When calves are orphaned or left behind when they are very young, they cause a lot of problems for cow-calf operations. These things can happen when dams die at or soon after giving birth, or when a cow or first-calf heifer has health or behavior problems that keep her from properly caring for her calf. Calves born to cows that aren’t giving enough milk or that are multiples may need extra care as they grow up. In the dairy industry, calves are routinely separated from their dams at very young ages. The resulting calves are sometimes referred to as “bucket” or “bottle” calves.
As a beef cattle farmer, you pour your heart and soul into raising healthy, thriving calves. An important part of their development is transitioning from milk to grass and grain But when is the right time to introduce calves to solid foods like pasture grass? In this article, we’ll explore the key factors in determining when to wean calves off milk and start introducing grass into their diet.
Why Grass is Essential for Beef Cattle
Before looking at when to start feeding it, let’s consider why grass is so vital to calves and cattle. As ruminants cattle are built to digest fibrous grasses and convert them into energy. Grass makes up the natural, ideal diet for bovines.
Fresh pasture provides cattle with
- Protein for growth and development
- Fiber for digestion and rumen function
- Vitamins, minerals, and antioxidants
- Low cost, readily available food source
Allowing calves to graze on high-quality pasture grasses supports their health while reducing reliance on grain feeding. Access to grass is linked to fewer instances of acidosis, bloat, and other health issues in cattle.
Signs Calves Are Ready for Grass
Determining when to introduce grass into a calf’s diet depends on multiple factors. Here are some signs that a calf is developmentally ready to start consuming grass:
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4 weeks old – The rumen is developing and calves will start exploring solid foods.
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Consuming 1.5-2% of body weight in milk – Reduced milk intake shows readiness.
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Doubled birth weight – Excellent benchmark for maturity and ability to digest grass.
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Active grazing and rumination – The calf nibbles grass and frequently chews cud.
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Rumen is round and full – Indicative of fermentation and functionality.
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Smooth, glossy coat – Sign of good health and nutritional intake.
Using these benchmarks helps determine the optimal timing for introducing grass into the calf’s menu.
Good Practices for Transitioning to Grass
When the signs point to readiness, here are some tips for transitioning calves successfully:
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Start with high-quality leafy pasture grasses like ryegrass. Avoid mature grasses.
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Introduce grass gradually over 2 weeks, reducing milk availability.
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Make grass continuously available to encourage grazing.
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Maintain optimal pasture height of 6-10 inches.
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Ensure adequate fencing for rotational grazing and moving calves.
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Provide clean water, mineral supplements, and shade access.
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Monitor health and weight gain; adjust diet as needed.
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Separate cows and calves but maintain visual contact.
Following these good practices sets your calves up for smooth sailing as they embark on eating grass.
Common Pitfalls to Avoid
While the transition can go smoothly when done properly, there are a few potential pitfalls to watch out for:
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Sudden complete weaning without gradual reduction of milk. This can cause gut health issues.
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Allowing calves to over-gorge on rich spring grass. This can lead to bloat and other complications.
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Neglecting parasites or illness. Calves need routine deworming and health monitoring.
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Providing pasture that is too short, overgrazed, or of poor nutritional quality.
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Letting calves graze with adult cattle. The adults will dominate the feed space.
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Failing to provide clean water, salt licks, and shade. These are essential for grazing cattle.
By taking some precautions and avoiding these common mistakes, you can ensure a smooth transition when your beef calves start eating grass.
Individual Factors to Consider
While the guidelines provided serve as useful benchmarks, each calf is an individual with unique needs. Some additional factors to consider:
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Breed – Some breeds like Jerseys may mature faster than late-developing breeds.
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Birth weight and genetics – Lower birth weight calves may need more time to grow.
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Health status – Illness can delay a calf’s ability to transition.
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Milk production of the mother – Calves of high milk producing dams need more weaning time.
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Available pasture and weather – Grass quality and quantity affects timing.
Taking the calf’s individual attributes into account helps fine-tune the transition plan. Work closely with your vet to determine what’s best for each animal.
Determining the optimal time to introduce beef calves to grass is part science and part art. While guidelines provide a framework, each animal will communicate their readiness through behaviors like grazing, rumination, and milk intake. Keys to success include high quality pasture, gradual transition, and proactive health management. As a steward of your cattle’s wellbeing, your careful observance and judgment helps ensure calves thrive on grass.
Feeding the Young Calf
For the first few months of their lives, bottle calves must be either fed milk replacers by humans or grafted onto nurse animals. These young calves are not yet mature ruminants, so they need a milk-based diet. Every day, a calf needs to eat milk or milk replacer equal to about 8% of its birth weight. Offer bottles twice daily in two equal feedings. Follow feeding directions on product labels. Keep giving the calf the same amount of milk replacer as it grows, but as its appetite grows, give it starter feeds and good quality hay. Make clean water available for the calf, as well.
Grafting to a Nurse Cow
If you successfully graft a calf onto the side of a cow that is nursing, you won’t have to bottle feed the baby, which saves you time and money. Besides providing a milk source for the calf, it also gives the calf protection from predators. Putting a calf on a beef cow that has lost her calf or on another nurse cow (usually a dairy breed) that was bought just for that purpose takes care and time. It may also be necessary to graft if the dam doesn’t want to nurse her own calf at first. Women who just gave birth to their first calves or dams who had more than one baby may be more likely to have this happen.
