FROM THE FARM REPORT: COLOSTRUM HANDLING & PASSIVE TRANSFER... NOT A PASSIVE REQUIREMENT FOR CALVES

The chain of events following colostrogenesis in the cow, to collection, storage, and calf consumption of the colostrum is an important process to manage on the farm. The timing of collecting colostrum, as well as the proper handling and storage, play key roles in the quality of colostrum being delivered to the calf. Furthermore, minimizing bacterial contamination from the cow’s udder, milking equipment, storage vessels, and feeding equipment will help maintain clean colostrum. Surveys from 2017 found that 89% of large dairy farms in North America store colostrum. Handling colostrum may look different on each farm, but it’s critical for maintaining colostrum quality and cleanliness, and giving calves an optimal start to life.

The timing of the first colostrum collection is an important first step. The interval between calving and first milking positively impacts colostrum quality, specifically IgG concentration. Morin et al. (2010) showed a significantly higher IgG concentration when colostrum is collected within 3 hours of calving, and that delaying first milking leads to a dilution of colostrum due to lactogenesis and increased milk production (Fig. 1).

Once the colostrum has been harvested, proper storage is essential to maintaining high-quality, bacteria-free colostrum. Storage can be divided into short-term and long-term strategies. Short-term storage focuses on refrigeration 39°F (4°C) or storing colostrum at room temperature, which can be variable depending on location. Refrigerated colostrum should be used within 1-2 days of being stored. Studies have shown increased bacteria levels and lower calf IgG levels with storage at room temperature. A study conducted by Cummins et al. in 2017 (Fig. 2), showed colostrum stored at room temperature, in this case 71°F (22°C), had 42 times greater bacterial content and 2 times lower serum IgG levels after 2 days compared to refrigerated samples 39°F (4°C).

Figure 1. The relationship between concentration of IgG in colostrum and time after calving. , (Adapted from Morin et al., 2010).

Figure 2. (1) fresh pasteurized colostrum (pasteurized and fed to calves immediately after collection; PST); (2) fresh colostrum (fed immediately after collection but not pasteurized; FR); (3) colostrum stored at 4°C in a temperature-controlled unit for 2 d before being fed to calves (ST4); (4) colostrum stored at 13°C in a temperature-controlled unit (Binder GmbH, Tuttlingen, Germany) for 2 d before being fed to calves (ST13); and (5) colostrum stored at 22°C in a temperature controlled unit for 2 d before being fed to calves (ST22) (Adapted from Cummins et al.,2017).

Long-term storage consists of freezing and thawing colostrum. A scoping review of on-farm colostrum management practices for optimal transfer of immunity in dairy calves by Robbers et al., 2021 showed that thawing by waterbath up to 104°F (40°C) is best and that microwave methods should be avoided because it unevenly heats the colostrum, potentially denaturing proteins. While a single freeze-thaw cycle doesn’t reduce IgG levels in colostrum, repeated freezing and thawing has shown significant decreases of 7.8% and 7.7% on the second and third cycles (Morrill et al., 2015).

The size and shape of the container used to store colostrum will affect the method of storage. For instance, Cummins et al., 2017 used sterilized 2 L bottles, but there are several options available for storage. At Miner Institute we use a 1 gallon (4 L) single-use bag held in a plastic reusable holder, making freezing, storage, and thawing easier.

Pasteurization of colostrum is a method used to limit the growth of bacteria and pathogens in colostrum to minimize risk to calf health. Pasteurization temperatures and times can impact the colostrum quality and subsequent calf IgG serum levels. Robbers et al., 2021 surveyed several studies that show that heating <140°F (<60°C) for 30 to 60 minutes did not affect or had minimal effect on colostrum quality, compared to temperatures 140°F (60°C) or greater, which had a significant loss in IgG concentration. Another study showed heating the colostrum at 145°F (63°C) for 30 minutes had no impact on calf IgG serum, as opposed to heating at 168°F (76°C), which showed lower calf serum IgG. While the studies Robbers et al., 2021 reviewed showed no difference in the IgG content of pasteurized and unpasteurized colostrum, calf IgG values were significantly higher for calves fed pasteurized colostrum.

The industry has started to use the three Q’s, Quality, Quantity, and Quickness, as colostrum management guidelines. Occasionally you will also see Quantifying the Transfer of IgG and sQueacky clean added to the list of Q’s. While these typically apply to the delivery of colostrum to the calf, they also apply to the harvesting and storage of colostrum. A timely first milking with proper handling and storage can help your farm capitalize on high-quality colostrum with minimal bacterial growth. While there is no “one size fits all” solution for every farm, there are a multitude of resources to help guide farmers. Regardless of how the individual farm manages colostrum, having protocols in place and training staff on proper colostrum handling will ultimately pay off in a healthier young stock population.

*References available upon request

— Robert Navaroli

navaroli@whminer.com