Cows with stomach problems could be a big problem with the climate, a new study has found. That’s because cattle and other livestock with worms and other parasites produce more super potent greenhouse gas methane than healthy animals. According to FAO estimates, methane from cattle and other livestock will increase by 20% from 2017 to 2050. But according to a new paper published today in trends in Ecology & evolution, the increase in methane could be as high as 82% if parasite infections were taken into account. < / P > < p > this is a big difference, especially considering the extent to which domesticated livestock has contributed to climate change. Livestock account for 60% of all mammal biomass on the planet, and animal husbandry is responsible for more than 14% of human greenhouse gas emissions. In contrast, aviation accounts for only about 2% of global emissions. More worrisome, there may be a dangerous feedback loop between climate change, parasitic diseases and higher methane emissions: animals infected with parasites and bacteria release more methane over their lifetime, accelerating climate change. Parasites that infect livestock can reproduce at warmer temperatures, infect more animals, and thus continue the vicious cycle. < / P > < p > “it could be a very interesting phenomenon, or it could be an important phenomenon that we didn’t really consider,” said Vanessa ezenwa, a professor of ecology at the University of Georgia, the first author of the study. With or without infection, cattle and other hoofed herbivores known as ruminants are the largest emitters of methane. Other animals, including humans, also release methane, but ruminants have four cavities in their stomachs, so more methane is released. They have an entire space for fermenting food, where microbes that help them digest hard food produce a lot of gas that heats the earth. < / P > < p > parasite infection can lead to many changes, which may increase methane emissions of livestock. These animals grow slower, which leads to more lifetime emissions, because they take longer to develop enough to be slaughtered by humans. Infection can also reduce milk production and dairy cattle breeding efficiency. Ranchers may decide to slaughter and replace their cattle more frequently, and evidence suggests that this usually leads to more emissions than less. < / P > < p > the authors of the study pointed out that in the most extreme case proposed in the paper, methane emissions from global livestock would increase by 52% if every animal was sick. To calculate this, ezenwa and her colleagues reviewed existing studies on the effects of parasitic infections on methane production in specific animals. They used the findings to calculate the potential global impact of methane emissions. Data from the food and Agriculture Organization of the United Nations served as a benchmark for the study. < / P > < p > however, this study also has some limitations. It provides estimates rather than exact figures. The researchers used a floating proportion of potential infection prevalence because they did not have the actual global rate of parasitic infections. The actual data may vary greatly from region to region and there are data gaps. Hermias kebreab, director of the world food center at the University of California, Davis, said the results of the new study were not necessarily surprising. Kebreab was not involved in the study. “It’s common sense,” he said. < p > < p > kebraeb pointed out that the study may be most helpful in low – and middle-income countries where parasite infections are more common. North America and Europe have increased livestock production by better controlling pathogens, he said. “This is a good article that helps us remember that there is a compound problem.” < / P > < p > before infecting the host, parasites that cause trouble to cows will grow outside. Ezenwa says some worms need warmer temperatures to thrive. As climate change makes winters warmer and summers longer in some areas, the parasites have more time to develop and infect livestock, she said. < / P > < p > in the end, the new research provides the information needed for more research to address the climate crisis. This may bring a series of benefits: healthier animals and a healthier world, thus creating a better living environment for us. SpaceX beat blue origin and Northrop Grumman to win a $316 million air force contract