Caused by a change in milk composition, amount fed or milk temperature.
The scours are often white and pasty. The calf is happy, feeding well and well in itself.
It is impossible to predict or identify the cause of scours without testing!
most common cause of scours in calves. Most common in calves between 3 and 8 weeks of age but may occur earlier. Usually mild yellow scour by itself but can be severe and very watery. Often causes death especially in combination with other causes. Other viruses (e.g. Coronavirus) present similar to Rotavirus.
Uncommon as a primary cause but very severe on top of other causes.
- E.coli: Can cause rapid death (less than 12 hours) in calves less than 7 days old
- Salmonella: Acute and often fatal
Treatment and Prevention
1. Individual Treatment
Cryptosporidia: Common cause in calves one or two weeks of age or older. Organisms spread for a month or more in faeces. Contamination! Commonly in combination with Rotovirus, where it causes severe diarrhea and may be fatal. There is no registered treatment for Cryptosporidia.
Coccidia: Scours in slightly older calves (from 2-3 weeks up to 9 months). It commonly presents as scours with blood tinges and the animal straining to defecate.
- Replace lost fluid, electrolyte and energy levels with a good quality electrolyte such as Revive or Diarrest. These mixes are made up to 2 litres and fed 2-3 times daily for up to three days (see protocol below).
- Use a tube feeder for any slow or weak drinkers.
- Scouring calves should be isolated and kept in a warm clean environment and stress free. Use an absorbent surface such as wood shavings as a floor covering and top up daily.
- Gut protectants e.g. Kaolin, Pectin can be of some use in inflamed guts. These are often in a mixture with sulpha drugs (scourban).
- Benonite clay (Trubond / Ruminite) absorbs water and slows the passage of feed through the gut. They have the advantage of no withholding period unlike products containing sulpha antibiotics.
- Antibiotics are only occasionally an important part of treatment and are often only recommended in Salmonella cases.
- Veterinarian attention should be sought for any calf, which is weak, cold in the ears and limbs or unable to stand. These usually need intravenous fluids to save them.
- Bobby calves must not be given an antibacterial at any time!
2. Whole Mob Treatment
||Leave 3L electrolyte in feeder overnight
- All scouring animals should be moved to a ‘sick pen’ where management aims to reduce the number of organisms in the environment and stop transmission to uninfected animals be keeping infected calves separated until they have recovered. Physically separate groups by at least 2 meters and preferably house in separate buildings.
- Pens should be cleaned out daily removing all faecal matter in order to reduce the number of infective organisms ingested.
- Spray the pens, equipment and environment with virucidal spray daily.
- Top up the floor surface, shavings etc daily.
- Ensure your hands, gumboots, equipment etc are well cleaned and disinfected before leaving this area.
- Also, these calves should be fed last and equipment (e.g. food bins) should not be used for uninfected calves thereby reducing transmission of organisms.
4. Good Hygiene
- Ensure good calf rearing principles.
- Maternal antibodies are absorbed from colostrum by the calf through ‘pores’ in the intestine. The calf starts to lose this ability after only a few hours of life and there is some evidence that colostrum itself starts the closure of these pores. Ensure every calf gets at least 2L of colostrum in its first 6 hours of life. (Optimal is 10-15% of body weight) and at least 4L in the first 12 hours.
- Spray navels with iodine after birth daily for 3 days and ensure good hygiene on tray/trailer when calves are picked up and good colostrum intake.
- Ensure calves are kept in groups of similar age and size and in a group of no more than 20 animals. Ideal groups are: 0-7 days; 1-4 weeks; older than 4 weeks. Ensure these groups remain closed once formed.
- Minimize stress and chilling during sale and transport.
- After significant transport feed electrolytes for the first 12 hours.
- House in a dry, draft free, hygienic shed.
- Avoid sudden changes in the type, quantity or temperature of milk.
5. Rotavec Vaccination
- Clean pens regularly with a virucidal spray.
- Regularly clean any feeding and other equipment.
- Isolate any calves brought onto the farm for at least 5 days.
- Ensure pens are well drained and kept dry.
- Pens should be emptied out and disinfected between mobs and at the end of the season clean out all calf rearing facilities with the strongest products e.g. Farmsan RTU.
Where there is a serious and ongoing problem, especially where Rotovirus is an ongoing problem, vaccination with Rotavec should be considered. Modern vaccines make this much simpler with only a single injection necessary, which is given to the dam between 12 and 4 weeks prior to calving. This gives protection against Rotavirus and E.coli, through the colostrum to the calves. Vaccination will markedly reduce the severity of mixed infections especially Rotavirus / Cryptosporidium infections but depends on getting good quantities of colostrum into the calves in the first few hours of life.
This is mostly used in the treatment and prevention of viral scours and contains antibodies mainly against Rotavirus. Combinations are also available for Coronavirus, Salmonella and Cryptosporidium. Rotagen is administered to the calves in their milk without the need for electrolytes, and has been found to be useful in the face of infection.