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Colostrum for Calves: How Much, How Fast, and When to Use a Replacer

Thu, 08 Oct 2026 17:56:34 GMT

A newborn calf should get colostrum equal to about 10 percent of its body weight, roughly 4 quarts for a Holstein and 3 quarts for a Jersey, ideally within 1 to 2 hours of birth. Use colostrum that tests at 22 percent Brix or higher. When good maternal colostrum is not available, a true colostrum replacer can stand in for it. A supplement cannot.

The basics are covered in our guide to the first 24 hours with a newborn calf . This article goes deeper on colostrum for calves: why timing matters so much, how to test what you have, how to read a replacer label, and how to tube feed safely when a calf will not drink.

Why Does the First Colostrum Feeding Matter So Much?

A newborn calf depends on colostrum for its first antibodies. This transfer of antibodies (mainly IgG) from colostrum into the calf's blood is called passive transfer, and the window for it closes quickly.

According to Utah State University Extension's 2026 colostrum fact sheet , absorption is best within 1 to 2 hours of birth and still acceptable within 4 hours. It drops significantly after 12 hours, and by about 24 hours the gut is effectively closed to antibodies. The same fact sheet cites research in which calves fed in the first hour had clearly higher blood IgG than calves first fed at 6 or 12 hours.

That is why the colostrum plan belongs in place before calving season, not on the night a calf arrives. Clean bottles, a tube feeder, a refractometer, and a stored supply of good colostrum or replacer let anyone on your crew hit that first window.

How Much Colostrum Does a Calf Need, and How Fast?

Feed 10 to 12 percent of the calf's body weight at the first feeding, as soon as possible after birth. Penn State Extension puts that at about 4 quarts for a Holstein and 3 quarts for a Jersey, and calls a first feeding within two hours ideal and within eight hours critical.

Volume matters because the calf needs a total dose of antibodies, not just a few swallows. Utah State's fact sheet sets a target of at least 150 to 200 grams of IgG absorbed, with 300 grams or more for the best results. It also notes that calves offered a bottle drank only about 2.2 liters on average in one study, which is why some calves need a tube to get the full amount.

Plan a second feeding as well. In research cited by Utah State, calves fed 4 liters shortly after birth and another 2 liters 12 hours later had higher IgG than calves given only 2 liters at first. Penn State notes that lower-quality colostrum can be saved for that second feeding or later.

How Do You Check Colostrum Quality Before Feeding?

Test every batch with a Brix refractometer and feed only colostrum that reads 22 percent Brix or higher for the first feeding. Both Penn State Extension and Utah State use 22 percent Brix as the line for high-quality colostrum, which corresponds to at least 50 grams of IgG per liter.

Looks are not a reliable test. IgG levels vary widely from cow to cow, from about 25 grams per liter at the low end to over 130 grams per liter, according to Utah State. Two pails of thick, creamy colostrum can carry very different antibody doses.

Cleanliness counts as much as quality. Utah State recommends these targets for colostrum you feed:

Total bacteria count under 100,000 CFU per mL
Coliform count under 10,000 CFU per mL
Heat treatment, where used, at 140°F for 60 minutes in a pasteurizer or controlled heating system

For storage, Penn State gives two to three days in the refrigerator (up to seven days with potassium sorbate) and six months frozen. Label each container with the cow's ID, the date, and the Brix reading so the best colostrum goes to first feedings.

Colostrum Replacer vs. Supplement for Calves: What Is the Difference?

A colostrum replacer carries enough antibodies to take the place of maternal colostrum. A colostrum supplement does not. Penn State Extension defines a replacer as 100 to 150 grams of IgG per dose and a supplement as 40 to 60 grams, noting that a supplement cannot raise a calf's blood IgG to the standard for successful passive transfer on its own.

Penn State recommends feeding at least 100 grams of IgG and suggests 150 to 200 grams. Products containing IgG are regulated by the USDA Center for Veterinary Biologics, so check the label for the IgG content and follow the manufacturer's mixing and feeding directions exactly. If the label does not list grams of IgG per dose, you cannot tell how much protection a calf is getting.

How Do You Tube Feed a Calf Safely?

