Anagen Defluxion in Two Horses

Abstract— Anagen defluxion is an unusual cause of non-pruritic alopecia in many species. Two cases are described in horses, the onset coinciding with upper respiratory disease associated with pyrexia. Skin biopsies showed typical changes with follicles containing broken hairs of irregular shaft diameter. The alopecia resolved slowly without therapy. Résumé— L'effluvium anagène est une cause rare d'alopécie non prurigineuse dans de nombreuses espèces. Deux cas ont été obserés chez des chevaux. Le début a coincidé avec une atteinte des voies respiratoires supérieures associées à une fièvre. Les biopsies cutanées ont révélé des lésions caractéristiques: follicules contenant des poils cassés de diamètre iérrgulier. L'alopécie s'est progressivement résorbée sans traitement. Zusammenfassung— Anagen-Deflux ist eine ungewöhnliche Ursache für eine nicht pruritische Alopezie bei vielen Spezies. Beim Pferd werden zwei Fälle beschrieben, wobei der Beginn mit einer fieberhaften Erkrankung der oberen Atemwege zusammenfällt. Hautbiopsien zeigten typische Veränderungen mit Follikeln, die abgebrochene Haare mit unregelmäßigem Schaftdurchmesser enthielten. Die Alopezie heilte langsam ohne Therapie ab. Resumen La defluxión de la fase anagenica del pelo es una rara causa de alopecia de tipo no pruriginoso en una variedad de especies. En este artículo se describe el caso de dos caballos, en los cuales el punto más agudo de la enfermedad coincide con afeccion de las vías respiratorias altas acompañada de fiebre. Las biopsias cutáneas demostraron la presencia de cambios típicos en los folículos pilosos que contenían pelos rotos o de diámetro irregular. La alopecia se resolvió de manera lenta sin ningun tipo de terapia.     

Severe alopecia due to demodicosis in roe deer (Capreolus capreolus) in Belgium

Demodex mites are part of the normal fauna of hair follicles of many, if not all, healthy mammal species. Normally these parasites live in harmony with their host, however in states of putative immunosuppression the acarids undergo excessive proliferation and cause clinical disease, which may be localised or generalised. This paper describes four cases of demodicosis in roe deer (Capreolus capreolus) with localised to generalised alopecia.     

The effects of thyroid hormones on the skin of beagle dogs

The effects of hypothyroidism on canine skin were determined by comparing morphologic, morphometric, and hair cycle differences in skin biopsy samples from 3 groups of age- and gender-matched Beagle dogs: (1) euthyroid dogs; (2) dogs made hypothyroid by administration of 131I; and (3) dogs made hypothyroid and maintained in a euthyroid state by treatment with synthetic thyroxine. After 10 months of observation, there was slower regrowth of hair 2 months after clipping in the untreated-hypothyroid dogs. Untreated-hypothyroid dogs had a greater number of follicles in telogen and fewer hair shafts (ie, a greater number of hairless telogen follicles) than did the control group. The control dogs had a greater number of telogen follicles but the same number of hair shafts as the treated-hypothyroid group. Treated-hypothyroid dogs had the greatest number of follicles in the growing stage of the hair cycle (anagen). This study suggests that, at least in Beagles, induced hypothyroidism does not affect the pelage as dramatically as has been described in naturally occurring disease. This is because normal Beagles retain hair shafts in follicles for long periods, and the alopecia of hypothyroidism appears to evolve slowly because of the prolongation of this haired telogen stage. The evaluation of thyroxine-treated hypothyroid dogs demonstrates that thyroid hormone supplementation of Beagle dogs with induced hypothyroidism stimulates hair growth.     

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).     

