Treponema spp. spirochetes and keratinopathogenic fungi isolated from keratomas in donkeys.

Keratoma is an aberrant keratin mass thought to originate from epidermal horn-producing cells interposed between the stratum medium of the hoof wall and the underlying third phalanx. The cause is unknown, although the presence of keratomas is frequently associated with chronic irritation, focal infection, or trauma. A total of 167 donkeys with keratomas were presented in this study. The diagnosis of a keratoma was based on clinical signs, radiography, and histopathologic examination. Surgical excision was attempted on all donkeys with lameness unless euthanasia was advised. Histopathologic examination, including Giemsa, periodic acid Schiff, and Young's silver special histochemical stains, was performed and showed the presence of fungal hyphae and spirochete bacteria within the degenerate keratin. Polymerase chain reaction (PCR) for treponeme bacteria was performed on 10 keratoma lesions and 9 healthy pieces of hoof (controls). All healthy donkey tissues were negative for the 3 recognized digital dermatitis (DD) treponeme phylogroups, whereas 3 of 10 (30%) donkey keratoma samples were positive for one of the DD treponeme phylogroups. Routine fungal culture and PCR for fungi were performed on 8 keratoma lesions and 8 healthy pieces of hoof (controls). Keratinopathogenic fungi were detected in 1 of 8 (12.5%) keratomas, while only non-keratinopathogenic, environmental fungi were detected in 8 control healthy hoof samples. This is the first time the DD treponemes phylogroup and keratinopathogenic fungi have been detected in keratomas. Further studies are required to assess the significance of this finding.

Three-dimensional printed surgical guides for keratoma removal in horses using computed tomography or magnetic resonance imaging-based segmentation.

OBJECTIVE: To report the technique, surgical approach, and postoperative features in horses treated via a 3-dimensional (3D) printed guide-assisted keratoma resection created using computed tomography (CT) or magnetic resonance imaging (MRI)-based segmentation. ANIMALS: Five client-owned horses. STUDY DESIGN: Short case series. METHODS: Horses were placed under general anesthesia for imaging (CT and MRI) and underwent a second anesthesia for surgery. Two horses had guides created from CT-based imaging, 3 horses had guides created from MRI. Various sized nonarbored hole saws were used to create accurate and precise portals for keratoma removal. Surgical sites were managed until keratinized granulation tissue had formed and the defect was sealed with an artificial hoof wall patch. RESULTS: All keratomas were successfully removed as a single piece either intact with the hoof wall or easily extracted after the hoof wall portal was created in a surgical time between 20 and 90 min. All CT created guides fitted without issue; MRI-created guides required minor adjustments with a rotary device for proper fit. All cases had minor debridement adjacent to P3 and circumferential lamellar tissue. All horses returned to previous level of performance 2 to 4 months postoperatively. CONCLUSION: Use of 3D printed guides led to accurate targeting of keratomas with small surgical portals and short surgical times. Due to challenges with MRI-based segmentation, CT is preferred.

Efficacy of cryotherapy in the treatment of cutaneous horn associated with papillomatosis in a dog.

Cutaneous horn is a skin disease with low incidence and few citations in the literature. This report describes a dog with multiple cutaneous lesions of papillomatosis and one giant cutaneous horn on the face. Two sessions of cryotherapy achieved complete remission of the lesions.

La corne cutanée est une maladie de la peau à faible incidence et peu citée dans la littérature. Cet article décrit un chien avec de multiples lésions cutanées de papillomatose et une corne cutanée géante sur la face. Deux séances de cryothérapie ont permis d'obtenir une rémission complète des lésions.

Los cuernos cutáneos son una lesion patológica de baja incidencia y con escasas menciones en la literatura. Este artículo describe un caso de un perro con multiples lesiones cutáneas de papilomatosis y un cuerno cutáneo gigante en la cara. Dos sesiones de crioterapia consiguieron una remisión completa de las lesiones.

