Respiratory diseases, along with diarrhea, are the most common diseases in calves from about 3 weeks to 9 months of age. Visible signs of respiratory diseases include a body temperature above 39.5°C, nasal discharge, dry cough, and decreased appetite. Respiratory diseases have a strong impact on growth and later productivity. Early detection and treatment are therefore extremely important to avoid animals with chronic lung damage. Our Calf Monitoring System can help you with early detection and treatment with its novel sensor technology.
Risk factors for respiratory diseases are insufficient immune transmission from colostrum, long contact with older animals, but also limited ventilation, as it is often the case in warm barns. However, severe temperature fluctuations, transport or stress, can also contribute to the development of this disease.
Pathogens that cause the disease include both viruses and bacteria, and usually more than one pathogen at the same time is responsible for the calf’s illness. However, the treatment of bacteria should be priority as they determine the severity of the disease. It is also common for calves that are housed together, to be affected at the same time.
But what does this mean for the farms?
As with other diseases, it is important to first optimize the colostrum strategy. This gives the foundation for optimal calf immunity. For this purpose, it is crucial to milk the cow quickly after birth, for that the calf can drink three liters of colostrum within the first four hours of life and a total of four liters within the first 12 hours of life. In addition, the colostrum should be tested to ensure a high quality (at least 22 Brix). For more information on colostrum, see our article.
In addition to the optimal colostrum supply, it is particularly important to take a closer look at the housing conditions of the calves. The biggest risk factors are shared air space with older animals, overcrowding, high-pressure cleaning in the presence of the animals and stress in general.
But housings that are too warm or have harmful substances in the air, such as ammonia, dust and mold, can also irritate the respiratory tract. Ammonia concentration is significantly influenced by adequate ventilation, provision of dry bedding, and regular manure removal.
When choosing the type of housing, it is important to keep in mind that calves are born with a functioning thermoregulatory system. This means that they can cope with different ambient temperatures if enough energy is provided, and the housing is draught-free, dry and well littered. To ensure adequate ventilation, four air changes per hour should be achieved in winter and up to 40 in summer.
Housings with outdoor climate conditions are advantageous, as elevated levels of noxious gases can be avoided. In particular, outdoor calf pens have a positive effect in preventing diarrhea and respiratory diseases. Regardless of the type of housing chosen, emphasis should be placed on plenty of dry bedding, as this can prevent the occurrence of respiratory diseases. This is especially important in colder months to prevent the calves from cooling down due to heat loss.
As a guideline for the amount of bedding, there is the Nesting Score. A score of 1 means the legs are completely visible when laying down. 2 means the joints are partially visible when laying down. A score of 3 means the calf can completely bury itself in the straw and the legs are completely hidden. This amount of bedding is targeted to provide the calf with optimal protection from chilling. The strong effect of too little bedding (nesting score 1) on the occurrence of respiratory diseases is visible in Figure 1.
In addition to housing conditions, stress management also plays a major role in preventing the occurrence of respiratory diseases. Whenever changes are in store for the young calf, it should be kept in mind that stress is also a major risk factor for calves. Therefore, care should be taken to avoid, if possible, multiple stress factors such as transport, loss of familiar surroundings, integration into a new group or feed change at the same time. For example, it is advisable to accustom the calf slowly to the new feed ration before it is transferred to a new group where the new ration will be fed.
If a farm buys animals on a regular basis, an extra quarantine pen should be set up. It is also advisable to have a screening performed by the farm veterinarian to detect any pre-existing lung problems. In addition, it is advisable to carry out daily temperature checks during the first two to three weeks after stabling, in order to be informed quickly about incipient diseases and to be able to act fast.
In summary, it can be said that outdoor pens are the optimal housing form to prevent respiratory diseases, due to the good climate. When setting up the pens, care should be taken to ensure that the opening faces away from the weather, protection from strong sunlight is possible in summer, and that a firm base is available. The paved underground is particularly important, as both the pen and the floor plate should be cleaned and disinfected with a steam jet before each new calf.
Our expert tips in the checklist:
Optimize colostrum supply
- 3 liters in first 4 hours, total 4 liters in first 12 hours
- Tested quality (optimal >22% Brix)
Optimize housing conditions
- Outdoor climate housing, if possible, preferably igloos
- Winter: four air changes/hour; summer up to 40/hour
If, despite good management, an outbreak of respiratory disease occurs, our Calf Monitoring System can help you detect them early and give you initial recommendations on what steps to take in this case. We will be happy to explain the advantages this has for you in a personal consultation.