The tongue is a fundamental organ in feeding, vocalization, and grooming. It is characterized by evolutionary adaptations reflected by diet, habitat, and function. Rodents are a very diverse mammalian order and the tongue's morphology varies in size, form, and presence of papillae. This work aimed to describe the morphological and ultrastructural aspects of the tongue of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831). Tongues of Spix's yellow-toothed cavies were analyzed with light microscopy, scanning, and transmission electron microscopy. The results showed that the tongue was divided into apex, body, and root. There were different types of papillae, such as vallate, foliate, laterally placed fungiform, fungiform, filiform, and robust filiform. The epithelium was organized into layers, including keratinized, granulous, spinous, and basal, below were lamina propria, and musculature, which evolved mucous and serous gland clusters. The tongue of Spix's yellow-toothed cavy was structurally and ultrastructurally similar to other rodents and had papillae with similar morphologies to other Caviidae species. However, the presence of robust filiform papillary lines and laterally placed fungiform papillae showed the main differences from other species. This was the first description of the tongue of Spix's yellow-toothed cavy.

The mdx mouse is an experimental model of Duchenne muscular dystrophy, a genetic disorder characterized by progressive muscular degeneration which affects the oral cavity musculature, and promotes difficulty in swallowing. This study aimed to describe morphological, structural, and ultrastructural changes in the tongue mucosa and musculature of mdx mice. Forty six-month-old mice were divided into two groups: Control C57bl/10 (n = 20) and mdx C57bl/10mdx (n = 20). The tongue was dissected and analyzed with light microscopy, scanning electron microscopy, and transmission electron microscopy techniques. Our results showed conical and triangular filiform, fungiform, foliate, and vallate papillae, and their connective tissue cores. The epithelium layers identified were corneum, granulosum, spinosum, and basale. The mdx group had a thicker epithelium. Lamina propria was composed of reddish and greenish collagen. In mdx, collagen was present in the musculature of the tongue's body and in the muscular tissue between mucous and serous glands of the caudal region. Musculature was also characterized by a shorter length of sarcoplasmic invaginations, myocytolysis in mitochondrial groupings, and inflammatory focus. In conclusion, the tongue of 6-month-old mdx mice had morphology, structure, and ultrastructure revealed, showing higher wear of filiform papillae indirect reflex from the muscular degeneration process.

In young new Ethiopian immigrants (EI, about 0·5 years since immigration; n 20), veteran Ethiopian immigrant students (ES, about 13 years since immigration; n 30) and native Israeli students (NS; n 82), dietary macronutrients and electrolytes, and responses to basic tastes were compared in a cross-sectional design. From EI, to ES, to NS, dietary energy, protein, fat, and Na+ increase, whereas carbohydrates, K+ and Ca2+ do not differ. Corrected for energy intake, only Na+ increases. EI consume less dietary Na+, like foods with less Na+ content, salt their food less, yet show a greater hedonic response to salt taste. In contrast, preference for sweet does not differ. Taste psychophysics, 6-n-propylthiouracil (PROP) responses and lingual fungiform papillae density differ by group (and sex), but do not relate to dietary intake. Together, these changes could reflect dietary acculturation, increasing overall intake, Na+ in particular, accompanied by decreasing taste sensitivity, and changes in sensory perception and preference in these Ethiopian immigrants. The fact that immigrants find salt more hedonic, yet eat less of it, could suggest increased sensitivity to its taste, and might suggest restoring sensitivity to reduce Na+ intake for all. Similar alterations in taste sensory responses might be obtained in other forms of dietary flux. Understanding dietary acculturation can focus efforts (e.g. on Na+), to anticipate the disease burden of diets of affluence among immigrants. Yet, these immigrants’ nutrition is healthier in its low fat and Na+, suggesting that nutritional advice should focus on preservation, as well as prevention. Our study adds Ethiopian nutritional acculturation to that of the varied immigrant groups around the world.