Born and bred for a healthy future
To ensure calves are in top condition, minimise exposure to disease and defend against it
Published 23/02/2010 | 05:00
Management and environment
To ensure a healthy calf, the aim is to minimise the calf's exposure to disease, and maximise its defence against disease. In minimising a calf's exposure to disease, providing a clean, disease-free environment is fundamental. This involves:
- Thorough cleaning and disinfection, before and during the calving season, of all areas used by calves.
- Providing a clean, straw-bedded lying area with no draughts and good ventilation.
- Accommodating cows and calves in batches based on order of calving so that young calves are never mixed with or accommodated in areas used by older calves.
- Avoiding introduction of disease from sources such as purchased calves. Isolate all purchased animals from young home-bred calves.
In maximising a calf's defence against disease, control measures include:
- Adequate nutrition of the pregnant cow, including feeding a suitable mineral supplement prior to calving.
- Vaccination of cows for control of any organism(s) known to be responsible for infection on the farm in calves. These include E.coli, rotavirus and coronavirus. In this respect, vaccination alone is not a replacement for good management, good hygiene or good biosecurity. A veterinary practitioner should always be consulted with regard to specific health problems.
- Disinfecting the calf's navel immediately after birth.
- Ensuring that each calf receives sufficient colostrum (first milk) immediately after calving. Adequate intake of quality colostrum is one of the most important factors in ensuring survival and health of the calf. Additionally, there is no point in vaccinating the cow against specific calf diseases unless the calf consumes the colostrum produced.
Colostrum and calf health
The calf is born without any resistance to disease and is completely dependent on immunoglobulins (antibodies) in colostrum as a mechanism to fight disease in early life. Prevention of disease begins with the effective transfer of immunity to the new-born calf through adequate intake of colostrum -- this is known as passive or humoral immunity. The immunoglobulins obtained from colostrum must be consumed within the first few hours of life in order to provide the calf with a disease defence mechanism until it builds up its own resistance through its own active immune system. A calf that does not receive adequate immunoglobulins at birth is very susceptible to pathogens such as E.coli, Salmonella, Rotavirus and Coronavirus. Research at Teagasc, Grange has clearly shown that dairy calves with low levels of immunoglobulins had the highest incidence of diarrhoea, respiratory disease and mortality.
The main factors influencing immunoglobulin levels (concentration) in the calf serum are: (1) time of feeding/suckling, (2) volume of ingested colostrum and (3) immunoglobulin level in colostrum. Consequently, with regard to colostrum feeding, there are a number of main points which must be noted.
1. Time of feeding