Ultrastructure of the tongue in the African pygmy hedgehog (Atelerix albiventris), comparison within the family Erinaceidae

Abstract

The African pygmy hedgehog (Atelerix albiventris) is commonly considered as a pet animal, which makes it widely studied. This study focused on lingual morphology due to its relation to the type of food consumed. Light and scanning electron microscopy on the tongues of 3 adult male hedgehogs was performed. Five types of papillae were distinguished on the dorsal lingual surface: filiform (fork‐like), conical, fungiform, vallate and foliate. Small conical papillae covered the dorsal surface of the apex, filiform (fork‐like) papillae were found on the corpus, fungiform papillae were scattered among conical as well as fork‐like papillae. Three vallate papillae localized on the lingual radix were arranged in an inverted V shape. Taste buds were opened to the circumpapillary sulcus. Histochemical analysis of seromucous salivary glands in the radix and purely serous glands in the vicinity of the vallate papillae showed the composition of their secretions in more detail. A comparison of the ultrastructure of the tongue within the family Erinaceidae was performed, as well as to species with similar feeding habits.

Tongue microarchitecture and functional characterization of the lingual papillae in the desert hedgehog (Paraechinus aethiopicus)

“…The circumvallate papillae, on the other hand, were found only on the lingual radix. Similar findings were reported in other hedgehogs (Cizek et al, 2022; Massoud & Abumandour, 2019). They were three in number and arranged in the corners of a triangle.…”

“…Additionally, the median sulcus was not observed in the desert hedgehog. A similar observation was recorded in the long-eared hedgehog (Massoud & Abumandour, 2019), Brandt's hedgehog (Goodarzi & Azarhoosh, 2016), and the African pygmy hedgehog (Cizek et al, 2022). However, it was recorded in rodents (Davydova et al, 2017), Nile grass rat (Massoud & Abumandour, 2019), agouti (Ciena et al, 2013), Pampas deer (Erdoğan & Pérez, 2013), and Persian squirrel (Sadeghinezhad et al, 2018).…”

“…The ruminants such as goats, sheep, and cattle, possess greater numbers ranging from 12 to 18, 18 to 24, and 16 to 34, respectively (Selim & Samir, 2018). In the family Erinaceidae , three were found in the European hedgehog (Akbari et al, 2018), the lesser hedgehog tenrec (Cizek et al, 2020), Brandt's hedgehog (Goodarzi & Azarhoosh, 2016), the African pygmy hedgehog (Cizek et al, 2022), and the long‐eared hedgehog (Massoud & Abumandour, 2019). In our study, the same number of circumvallate papillae were recognized.…”

“…Both microscopic and ultrastructural analyses revealed that the lingual papillae could be differentiated according to their function. The mechanical and the gustatory represent the main forms and similar arrangement was recognized in several mammalian species such as the European hedgehog (Akbari et al, 2018), Horsfield's tree shrew (Gartiwa et al, 2021), the gray mongoose (Mahmood et al, 2022), the Egyptian long‐eared hedgehog and the Nile grass rat (Massoud & Abumandour, 2019), Wistar rat (Huțanu et al, 2022), common opossum (Okada & Schraufnagel, 2005), the Egyptian fruit bat and the Egyptian tomb bat (El‐Mansi et al, 2019), lowland tapir (Goździewska‐Harłajczuk et al, 2020), African pygmy hedgehog (Cizek et al, 2022), rakali and the greater stick‐nest rat (Humphries et al, 2023). Fork filiform papillae carrying two or three spines were described previously in other hedgehogs, including the long‐eared hedgehog (Massoud & Abumandour, 2019) and Brandt's hedgehog (Goodarzi & Azarhoosh, 2016).…”