The colourwork was inspired by a mass produced vest as in last photograph.
I used a basic cardigan pattern (linked above) and inserted my version of the highland cows and fairisle style stranded colourwork to the pattern. Each section of the fairisle has two rows/rounds of purely background colour in-between.
Welt and cuffs have 16 rows/rounds of ribbing.
The body was worked in one piece to the split for sleeves.
Shoulders are joined with kitchener stitch.
Sleeves are worked seamlessly in the round.
6 buttonholes as that worked better for the ribbing.

Overall weight Inc buttons is 133grams.
Also used a few yards of some old off white baby yarn for the horns, noses, legs. As it was a thicker DK I removed one of the plies to make it thinner. It was still a bulkier yarn than the Sirdar 4ply but has given an extra bit of character to the cows faces.