Milk production in Gangetic plains has nosedived due to climate change

A Scientific Reports study attributes a sharp decline in bovine milk production in India—particularly among buffaloes in the trans-Gangetic plains—due to climatic stress linked with global warming. India is the world’s largest milk producer, so dairy losses affect consumers and rural livelihoods.

Researchers analyzed over a decade of climate and livestock data (2004–2019) across Haryana, a key milk production area. They assessed multiple climate variables, including temperatures, heavy rainfall, the temperature–humidity index, and evapotranspiration, and their relation to milk yield and overall production for buffaloes, indigenous cattle, and cross-bred cattle.

The study finds that temperatures above 38°C combined with high humidity during summer significantly reduce milk production. The effect of winter temperatures is negligible. Evapotranspiration and heatwave metrics also predict reduced productivity.

Physiological mechanisms explain why heat stress impacts milk production. Increased temperature–humidity index strains animals’ thermoregulation, leading to reduced feed intake and homeostatic responses like panting. Elevated stress hormones impair milk ejection.

Buffaloes are particularly vulnerable due to traits that increase heat absorption. The study estimates higher evapotranspiration reduces buffalo milk yield by about 1.4 litres per buffalo per day.