Story highlights There's a new documentary on Japanese farmers keeping radiation-affected cows alive

Why are the farmers keeping them alive? Love

(CNN) Some families have at least one relative who's either odd or eccentric. Others boast family members of a more unusual kind.

That's what one filmmaker discovered in 2011 when he heard of a group of former farmers in Fukushima 's nuclear exclusion zone, fighting to keep their radiation-affected cows alive, though they brought them no profit.

"The farmers think of these cows as family. They know that these cows can't be sold, but they don't want to kill them just because they're not worth anything," Tamotsu Matsubara, who made a film called 'Nuclear Cattle' (Hibaku Ushi) on their plight, told CNN.

It costs around 2,000 dollars to maintain each cow for a year. The farmers featured in Matsubara's film are among those who refused to obey the Japanese government's initial requests to euthanize cows in the exclusion zone.

"[These farmers] really want them to serve a greater purpose for humans and for science," explained Matsubara.

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