Climate change: Heat creates “heat stress” in farm animals

Heat stress caused by extreme heat waves, which will increase with climate change, affects humans as well as farmed and wild animals.

There is a heat threshold above which life is threatened. A study published in June 2021 in The Lancet Planetary Health serves as a reminder that this threshold certainly pertains to human beings, but not only.

If people are exposed to temperatures above 32°C with extremely high humidity or temperatures above 45°C with extremely low humidity for a long time, it can be fatal. “Explains Senthold Asseng, head of this study, on the University of Munich website.

The authors found that farm animals – such as cattle, poultry, but also all cultures of living organisms – show levels of resistance to heat stress (in the sense of physiological damage suffered) at least equivalent to those of humans.

The impact on these animals was already observed during the 2003 heat wave in France. In the west of the country, 1.7 million livestock deaths were deplored due to excessive heat. But this does not always lead to death. It is sometimes called “heat stress” – an abnormal body temperature, which can cause health problems. For example, in high humidity, moderate heat stress starts at 23 degrees for humans and 24 degrees for cattle and swine. In high humidity, heat stress starts at 27 degrees for humans and 29 degrees for cattle and swine.

The physiological consequences of heat stress

As with us, heat stress can have significant physiological consequences in these animals. For example, dairy cows suffer from severe dehydration when 12% of their body weight has been lost in the water. If they can’t get enough water during a heat wave, due to heat stress, they will produce 10-20% less milk than normal. Poultry, in turn, is affected by severe heat stress at 37 degrees: this is when hens begin to lay significantly fewer eggs. In general, prolonged or repeated heat stress causes difficulty in reproduction.

These direct effects on the animals that are close to us, and that are the source of part of our food, are significant for a much bigger problem: the threats that weigh on animal biodiversity as a whole. ” Genetic adaptation to a changing climate often takes several generations. The time available is too short for many life forms. If current climate trends persist, many living things could be severely affected or even completely disappear from Earth due to temperature change. “, warn the authors of this study.

Need for support and adaptation

The record heat wave that hit Canada in late June 2021 shows the dramatic consequences that global warming can have, particularly on health. The thermometer rose to 49.6 degrees Celsius in the small town of Lytton, before a major fire broke out there. Electric cables melted. Emergency departments across the Pacific Northwest were often overwhelmed: in British Columbia, 486 heat-related deaths.

For more

Therefore, during episodes of extreme heat with temperatures well above 40°C, ” such as those currently seen on the Northwest Coast of the United States and Canada “It is necessary to provide technical support to the populations: individual air conditioning in homes and even in air-conditioned public spaces.

This is a logistical problem that tends to increase as climate change leads to rising temperatures. ” By the end of the century, 45-70% of the Earth’s surface could be affected by climatic conditions in which humans cannot survive without technological support such as air conditioning. The authors of this study believe that this type of technological support should also be considered for farm animals, who therefore suffer as much as we do from heat stress and its dangers increased by global warming.

Climate change: Heat creates “heat stress” in farm animals

Summer falls on June 21, 2021.

Source: Pexels/Darwis Alwan (cropped photo)

Among the possible solutions, they mention: increased natural shading (e.g. trees) » and artificial shade; one ” new design of cities and buildings “, generating lower local temperatures – lighter and more reflective colors of the roof and walls, better insulation of the walls and roof, windows away from the direction of the rising and setting sun; one ” increased air circulation, indoor air conditioning and refrigeration systems “.

According to the authors, to reduce heat stress, it is a matter of ensuring that farm animals are not left outside in extreme heat, but in stables, developed from the techniques mentioned above to reduce the impact of heat stress. solar radiation and have air conditioning and ventilation systems.

For more

Source: Pixabay

Leave a Comment

Your email address will not be published.