There is a well known park selling animals in Mauritius. People do buy their Qourbani animal from there as well.

Question

There is a well known park selling animals in Mauritius. People do buy their Qourbani animal from there as well. However the Qourbani animal is sold by weight like other animals throughout the year. Meaning that there is no concern from the seller’s side about the animal being in the right age for Qourbani. And the buyers do not have any other option where they can identify the age as well. The sellers know well that the big animals like cows have to be 2 years of age, still they are selling under age. Now who will be responsible if under-age animal was used for Qourbani?