Tube feed a calf when it cannot or will not drink enough colostrum, as long as it can swallow. The steps below follow Utah State University Extension's tube feeding fact sheet. If a calf cannot swallow, or is weak or down, call your veterinarian rather than tubing it.

Restrain the calf. Back a standing calf into a corner and hold it between your legs with its head up. A calf that cannot stand but can swallow can be laid on its chest with the head supported.
Measure the tube from the tip of the nose to the shoulder and mark it.
Lubricate the tip lightly and keep the head in a neutral position. Over-extending the neck raises the risk of the tube entering the windpipe.
Slide the tube to the back of the mouth, aiming to the left, and wait for the calf to swallow. Advance it to the mark only as the calf swallows. If you feel resistance, pull back and redirect. Never force it.
Check placement on the left side of the neck. You should feel two tube-like structures: the firm, ridged windpipe and the esophagus with the tube inside. If you feel only one, or feel air coming from the tube, remove it and start over.
Warm the colostrum to 98 to 100°F and let it flow by gravity. Never squeeze the bag to speed it up.
When the bag is empty, kink the tube and remove it in one smooth motion.
Clean it right away: rinse in cold water, wash in hot soapy water, rinse with a chlorine solution and then hot water, and hang it to dry.

Utah State's beef fact sheet suggests 1.5 to 2 quarts per tube feeding and splitting larger amounts when you are unsure how much the calf has taken in. For dairy calves receiving a full first feeding, follow the volume your veterinarian recommends for your herd.

Where Does a Calf Supplement Fit Into the First Feeding?

Colostrum always comes first, and nothing replaces it. A calf supplement fits in as part of the same visit, so the newborn routine stays simple for whoever is on shift.

Start Baby is a direct-fed microbial supplement for newborn calves. Our label directs one full tube within six hours of birth, dispensed slowly on the back of the tongue. That timing means you can feed colostrum first and give the tube during the same trip to the calving pen. Do not give Start Baby to a calf that is unable to swallow, and call your veterinarian for any calf that is weak or down.

If you want to compare products, our guide to reading a probiotic label for calves explains what the guaranteed analysis and strain names tell you.

Colostrum Questions We Hear From Producers

Keep a Tube Ready for Every Newborn

Calving season moves fast. Keeping colostrum, a tube feeder, and Start Baby on the colostrum cart means every calf gets the same routine at its first feeding. Questions about fitting Start Baby into your routine? Call us at (223) 341-9188 to talk through how it fits your calving process.

Written by Glenn Flickinger, founder of Ag Resources Unlimited. Glenn holds a BS in Animal Science from Delaware Valley University and has run his own farm consulting firm since 1992. Read more about Glenn and our family .

Probiotics for Calves: What They Do, When to Give Them, and How to Read the Label

Wed, 30 Sep 2026 01:27:31 GMT

Probiotics for calves are live beneficial bacteria, labeled as direct-fed microbials, given to help a young calf's gut get established. Research reviews show they can improve starter intake and weight gain, though results vary by product. They work best given early, alongside colostrum and good calf care, and the label tells you what you are actually buying.

We make a calf probiotic paste here in Lancaster County, Pennsylvania, so we get these questions often. This guide covers what the research does and does not show, when to give a probiotic, and how to compare products by reading the guaranteed analysis.

What Are Probiotics for Calves?

A calf probiotic is a product containing live, beneficial microorganisms, usually bacteria such as Lactobacillus or Enterococcus, and sometimes yeast. On feed labels you will usually see them called direct-fed microbials.

The reason they matter for young calves comes down to how a calf is born. Penn State Extension notes that a newborn calf's rumen is not yet functional and has no established population of microbes. Within a few days, microbes begin to colonize the gut from feed, bedding, and the environment around the calf. A probiotic is a way to put beneficial organisms into that picture early, rather than leaving it entirely to chance.

Our own product, Start Baby , is a direct-fed microbial paste given as one tube at birth. Its label lists four strains: Enterococcus faecium, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus plantarum, along with a full panel of B vitamins.

What Does the Research Say About Probiotics for Calves?

The research is promising but mixed. Probiotics show benefits for intake and growth on average, but results depend heavily on the product, the strains, the dose, and how the trial was run.

