August 28, 2023
Global warming threatens over one billion cows with heat stress by century’s end
New research has found that if global warming continues unabated, over one billion cows worldwide could encounter heat stress by the close of this century, affecting their fertility, milk output, and survival, Al-Monitor reported.
The study revealed that nearly eight out of 10 cattle globally are already grappling with elevated body temperatures, accelerated respiration rates, drooping heads, and open-mouthed panting, symptoms indicative of severe heat stress. In tropical climates, this distressing state persists year-round for 20% of cattle.
This trend is poised to escalate if cattle farming continues its expansion across the Amazon and Congo basins. These regions are projected to witness faster temperature increases than the global average.
Should greenhouse gas emissions continue their ascent, the study anticipates that Brazil, southern Africa, northern India, northern Australia, and central America will encounter a year-round heat stress predicament by 2100.
Michelle North, lead author from the University of KwaZulu-Natal in South Africa, emphasised the pivotal role of land-use decisions in determining the scope of this challenge. She said that deforestation of tropical forests for livestock expansion is not a viable development future, because it makes climate change worse and will expose hundreds of millions more cattle to severe heat stress.
Published in Environmental Research Letters, the study envisions a dire scenario where cattle husbandry could nearly double in Asia and Latin America, and surge by more than fourfold in Africa.
If comprehensive efforts are undertaken to mitigate greenhouse gas emissions, by curbing fossil fuel usage and restraining cattle farming expansion, there’s potential to reduce the number of distressed cows by half in Asia and by 80% in Africa.
The financial implications for commercial ranchers are substantial. Already, heat stress carries a hefty annual price tag of up to US$1.7 billion in the US alone.
North noted that these ranchers often possess insurance, sturdy banking relationships, and access to loans to recover from heat-related losses. In contrast, when such climatic crises strike small-scale farmers, they face the peril of losing their livelihoods, even if the overall financial losses might appear marginal.
The study found that if greenhouse gas emissions remain high, global milk supplies could decrease by 11 million tonnes annually by 2050. Even with aggressive emission reductions, a significant portion of this loss would persist, primarily across Asia and Africa, regions already grappling with limited milk supplies.
In the immediate future, measures such as providing access to shade and fans, as well as adjusting feeding times, can alleviate the plight of overheated cattle.
– Al-Monitor
