From what I’ve seen, feed cost per liter can actually be better with longer lactations, but it depends on the cow and how you manage late lactation. If she’s a steady producer and doesn’t crash after 300+ days in milk, you’re spreading feed costs over more milk without the big energy demands of early lactation.

The risk is if she drops too far in yield — then you’re feeding a cow that’s just maintaining herself and not giving enough milk to pay for the ration. I’ve had the best luck keeping condition in check, feeding more forage and less high-priced concentrate once production starts tapering off. That way, the later months are still profitable without blowing the feed budget.

Feed Costs per Liter: Shorter vs. Longer Lactations

Extending lactation can impact feed costs per liter in several ways. Here's a breakdown:

Shorter Lactations (e.g., 305 days):

• Milk Yield: ~10,000 liters

• Feed Intake: ~6,000 kg

• Feed Cost per Liter: €1.00 MDPI+5Your Article Library+5ABC of Agri+5Kingshay+3Western Canadian Dairy Seminar+3standarddairyconsultants.com+3

Longer Lactations (e.g., 400 days):

• Milk Yield: ~12,000 liters

• Feed Intake: ~7,200 kg

• Feed Cost per Liter: €0.83showme.comAlltech, Inc.+3Engormix+3ABC of Agri+3

While feed intake increases with longer lactations, the feed cost per liter decreases due to higher total milk production. However, it's essential to consider factors like declining milk yield in late lactation and increased maintenance costs. Maintaining cow health and optimizing nutrition are crucial for maximizing profitability.