Regardless of the calf rearing system what happens to the calf during the first hours of life has a dramatic effect upon their health and future productivity. Two things of primary importance will be discussed in this month’s blog. Read more…
Getting them off to a good start – Newborn calf management
Regardless of the calf rearing system what happens to the calf during the first hours of life has a dramatic effect upon their health and future productivity. Two things of primary importance will be discussed in this month’s blog.
The first hours of life
Early exposure of the calf through the first hours of life determines establishment of the “biome” or population of bacteria which populate their respiratory and digestive tracts. We know that some bacteria are very desirable to the young animal while some can have negative impact on health and growth.
Some bacteria become established during the passage through the birth canal. However, the environment and quality of the first meal of colostrum may have a far larger impact on colonization of the respiratory and digestive system.
Clean box stalls or calving pens well bedded with straw or a well-drained, grassy pasture encourage a more gradual population of the mucosa with organisms that may facilitate better health. However, if the calf is exposed to manure contaminated bedding or poorly ventilated facilities at birth or they consume colostrum with high bacteria counts from dirty bottles or esophageal feeders high levels of undesirable organisms will populate the mucosal surface of the lungs and digestive system and encourage early onset of poor health.
Research has shown that the arrival of bacteria before colostrum in the small intestine can seriously impair absorption of immunoglobulins (James et al. J. Dairy Science 64:52)
How colostrum will determine success
Since the calf does not receive any immunity from the dam before birth, it depends on absorption of immunoglobulins (Ig) from colostrum. Success means optimizing each of the following:
- Maximum cleanness
Make sure, that the calving environment and all devices used to feed colostrum are clean. This means more than just rinsing the surface with water!
- Excellent handling of colostrumTo minimize bacterial growth, either feed or cool it within 30 minutes to prevent growth of bacteria. When preparing colostrum for storage cool it as quickly as possible by immersing the container in ice cold water to achieve a temperature of < 40oF within minutes, even if it’s going to be frozen later for longer term storage. Refrigerated colostrum should not be fed more than 2 days after harvest.
- The sooner, the better
Feed colostrum as soon after birth as possible (<6 hours). Absorption of Ig declines as the calf ages. A more rapid decrease in absorptive efficiency occurs with a contaminated environment, colostrum with high bacteria counts or use of unclean equipment.
- Follow the math
To achieve desired Ig absorption by the calf, test colostrum with a Brix refractometer and feed that testing > 22 which equates to an Ig concentration of >50g/L.
Moreover, feed enough volume – at least 4 liters.This means the calf receives at least 200g of IgG within 6 h of birth.
Make sure to feed clean colostrum – < 50,000 cfu/ml. Test colostrum for bacteria count as it is fed to the calf.
- Track your success
Track whether you are achieving good transfer of immunoglobulins. The table shown below represents currently accepted goals for colostrum management. It recognizes that perfection as a goal is not reasonable and provides a more appropriate recognition of what constitutes good colostrum management.
Success occurs when systems are in place to facilitate the harvest and feeding of clean colostrum in a timely fashion. So, what else do we know about feeding colostrum and handling the newborn calf?
Feeding calves by nipple bottle or tubing them with an esophageal feeder doesn’t seem to affect success of IgG absorption. However, assure that personnel using an esophageal feeder are properly trained to prevent the feeder from entering the lungs! http://veterinaryextension.colostate.edu/menu2/Cattle/TubeDoc.pdf
Relying on the calf to nurse the cow yields inconsistent results.
More than one feeding of colostrum is helpful. Although absorptive efficiency of Ig decreases as the calves age there are benefits provided by other naturally occurring biologically active molecules in colostrum. They promote improved growth and development of the intestinal tissue and foster better early growth and health. Save first milking colostrum for the first feeding, but milk harvested after the milking and until the milk is suitable for human consumption should be fed to the youngest calves.
Feeding the dam’s colostrum to her calf?
In addition to Ig and other factors described above, colostrum also contains immune cells from the dam which are absorbed along with the Ig. Recent research has shown benefits to calf immunity and response to later vaccinations when the calf receives her dam’s colostrum. Unfortunately freezing or pasteurization destroys these cells. Calves fed milk from another cow are not likely to see these benefits.
The need to pasteurize colostrum depends upon the health status of the herd. If the herd is not a “closed” population or there is risk of some infectious diseases, then it is recommended that all colostrum be pasteurized prior to feeding using a batch pasteurization system.
At times there may be an insufficient supply of colostrum of the desired quality for the first meal or it may be difficult to feed fresh, high quality colostrum to the calf. Research has shown equal or better efficiency of Ig absorption with replacers. These replacers are expensive, but the added cost frequently is offset by better growth and health of calves IF it is not possible to feed high quality colostrum early in life! Colostrum replacers also eliminate the risk of disease transfer if the dam is infected with subclinical disease.
Success means developing SYSTEMS that provide a clean calving environment and facilitate harvest and feeding of high-quality colostrum early in the life of the calf.
Remember, let’s do what’s right for your calves!
Bob James – Calf Blogger