The fresh cow heads into the parlor to be milked, and fills the bucket, with low to moderate quality colostrum — now what? Colostrum is often described as liquid gold and serves as a “life giving” solution, equipping the next generation with success through passive transfer while establishing a healthy immune system. But what are the next steps when a cow provides suboptimum quality? Can moderate or even low-quality colostrum be enriched? Sandra Godden, D.V.M., from the University of Minnesota’s College of Veterinary Medicine, took it to the field to learn the best way to enrich suboptimal maternal colostrum and described the results on the “Dairy Science Digest” podcast.

“Many producers wanted to know if they could directly add the powdered colostrum replacer into to the maternal colostrum for ease of delivery,” she explained. “We’ve seen a mixed response in the historical studies and wondered if the elevated solution osmolarity was interfering with gut absorption of antibodies.”

The research team enrolled 132 newborn calves and enhanced the colostrum by adding a new concentrated colostrum product. They then compared performance against moderate quality colostrum, high-quality colostrum, and a combination of moderate quality and the concentrated colostrum product fed separately.

Osmolarity and behavior

Dairy producers know the importance of solution osmolarity by feeding milk replacer. When too much powder is added, osmolarity rises, often resulting in scours and bloat. Therefore, the research team was interested in studying the osmolarity of the treatments, specifically when the colostrum replacer was directly added to the maternal colostrum — anticipating it to be high. In fact, the replacer-spiked colostrum resulted in an osmolarity of 540.9 Mosm/kg compared to all other treatments being less than 375 Mosm/kg.

Surprisingly, solution osmolarity had no impact on scour events. The low IgG maternal colostrum group showed the highest fecal score. Biologically, this makes sense as the calves received a lower concentration of IgG to build up immunity.

Researchers wondered if first reconstituting the powdered replacer in water and feeding it in addition to the maternal colostrum would result in an undesirable volume for the calves. Measured by perecent body weight (BW), there was a significant difference, with the reconstituted group being fed 11.4% versus 8.7% of body weight for the maternal colostrum groups. However, this volume had no impact on the calves’ appetite at the next feeding.

Health impact

There was good news for the field regarding the health response, which was measured by blood serum IgG concentrations and total days scouring. “Directly adding the colostrum replacer to moderate quality colostrum resulted in equal response to the calves that received high quality maternal colostrum,” explained Godden. “However, we were surprised to find the reconstituted treatment fed in addition to the maternal colostrum didn’t get the same bump in IgG.”

What was not surprising was that the “negative control” calves fed a moderate quality colostrum achieved lower serum IgG levels, emphasizing the importance of a quality colostrum program on the success of replacements.

Collecting blood samples and measuring serum total protein as a metric of success was encouraged. The calves don’t lie. Benchmarks for serum total protein (g/dL) measurements for calves fed maternal colostrum are as follows:

• > 6.2, excellent
• > 5.8, good
• > 5.1, fair

An excellent calf program would have a minimum of 70% to 80% of at 5.8 or greater. If you find that your levels are not meeting the benchmark standards, work with your herd veterinarian or extension specialist to identify ways to improve quality, quantity, quickness, and cleanliness.

Not all are created equal

Godden cautioned that not all colostrum replacers are the same. Preference should be given to lacteal derived from maternal colostrum stored and sold by dairy producers, rather than replacers using spray-dried serum or plasma as their sources of IgG. Serum-derived replacers may lack the same level of nutrients and bioactive compounds, therefore resulting in a lower performance when compared to maternal colostrum-derived replacer. She also reminded producers to ensure quality by checking if the replacers are USDA licensed.

“Producers should be careful extrapolating these results to other replacers in the market,” Godden warned. “The replacer we tested averages about 10% fat rather than the more normal concentration of 30% to 35% fat. This, plus protein differences, could change the way abomasal emptying occurs. However, this product was found to be safe and effective to directly apply in maternal colostrum in the field.”

These findings were summarized in a peer-reviewed open access Journal of Dairy Science article found at: www.journalofdairyscience.org. To learn more, listen in to the monthly podcast, “Dairy Science Digest” on your favorite podcast platform.