It is not quite as simple as that, since rods in the retina produce an image right across the visual spectrum and it is then down to the cones to colour the image. On the R O Y G B I V spectrum, starting at Y and going to B, Assuming that bovine vision covers the spectrum, everything will move along, leaving blood as yellow and the grass as a dirty brown colour. If however Y started as yellow, red and orange would appear in monochrome. Unless we connect a cows eyes to a human brain, no one will ever know the REAL answer to how the luminance and chrominance work together.
I will have to think on that when sober. Did you miss my important link??? This is an interesting article I read a while back. How do Namibian Himbas see colour?