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Environmental Stressors and Productivity of Small Ruminants in Arid and Semi-Arid Regions: Physiological, Behavioral, and Health Responses
Document Type : Review Article
Authors
1 Central laboratory expert, University of Mohaghegh Ardabili, Ardabil, Iran
2 Department of Animal Science, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran
3 Department of Animal Science, Moghan College of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran
4 Department of Molecular Biology, Virtual University of Pakistan, Lahore, Punjab, Pakistan
Abstract
Small ruminants such as sheep and goats are essential for the livelihoods of pastoral and agro-pastoral communities in arid and semi-arid regions, particularly in North Africa, the Middle East, and parts of South Asia. However, these animals are frequently exposed to harsh environmental conditions, including heat stress, water scarcity, poor feed quality, cold spells, and parasitic infestations. These stressors, individually or in combination, negatively impact animal health, productivity, and welfare. This review synthesizes recent findings on the physiological, behavioral, and immunological responses of small ruminants to major environmental stressors. The study places special emphasis on cumulative multi-stressor exposure and evaluates adaptation mechanisms in native breeds. Mitigation strategies such as nutritional interventions, water access, environmental modifications, and genetic selection are also reviewed. Heat stress disrupts feed intake and metabolism; water deprivation impairs thermoregulation and homeostasis; poor nutrition causes energy deficits and reproductive issues; cold stress and parasites further compromise immune resilience. Indigenous breeds display superior adaptability through evolved metabolic and behavioral responses. Practical mitigation approaches can alleviate these stress impacts and improve productivity in vulnerable regions. Understanding how small ruminants respond to environmental stress is critical for developing resilient livestock systems. Integrative strategies that combine improved management, environmental design, and genetic selection can enhance animal performance and ensure food security in climate-vulnerable areas.
Graphical Abstract
Keywords
Subjects
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Volume 14, Issue 1
January and February 2026Pages 29-47
- Receive Date 20 July 2025
- Revise Date 04 August 2025
- Accept Date 08 September 2025
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