Hjjtoleslam Rahmati said in interview with ISNA "Indeed all Islamic decrees follow expediencies and vices. The same is true of ritual slaughtering, that is, if we slaughter animals according to the rituals we will gain benefits from the meat we use and if we do not do that and oppose the decree, surely malignancies are directed at us.”
He added "A while ago I read a research by a Muslim lady at a US university. They had noticed that if an animal is ritually slaughtered, the amount of blood that comes out of its body and circumstances of the slaughtering remove the grounds for many diseases. But if it is slaughtered in a way other than the ritual way then conditions will exist in the meat for a lot of diseases.