O corno cutâneo é uma doença cutânea com baixa incidência e poucas citações na literatura. Este relato descreve um cão com múltiplas lesões cutâneas características de papilomatose e um corno cutâneo gigante na face. Houve remissão completa das lesões após duas sessões de crioterapia.

Platelet-rich Plasma Combined With a Sterile 3D Polylactic Acid Scaffold for Postoperative Management of Complete Hoof Wall Resection for Keratoma in Four Horses.

Keratoma is a nonmalignant horse tumor that grows in the space between the horn of the hoof and the distal phalanx. Keratoma causes lameness in the horse, and surgical excision is the treatment of choice. Four horses underwent removal of a keratoma by complete hoof wall resection. The remaining wound was treated with platelet-rich plasma (PRP) combined with a sterile three-dimensional polylactic acid scaffold. The PRP was applied at 3, 6, 9, 12, 15, and 18 days postoperatively. The surgical site was cleaned with gauzes and swabs soaked in Ringer's lactate solution before applying PRP and the foot bandage. Healthy granulation tissue developed at 6-21 days postoperatively. The hoof wall defect was completely filled with new hoof wall within 6-8 months after surgery. All horses returned to their previous exercise level, and no recurrence of lameness was reported by the owner.

Association between teat-end hyperkeratosis and mastitis in dairy cows: A systematic review.

A systematic review was conducted to elucidate the role of teat-end hyperkeratosis (THK) as a risk factor for clinical mastitis (CM) or subclinical mastitis (SCM). Scientific papers on the subject were identified by means of a database search. All types of peer-reviewed analytical studies, observational or experimental and published in English, could be included in the review, regardless of publication year. Of 152 identified records, 18 articles were selected, of which 8 were prospective cohort studies, 9 were cross-sectional, and 1 was a hybrid case-control study. Internal validity of studies was assessed using a score system ranging from 0 to 6, based on design, risk of bias, and statistical methods. The most frequent study limitation was improper use of statistical methods to avoid confounding of associations between THK and CM or SCM. The 3 studies that used CM as outcome (all with high validity scores) showed positive associations with THK (especially severe), although the magnitude and statistical significance of the estimates differed among them. Most studies that used SCM as the primary outcome (based on microbiological examination of milk) reported that only severe THK was associated with SCM. Two studies with high validity scores reported moderate to strong associations between severe THK and incidence or prevalence of Staphylococcus aureus intramammary infection. Two studies with high validity scores reported that only severe THK was associated with the risk of somatic cell count (SCC) ≥200,000 cells/mL and increased mean SCC, respectively. Although 4 cross-sectional studies reported positive associations between THK and SCC, these associations were possibly spurious because confounding factors, such as parity, were not considered in the analyses. Results of the reviewed studies suggest that severe THK is a risk factor for both CM and SCM, as defined by microbiological examination of milk, SCC thresholds, or mean SCC. The effect of severe THK on both contagious (especially Staphylococcus aureus) and environmental CM or SCM emphasizes the importance of teat health for mastitis control. Four studies demonstrated that quarters with mild THK had lower prevalence of intramammary infection or lower mean SCC than quarters with no THK, suggesting that development of mild THK, as a physiological response to milking, can have a protective effect. Dairy consultants should focus on monitoring and minimizing occurrence of severe THK to prevent CM and SCM.

Outcome following computed tomographic imaging and subsequent surgical removal of keratomas in equids: 32 cases (2005-2016).