Start by separating lactating cows and newborn calves from the rest of the herd with fencing. This will give the calf a chance to get close to the cow that you want to graft onto. Provide adequate shade and water in the pen, along with forages or other feedstuffs for the cow. When introducing the cow and calf, it works best if you don’t bottle feed the calf until it’s full before trying to get it to nurse from the cow. A tight-bagged (full-uddered) cow and a hungry calf are more likely to result in successful grafting.
Put the skinned hide (skin over the back and tail) of the nurse cow’s dead calf on the grafted calf and rub or tie it on. This will transfer the scent and help the cow accept the new calf. Afterbirth and commercial products consisting of synthetic pheromones also can help in grafting. These smells might help for the first two or three days, but not much after that.
The cow and calf may be too distracted by human presence to nurse or bond when first introduced. Give them some time to be alone together without any other distractions. Then, either watch them from afar without being seen or check them later to see if they are nursing, such as a full belly on the calf and slick teats or less udder filling on the cow.
At first, let the nurse female take the calf without being held back, but don’t wait too long for nursing to happen before using restraint. It is critical that newborn calves receive adequate colostrum and nutrients in early life. Also, dehydration is a risk that must be addressed through forced feeding situations if necessary. If the cow kicks or butts the calf over and over and won’t let it nurse when it’s not restrained, put the nurse cow in a squeeze chute with the bottom sides cut out so the calf can nurse twice a day. Repeat until the cow claims the calf willingly.
If the nurse woman had a hard birth or is upset about losing her calf, be extra careful when you touch her and keep a close eye on her for signs of distress or health problems. Even if a nurse female agrees to have a grafted calf, she might not be able to milk enough to support the calf. In some cases, the cow may dry off (discontinue lactation). Do not assume that a suckling calf is getting adequate nutrients through nursing. Closely monitor the calf’s weight and condition, and supplement additional nutrients as needed.
If you do not have a nurse cow, use a milk substitute that has at least 15% fat and 22% crude protein. Mix milk replacer with warm water to help it dissolve better and make it taste better to the calf. If you can’t find a hot water source close to where you’ll be feeding, bring warm water with you in a thermos or another insulated container. Then, mix the warm water and milk replacer powder together when ready to feed the bottle. Keep the temperature of the mix consistent between feedings and not more than 100°Fahrenheit. Also, use the same amount of milk replacer in the mix each feeding. Make sure to stir or shake the powder and water together well so that all of the powder is dissolved.
Use separate bottles for each bottle calf to limit risk of disease spread. Sanitize all feeding equipment after each meal. Keep bottle feeding supplies away from areas where food is prepared for people to protect their health, especially the health of young children who are more likely to get sick.
If a calf is born to nurse its mother, it may need to be taught how to drink from a bottle. Start by inserting one or two fingers into the calf’s mouth. As the calf begins to suck, insert the bottle nipple in its mouth. While the calf is backed up against a solid fence, wall (corner is best), or vehicle, you may need to straddle or stand next to it and hold its head up. This position for the head will also help close the esophageal groove that young calves have. This will help milk go straight past the rumen and into the abomasum, which is the “true stomach.”
It may take a while to get lethargic or ill calves to actively suck a bottle. Spend the extra time to get a calf used to a bottle before using a forced infusion of feeding liquid if you can. What if a calf still won’t drink from a bottle? An esophageal feeder, or stomach tube (Figure 1), can be used to feed milk replacer directly to the calf’s stomach. Take extreme care to ensure that the tube is in the esophagus and not the windpipe. Listen to make sure that breathing sounds are not coming from the tube. Sometimes, infusion of milk replacer into the stomach will stimulate a calf’s appetite. Weak calves may require smaller and more frequent feedings. Continue to monitor calves for signs of unthriftiness such as poor growth, scours, and a “pot-bellied” appearance. Make a plan for how to prevent and treat scours based on the advice of a vet who knows about the operation. Extension Publication 2551 Identifying Sick or Injured Cattle provides additional insight about monitoring calves for illness.
Figure 1. Stomach tube.
As calves get used to drinking from a bottle twice a day, they may look forward to feeding time and try to grab the bottle. These calves become accustomed to humans feeding them. People often think of bottle calves as calm or tame, but the person who is handling the bottles needs to be careful not to get hit in the head by the calf. This becomes more of a safety concern as the calf gains stature and weight over time. A wire bottle holder can be used to attach a full bottle to a fence so that the person feeding the animal doesn’t have to hold the bottle. Make sure to take the bottle off the calf when it’s empty so the calf doesn’t swallow too much air.
You can also feed milk replacer in buckets, but be careful that calves don’t step in and tip over the buckets. Make sure that buckets are not too tall for calves and are secured. To teach bucket feeding, place fingers moistened with milk into the calf’s mouth as described earlier. As the calf begins to suck, gently lower its mouth into the bucket of warm milk. Keep its nostrils clear of the liquid. Repeat as needed until the calf drinks on its own.