rainy season. In both outbreaks, the signs started with skin thickening followed by weeping and crusting around the eyes and muzzle. In more severe cases, lesions disseminated throughout the face and the body, evolving to generalized marked thickening of the skin and wrinkling. Histology of skin lesions showed suppurative dermatitis and hyperkeratosis. The diagnosis was confirmed by viewing basophilic filamentous structures morphologically consistent with Dermatophilus congolensis in Gram stained smears. The treatment with streptomycin, oxytetracycline or penicillin associated with streptomycin used in calves demonstrated to be effective. The disease has been misdiagnosed, by the farmers, with hepatic photosensitization caused by Brachiaria spp. ingestion. This article discusses these results with the aim to help in the correct diagnosis of dermatophilosis, which is important to achieve the adequate treatment and effective control measures to minimize the losses caused by this disease.(AU)

O objetivo deste trabalho foi descrever dois surtos de dermatofilose em bezerros da raça Nelore no Estado de Mato Grosso do Sul com características epidemiológicas peculiares à região Centro-Oeste. As taxas de morbidade e letalidade foram de 50% e 0,0025% no surto 1 e, 12,5% e 10% no surto 2, respectivamente. Apenas bezerros da raça Nelore com idade entre 5 e 60 dias foram afetados. A maioria dos casos ocorreu em pastagens de Brachiaria brizantha durante o período chuvoso do ano. Nos dois surtos, os sinais se iniciavam com espessamento da pele, seguido por lacrimejamento e formação de crostas ao redor dos olhos e focinho. Nos casos mais graves, as lesões disseminavam-se pela face e por todo o corpo, evoluindo para acentuado espessamento generalizado da pele, com formação de dobras. As lesões de pele caracterizaram-se, histopatologicamente, por dermatite supurativa e hiperqueratose. O diagnóstico foi confirmado pela visualização de estruturas basofílicas filamentosas morfologicamente compatíveis com Dermatophilus congolensis em esfregaços corados por Gram. Os tratamentos com estreptomicina, oxitetraciclina ou penicilina associada à estreptomicina utilizados nos bezerros demonstraram ser eficientes. A doença foi confundida pelos produtores com fotossensibilização hepatógena causada por ingestão de Brachiaria spp. Este artigo discute estes resultados com vistas a auxiliar o diagnóstico correto da dermatofilose que é importante para a realização do tratamento adequado e de medidas de controle eficazes, minimizando as perdas causadas por esta doença.(AU)

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.

Dermatofilosis humana y animal. Presentación de un caso atípico y revisión de la literatura / Human and animal dermatophilosis. An unusual case report and review of the literature

La dermatofilosis es una infección causada por una bacteria Gram positiva perteneciente al orden de los Actinomycetales, llamada Dermatophilus congolensis. Se presenta como una dermatosis de carácter agudo, subagudo o crónico que afecta preferentemente al ganado pero también a una amplia variedad de animales domésticos y salvajes y al hombre. Tiene distribución universal, pero con mayor prevalencia en climas húmedos, tropicales y subtropicales. Es considerada una zoonosis menor que puede causar grandes perjuicios económicos en la industria del ganado y el cuero. Se realiza una revisión del tema junto con la presentación de un caso clínico sumamente atípico.

Dermatophilosis is an acute, subacute or chronic skin disease affecting a wide range of species of animals and man. It is caused by a Gram (+) bacteria of the order of the Actinomycetales named Dermatophilus congolensis. Presenting as an acute, subacute or chronic dermatosis affecting primarily cattle, but a wide variety of domestic and wild animals, and humans, as well. It is distributed worldwide but more prevalent in the humid tropical and subtropic areas. It is essential to emphasize the importance of this disease in livestock industry and leather production. The disease is reviewed and an unusual case is reported.

Dermatofilose em bovinos criados em regime de confinamento / Dermatophilosis In Feedlot Cattle / Dermatofilosis En Ganado Creados En Régimen Restricto

A dermatofilose é uma doença contagiosa, de caráter zoonótico, que acomete bovinos, ovinos, equinos, caprinos e suínos, causada pela bactéria Dermatophilus congolensis. O presente relato descreve aspectos epidemiológicos e clínicos, diagnóstico e tratamento da dermatofilose em oito bovinos da raça Brahman e cinco Nelore, criados em regime de confinamento, respectivamente, em Pardinho e Botucatu, Estado de São Paulo. Amostras das lesões de pele foram submetidas aos exames citológico, microbiológico e histopatológico, confirmando o diagnóstico de dermatofilose.(AU)

Dermatofilosis is a contagious disease, of zoonotic character, that affects mainly cattle, sheep, and horses but also goats and pigs, caused by bacteria Dermatophilus congolensis. The present report describes dermatofilosis clinical and epidemiologic aspects, diagnosis and treatment in eight Brahman and five Nelore cattle, kept under feedlot regimen in Pardinho and Botucatu, State of São Paulo. Skin lesions samples were submitted to cytological, microbiological and histopathological examination, and confirmed the diagnosis of dermatofilosis.(AU)

La dermatofilosis es una enfermedad contagiosa, de carácter zoonótico, que afecta principalmente el ganado, ovejas, y caballos pero también cabras y cerdos, causada por la bacteria Dermatophilus congolensis. Este informe describe los aspectos clínicos y epidemiológicos, el diagnóstico y el tratamiento de la dermatofilosis en ocho bovinos de la raza Brahman y cinco Nelore creados en régimen restricto en Pardinho y Botucatu, Sao Paulo. Las muestras de las lesiones cutáneas fueron sometidas a la examinación citológica, microbiológica e histopatológica, y confirmaron el diagnóstico de dermatofilosis.(AU)