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Testimonials and results

Testimony of Marcel Gruel, breeder of dairy cows in Brittany, in France.
Marcel Gruel
My veterinary expenses went from 150€ to 40€ per cow
Holstein breeder
Châteaugiron, FRANCE


Marcel Gruel, 52 years old is a breeder of dairy cows in Châteaugiron, in Brittany, FRANCE.


His farm : 62 hectares with 32 ha of meadows, 12 ha of wheat, 17 ha of corn, 50 dairy cows, 50 heifers. He works in this farm since 1986.


  • Bactériosol concentré (since 1999) / Fertilization of cereals and grasslands.
  • Bactériolit (since 1999) / Optimised use of effluents


Marcel Gruel has been working with SOBAC for 13 years. In Ille-et-Vilaine, in France, he was the first one to use Bactériosol and Bactériolit. As many other breeders, he discovered the firm from Aveyron at the SPACE in Rennes, the international farming Fair.

In relation to animals’ health, my ob¬servations are recent because I have changed the structure of the farm. I used to be part of a GAEC but my partner retired in 2005 so I am now in charge of everything. Up to that date we were not using Bactériosol and Bactériolit on the whole surface of the farm. When he left, I took a sharp turn and changed everything to Bactériosol and Bactériolit. Now, I can say that, year after year, my veterinary expenses are decreasing. In terms of metabolism, we can see that the rumen is working better thanks to healthier food. I also have fewer limps.


My vet expenses went from 150€ to 40€ per cow 


It is still going down. The cattle are healthier, I can see it from the way they go to and come back from the meadows. My forage has gained nutritive value by using less water. The animals are digesting better. I don’t have diarrhoea anymore when the cows are out in the meadows. During spring, when the grass is full of nitrogen and water, it is quite laxative to the cows. I have not seen that in years.


As for the structure of the soil, the suppleness of the land is much more assertive. Towards the end of winter, when you step on your fields, it feels like you are walking on carpet. And, when at the same time you walk on a traditional field, it feels like concrete. The difference is huge. When spring comes and I start working the soil, I see many worms. There is an incredible repopulation of the soil, life is coming back.


Our area is more conventional, but near Rennes it is more dynamic, and they are questioning things more. It takes time, it is our nature. Talking with colleagues, I see that they notice things and they are more and more interested in other ways to work. I have often heard: “your fields are clean; your cows don’t refuse to eat”. Often, it does not go much further than that. They are not asking me how I am doing it. It is going its way into people’s mind. I know some farmers are willing to change and take a step forward. Everything is in our heads. There are so many things to change, and so many received ideas to forget. Seeing things in a different way is not always easy. The force of habit….


At first, all I wanted to do was to enhance the value of my manure; it did not go further than that. Now, I am part of the process and


I see that I was heading straight into a wall if I had not changed


When we see that we get the same results without using any chemical inputs, we tell ourselves that we took the right path.

I have divided the nitrogen supply by two, I don’t use lime anymore. From the moment, we feel we are working in a way that seems the best for us, we feel better in our body. For my part, I am in direct contact with urbanisation and I hate to have to spray. On the other hand, it is now pleasant for me to spread Bactériosol on my fields. When neighbours ask me what I am doing, I tell them: “No, I am not spreading fertilisers, I am sowing micro-organisms”. They are surprised because they don’t know about it and I take the time to explain it to them.


A farmer takes on himself all of society’s troubles. Telling ourselves that we are not part of it is really important. There are more people fighting us than helping us, this is why we need to be strong. I have talked with the technicians from the Coop or from the Chamber of Agriculture but I am not rushing into things. Many are doubtful. We cannot revolutionise agriculture in one day. If we go too fast, we can be sure to fail. We have to prepare the ground and let people know we are here. This is my strategy! (Laugh) Well, they look at us and listen to us, they are forced to admit that we are doing as well as they are.

I have been working that way for 13 years now, and one cannot doubt my credibility. I have noticed that in front of professionals who are willing to involve themselves in the process, my words are worth a lot. I am glad to help moving things forward.

If I had to summarize this adventure, I would say that I have come back to forgotten values. Soil is the base of everything and a healthy soil is a guarantee of good life to come; healthy animals as well as balanced humans. We are getting back to values our ancestors use to have: patience and common sense

In the current context, autonomy is crucial. I have always been independent with forage but now I have reoriented my production a little. I have reduced my corn surface by 20%, and I have increased my production of grass with some blends, leguminous plants and hair grass; thus, more autonomy in terms of nitrogen. This year, I ensilaged grass for the first time, and I saw the difference. I need half the nitrogen I used to need, with only a third of ensilage in the ration.


It is true that because I need less and less chemicals and nitrogen, this system is economically worth it


 It is a new way of working. Spring is a key season; We have to learn many things again and I have discovered even more this year with the dry spring we suffered. We collected a first cut of grass really early because it had grown fast. The second cut (mid-July) has not been done yet. I have learned to be patient. You have to let the leguminous plants reach their maturity level before thinking about cutting. In the coming years, I am going to start mixing crop of wheat and rye instead of corn. I can still improve a lot.

In relation to the French “Grenelle de l’Environnement”, I am sure about one thing, i will not be behind. 25 years ago, we were not talking about environmental issues like we are today. It is true that we have made many mistakes but those mistakes were encouraged and sometimes forced on us. Now I feel I have my fate in hands, I have come a long way.



Mr Gruel uses Bacteriosol to fertilize cereals and meadows and Bacteriolit to enhance the value of ma­nure.


  • Rapid development of manure.
  • Almost a total disappearance of the smell.
  • Improvement of the atmosphere in livestock buildings.
  • No more diarrhea when the cows are out in the meadows.
  • Lower veterinary fees (From 150€ to 40€ per cow).
  • Better animal digestion and fewer limps.
  • Suppleness of the land more assertive.
  • An incredible repopulation of the soil.
  • More autonomy
  • This system is economically worth it.