3 Pillars of Calf Nutrition, Maintenance, Growth, Immunity

There are many opinions on how dairy calves should be fed. Some say more is better, some are committed to feeding two quarts twice a day. We are going to do a little digging into what that calf does with what you feed them, and how it impacts both the calf and your bottom line. 

First and foremost is maintenance. Maintenance is not optional. This includes things like breathing, pumping blood, digesting feed, and blinking. One of the most important tasks of calories used for maintenance is maintaining the calf’s body temperature. This takes calves a fixed amount of energy, and there’s no way around it. By fixed, it is referring to temperature and size.  Now, it takes different amounts of energy depending on the time of year and conditions, and it’s important to mention it when we talk about calf nutritional needs because it is a factor in calculating calorie intake needs. 

Here is an example:

An 85 lb. calf at 60F needs approximately 1.4 Mcals (or 1,400 calories) per day to maintain it’s body. Say the temperature outside drops to 32F, those maintenance requirements almost double to 2.3 Mcals. 

Same for a 150 lb. calf. At 32F that 150 lb. calf needs 2.6 Mcals per day to maintain, but at 60F, that same calf only needs 1.2 Mcals.

As you can see by those two brief examples, temperature is a huge factor in how many calories are being used for maintenance, along with the size of the animal. 

Don’t worry, this will all make sense in a minute. 

Next up is growth and immunity. I am going to discuss them both together because it’s kind of a tug of war with these two factors. Let me explain why. 

Say you are feeding an 85 lb calf in the winter, so it’s around 40F outside. You are feeding 2 quarts of 21/19 milk replacer at 14.5% solids two times per day. 

With those parameters, that calf needs 2.1 Mcals per day for maintenance and 1.23 for growth to gain 1.5 lbs per day. Well, on that specific diet, after the calf’s maintenance needs are met at 40F, that only leaves her enough calories to grow 0.3 lbs/day. 

BUT this does not include any “buffer” calories for a health challenge. This calf on this diet can only gain .03 lbs per day if everything goes perfectly. This is partly why I put growth and immunity in second place together. If a calf is sick, and she only has enough calories to maintain and grow 0.3 lbs. per day, she will likely take all of that energy away from growth and use it to fight off whatever she might be sick with. 

PROBLEM: What if she doesn’t have enough calories to do that either?

This is where it will all come together. The calf that’s getting the diet above of 2 quarts twice a day of 21/19 at 14.5% solids in the winter, the calf doesn’t have a huge opportunity to grow as it is, but if she has any kind of health challenge that takes over those growth calories, the calf is headed down a not so promising path. In that situation, the calf has a few options: stop growing and use the calories to fight the infection, stop growing and hope there are still enough calories for maintenance, or die. 

So, what are you supposed to do?

There are a couple options. 

Of course, feeding more milk is the simple answer, but that’s not something that’s in everyone's budget (our’s included). But, say you are able to feed more milk. Just bumping that calf up from 2 quarts 2x to 3 quarts 2x will provide the calf with an additional 1.3 Mcals per day. That might not seem like a lot, but that is enough to take them from gaining 0.3 lbs per day to 1.1 lbs of gain per day. It also gives that calf that many more calories to overcome a health challenge. 

If you fed the 3 quart diet, it would cost you an extra $40 per calf. If you prevent that calf from getting one treatment of Baytril, you already made $16 of that $40 increase in costs, strictly in medication. Not to mention the cost of labor, needles, syringes, etc. AND the negative impact treatments have been proven to have on future milk yield! That’s just the money in your pocket today. Imagine how fast you will get that $40 back once she gets into the milking herd. 

Say you can’t afford to feed more milk. What else can you do? Keep additional stressors low. Good colostrum, calf jackets, dry bedding, shelter from wind, good ventilation, access to clean, dry starter feed, clean feeding equipment, etc. Take calf jackets for example, a calf jacket can add roughly 10F to the real feel temperature to the calf. That translates to about 0.6 Mcal less needed for the calf! The better you manage these factors, the better off every calf will be. 

Lastly, drive starter intake. Start is a source of both calories, and getting that big rumen heater running. Doing things like offering warm water after milk and keeping feed fresh can make a huge impact on starter intake and subsequently calorie intake.

These are just a few ways to show how maintenance, growth, and immunity impact a calf. This is by no means the entirety of it, we would be here all day. All we hope to do with this article is challenge you to look at your calf program from a different perspective. 

If you are looking to take a deep dive into your calf program this winter, give us a call. We can help you calculate caloric needs, offer management ideas, and lend experience from raising our own calves.