When & How to wean your calves
The most important thing to know about weaning your calves for your 100% Grass-fed operation is, when is the rumen developed enough to utilize forages? On our farm, we do not separate the calves from the heifers/cows to wean them. We allow them to wean naturally. Generally by the time the calves are 7-8 months of age the heifers/cows have had enough, and persuade the calves to satisfy their appetites with forages. It’s a lot less stressful on the animals and us! But if your operational plan’s include separating the momma from the calf, it must be able to obtain sufficient nutrients from the forages or hay it consumes after weaning. Many of these nutrients are provided by ruminal fermentation, so the rumen must be "up to the task" before the calf can be weaned. But, most producers don't measure "rumen development". They typically rely on some other criteria for weaning. One of the most common criteria that is frequently used is the age of the calf. Most beef producers typically wean their calves at 6 months of age.
If you are on a dairy farm and need to wean your calves at 4-6 weeks of age (which I don’t recommend), You need to know how much starter does the calf have to eat to be ready for weaning? Well, it depends somewhat on who you ask. A good general rule of thumb is when a Holstein calf is consuming 2 lb (1 kg) of calf starter per day for two consecutive days, then it will be ready for weaning. Jerseys are a little different, in more way’s than one. They're ready to be weaned when they are consuming about 1/lb. of starter per day. This usually occurs about 5 weeks of age. But if your 100% Grass-fed, you don’t need to worry about that!
Preparing the calf for weaning means ensuring that it is healthy, has adequate immunity, is kept dry and comfortable/warm, and is allowed access to fresh or dry (not dusty) hay to develop ruminal function. After weaning, calves must derive all of their energy and protein from their forages, whether it is fresh grass, hay, or haylage.
If your "forcibly weaning", as I like to call it when you separate the calf from the heifer, changes in environment & housing can add to the weaning stress. For many years, Grass-based producers have fed forage (primarily hay), to calves to promote ruminal development. The common reason was to give the calf the "scratch" needed to start the workings of the rumen. Forages are also important to promote the growth of the muscular layer of the rumen and to maintain the health of the epithelium. Rumen papillae can grow too much in response to high levels of VFA - when this happens, they may clump together, reducing the surface area available for absorption.
If your animals are going to be 100% grass-Fed, that mean they NEVER EVER have had anything but GRASS in their lives. Don’t try and cut corners by "supplementing" or "treating" your weaning calves with a starter or grain. Your calves will not eat hay if grain is offered. In the long run you’ll be making your life and the calves more stressful to transition to pasture.
Always keep in mind that the calves nutrient requirements will be different than your other various aged cattle. They have very high energy requirements while their rumens adjust to a no milk diet. Good quality legume hay such as a mix of Alfalfa, Red & White clovers and 50% Grass can have enough energy to support growth of weaned calves if your proportions of legumes and grasses are correct.
You also have to keep in mind that your cattle and calves will not grow as fast or produce as much milk in a dairy setting as your neighbors whom push starters, grains and silage into their cattle. But trust me, your calves & cattle will be healthier, happier and in the long run, more profitable because you will have little to NO VET BILLS. Our 100% Grass-fed BEEFALO are proof of that. But than again they are the perfect combination of Carcass & Quality.