There is a big misunderstanding between breeder and owner.
The breeder is the one that bred, that actually has their brand on the horses; it signifies how many babies with your brand have been born in your breeding program/history.
The owner is the one who owns but not necessarily bred those horses. This means how many horses in the herd no matter which brand they have.
As far as I know, the largest owner is a Mexican gentleman. I don´t remember his name now, but he also has cross-breeds.
Until 2011, we were the largest breeder and owner of Pure Lusitanos with a herd of 1100 horses registered at the Association. In 2011 we started reducing the herd and today we have 442 horses here of all ages, all pure. However, these numbers do not match official Stud Book records as the records are not up to date (horses in the process of ownership transfer, horses that passed away, etc. so the Stud Book number is bigger)
Interagro has bred, since 1974 in Brazil, officially 2193 pure Lusitano colts and fillies, i.e. we had 2193 babies born here at our facilities with our brand. Officially, because at that time you had 90 days to register a newborn and those who unfortunately died before this age were not registered.
Unfortunately, the Lusitano Association Stud Book is not updated, that´s why I am giving you the real numbers here. If you consult them, there will be more (because of ownership and death communications still being processed).
Thank you for giving us the opportunity to clarify this matter as we see a lot of adverts of new breeders calling themselves “largest breeder” when they recently bought dozens of mares of other breeders and believe that owner and breeder is the same thing! And we proudly have our 34 year-old mares here; our group of retired ladies are hard to find at any other Stud Farm nowadays.
We consulted the official Stud Books to check if they knew of any other breeder who had more than 2193 horses born with their brand and they said no. So, as far as I know, Interagro is still the largest breeder in the world, but not the largest owner!