Johanna Marsden BVSc MRCVS, Molecare Farm Vets
Calf rearing is a key stage in beef production that will determine the quality of the finished animal. Brought in animals face higher morbidity rates than home bred stock, and so choosing calves from the right farms is essential alongside good calf management.
To minimise the risk and spread of disease, each batch of calves should be brought directly from the same producer with a history of good colostrum management and a disease-free status. However, this is not always possible, with most calves coming from a mix of farms through market. Therefore, it is important to know the risks of buying in and how to reduce occurrence of disease in order to run a profitable enterprise and maintain a healthy herd.
When calves are going through market or travelling long distances they will be stressed and therefore more susceptible to respiratory diseases and scours. In order to minimise the stress during this period, housing should be ready for when they arrive at their destination, with adequate space and ventilation, as well as clean bedding and water. During transportation calves can also become dehydrated and often lose weight. To help reduce the effects of this we would recommend that you provide ad lib warm electrolyte solution 2-3 hours after arrival on farm. On day 2 we would also advise that you feed a milk replacer in the morning, a 2L electrolyte solution at midday and then a milk feed in the evening. It is important to have forage available and introduce concentrate from day 1, increasing to adlib concentrate on day 3.
To prevent disease from coming on to your farm, it is important that you follow a quarantine protocol and keep the calves in a separate area to other animals for at least one week. On arrival to farm, we would advise that you assess animals for lameness or any injury during transport. This should then be followed, by taking their rectal temperature two hours later, with any animals displaying over 39.5⁰C moved to be isolated, assessed and treated as necessary. From day 2 you can begin your vaccine protocols. This gives the calves time to settle, enabling the vaccines to give better protection after administration. If calves are coming from a known source it would be beneficial for the respiratory vaccines to be started before they travel, as this will give them protection during the stressful period.
Buying in any animals always brings a high risk of introducing new diseases to your farm, for example Bovine Viral Diarrhoea (BVD) or Mycoplasma. During the quarantine period the calves should be monitored for any developing signs of illness to decrease chance of these and other diseases spreading to the rest of the livestock. Look out for clinical signs such as scours, respiratory disease, head tilt and lameness. It is important to speak to your farm vet should you see any symptoms in your animals.
BVD is a viral disease that causes reproductive losses and an increased incidence of other diseases in cattle. Animals infected as adults will recover and become immune, however if they become infected during pregnancy, they may give birth to a Persistently Infected (PI) calf. A PI will continue to shed the virus, lowering the immune system of other calves it is in contact with as well as infecting any naive adult cattle. To ensure you do not buy in a PI animal you should only buy from farms that are BVD Free, or where the calves have been tested for the virus with a Tag and Test. This test can also be done when the calf arrives; an ear tag sample is sent off from each calf to test if they are a PI, and any that come back positive should be removed from the farm.
Mycoplasma is a bacterium that effects calves mainly by causing pneumonia and is considered high risk from brought in stock. It can also affect the inner ear of calves, causing a head tilt and cause joint pain. It is very difficult to treat and currently there are no vaccines available in the UK.
If you would like more information on quarantine protocols, or if would like advice on how to prevent respiratory disease from entering your farm, please speak to your Molecare Farm Vet, or contact the office on [email protected] or 01392 872394.