The malnourished wild child, dubbed Sasha T, had been kept alongside the animals by his mother.
Sources said he played and slept with the goats and had not learned to speak, eat, or use a potty.
Irina Bochkova, deputy head of social work in Shakhti, in Russia’s Rostov region, said: “When we came in, Sasha was sitting in the ice-cold room, undressed. His mum was absent.
“Every hour could have become his last. It was incredibly cold, dirty and smelly in that house. We just grabbed him and rushed him to the city hospital. Doctors said that, because of how he lived, his brain has not developed properly.”
The boy weighs a third less than a typical child of his age. Children’s doctor Natalya Simonina said: “He refused to sleep in the cot. He tried to get under it and sleep there. He was very scared of adults.
“He tried to break everything he saw — windows, furniture. He could not speak or hold a spoon. He had no idea about what to do with toys.” The boy’s 40-year-old mum is set to lose her maternal rights.