A cow that stops eating or drinking is sick until proven otherwise. Loss of appetite is one of the earliest signs of illness in cattle, and some causes can be fatal within hours or days. Call your vet the same day, and right away if the cow is down, bloated, breathing hard, or has not eaten for more than a day.
Common causes
- Milk fever (low blood calcium): around calving, especially in dairy cows. Signs include weakness, shivering, an unsteady walk, and lying down. It needs urgent veterinary treatment.
- Ketosis: in early lactation, when the cow cannot eat enough to meet energy needs. Signs include poor appetite, weight loss, and a sweet smell on the breath.
- Rumen problems: acidosis from too much grain, or bloat, with a swollen left side.
- Displaced abomasum: a “ping” sound on the left or right side, reduced manure, and falling milk.
- Hardware disease: a swallowed piece of metal that damages the stomach lining, causing pain, arched back, and reluctance to move.
- Infections: mastitis, metritis after calving, pneumonia, or foot problems. A fever is a clue.
- Heat stress, stress, or poor water access: hot weather, frozen or dirty troughs, or moves and herd changes can cut intake.
- Bad feed: moldy hay or silage, sudden diet changes, or toxic plants.
What to check right now
- Is the cow standing? A cow that is down needs a vet immediately.
- Look at her left side for bloating, and check her breathing and manure.
- Take her temperature. A normal adult cow runs about 100.4 to 102.5°F.
- Check the water supply is working, clean, and not frozen.
- Check the feed for mold or recent changes, and look for chewed wires or other hazards.
- Look at her udder for heat, swelling, or changes in the milk.
Call the vet right away if
- The cow is down or cannot rise.
- Her belly is swollen or she is breathing with difficulty.
- She has a high fever, stops chewing her cud, or has not produced manure.
- She recently calved, or is close to calving.
What not to do
Do not force fluids or drench a cow that is down or cannot swallow properly. Liquid can go into the lungs. Do not give medicines, calcium, or drugs without veterinary advice, since dosing and route matter. A vet will give the right treatment, and following their instructions on rehydration and diet is safer than guessing.
Prevention
- Make diet changes gradually.
- Keep clean, accessible water in every pen and pasture.
- Balance calcium, phosphorus, and minerals for dry and fresh cows with your vet or nutritionist.
- Remove spoiled feed and check fences and feeders for metal hazards.
Related guides
Bottom Line
A cow that refuses food or water needs prompt attention. Check the basics, then call your vet instead of waiting. This page is general information and not a substitute for veterinary care.