OBJECTIVE To describe the use of CT in the diagnosis of and presurgical planning for equids with keratomas treated by hoof wall resection and determine postoperative complications and outcome. DESIGN Retrospective case series. ANIMALS 29 horses and 3 mules with keratomas treated by partial or complete hoof wall resection following CT imaging of the distal portion of the affected extremity from 2005 through 2016. PROCEDURES For each equid, physical examination and lameness evaluation were performed, followed by imaging of the distal portion of the affected extremity. A tentative diagnosis of keratoma was made given results of clinical, radiographic, and CT examination, with the definitive diagnosis made on histologic examination. After CT imaging, each equid was treated with hoof wall resection. RESULTS CT allowed accurate identification of the size and location of 35 keratomas in 33 feet. Thirty equids underwent partial and 2 underwent complete hoof wall resection for keratoma removal. Complications developed in 4 of 31 (13%) equids and included excessive granulation tissue formation at the surgical site (n = 1), excessive granulation tissue formation and worsening lameness (1), incomplete keratoma removal with suspected regrowth (1), and incomplete healing of the surgical site with distal interphalangeal joint sepsis secondary to repeated debridement of abnormal tissue (1). Twenty-eight of 31 (90%) equids returned to their previous activity level. CONCLUSIONS AND CLINICAL RELEVANCE Preoperative CT examination of the feet was useful in the diagnosis of and surgical planning for keratomas in equids. A low complication rate was achieved with the described techniques.

Control of canine idiopathic nasal hyperkeratosis with a natural skin restorative balm: a randomized double-blind placebo-controlled study.

BACKGROUND: Nasal hyperkeratosis may cause discomfort in dogs by predisposing them to fissures and secondary bacterial infection. Approaches to treatment have been described anecdotally; the effectiveness of such therapies remains unproven. HYPOTHESIS/OBJECTIVES: To investigate the efficacy of a balm containing essential oils and essential fatty acids in dogs with idiopathic nasal hyperkeratosis. ANIMALS: Client-owned dogs with noncomplicated nasal hyperkeratosis. METHODS: The study was conducted as a randomized, double-blind, placebo-controlled clinical trial with parallel group design and two month follow-up period. Dogs received daily topical application of a commercial balm product (group DBB) or placebo (aqueous gelling agent with preservatives, group PB). The main outcome variables were lichenification, dryness, suppleness and extent of lesions. Subjective owner satisfaction index score was a secondary variable. Evaluation was performed on days (D)0, 30 and 60. Response to treatment was assessed as the change from baseline to each examination day for each criterion. RESULTS: Forty eight dogs, principally French (26 of 48) and English (seven of 48) bulldogs, were included and 39 completed the study. No major adverse events were reported. On D60, changes from baseline for lichenification, lesion extent, suppleness and total score were -31.2%, -18.3%, -72.8% and -36.8% in group DBB (23 dogs) and -11.9%, 2.3%, -42.1% and -14% in group PB (16 dogs), respectively. The total score was significantly improved on D60 in group DBB compared to PB (Wilcoxon-Mann-Whitney U-test, P = 0.0016). CONCLUSIONS AND CLINICAL IMPORTANCE: The balm proved safe and helpful in managing canine idiopathic noncomplicated nasal hyperkeratosis.

Effect of a multi-sided concave liner barrel design on thickness and roughness of teat-end hyperkeratosis.

In a round liner barrel, the force of the closing liner is transferred by the two opposite sides of the liner wall to the teat apex. Liners with a multi-sided barrel shape close at three or more planes and distribute their force to a larger area of the teat apex. The objective of the study was to investigate effects of a liner with a multi-sided concave barrel design on the degree of teat-end hyperkeratosis, thickness and roughness, and on the time delay until thickness or roughness of teat-end hyperkeratosis responded to the experimental liner. The investigations were done on two dairy farms, one in USA and one in Germany. A split-udder arrangement of liners was used, and control treatment was a liner with round barrel shape. The test period comprised 14 weeks in the first study and 16 weeks in the second study. Thickness of teat-end hyperkeratosis was influenced by farm and test week. Roughness was influenced by farm, test week and treatment. In the first study, the incidence of rough teat-end hyperkeratosis was about 28 and 42% lower in teats milked with the experimental liner than in teats milked with the control liner by test weeks 11 and 14, respectively. In the second study, incidence of rough teat-end hyperkeratosis was rare in general, and in addition hardly occurred in teats milked with the experimental liner. The results indicate that the barrel design of the experimental liner causes similar effects on different farms but magnitude of the effect depends on initial incidence of teat end hyperkeratosis in the herd.

