At a recent producer meeting the speaker reminded us of how biological systems rarely result from chance. In general the systems are designed in specific ways to get specific results. This meeting was about colostrum composition and why it is not just composed of antibodies for calf survival. This is an active area of research with more data coming. This newsletter will be a refresher on colostrum with a section on the importance of colostrum for long-term productivity of heifers. The composition of colostrum starts with maternal antibodies but the rest of the components have a major impact on which heifers will survive long enough to reach the milking string.
First – The Basics
Cleanliness. Clean and sanitize everything involved with the harvest, feeding and storage of colostrum. This includes the udder, lids of buckets, bottles, nipples, feeders – everything that comes in contact with the colostrum. Timeliness. Harvest colostrum from all cows within 4 hours of calving. After 6 hours post-calving colostrum quality begins a rapid decline. Feed calves at least 4 quarts (larger calves) or 3 quarts (<70 lb calves) within 1 hour of birth. Follow this with at least 2 more quarts within 12 hours of birth.
Pasteurization? There is not a consensus on whether colostrum should be fed raw or after pasteurizing. The advantage to pasteurizing colostrum is disease control. However, many operations are able to achieve very good calf survival with raw colostrum. This step is one best discussed with your management team closest to the situation.
Opinions also seem to vary on whether you should freeze some high quality colostrum for emergency use. This one is a little easier – Yes, you should have some frozen colostrum on hand. Frozen colostrum is better than none or colostrum replacers. It can come in handy during certain seasons for use as the second feeding for example.
NOTE-Colostrum replacers are acceptable. But nothing replaces high quality, fresh colostrum.
Storage and Feeding Basics
- Feed fresh colostrum using cleaned and sanitized equipment within 1 hour of birth.
- If colostrum will not be used immediately, store colostrum in the refrigerator for 2-3 days. Rotate the inventory for first-in, first-out use.
- If adequate supply for rotation is available in the refrigerator freeze a few days’ worth of high quality colostrum. While frozen colostrum has a long shelf life, it is best to also rotate this inventory.
Colostrum and short-term survival
(Life and Death)
During gestation the dam provides immune protection to the fetus. All nutrients are supplied in a sterile environment. As soon as the calf is exposed to the outside environment its body is under attack. The calf has no natural disease protection at this time. So the two competing factors that have to be addressed are disease/pathogen load and how quickly can we get the calf’s immune system started. Load has to be minimized through calving conditions, such as plenty of clean dry bedding.
The immune system has to be started in the first 24 hours of life. It is only during this time that maternal antibodies can be absorbed in the small intestine. The morphology of the intestinal wall that is initially open to antibody absorption closes gradually until by hour 24 less than 5% of the initial absorptive capacity is left. Antibodies in colostrum are large molecules that have to be absorbed intact. The challenge to the calf is that while the intestine is open to antibodies it is also open to pathogens such as E. coli and salmonella.
Calf survivability through 56 days of age is largely due to early feeding of high quality colostrum. When this is accomplished early calf survival is improved by 5-10 percentage points over calves that only receive a marginal dose of colostrum.
In a confidential conversation with a veterinarian she shared some information regarding calf survival across herds at a medium sized calf ranch.
Total serum protein is commonly used as a proxy estimation of adequate IgG resulting from passive transfer of antibodies from colostrum. At this calf ranch the results are pretty dramatic. The 4 dairies that consistently average 5.4 or higher on total protein have death losses of 2.5 to 6.2%. The herd that averaged 5.4 is the one with 6.2% death loss. While 6.2% calf death loss may seem high the results from the other 2 herds are shocking, yet probably not surprising.
These 2 herds averaged 9.8% and 13.8% death loss for the past 12 months. Obviously the results are not just from inadequate colostrum but the fact is clear – Calves that receive adequate quantity of high quality colostrum are significantly more likely to survive to weaning.
Colostrum and long-term survival
In addition to the benefits of survival and health, giving adequate amounts of high quality colostrum have a number of future benefits that may persist into the second lactation. While immunoglobulins provide passive immunity to the newborn calf, other components of colostrum contribute to growth and performance. Colostrum is the vehicle to supply the calf with growth factors and hormones, which is called the “lactrocine hypothesis”.
Growth hormones such as insulin, prolactin, relaxin, and leptin along with insulin-like growth factors I and II are non-nutritional factors that have long-lasting effects due to enhanced expression of genes, allowing a calf to reach her genetic potential. The research on this topic reports increased rate and extent of digestive tract, uterine, and mammary gland development.
What this means is, in addition to less sickness and lower death loss in calves, feeding of high quality colostrum may lower cull rates in the first two lactations, and support increased nutrient utilization and efficiency resulting in improved growth. The effects of improved uterine and mammary gland development equate to enhanced reproduction and more milk produced in the first and possibly second lactations. Research results on these two things lack consistency, but do indicate that improvements are made. For example, a summary of three research trials on the topic show improved milk yield in the first lactation of 700 pounds to over 1,500 pounds from calves receiving high quality colostrum compared to calves receiving inadequate passive transfer.
This newsletter topic has been on our desk for a few years. The main impetus for it has been the observation that from September through January many Jersey herds and a few Holstein diaries were significantly short on colostrum production. Two hypothesis have been presented.
- Does season impact quantity and quality of colostrum? During the fall, with shorter days, milk production is reduced. But does this also mean colostrum production drops for the same reasons?
- Heat stress during the dry period lowers future production. Does this also reduce colostrum production?
Both of these seem likely, yet the data is incomplete. There is a multi university collaborative research project on-going that is attempting to find the cause for seasonal slumps in colostrum production, especially in Jersey herds. As the data becomes available we will pass it on.
NOTE-It is important to remember that volume is not a good determinant of quality. What we are primarily looking for is getting an adequate amount of maternal antibodies absorbed to give the calf protection. Adequate volume certainly helps with getting enough protein, fat, and vitamins into the calf but short-term survival is all about antibodies.