Milk vs Starter: Balancing Calf Growth and Feed Choices
Feeding more milk or milk replacer to calves has become increasingly common, offering improved early weight gain. However, this approach reduces starter feed intake—a crucial factor for smooth weaning and rumen development. A study conducted with 73 Holstein heifer calves in Iran examined how milk levels and starter composition affect growth outcomes.
The calves, averaging 40.6 kg at birth, were assigned to two milk feeding programs: a moderate level (peaking at 4.5–5 liters/day) and a high level (peaking at 8.5 liters/day). From day 8 to 56, calves received one of three starters differing by crude protein levels (20% or 24% dry matter) and fat levels (3% or 5.5% dry matter). All starters also included 7.5% chopped wheat straw for rumen stimulation.
Results revealed that calves fed high-fat starter (5.5% fat) consumed less starter feed and showed lower average daily gains. In contrast, the best skeletal growth—measured as withers height—was seen in calves receiving high milk and higher protein starter (24% CP). Meanwhile, high milk plus high-fat starter led to the lowest skeletal growth.
Ruminal fermentation supported these findings: calves fed high-fat starter had reduced total volatile fatty acids (VFAs), including reduced acetate and propionate concentrations, which align with lower solid feed intake. Notably, high-fat starters also led to lower protein efficiency, though urinary nitrogen excretion remained similar across treatments.
Dr. Al Kertz concludes that while higher milk feeding supports early weight gain, high-fat calf starters reduce feed intake and should be avoided. Moreover, increasing starter protein beyond 20% did not result in significant gains, contradicting trends favoring high-CP starters. Textured starters—even though costlier per unit—promoted better intake and growth compared to pelleted or meal formats, ultimately offering greater value.
Bottom line for dairy farmers:
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More milk equals more early gain, but monitor starter feed to avoid weaning challenges.
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Avoid adding fat to calf starters—it hurts intake and growth.
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Stick to 20% crude protein starters unless specific performance goals demand otherwise.
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Invest in textured starters for better intake and overall calf growth.