Which food should not be given to a cow?

I am living in Gandhinagar, Gujarat, India. Indian culture has accepted cows as mother, because it feeds milk to us. Hindu culture says whoever feeds you is mother to us. Cows are a precious animal and there are many tales and stories behind cows in Hindu culture.

In Hindu culture, especially in villages, there are people called “Bharavad” or “Gvala” whose main pet is a cow.

I have one friend who is from this community and is living near my house only.

I’ve learned from him about what food is bad for cows. According to my conversation with him, I found that following food are banned to feed to a cow.

1. Aaata or “Lot”

   To make Indian Chapatis / Indian breads we make “aata”, this food if a cow eats it, it sticks in the cow’s neck, so it is banned. So this food is banned to feed to cows.

2. Poly thin / Plastic bags

   Of course, no description needed.

3. Plain wheat or Plain Rice

   Whenever we cook rice, the rice size increases, So if a cow eats rice, the cow’s stomach size increases and the cow dies.

So far I’ve found only these 3 foods, which also was not taken from any doctor or professional.

So I am interested in knowing which food should not be given to cow as per a doctor or professional. This is very important because cows are very important for us.

Any Help is appreciated, Thank You in advance.