Ramps and hybrid effects on keel bone and foot pad disorders in modified aviaries for laying hens.

Non-cage systems provide laying hens with considerable space allowance, perches and access to litter, thereby offering opportunities for natural species-specific behaviors. Conversely, these typical characteristics of non-cage systems also increase the risk of keel bone and foot pad disorders. The aim of this study was twofold: 1) to investigate if providing ramps between perches (housing factor) reduces keel bone and foot pad disorders and 2) to test for genetic predisposition by comparing 2 different layer hybrids. In a 2 × 2 design, 16 pens were equipped either with or without ramps between perches and nest boxes (8 pens/treatment), and housed with either 25 ISA Brown or Dekalb White birds per pen (in total 200 birds/hybrid). Keel bone injuries and foot health were repeatedly measured via palpation and visual assessment between 17 and 52 wk of age and daily egg production was recorded. The relationships between the dependent response variables (keel bone and footpad disorders, egg production) and independent factors (age, ramps, hybrid) were analyzed using generalized linear mixed models and corrected for repeated measures. Ramps reduced keel bone fractures (F1,950 = 45.80, P < 0.001), foot pad hyperkeratosis (F1,889 = 10.40, P = 0.001), foot pad dermatitis (F1,792 = 20.48, P < 0.001) and bumble foot (F1,395 = 8.52, P < 0.001) compared to pens without ramps. ISA Brown birds sustained more keel bone fractures (F1,950 = 33.26, P < 0.001), had more foot pad hyperkeratosis (F1,889 = 44.69, P < 0.001) and laid more floor eggs (F1,1883 = 438.80, P < 0.001), but had fewer keel bone deviations (F1,1473 = 6.73, P < 0.001), fewer cases of foot pad dermatitis (F1,792 = 19.84, P < 0.001) and no bumble foot as compared to Dekalb White birds. Age, housing and hybrid showed several interaction effects. Providing ramps proved to be very effective in both reducing keel bone and foot pad problems in non-cage systems. Keel bone and foot pad disorders are related to genetic predisposition. These results indicate that adaptation of the housing systems and hybrid selection may be effective measures in improving laying hen welfare.

Solar keratoma: An atypical case.

This case report shows that keratomas can occur in both hind feet of equine patients and should be considered as a diagnosis for long-standing, intermittent lameness localised to the hooves. A Thoroughbred racehorse presented with long-standing abscessation of the right hind hoof. Owing to the long-standing nature, the abscess draining tract was surgically explored. A focal mass was found within the solar horn. Histopathology revealed the mass to be a keratoma. A similar mass was removed from the left hind hoof a few months later after similar presenting signs. This case shows that keratomas can occur in more than one hoof within a short period and should be considered a differential diagnosis for long-standing lameness localised to the hoof.

Changes in teat-end hyperkeratosis after installation of an individual quarter pulsation milking system.

