Calf Scours: Rapid Kits and RT-PCR Panels

Calf scours is diarrhoea in young calves, and the danger is dehydration. A rapid kit on fresh dung can point to rotavirus, coronavirus, cryptosporidium or E. coli K99, and an RT-PCR panel can search more widely. A scouring calf needs a vet quickly; the tests help to find the cause and to protect the other calves.

Why do calves get scours?

A young calf has an immature gut and an immune system that depends on first milk. Several germs can cause scours: the viruses rotavirus and coronavirus, the parasite Cryptosporidium, the bacteria E. coli K99 and Salmonella, and coccidia. Poor hygiene, crowding, cold wet bedding, and too little first milk make an outbreak more likely. Feeding errors can cause scours as well.

The calf loses water and salts in the dung faster than it can drink. Sunken eyes, a dry mouth, cold ears, weakness and refusal to suckle are signs that it is becoming dehydrated. A calf that cannot stand needs a vet at once. Do not wait for a lab result before getting help. Good nursing starts with the vet, who decides what the calf needs. While you wait, keep the calf warm and dry and apart from the others, and note how many calves are affected, how old they are and what they were fed. Do not give medicines meant for adults or for other species. If one calf is sick, watch the others every day for the first signs, such as a dull look, a slow suckle or soft dung, and tell the vet early.

What does a rapid kit show?

The Calf Diarrhoea Rapid Test (Rotavirus, Coronavirus, Cryptosporidium & E. coli K99) is a kit that looks for four common causes in a sample of fresh dung and gives a first answer quickly. It is useful for deciding which germ is likely in a herd with several sick calves. A negative kit does not mean there is no infection, because the germ may be too few, and the kit does not cover every possible cause.

When is an RT-PCR panel used?

The Calf Diarrhoea RT-PCR Panel is an RT-PCR (real-time PCR) test that typically looks for several of the main causes of calf scours in one sample, and the exact list is confirmed when you book. RT-PCR looks for the genetic material of the germs, so it can find them even in small amounts. The Cryptosporidium RT-PCR looks for Cryptosporidium alone. Vets use the panels when the kit is negative, when scours keeps coming back or when several calves are affected.

What should you remember about people?

Cryptosporidium and Salmonella can pass from calves to people, especially children. Wash hands with soap after handling calves, their feed and their bedding, and do not let children play in the calf pen. If a family member has diarrhoea after handling sick calves, they should see a doctor.

How do you collect the sample?

Take fresh dung from the scouring calf, ideally before any medicine is given, because treatment can make the test miss the germ. Use a clean, lidded container and a spoon that has not been used for anything else, wearing gloves. Label it with the calf's number and the date, and keep it cool. Sampling several sick calves gives a better picture of the herd than sampling one.

What helps prevent outbreaks?

The most important step is that every calf gets enough good first milk soon after birth. A blood test can show whether it did, and the Calf Health Check Pack groups that with worm and coccidia checks. Clean, dry bedding, clean feeding equipment and keeping sick calves apart all help. Your vet can advise on what suits your farm, and the lab gives no treatment advice.

Read next

For worms and coccidia in buffalo calves, read Buffalo Calf Diarrhoea and Worm Tests. To plan checks through the year, see Dairy Farms Around Bhopal: A Yearly Herd Testing Calendar.

Testing in Bhopal

Your vet usually takes the sample, and the lab at C-200, C Sector, Shahpura, Bhopal accepts it. Collection is free anywhere in Bhopal, and other districts can use courier, bus parcel or their vet. Call or WhatsApp +91 88175 01118; the lab confirms the method, sample needs and reporting time when you book. A registered veterinarian reads the results with the calf's signs.