Fetal development of the segment‐specific papillary body in the equine hoof

Abstract

Fetal development of the unique papillary body and its localized peculiarities in the equine hoof are described based on the study of 51 fetuses, nine newborn foals, and five adult horses. The shape and dimensions of the dermal papillae and lamellae have a formative influence on the structure and physical quality of the corneous hoof capsule with its horn tubules and lamellae. The size and arrangement of these horn structures determine the mechanical quality of hoof horn. Proper horn quality is a prerequisite for the various functions of the hoof capsule, such as protecting the living dermis supporting the hoof capsule, shock absorption, and formation of the suspensory apparatus of the distal phalanx. Development of the segment-specific papillary body is initiated by the increasing mitotic activity of the epidermal cells invaginating the dermal surface, thus forming dermal microridges. These microridges are transformed into single dermal papillae, which are arranged in rows, or enlarged to become primary and secondary dermal lamellae. The formation of a segment-specific papillary body enables the increasing keratinization ratio in the hoof epidermis and the formation of the characteristic tubular and lamellar horn responsible for the special mechanical properties of hoof horn.

The Development of the Integumentary System in Dogs

“…Süsskind-Schwendi et al [4] reported the formation of claws in dogs. The skin and its appendages were studied in pigs by Meyer and Görgen [5], by Bragulla [6] in horses, by Bragulla et al [7] in cats and by Sengel [8] in mice. In general, this system has also been studied in mammals by Hardy [9] and in other vertebrates by OliveiraMartinez et al [10], who have focused on the molecular events that surround tissue differentiation.…”

Desenvolvimento do sistema tegumentar em bovinos com idades gestacionais estimadas de 20 a 140 dias

“…Estudos mostram ainda que fêmeas da espécie bovina com abscessos ou laminite tendem a diminuir a produção leiteira em comparação às sadias (Warnick et al 2001). Süsskind-Schwendi et al (2004) relatam o seu desenvolvimento em cães, Meyer & Görgen (1986) em suínos, Bragulla (2003) em equinos, Bragulla et al (2001) em felinos e Sengel & Mauger (1976) em camundongos. De maneira geral, esse sistema também foi estudado em mamíferos por Hardy (1992) e em alguns outros vertebrados por Oliveira-Martinez (2004) enfocando os eventos moleculares envolvidos na diferenciação dos tecidos.…”

Functional considerations regarding the angioarchitecture of the equine hoof

“…Aufgrund der großen klinischen Relevanz von Huferkrankungen waren Struktur und Funktion des Hufes stets Gegenstand unterschiedlichster Untersuchungen sowohl in der Grundlagenforschung als auch in der angewandt-klinischen Forschung. Während insbesondere Hornstruktur und Hornbildung sowie biomechanische Eigenschaften des Zehenendorgans in den letzten Jahren im Zentrum des wissenschaftlichen Interesses standen (aktuelle Arbeiten über Anatomie und Biomechanik des Hufes : Pellmann 1995, Bragulla 1996, Henke 1997, Bowker et al 1998, Douglas et al 1998, Douglas und Thomasson 2000, Bragulla 2003, Egerbacher et al 2005, sind dagegen die Erkenntnisse zur Regulation der Mikrovaskularisation in diesem hoch spezialisierten Organ nach wie vor unvollständig und zum Teil widersprüchlich.…”