A police official informed that cows were fed with expired flour by a local trader.
On Wednesday, most cows fell ill and five among them were died the same day.
Though veterinary doctors jumped into action, another 12 cows died on Thursday.
Veterinary doctors claimed that it was a case of food poisoning.
Based on information received from the cow shelter's management, the police filed a case against Samba Siva Rao, the proprietor of Bhavani Traders.
Water Resources Minister D Umamaheswara Rao also visited the cow shelter and asked the veterinary department to take care of the remaining cows.
Devotees who used to visit the cow shelter protested and demanded action against the supplier of flour.