The differences in the ecological balance of pets are massive - depending on the type of food

Not only humans, but also animals cause a CO₂ footprint – including pets, of course. In view of the huge number of dogs and cats that live on planet earth with masters and mistresses, the "pets" are a relevant topic in the context of the climate change discussion.

26 million cats and dogs live in Germany. Elsewhere there are significantly more animal lovers. An estimated 77 million dogs and more than 58 million cats live in the United States. Brazil has more than 52 million dogs and China has a good 53 million cats. Domestic animals alone eat a million tons of meat every year. And that the production of meat is responsible for the emission of significant amounts of CO₂ has been known for years in connection with human nutrition.

Brazilian scientists have now taken a closer look at the influence of animal nutrition on the CO₂ footprint. They present their results in the journal "Scientific Reports". The team led by Marcio Brunetto from the University of Sao Paulo analyzed 618 different foods for dogs and 320 for cats. Both commercially available ready-made feed and diets prepared by the animal owners themselves were taken into account.

The scientists determined balances for the amounts of greenhouse gases released in each case as well as the consumption of water and land caused by the production of food.

The central result of the analyzes can be summed up in one sentence: Dry food for dogs and cats has a significantly smaller impact on the climate than moist food. In principle, this also applies to food prepared by the animal owner himself, even if this turns out to be a bit better in terms of the climate balance.

Overall, the authors of the study came to the conclusion that a dog that weighs ten kilograms and consumes an average of 534 calories a day causes an annual carbon footprint of 828 kilograms – if it is fed exclusively dry food. However, if the dog takes in the same amount of calories through moist food, i.e. food containing meat, it is 6541 kilograms of carbon dioxide per year. So the difference is a dramatic 689 percent.

The new study will encourage those pet owners who have already relied on meatless or even vegan food for their four-legged friends. One argument against not eating meat is the concern that the animals are not getting enough protein. But insect-based protein-rich dog food can be a solution here. In the meantime, pet food made from insects can even be bought in some supermarkets.

In 2020, a research team led by Professor Matthias Finkbeiner from the Technical University of Berlin presented a life cycle assessment for four-legged friends. According to this, an average dog weighing 15 kilograms emits 8.2 tons of CO₂ over the course of 13 years of life. As we now know, this value can be significantly reduced by changing your diet.

However, two other values ​​that Finkbeiner also calculated should not change: the average dog excretes around one ton of faeces and almost 2000 liters of urine in its lifetime.