Tail shortening or docking causes pain and makes a cow less effective at swatting flies away. There are also myths that tail shortening reduces milker exposure to Leptospirosis, reduces mastitis and somatic cell count, and improves udder hygiene. Good hygiene, stockmanship, and vaccination programs are more effective.

What tail shortening does:

• Causes pain
• Makes a cow's fly swatter ineffective

What it doesn't do:

• Reduce leptospirosis or other zoonoses
• Reduce mastitis or SCC

Switch trimming

Tail switch trimming can improve udder health and keep cows’ udders and milkers’ faces clean, while still allowing cows to deter flies.

Switches can be trimmed using hand shears, scissors, or electric trimmers. Many farmers trim cow’s tails after they calve or as they leave the colostrum herd, providing a useful indicator of what cow is meant to be in what mob in case they get mixed up.

A small percentage of cows have persistently dirty tails all season and will require regular trimming. 

Precautions to minimise spread of zoonoses should be taken even if tails are trimmed, including vaccinating the herd for leptospirosis, regular hand washing, keeping wounds covered, and using PPE.