It’s a bit of a “wonder nutrient” in dairy nutrition. Choline is neither a vitamin nor a mineral, but an essential element in dairy nutrition, nonetheless.
This water-soluble micronutrient it commonly grouped in the B-vitamin family. Nearly all mammals synthesize choline, but must also consume it in their diets to ensure adequate levels.
Feeding choline to ruminants was challenging until rumen-protected formulations became available a few decades ago. Without protection, choline is quickly degraded in the rumen before it can be absorbed for benefit. Encapsulation of choline allows it to pass through the rumen into the small intestine, where it can be absorbed and utilized.
Since the advent of rumen-protected choline (RPC), dairy researchers have explored its effect on lactating dairy cows in great depth. Dr. Jose Santos, researcher in the Department of Animal Sciences at the University of Florida, has declared RPC a vital nutrient for transition cows, due its positive effects on liver function, phospholipid synthesis, and nutrient transport as cows need to pull out all the metabolic stops to launch successfully into lactation.
In a retrospective analysis of published studies examining RPC supplementation to more than 1,300 transition cows, Santos and his colleagues found that the practice led to: (1) an increase in average energy-corrected milk of 4.85 lb./day; (2) a significant increase in milk component yield; and (3) significant deceases in the incidence of retained placenta and mastitis.
Santos and his team have continued to study choline in greater depth, including its beneficial effects on helping cows cope with heat stress. Along the way, they discovered another interesting finding – for calves.
“We’ve shown that male calves born to dams supplemented with rumen-protected choline and fed colostrum from similarly treated dams displayed improved immunoglobulin absorption,” he stated. “These same calves exhibited reduced inflammatory responses when exposed to bacterial compounds simulating infectious disease.”
As they followed those calves from choline-supplemented dams through life, the University of Florida researchers found that they grew faster than their herd mates not exposed to choline in-utero, at a rate of 0.11 lb./day. As a result, they were 79 lb. heavier at first calving. What’s more, they produced an average of 1,155. more milk in their first lactations.
Dr. Heather White, researcher in the Department of Animal and Dairy Sciences at the University of Wisconsin-Madison, recently published a study that looked specifically at the outcomes of calves in the beef production chain after their in-utero exposure to choline.
The Wisconsin team examined the effect of the feeding of RPC to pregnant Holstein dams on the resultant growth, feed efficiency (FE), metabolism, and carcass quality of their Holstein X Angus offspring. Of the 47 calves born in the study, 17 were male and 30 were female. The dams were divided into 4 feeding groups – a control group receiving no supplemental choline, and three supplemented groups with RPC fed at various doses.
White and her colleagues found that RPC supplementation to dams produced calves – regardless of sex – with significantly higher daily gain; hip and wither height; kidney, pelvic, and heart fat at slaughter; and marbling score. The calves from choline-supplemented dams also had improved gut integrity markers when facing bloat challenges.
These benefits were realized despite the calves having never been fed RPC themselves.
“Considering the importance of marbling in carcass quality, the potential of RPC to positively influence offspring performance could be beneficial for further enhancing value of beef X dairy cattle at slaughter,” observed White.
