Small Ruminants and Its Use in Regenerative Medicine: Recent Works and Future Perspectives

Abstract

Medical and translational scientific research requires the use of animal models as an initial approach to the study of new therapies and treatments, but when the objective is an exploration of translational potentialities, classical models fail to adequately mimic problems in humans. Among the larger animal models that have been explored more intensely in recent decades, small ruminants, namely sheep and goats, have emerged as excellent options. The main advantages associated to the use of these animals in research works are related to their anatomy and dimensions, larger than conventional laboratory animals, but very similar to those of humans in most physiological systems, in addition to their low maintenance and feeding costs, tendency to be docile, long life expectancies and few ethical complications raised in society. The most obvious disadvantages are the significant differences in some systems such as the gastrointestinal, and the reduced amount of data that limits the comparison between works and the validation of the characterization essays. Despite everything, recently these species have been increasingly used as animal models for diseases in different systems, and the results obtained open doors for their more frequent and advantageous use in the future. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models, with a focus on regenerative medicine, to group the most relevant works and results published recently and to highlight the potentials for the near future in medical research.

Maternal COVID-19 Vaccination and Its Potential Impact on Fetal and Neonatal Development

“…Pregnant sheep have been used to study connections between maternal allergies and offspring lung development and risk of allergies [133,134]. Sheep are also considered ideal models for studying neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases [135], and due to their susceptibility to scrapie, are widely used to study prion diseases [136,137]. Sheep are also a well-recognized biomedical model for studying immunology [138], vaccine development and safety [139,140], and have been extensively used by our group and others to study the impact of maternal inflammation during pregnancy on offspring development [141].…”

NF-κB–Dependent Snail Expression Promotes Epithelial–Mesenchymal Transition in Mastitis

“…Thus, alternative studies in laboratory and large animal models are necessary and useful for testing therapies targeting Snail. Considering the rationality of the experimental design and the degree of similarity to human structures, goats have been used as a relatively suitable substitute for rodents in the research of osteoporosis, nerve injury and regenerative medicine [ 48 , 49 , 50 ]. Given that non-neoplastic goat mammary fibrosis is more common, goat tissues may have greater potential for translational medical research on human mammary fibrosis.…”

Mesenchymal Stem Cell Studies in the Goat Model for Biomedical Research—A Review of the Scientific Literature

“…Their compact size (compared to cows) makes them attractive from herd management and milking standpoint. Nowadays, there are more than 300 breeds of domestic goats in the world, which provide essential sources of meat, milk, and fiber [ 16 , 22 ]. Cashmere goats are one of the most acclaimed breeds for their annual cashmere fiber production.…”

“…The use of large animals in these research studies presents great advantages related to their anatomy and dimensions, as they are larger than conventional laboratory animals, being quite similar to humans in most physiological systems [ 9 , 16 ]. Particularly, regarding small ruminants, they are recognized animal models for preclinical and translational studies for human biomedical research.…”