Livestock, cattle in particular, represents «globally 14.5% of greenhouse gas emissions and it is 10% at European level», notes Jean-Louis Peyraud, director of research at the National Institute research for agriculture, food and the environment (Inrae).
In question: the methane emitted by cows after their digestion.
«When the animal feeds, it will release hydrogen in the rumen», the first stomach of ruminants where the fermentation process takes place.
«If we don’t want the cows to inflate like a balloon, they have to be able to expel it, then its bacteria transform it into methane, which the cows expel by belching», continues the researcher.
In the wake of the objectives of reducing greenhouse gases, «it is accepted that the agricultural sector will have to lower» its emissions, «but less than the industrial sector… it is easier to act on a gas pipeline than on a dairy cow», notes Mr. Peyraud.
– Fewer cows and as much production –
Among the already existing levers, extend the duration of the careers of cows, dairy cows in particular, to reduce the number of herds while maintaining the same level of production.
The first saving is made from the insemination of the cows, by carrying out «genetic sexing», which makes it possible to separate the male and female embryos to control the sex of the calf to be born and to have only wanted animals, defends Rudy Muller, Managing Director of Sexing Technology France, specialized in this sector.
Then, «when we improve the technical performance, we also improve the ecological aspect», by selecting animals that are more productive and more resistant to diseases, he argues.
But in France, the average length of a dairy cow’s career is two and a half years, while it generally reaches its best production capacities in its third and fourth year of production.
So, «better to have ten cows producing 10,000 liters than 16 which make 6,000, which will avoid raising animals to renew the animals that go to the slaughterhouse», he believes.
On the Loïc Guines farm in Ille-et-Vilaine, which has gone «from intensive to organic», to improve its carbon footprint, the breeder has also «optimized the calving of heifers at 24 months», in other words, they are inseminated as soon as their weight and age allow it so that after the birth of the calf their milk production cycle can begin.
«And all those not fertilized go to the slaughterhouse», explains the breeder.
This system makes it possible to work with older cows and not to have heifers, young cows that have never calved, which will emit greenhouse gases for two years without producing anything in return.
– The consumer as the keystone –
In parallel with the management of the herd, the animals in the pastures make it possible «to maintain the meadows, where half of the plant species in Europe live», underlines Mr. Peyraud.
«If in France and in Europe we reduced breeding a lot, which we no longer exported, given consumer demand, it would simply be produced elsewhere and by less efficient systems… In addition to shifting the problem, we will make it worse”, pleads the scientist.
But far from farms, at the other end of the food chain, «on the part of consumers, we realize that the main concern is inflation and the subject of well-being at work comes before the environment. «, according to Axel Bigot, CSR manager of the Lactalis group.
For breeders, the challenges are therefore multiple: to preserve their level of production and improve their carbon footprint, while remaining competitive.