The most complete recent look is a 2025 meta-analysis in the Journal of Dairy Science that pooled 55 studies (56 trials) on dairy calves. The authors found that probiotic supplementation improved total dry matter intake, starter intake, and average daily gain, while feed efficiency did not differ from untreated calves. Results also varied by type: Lactobacillus and Bacillus products increased daily gain, while some other types showed no significant difference. The authors were clear that differences between studies were large, so the results should be read carefully.

A 2023 scoping review in the same journal, covering 110 controlled trials, found just how different those trials were. According to that scoping review , supplementation ran anywhere from 1 day to 462 days, and daily doses ranged from about 4 million to 370 billion CFU per calf.

The practical takeaway: a probiotic is not a guarantee, and one product's results do not transfer to another. Look for a product that names its strains and guarantees a count, and judge it on how your calves do.

One Dose at Birth or Daily Dosing: Which Probiotic Approach Fits?

Both approaches are in use, and the research does not name a winner. The better choice is the one that fits how your calves are raised and how reliably your crew can give it.

The two approaches work differently:

One dose at birth. A paste like Start Baby is given once, in the first hours of life, while the gut is still being colonized. Start Baby's label calls for one full tube within six hours of birth. It is a single step that fits into the same visit as the first colostrum feeding, and there is nothing to remember at later feedings.
Daily dosing. Other products, often powders mixed into milk or milk replacer, are fed every day for weeks. They keep adding organisms over a longer stretch, but they depend on someone adding the right amount at every feeding. This difference in approach is a big reason the trials in the research reviews ran anywhere from 1 day to 462 days.

A few questions can help you decide. Who feeds your calves, and how consistent is that routine? Are calves on milk replacer, whole milk, or nursing their dams? Do you want a step that happens once at calving, or one built into every feeding? Whichever approach you choose, follow the label directions for that product, and ask your veterinarian how it fits your calf health plan.

A probiotic fits around colostrum, not in place of it. For where a probiotic belongs in the full first-day routine, including colostrum amounts and timing, see our guide to newborn calf care in the first 24 hours . Our FAQ page answers common questions about Start Baby dosing.

How Do You Read a Calf Probiotic Label?

Start with the guaranteed analysis, then the strain names, then the directions. A good label tells you exactly how many live organisms you are paying for and what they are.

Three things to watch for when comparing products:

A number with a unit. "Contains probiotics" tells you nothing. A minimum CFU count per dose lets you compare.
Named strains. Since results vary by organism type, you want to know which organisms you are getting.
Directions that fit your routine. The best product is one your crew will actually give on time, every time.

Can Probiotics Replace Colostrum, Electrolytes, or Antibiotics?

No. A probiotic is a supplement that works alongside good calf care. It does not replace colostrum, it does not replace electrolytes for a scouring calf, and it is not a treatment for a sick calf.

Colostrum provides the antibodies a newborn needs, and nothing in a probiotic tube can stand in for it. For a calf that is already scouring, Penn State Extension's guidance on electrolytes for dairy calves is to choose an oral rehydration product based on its electrolyte content, not on whether it contains microbials. And any calf that is weak, off feed, or getting worse needs your veterinarian.

Start Baby contains no antibiotics or hormones. If a calf does need treatment, that plan belongs with your vet.

Frequently Asked Questions About Calf Probiotics

Put a Probiotic Into Your Day-One Routine

If you want a probiotic in your calf program, the simplest way is one tube at birth, given at the same visit as colostrum. Shop Start Baby in 5, 25, or 50 packs , or call us at (223) 341-9188 to talk through how it fits your calving routine.

Newborn Calf Care: What to Do in the First 24 Hours

Tue, 22 Sep 2026 23:38:09 GMT

The first 24 hours decide a lot about a calf's health. In order, the essentials are: make sure the calf is breathing, dip the navel, feed 4 quarts of clean, high-quality colostrum within the first hour or two, move the calf to clean, dry bedding, and set a consistent milk schedule. Here is how to handle each step.

We are a Lancaster County, Pennsylvania farm family, and we put this checklist together from Penn State Extension and University of Minnesota Extension guidance. It works for dairy calves and, with a few adjustments for calves nursing their dams, for beef calves too.

