Back to basics: Preventing and treating calf scour

Neonatal calf scour is one of the most common illnesses seen in young calves. Year-on-year, it continues to be the most frequently diagnosed cause of death in calves up to one month of age in the Regional Veterinary Labs; it accounts for 28% of diagnosed conditions in this age group.

The economic losses of calf scour incurred on-farm can be substantial due to calf mortality, treatment costs, weight loss and subsequent poor growth rates.

Prevention

The single most important “weapon” that farmers have in the prevention of calf scour is to put an effective colostrum management programme in place.

Colostrum – the first milk a cow produces after calving – contains vital immunoglobulins that help to prevent infectious disease in the calf. Calves are born without any immunity, as no antibodies can cross the placenta. Therefore, they rely solely on the passive transfer of antibodies from colostrum.

Each and every calf should receive 3L of colostrum as soon as possible after birth – ideally within two hours. After this, the calf’s ability to absorb the disease-preventing immunoglobulins/antibodies diminishes. When the calf is 24 hours old, its ability to absorb antibodies has diminished completely.

Treatment

Unfortunately, calf scour – even under strict management practices – still occurs. When it does, a net loss of fluids occurs in the animal. The calf is losing more fluids than it is receiving from the diet.

This quickly leads to a dull, depressed and dehydrated animal.

A number of steps should be taken once the scouring calf is noticed:
  • Step 1: Separate the calf from the group to help stop the spread of disease;
  • Step 2: Administer oral rehydration therapy (ORT);
  • Step 3: Continue to feed milk.

ORT is the single most important therapeutic measure to be carried out to help correct the dehydration, acidosis and electrolyte imbalance that occurs in scouring calves.

It is usually successful if instigated immediately after scouring has developed. 4L of electrolyte solutions should be provided to scouring calves in addition to normal milk feeds.

Traditionally, calf scour treatments have involved the administration of oral fluids along with the withdrawal of milk. However, current recommendations insist that scouring calves should be fed milk in conjunction with an oral rehydration solution.

Dairy calves should be fed milk as normal, along with supplemental feeds of electrolyte solutions. Beef calves should remain with their mothers. The withdrawal of milk is contraindicated, as it results in malnourishment and weight loss in vulnerable calves that have poorly-developed fat stores.

Continued milk feeding not only provides the energy required for weight gain and growth throughout the period of diarrhoea, but also provides the nutrients that are necessary for the recovery of the intestinal mucosa.

Considering the natural antimicrobial properties of fresh milk (e.g. lactoferrin, lactoperoxydase, lysozyme, etc.) and its great digestibility, milk is actually the ideal nutrient to support a scouring calf.

Continued feeding of milk to diarrhoeic calves with oral rehydration therapy has beneficial effects on weight gain, physical appearance and recovery rate. In addition, studies show that scouring calves that remain on milk have the same weight gain as healthy calves. Click here for more information