The Scourge of Calf Scour

Did you know that 50% of calf deaths are caused by Scour?

Scour is a costly problem. It causes deceased live weight gain, leading to the heifer being older at its first serving/calving. Profitability is delayed and cows older than 28 months at the first calving can have problems calving.

The calves that suffer from scour are more susceptible to a range of other diseases and sick calves lead to increased veterinary bills and labour costs, not to mention the effect it has on a farm's morale.

What causes it?

• Poor intake of colostrum

• Stress from the environment

• Suboptimal hygiene

• Other diseases

• A build-up of harmful micro-organisms throughout the calving period

What happens to the calf when it has scour?

Dehydration, electrolyte loss and gut damage are features of calf scour. Dehydration causes decreased tissue perfusion and kidney activity, which can even lead to death. Electrolyte loss can affect the blood's pH balance, causing acidosis. When experienced together, dehydration and electrolyte loss can result in death if the correct treatment is not given. Damaged gut villi caused by scour can negatively impact the calf's growth rate through it's lifetime.

What does the calf need to make it better?

You want the treatment for scour to rehydrate the calf and correct acidosis and also to replace electrolytes. Teagasc advises proper calf recovery needs correction of acidosis. EU regulation No. 1123/2014 requires all scour treatments to have a Strong Ion Difference (SID) of at least 60mmol/litre, making sure that blood pH and base excess are restored with 12-18 hours, thus helping calves to get better fully.

Why is milk clotting important?

Milk needs to clot in the calf's stomach to allow for digestion of protein. If milk does not clot, it quickly moves through the stomach, which means a missed opportunity for protein digestion.

Solutions with bicarbonate and citrate shouldn't be added to milk because this can affect milk clotting. Glucose can also affect milk clotting and make diarrhea worse through the osmotic effect. Since the calf needs energy, large amounts of glucose are needed however, exercise caution when choosing a therapy with high amounts of glucose to treat scour as it may make the problem worse.

Should the calf be kept on milk?

Research shows that keeping a calf on milk is beneficial as milk has 50g/l of lactose (energy), which assists weight gain. Milk also has immunoglobulins and helps repair the gut. The milk has other benefits for the calf; it is antimicrobial, palatable and maintains the correct abomasal pH. Suckling eliminates the stress caused by separating the calf from its mother in suckler herds.