What Should You Do Right After a Calf Is Born?

Check that the calf is breathing well, then dip the navel and get the calf onto clean, dry bedding. Those three things happen in the first minutes, before the first feeding.

The navel is an open door for bacteria in the first hours of life. Penn State Extension recommends dipping rather than spraying, because a dip reaches all the way to the belly wall. The classic product is 7% tincture of iodine, and research has also backed alternatives such as 2% chlorhexidine. A simple tip from the same source: use a small disposable paper cup for each calf, so a dirty dip cup never spreads infection from one calf to the next. Skip teat dip. It is made to keep skin soft, and a navel dip is made to dry the cord out.

Dipping is only part of navel care. A calf that lies in wet, dirty bedding still picks up a heavy dose of germs, so clean bedding in the calving pen and the calf pen matters just as much. Deep straw also adds warmth in cold weather.

How Much Colostrum Does a Newborn Calf Need, and How Fast?

A large-breed calf needs 4 quarts of clean, high-quality colostrum within the first hour of life, or 2 quarts in the first hour and 2 more within 6 to 8 hours. Small-breed calves such as Jerseys can get 3 quarts in the first hour. Those are the guidelines from Penn State Extension .

Timing matters because a calf's gut can only absorb antibodies for a short window. Penn State reports that within 6 hours, the gut's ability to absorb antibodies drops by about a third, and by 24 hours it absorbs less than 10 percent of what it could at birth. After that window closes, no amount of colostrum makes up the difference.

Quality matters as much as volume. Penn State notes that a Brix refractometer reading of 22 percent or higher indicates high-quality colostrum. Feed or chill colostrum quickly after milking, and keep equipment clean, since bacteria in colostrum can interfere with how many antibodies the calf absorbs.

Do not count on nursing alone. Penn State reports that about 40 percent of calves left to nurse on their own do not drink enough colostrum. For beef calves on the cow, watch to confirm the calf has nursed well, and have a bottle or tube feeder ready if it has not.

When Should You Give a Newborn Calf a Probiotic Supplement?

If you use a probiotic supplement , the first hours are the time to give it. Our Start Baby calf probiotic paste is labeled for one full tube within six hours of birth. Each tube carries a guaranteed minimum of 60 billion CFU of beneficial bacteria plus B vitamins, and it contains no antibiotics or hormones.

What Does a Newborn Calf Feeding Schedule Look Like After Colostrum?

After colostrum, most calves move to two milk or milk replacer feedings a day, sized to birth weight. Penn State Extension's general guideline is whole milk at 10 percent of birth weight per day, or milk replacer at 12 percent.

One pint of milk weighs about a pound, which is how the quarts are figured. Increase amounts gradually if you want faster growth, and feed more during cold or stressful stretches, especially for calves under three weeks old.

Consistency is as important as the amount. The University of Minnesota Extension advises feeding milk at body temperature (101 to 102.5°F) and on a regular schedule, and weighing milk replacer powder rather than measuring it by volume. Milk replacer mixed too strong can cause scours on its own. Offer fresh water from the first days as well, since water is what lets the rumen start developing.

What If a Newborn Calf Won't Drink?

A calf that is too weak to suckle can be fed with an esophageal feeder (tube feeder), and Penn State Extension notes that calves absorb colostrum antibodies about as well from a tube as from a bottle. The key is doing it gently and correctly.

Penn State's steps, in short:

Measure the tube from the tip of the calf's nose to its elbow (about 20 inches for most Holstein calves) and mark it.
Lubricate the tube by dipping it in the colostrum.
Pass the tube slowly over the back of the tongue as the calf swallows.
Confirm you can feel the tube in the esophagus before any liquid goes in.
Let the liquid drain slowly at body temperature, then remove the tube slowly and clean it.

If you have never tube-fed a calf, ask your veterinarian to show you before calving season. A calf that cannot stand, will not swallow, or seems cold and flat needs a call to your vet right away.

What Should You Watch for in the First Few Days?

Watch the navel, the manure, and the calf's attitude at feeding time. Those three checks catch most problems early.