The objective of this study was to examine changes in teat-end hyperkeratosis (HK) in a herd transitioning from a standard pulsation milking system to an individual quarter pulsation milking system. The Milpro P4C (Milkline, Gariga di Podenzano, Italy) system stops milking individual quarters using an individual quarter pulsation milking system with 4 independent pulsation channels per cluster instead of 2. Teat-end HK was evaluated immediately after cluster removal using a scoring system where N signifies no ring; S signifies a smooth, raised ring; R signifies a rough ring; and VR signifies a very rough ring. Scorings were classified for 69 cows (48 Holstein, 12 crossbred, and 9 Jersey) on 5 dates relative to installation of the Milpro P4C system on April 28, 2011, as follows: April 7 (PRE1); April 21 (PRE2), May 12 (POST1), May 26 (POST2), and June 9 (POST3). Hyperkeratosis classifications were converted to numerical scores as follows: N=1, S=2, R=3, and VR=4. The MIXED procedure of SAS (SAS Institute Inc., Cary, NC) was used to evaluate fixed effects of age, breed, parity, teat position, and all interactions on teat-end HK score with variables repeated by scoring with cow within breed as subject. The effects of teat position and scoring × breed on teat-end HK score were significant. Holstein HK scores improved from PRE2 to POST3 (1.64 ± 0.09 and 1.42 ± 0.10, respectively), POST1 to POST3 (1.59 ± 0.10 and 1.41 ± 0.10, respectively), and POST2 to POST3 (1.53 ± 0.10 and 1.42 ± 0.10, respectively). Crossbred HK scores did not differ among scorings. Jersey HK scores worsened from POST1 to POST3 (1.32±0.21 and 1.63 ± 0.22, respectively). For all cows included in the final analysis, right front and left front HK scores were higher than right rear and left rear HK scores (1.58 ± 0.09, 1.62 ± 0.09, 1.37 ± 0.09, and 1.36 ± 0.09, respectively). However, a significant decrease in teat-end HK scores for Holsteins did occur from PRE1 to PRE2 (1.75 ± 0.10 and 1.63 ± 0.10, respectively) and may represent biological variation in teat-end HK over time unrelated to installation of the individual quarter pulsation system. Individual quarter pulsation milking systems may prevent overmilking and reduce HK in Holstein cows. Further research is warranted to understand the breed differences observed in this study.

The effect of perches in cages during pullet rearing and egg laying on hen performance, foot health, and plumage.

Enrichment of pullet cages with perches has not been studied. Our objective was to determine if access to metal perches during all or part of the life cycle of caged White Leghorns affected egg traits, foot health, and feather condition. Treatment 1 represented control chickens that never had access to perches during their life cycle. Treatment 2 hens had perches only during the egg laying phase of the life cycle (17 to 71 wk of age), whereas treatment 3 chickens had perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens always had access to perches (0 to 71 wk of age). Comparisons between chickens that always had perches with controls that never had perches showed similar performance relative to egg production, cracked eggs, egg weight, shell weight, % shell, and shell thickness. More dirty eggs occurred in laying cages with perches. Feed usage increased resulting in poorer feed efficiency in hens with perch exposure during the pullet phase with no effect during egg laying. Perches did not affect hyperkeratosis of toes and feet. The back claw at 71 wk of age broke less if hens had prior experience with perches during the pullet phase. In contrast, during egg laying, the back claw at 71 wk of age broke more due to the presence of perches in laying cages. Perches in laying cages resulted in shorter trimmed claws and improved back feather scores, but caused poorer breast and tail feather scores. In conclusion, enriching conventional cages with perches during the entire life cycle resulted in similar hen performance compared with controls. Fewer broken back claws but poorer feed efficiency occurred because of prior experience with perches as pullets. Perch presence during egg laying improved back feather scores with more trimmed nails but caused more dirty eggs, broken back claws, and poorer breast and tail feather scores. Although perches allow chickens to express their natural perching instinct, it was not without causing welfare problems.

Nonseptic diseases associated with the hoof complex: keratoma, white line disease, canker, and neoplasia.

This article addresses nonseptic diseases associated with the hoof complex, namely keratoma, white line disease, canker, and neoplasia. Keratoma is an uncommon cause of lameness, which may be surgically removed. White line disease, a keratolytic process on the solar surface of the hoof, is treated with therapeutic farriery and resection of the hoof wall when appropriate. Equine canker is an infectious process that results in development of a chronic hypertrophy of the horn-producing tissues. Neoplasia involving the equine foot is rare, and melanoma is the most common type of neoplasm reported.

Characterization of a novel papillomavirus species (ZcPV1) from two California sea lions (Zalophus californianus).

