The racing incidents from Race 4 on 2017/12/13 at Mysore states

"Trainer Mr. Faraz Arshad was fined Rs.10,000/- by the Stewards for accepting his charge GAME AGAIN (Ryan Marshall), in the above Race, without a valid Coggins Test Certificate, negative for EIA; Subsequently it was permitted to be withdrawn from the above Race."

Could trainer/assistant or official shed light into why this test was requested in the first place? Under what circumstances is this test requested or is it common protocol for every horse?

What are any other such tests that are requested from trainers?

(Coggins test is a diagnostic test performed in horses to test for Equine infectious anemia or swamp fever)