E coli Diarrhoea

E.coli is a bactrium present in the gut of normal animals. Three types are associated with diarrhoea in calves; ETEC, EPEC, EHEC.

How is the disease transmitted and spread?

The three bacteria act on different parts of the intestine:

ETEC attaches and casues damage to the small intestine; it produces a toxin known as enterotoxin.

EPEC also attaches to and damages the small intestine but does not produce enterotoxin.

EHEC attaches and causes damage to the large intestine.

The disease is spread through contact with faeces.

What are the clinical signs of the disease?

ETEC

•  affects young calves less than 3 days old
• very watery diarrhoea
• calves become depressed and don't drink

EPEC

• usually affects calves under 21 days old
• diarrhoea is watery and yellow
• not as rapid and severe as ETEC

EHEC

• usually affects calves around 14 days
• diarrhoea is often bloody

Prevention and control of the disease

• The environment should be kept as clean as possible, particularly the calving yards and pens.
• Single penning of young calves will help to reduce the spread of the disease. As sick calves will pass on a huge number of bacteria, disinfection is essential.
• An all-in-all-out system will allow pens to be fully disinfected between batches and will prevent the disease being passed to new arrivals.
• Good colostrum intake increases the calves' immunity. In infected herds feeding bulked colostrum for 7 days can reduce the number of cases.
• A vaccination is available for ETEC. This is given to the mother in late pregnancy resulting in the antibodies being present in the colostrum. For best results colostrum feeding should continue for at least a week.

Source: NADIS