Penn State Extension recommends checking each calf's navel twice by 10 to 14 days of age. By one week old, the navel should be about the size of your thumb. Swelling, a thick or foul-smelling discharge, or a calf that kicks when the navel is touched can all point to infection.

For manure, normal calf manure is loose, about like pudding or yogurt, and sits on top of the bedding. Watery manure that runs through the bedding is scours , and a scouring calf can dehydrate quickly. A calf that suddenly needs coaxing to finish its bottle deserves a closer look that same day.

Frequently Asked Questions About Newborn Calf Care

Get Your Day-One Supplies Ready Before the Next Calf Arrives

The best first day starts before the calf is born: navel dip and cups, a clean bottle and tube feeder, a colostrum plan, and your supplements on the shelf. Stock your calving pen with Start Baby in 5, 25, or 50 packs so the first tube is ready when you need it, or call us at (223) 341-9188 with questions about your calf program.

Calf Scours in Newborn Calves: Causes, Early Signs, and When to Call Your Vet

Mon, 14 Sep 2026 22:01:45 GMT

Anyone who has raised calves knows the feeling. You walk the hutches in the morning, and one calf is slow to get up, its ears are down, and the bedding behind it is wet. Scours is one of the biggest threats to young calves, and it moves fast. The earlier you spot it, and the more ready your plan is, the better that calf's chances.

This guide covers what calf scours is, what causes it, how to tell normal calf manure from scours, how to judge dehydration, and when a calf needs your veterinarian. We wrote it from the perspective of a dairy family here in Lancaster County, Pennsylvania, but the same basics apply to dairy and beef calves anywhere.

What Are Calf Scours?

Scours is diarrhea in young calves. It matters because of what comes with it: a scouring calf loses water and electrolytes quickly, and dehydration is what makes these calves so sick. According to the University of Minnesota Extension , scours is the leading cause of death in calves under one month of age, and dehydration is what kills them.

Most cases show up in the first three weeks of life. Penn State Extension notes that calves with infectious scours usually start showing signs between one and three weeks of age. That is the window when the protection a calf gets from colostrum is fading and its own immune system is still catching up.

What Causes Scours in Calves?

Scours has two broad sources, and many sick calves have more than one going on at once.

Infectious Causes

Viruses, bacteria, and parasites all cause scours. The University of Minnesota Extension reports that rotavirus, coronavirus, and Cryptosporidium ("crypto") cause about 95 percent of infectious scours cases in calves under three weeks old. E. coli and Salmonella are also common culprits on some farms.

Every calf is exposed to these pathogens. Whether a calf actually gets sick often comes down to how big a dose it picks up from its surroundings, and how well its defenses were set up in the first hours of life.

Nutritional and Management Causes

Not every case starts with a germ. Common management triggers include:

Not enough milk. A calf needs energy to grow and to fight off disease at the same time. Underfeeding is one of the most common causes of scours.
Inconsistent feeding. Changing feeding times, milk temperature, or how milk replacer is mixed stresses the calf's gut.
Milk replacer mixed too strong. Over-concentrated replacer pulls water into the gut and causes diarrhea on its own.
Stress. Transport, weather swings, dehorning, and switching milk sources can all bring on short-term scours.

Nutritional scours often clears once the stress is removed, but it can still dehydrate a young calf just as quickly as an infection, so these calves need close watching too.

Normal Calf Poop vs. Scours: How to Tell the Difference

A calf on an all-milk diet should not have firm manure. Loose manure alone is not scours.

Normal: semi-formed to loose, about the consistency of pudding or yogurt, and it sits on top of the straw bedding.
Scours: close to the consistency of water, and it runs right through the bedding.

Penn State Extension suggests scoring manure on a simple scale, where a "1" is pudding-like, a "2" is yogurt-like, and a "3" (roughly maple syrup, loose to watery with a strong odor) counts as scours. Scoring every calf the same way helps your whole crew make the same call.

Color gets a lot of attention, but the University of Minnesota Extension points out that manure color usually has little diagnostic value unless there is blood in it. Blood in the manure is a reason to call your vet.

