High Altitude Adaptation in Livestock and Poultry: Exploring Morphological, Physiological, Biochemical and Omic Insights: A Review

High altitude environments pose unique challenges for both humans and animals, necessitating a range of adaptations for survival. Livestock species indigenous to mountainous regions, such as Yaks, Tibetan sheep, Ladakhi cattle and Himalayan goats, have evolved specialized physiological, morphological and biochemical mechanisms to cope with extreme conditions like hypobaric hypoxia, temperature fluctuations and limited forage availability. These adaptations are crucial for their survival and the livelihoods of mountain communities that depend on them for resources like milk, meat and wool. Omic studies have revolutionized our understanding of high altitude adaptation in livestock. Genomic analyses have revealed genetic signatures of adaptation, such as higher heterozygosity rates in Yaks and positive selection of genes related to energy metabolism and hypoxia response. Transcriptomics studies have uncovered gene expression patterns and pathways underlying high-altitude responses, including those related to oxygen transport, immune function and stress tolerance in sheep and goats, comparative RNA molecule analyses have identified key regulators of hypoxia adaptation and cellular metabolism. Skin transcriptomics studies have highlighted genes involved in coat color, UV protection and fiber quality adaptations. Overall, leveraging omics methods such as genomics, transcriptomics and comparative analyses provides valuable insights into the genetic, molecular and physiological basis of high altitude adaptation in livestock. These findings contribute to the development of targeted breeding strategies and sustainable management practices essential for livestock resilience and food security in mountainous regions amidst climate change challenges.