Colostrum: The Nearly Magical Mix
It’s been said by many a scientist and veterinarian that there are no “silver bullets” or “miracle cures” when it comes to raising healthy, productive calves. No pill or potion can outdo the fundamentals of clean, dry bedding; abundant and precise nutrition; and excellent ventilation.
But if anything comes close, it doesn’t come out of a vial or bottle. It comes out of the dam’s udder, right after the calf is born, and it’s essentially “free” of charge. Colostrum, it turns out, is the super-powered serum that has the potential to directly impact calves’ health, growth and productivity, from Day 1 through adulthood.
Colostrum is widely recognized as a critical source of immunoglobulin G (IgG), a protective antibody that helps calves ward off disease-causing organisms until their own immune systems are up and running. Calves’ ability to absorb IgG through the intestinal wall and into the bloodstream declines significantly after 4 hours postpartum, which is why timely delivery of the first colostrum feeding is so important.
Researchers have noted that, in addition to IgG, colostrum packs a veritable goody basket of other benefits for the newborn calf, including other immunity and growth boosters; warmth; hydration; high levels of energy-ready fat; and other important nutrients including fat-soluble vitamins, vitamin B12, and iron.
Just how much of a difference does colostrum make? A group of Chinese researchers examined that issue in a recent study published in the Journal of Dairy Science (Yang et al., 98:7153-7163).
In that study, 24 newborn male Holstein calves received one of three types of feedings on their first day of life – first-milking colostrum, transition milk (harvest from cows 2 or 3 days after calving) or whole (bulk tank) milk. An additional 4 control calves received no feedings, and were euthanized and necropsied shortly after birth to establish a comparative baseline for intestinal structure.
Calves in the feeding study received 4.0 L of their prescribed types of milk immediately after birth, and another 2.0 L at 8 hours after birth. From Day 2 of life forward, all 24 calves received identical care, feeding and housing.
At Day 8 of life, 4 calves from each feeding group were euthanized and necropsied, so the researchers could evaluate the effects of the various treatments on both physical performance and digestive-tract development. Among their findings:
The IgG levels ingested by the calves were 422.4, 231.6 and 3.6 ug/mL for colostrum, transition milk and whole milk, respectively.
The calves fed colostrum had the most advanced and uniform digestive-tract development, with the longest and widest intestinal villus heights and highest crypt depths. Mucosal thickness was also highest for the colostrum-fed group.
In contrast, the villi in the calves fed whole milk were described as non-uniform, sparse, and severely atrophied.
On Day 8, weight gain in the colostrum group averaged a total of 2.2 kg. (4.85 lb.) per head and in the transition-milk group, 1.7 kg. (3.74 lb.) per head. The whole-milk group lostan average of 0.4 kg. (0.88 lb.) per head.
Calves in the colostrum group experienced no diarrhea, and none died during the study. One calf in the transition-milk group had diarrhea. Five calves in the whole-milk group had diarrhea, and 3 of those animals died.
The researchers said their findings reinforced the value of colostrum in establishing immunity after birth, which could assist in reducing the effects of disease-causing organisms, promoting digestive-tract development, and thus supporting growth, health and survivability in calves. Their work further verifies the “magic” that can be worked by clean, high-quality, efficiently delivered colostrum.