Livestock adaptation to climate

Abstract

Change and adaptation are the phenomena of life. Throughout the existence of life on earth, biological systems have adapted and changed physiologically and morphologically to acquire a homeostasis most suitable for the demands of the environment. The genetic composition is interchangeable among organisms, and the expressions of traits are the response genes in combination to biological requirements. Human interventions changed a plethora of gene expressions by direct selection including hunting, domestication, and selecting for desirable traits. Human interventions on the biological world are moving rapidly from direct to indirect interventions through overutilization of resources and secondary effects of industrial development on the earth’s ecosystems. Extensive livestock farming has developed to having a footprint in virtually every climate zone with the subtropics and temperate zones being the most favorable. The subtropics between 30 and 34 degrees north and south of the equator are accommodating for large and small animal species. The subtropics however have a range of ecological zones and microclimates shaped by geological and atmospheric features. The range of ecological zones includes extensive rangeland varying from high rainfall grasslands to semidesert scrub regions; dense and extended savannas, summer rainfall, and Mediterranean winter rainfall; summer mean temperature of 27 °C reaching >40 °C, while the winter daytime temperature range is 5 to 12 °C. Winter snowfalls can occur at higher altitudes as far north as the Tropic of Capricorn in the Southern Hemisphere. Periodic, prolonged droughts occur throughout the subtropical zone, which is influenced by the El Niño–La Niño phenomenon that occurs in the southeastern Pacific Ocean. This issue of Animal Frontiers, Livestock Adaptation to Climate, focuses on selected aspects of extensive livestock production: grassland and savanna, genetics of small stock and large stock, nutrition, and product quality.