Figurate Erythema Resembling Erythema Annulare Centrifugum in a Ferret with Adrenocortical Adenocarcinoma-associated Alopecia

Resumen— Describimos un caso de alopecia simétrica bilateral en un hurón hembra esterilizada de 3 años. El cuadro resultó estar asociado con un adenocarcinoma adrenocortical y con concentraciones séricas elevadas de estradiol. Además el animal presentaba eritema figurado en la zona dorsolateral, lumbosacra y en la cola con caracteristicas clinicas e histopatológicas parecidas al eritema annulare centrifugum de la especie humana. El eritema figurado se trató con éxito con un producto comercial que contiene el ácido graso omega-3/omega-6. [Scott D. W., Gould, J. W., Cayatte, S. M., Lawrence, H. J., Miller, W. H., Jr. Figurate erythema resembling erythema annulare centrifugum in a ferret with adrenocortical adenocar-cinoma-associated alopecia (Eritema figurado parecido a eritema anulare centrifugum en un hurón con alopecia asociada a un adenocarcinoma adrenocortical).
Abstract— Bilaterally symmetric alopecia and vulvar enlargement is reported in a 3-year-old, spayed female ferret. The condition was ultimately shown to be associated with an adrenocortical adenocarcinoma and elevated serum estradiol concentrations. In addition, the ferret had a figurate erythema over the dorsolateral lumbosacral region and tail that was clinically and histopathologically similar to erythema annulare centrifugum in humans. The figurate erythema was successfully treated with a commercial omega-3/omega-6 fatty acid-containing product.     

Adrenal steroid hormone concentrations in dogs with hair cycle arrest (Alopecia X) before and during treatment with melatonin and mitotane

The purpose of the study was to evaluate intermediate adrenal steroid hormones (ISH) in neutered dogs with hair cycle arrest (Alopecia X) during treatment with melatonin, and to see if hair re-growth is associated with sex hormone concentrations within the normal ranges. Twenty-nine neutered, euthyroid, and normo-cortisolemic dogs were enrolled in the study (23 Pomeranians, three keeshonds, two miniature poodles, and one Siberian husky). Coat assessment and an ACTH stimulation test were performed pre-treatment and approximately every 4 months for a year post treatment. Melatonin was administered initially at 3-6 mg, every 12 h. Based on clinical progression, each dog was continued on the current dose of melatonin, given an increased dose of melatonin or changed to mitotane. Partial to complete hair re-growth occurred in 14/23 Pomeranians, and partial re-growth in 3/3 keeshond and 1/2 poodle dogs. A Siberian husky dog failed to re-grow hair. Fifteen dogs had partial hair re-growth at the first re-evaluation. Melatonin dosage was increased in eight dogs but only one had improved hair re-growth. On mitotane treatment, partial to complete hair re-growth was seen in 4/6 dogs and no re-growth in 2/6 dogs. No significant decrease in sex hormone concentrations were seen during melatonin or mitotane treatment. Concentrations of ISH in dogs with hair re-growth did not differ significantly from pre-treatment values. At the completion of the study, androstenedione, progesterone and 17-hydroxyprogesterone were still above reference ranges in 21, 64 and 36%, respectively, of dogs with partial to complete hair re-growth. In conclusion, 62% of dogs had partial to complete hair re-growth. However, not all dogs with hair re-growth had concentrations of ISH within the normal range.     

Alopecia Mucinosa (Follicular Mucinosis) in a Dog

Abstract— A 10-year-old male Labrador Retriever dog presented with alopecia and scaling that was extensive in the head and limb regions and patchy over the trunk. The major histopathological feature was degeneration of the outer root sheath with disruption of keratinocytes and formation of cystic spaces filled with mucin. A diagnosis of follicular mucinosis was made. This case report represents the first case of this syndrome in the canine species.
Résumé— Un Labrador, mâle de 10 ans est présenté pour une alopécie squameuse, extensive, de la tête, des membres, et en "taches" sur le tronc. La lésion histopathologique principale est une dégénérescence de la gaine externe du poil avec dislocation des kératinocytes et la formation d'espaces kystiques remplis de mucine. Un diagnostic de mucinose folliculaire a été fait. Ce caqs est le premier décrit chez le chien. [Bell, A., Oliver, F. Alopecia mucinosa (follicular mucinosis) in a dog (Alopecia Mucinosa (mucinose folliculaire) chez un chien).