During calf rearing, it is of course important to keep disease levels as low as possible at the farm, thus ensuring as robust as possible animal health. Diarrhoea is one of the most common conditions in young calves. Research shows that a calf with diarrhoea has a 17 times greater chance of respiratory problems, and that the risk of compelled removal of the dairy cow in the first lactation is 2.5 times as high (Antonis et al. 2017). This has significant financial consequences for dairy farmers. Furthermore, German research suggests that an outbreak of diarrhoea costs between € 75 and € 145 (Lührmann 2009). This includes the cost of medicines, electrolytic drinks and veterinary visits.
But the growth delay caused by diarrhoea also costs money. Lower growth often means a later moment of insemination and calving and lower milk production when the heifer enters lactation. Research shows that in 1 case of a diarrhoea outbreak in a heifer calf results in that calf not growing for 1 week. The estimated future yield loss is another € 75 per calf. So a diarrhoea outbreak in a heifer calf costs an average of € 150 per calf.
Diarrhoea can have different causes. Specifically bacteria, viruses and parasites can cause digestive disorders and have an enormous impact on animal health. The figure below presents the key causes, including the period in which the different types of diarrhoea occur most (Rumivar studiemiddag kalveropfok 2017).
In almost all cases, the calf loses a lot of fluid, bodily salts and energy. Within 1 day, a calf can lose up to ten percent of its body weight in fluids (Kehoe & Heinrichs, 2005). Furthermore, there is a greater chance that the calf acidifies – the pH value of the blood falls – as it loses a lot of alkalinity. The intestinal wall may also be damaged and a number of diarrhoea-causing pathogens produce toxins. This all results in the calf dehydrating, losing weight and suffering growth retardation. In the case of severe diarrhoea, the calf may even die. It is therefore extremely important to treat diarrhoea in calves quickly and adequately. This means that the calf must receive sufficient fluids, energy and bodily salts (electrolytes) as soon as possible. It is also important to stem the diarrhoea and where possible protect the intestinal wall. This can be done by feeding the calf products like pectins and tannins. It is of course also essential to ascertain the cause of the diarrhoea to prevent further spread or repetition of the disease.
It is a well-known problem: iron deficiencies in calves. The cause of this is often that the calf is born with low iron reserves and the cow’s milk contains insufficient iron to compensate for this shortage. An iron deficiency can cause anaemia. This is because iron plays a major role in the formation of haemoglobin. Haemoglobin is a protein that binds oxygen and then transports it through the system. A deficiency of iron therefore means that not enough haemoglobin is created and too little oxygen finds its way through the body. And the result of that is lower vitality of the calf, lower feed intake and growth and a dull hide.