Colostrum is vital for protection against diseases of the newborn, because it is the source of the antibodies that defend against these diseases until the animal can develop its own defences. Unfortunately many calves have inadequate circulating antibody due to poor colostral absorption. Ensuring an adequate intake of colostrum in the newborn calf requires good stockmanship, as it can be affected by many factors.
A newly born strong healthy calf should suck for 25 to 30 minutes consuming approximately 7% of its bodyweight; this first feed should take place within the first 6 hours of life. The ability to absorb these antibodies is quickly lost after the first feed and so plain milk should never be given prior to colostrum. The second feed increases the efficiency of absorption of the first feed and within about 12 hours the calf will suck approximately half as much again. The final amount of protection the calf gets is therefore governed by the quality of the colostrum, how quickly the calf gets it and the quantity it drinks. Minimum intake should be 4 litres in these first 6 hours.
Many factors are involved; these can be grouped under three main headings:
Colostrum quality decreases with:
- Foremilking, do not milk out before calving. Thus cows which ‘leak’ milk for some time pre-calving will have reduced quality colostrum and those calves should be supplemented.
- Subsequent milking, the antibody level decreases with each milking.
- Short dry period, insufficient time for the cow to prepare.
- Immaturity, heifers too young.
- Reduced immune status of the mother.
The speed at which a calf receives colostrums
- Decreases with: Bad calving/Milk fever/white muscle disease/ other
- Poor udder or teat conformation
- Distractions (other cows, calves, predators etc)
- Poor flooring or rough terrain.
- Increases with: Good stockmanship
- Calf vitality (certain breeds)
- Strong mothering instinct
- Breed of mother
- Heifer or cow
- Husbandry system
- Calf vitality
- Mothering instinct If any of the adverse factors are in play the calf should be supplemented ideally with its mother’s colostrum or some from frozen supplies of first milk only. This can be administered by bottle or stomach tube as circumstances dictate. The recommended minimum is 7 pints in the first 6 hours of life. Storing colostrum for future use is an important way of ensuring that all newborn calves (and lambs) receive the protection they need at the start of their lives. If there is any doubt as to whether a calf has received sufficient from its own mother the stored colostrum can be used as supplement or replacement.
Many colostrum substitutes have come onto the market in recent years and while most of these have some benefit they are not as effective as colostrum. In my opinion they are best used as a supplement if necessary or, as a replacement only if no colostrum is available. They can be expensive and in the current market place storage is a more economic option. The two main methods of on-farm storage are readily available these are freezing and fermentation.
This is probably the easiest method of storage although to store any amount a dedicated freezer will be required. It is advisable to freeze only colostrum from the first milking of non-mastitic healthy cows, though colostrum from older cows can be used. Cows can be vaccinated against Rota and Corona virus, the colostrum stored and given to multiple calves at birth to give protection against rota and coronavirus, both of which can cause scouring calves. The colostrum can be stored in 1.5 litre (approx. 3 pint) packs using plastic bags, empty icecream cartons or my favourite plastic lemonade bottles. When needed for use these can be thawed out fully using a warm water bath. Microwaves should be avoided as they can denature some of the proteins rendering the colostrums of little value to the calf.
Somewhat more labour intensive, but this allows storage of larger amounts and is probably of most use in herds with tight calving patterns or where calves are pail fed. This method virtually pickles the colostrum, like good well made silage and undesirable micro-organisms are killed. Colostrum stored at ambient temperature turns sour by about the sixth day resembling thin, liquid yoghurt. I do feel that adding some natural (unpasteurised) yoghurt to the mix can enhance this process. In this state the colostrum should keep for some weeks.
Storage rules for fermented colostrum.
- Storage should be in plastic or plastic lined containers – plastic dustbins are ideal.
- The nutritional content declines through storage and so the colostrum should be used within a few weeks.
- To avoid separation of solids the colostrum should be stirred daily and stirring just before feeding ensures a more uniform product. To reduce the viscosity the colostrum can be diluted 3:1 with warm water before use. Though as with milk do not be tempted to dilute to weaker than 50:50 as this prevents clotting in the stomach and can lead to scour. Colostrum will not protect against a new disease recently introduced and gives little or no help for pneumonia, but it is still the best protection a calf will get at the start of its life.