Early Signs a Calf Is Getting Sick

The best time to catch scours is before the calf stops eating. Watch for:

Droopy ears, dull eyes, and a calf that seems depressed or slow
A calf still lying down when the others are up
A calf that needs coaxing to finish its bottle or bucket
Faster, harder breathing (make sure you are not mistaking scours for pneumonia)
Sunken eyes and dry gums

Attitude at feeding time is one of the most reliable early clues. A calf that normally drives into its bottle and suddenly needs encouragement deserves a closer look that day.

How to Check a Calf for Dehydration

Because dehydration drives how sick a scouring calf gets, it helps to judge it quickly. Penn State Extension reports that a scouring calf can lose 5 to 10 percent of its body weight in water within a single day.

Two quick checks tell you a lot:

Skin tent test. Pinch a fold of skin on the neck and count how long it takes to flatten. Under 2 seconds is normal. Two to 6 seconds suggests moderate dehydration. Over 6 seconds suggests severe dehydration.
Gums. Healthy gums are pink and damp. White, dry gums point to significant dehydration.

Per Penn State Extension, fluid loss beyond about 8 percent usually calls for IV fluids, which means a call to your veterinarian.

What to Give a Calf With Scours

Treatment decisions belong with your veterinarian, and every farm should have a written scours protocol worked out with them. A few principles show up in nearly every extension recommendation:

Electrolytes come first. Oral electrolytes replace the water and salts the calf is losing. Mix them exactly as the label directs, because a solution mixed too strong can make scours worse.
Keep feeding milk. Both Penn State and Minnesota Extension advise against pulling milk from a scouring calf. Electrolytes cannot supply enough energy on their own, and the calf needs that energy to recover. Feed electrolytes as separate feedings in addition to milk.
Antibiotics are not automatic. Since most scours cases are caused by viruses or crypto, antibiotics will not treat the cause in most calves. Your vet will usually decide based on a rectal temperature and an exam.
Pain relief helps. Scours is uncomfortable, and your vet can recommend an anti-inflammatory that helps a calf get back on its feet.

When to Call Your Veterinarian Right Away

Call your vet for any calf that cannot stand, will not suckle, has blood in its manure, has a temperature above 102.5°F or below 101°F, or is showing signs of severe dehydration. Those calves may need IV fluids that only your vet can provide.

How to Lower the Risk of Scours From Day One

Prevention works better than treatment, and most of it happens in the first hours of a calf's life.

Colostrum, early and plenty. The University of Minnesota Extension recommends 4 quarts of clean, high-quality colostrum within the first two hours of life. A calf's ability to absorb antibodies drops every hour after birth
A clean calving pen. Exposure starts the moment the calf hits the ground. Clean, dry bedding lowers the dose of pathogens a newborn picks up.
Clean everything the calf can reach. Bottles, buckets, nipples, and hutches should be cleaned and disinfected between calves.
Consistent, adequate milk. Same time, same temperature, same mix, every feeding.
A cow vaccination plan. Work with your vet on pre-calving vaccines that improve the protective antibodies in colostrum.

Some producers also add a direct-fed microbial at birth as part of the day-one routine. That is where our product fits. Start Baby is a probiotic paste with a guaranteed minimum of 60 billion CFU per tube and a full panel of B vitamins, given as one tube within six hours of birth. It supports the gut in those first hours. It does not replace colostrum, clean housing, or your veterinarian's protocol, and it is not a treatment for a calf that is already sick.

If you are setting up a day-one routine for your calving season, the Start Baby 25 Pack is sized for steady year-round calving, and our FAQ page covers timing and dosing questions.

Keep a box of Start Baby in the calving pen so the first tube is ready when the next calf arrives. Shop Start Baby or call us at (223) 341-9188 .

Frequently Asked Questions About Calf Scours

Build a Scours Plan Before You Need It

Most people who raise calves deal with scours at some point. The calves that come through best usually belong to operations that already have colostrum, cleanliness, feeding consistency, and a vet-approved treatment plan in place before calving season starts. Write your plan down, make sure everyone on the crew knows it, and keep electrolytes and your day-one supplies stocked.

Questions about fitting Start Baby into your calf program? You can read more about our family and how Start Baby started, or call our team at (223) 341-9188 .