A seven-year old California sea lion (Zalophus californianus) presented with focally extensive, bilaterally symmetric, proliferative axillary skin lesions and preputial lesions. A second California sea lion in the same population presented with similar proliferative lesions on the underside of the tail. Histopathology revealed epidermal hyperplasia with severe hyperkeratosis, with proliferating keratinocytes forming broad, branching pegs that extended into the dermis. Pan-papillomaviral consensus PCR was used to obtain initial E1 sequence template and the complete genome was determined using a combination of rolling circle amplification and specific-primer PCR. Analysis revealed a novel papillomavirus, Zalophus californianus papillomavirus 1 (ZcPV1), with seven open reading frames encoding five early proteins (E6, E7, E1, E2 and E4) and two late proteins (L1 and L2). Phylogenetic analysis revealed that (ZcPV1) is most closely related to Equine papillomavirus 1 (EcPV1) in the genus Zetapapillomavirus, and Canine papillomaviruses 3 and 4 (CPV3, CPV4) in the genus Chipapillomavirus. The lesions regressed without intervention over a period of several months.

Computed tomography or magnetic resonance imaging-assisted partial hoof wall resection for keratoma removal.

OBJECTIVES: To (1) describe the computed tomography (CT) and magnetic resonance imaging (MRI) appearance of keratomas; (2) describe a CT- or MRI-assisted partial hoof wall resection technique for removal of keratomas; and (3) evaluate the morbidity and postoperative outcome of these horses. STUDY DESIGN: Case series. ANIMALS: Horses (n=10) with keratoma. METHODS: Data retrieved from medical records included signalment, lameness duration and grade, physical and diagnostic evaluation findings, CT and MRI technique and findings, surgical details, histopathologic diagnosis, postoperative treatment, and complications experienced. Long-term outcome was obtained by telephone interviews of owners. RESULTS: Complications including excessive granulation tissue formation and infection were seen in 2 horses (20%). No keratoma recurrence occurred. Follow-up information was available for 8 horses; 7 were sound and had resumed work. Mean time until they became sound was 2.7 months, and mean time until work resumed was 3.6 months. CONCLUSIONS: CT and MRI can be used to accurately identify the location of keratomas. Postoperative complications may be decreased by creating smaller hoof wall defects, filling the defects with antimicrobial-impregnated polymethylmethacrylate, and placing a shoe early in the postoperative period.

Multiple keratomas in an equine foot.

A 19-year-old, Arabian gelding was presented for left hindlimb lameness and deviation of the hoof wall. Radiographs revealed a semicircular, radiolucent area in the lateral edge of the distal phalanx. Three distinct keratomas were successfully removed following hoof wall resection.

Photodamage in feline skin: clinical and histomorphometric analysis.

The purpose of this study was to investigate clinical and histomorphometric features of cat skin under long-term solar exposure. Ear skin of 34 Domestic Shorthair cats that were chronically exposed to sun was classified as follows: group 0, normal (n = 13); group 1, initial stage of photodamage (PD) (n = 10); group 2, advanced stage of PD (n = 11). Histologic sections were examined independently by 2 pathologists, and epidermal thickness, adnexal unit area, and dermal cellularity were assessed by morphometry. A positive correlation was obtained between age, degree of edema and sclerosis in the upper dermis, telangiectases, squamatization of basal keratinocytes, and epidermis thickness and the degree of PD. The area occupied by adnexal structures in the dermis diminished with increased PD. Dermal sclerosis and edema best separated the 3 groups. The results indicated a high level of skin hypersensitivity to sun rays in cats. The findings may be useful for clinical testing and in general veterinary pathology and dermatology.

Generalized hyperkeratosis caused by Scopulariopsis brevicaulis in a Japanese Black calf.

A 6-month-old Japanese Black female calf became gradually emaciated over a 40-day period and was humanely killed. At necropsy, hyperkeratotic nodules were seen to have spread over almost the entire body surface. Scopulariopsis brevicaulis was isolated from the skin and identified morphologically and by gene sequence analysis of the D1/D2 domain of large subunit ribosomal RNA. Numerous periodic acid-Schiff-positive, lemon-shaped conidia were detected histologically in the keratinized layer and the hair follicles. The distribution of the fungal elements in the skin corresponded to that of the hyperkeratotic lesions. This is the first report of a disease caused by S. brevicaulis in animals. Previously reported human infections have not included generalized hyperkeratosis.