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Turning Beef Cows Out on Spring Pasture: What You Need to Know

Turning Beef Cows Out on Spring Pasture: What You Need to Know

Spring weather's unpredictability can have devastating effects on your cattle. Rapid changes in temperature and weather conditions pose a risk of serious health issues that can impact performance. From rain to even blizzards, these temperature swings can lead to several challenges.

In the spring, cows and calves are more susceptible to issues like grass tetany, foot rot, and parasite infestations. When these problems arise, cattle divert energy from growth and instead focus on repairing infections and activating their immune system.

How to Prevent Grass Tetany in Cattle

Grass tetany is caused by low blood magnesium in cattle. Grass tetany is often more common in the spring as cattle begin grazing on lush, immature forages that are high in potassium. High potassium levels can decrease the absorption of magnesium, causing low blood magnesium in cattle.

More prevalent in older cows, grass tetany often affects beef cows during early lactation. Aging decreases their ability to mobilize magnesium reserves from bone, unlike younger cows. This condition is also more likely to occur on cool, cloudy days with temperatures ranging between 40-60 F.

Symptoms of Grass Tetany in Cattle

Grass tetany symptoms include lack of coordination, salivation, excitability, and, in the final stages, tetany, convulsions and death. Grass tetany is occasionally encountered on meadow pastures, but the incidence is much lower than on small grains like wheat.

Wheat pasture poisoning is also a form of tetany caused by calcium deficiency in wheat pastures. Often thought to be a magnesium deficiency, wheat pasture poisoning is predominantly caused by deficient levels of calcium causing low blood calcium.

Prevention and Treatment of Grass Tetany

When tetany is suspected, always consult with your local veterinarian. Typical protocols for treatment include an IV injection of calcium-magnesium and a mineral supplement containing a high level of magnesium (10%) and calcium between (15-20%). For prevention, mineral containing highly available magnesium and calcium should be provided with a daily intake ranging from 2-4 ounces.

How to Control Flies on Cattle

Flies are more than just a nuisance in the spring, they cost the beef industry billions of dollars yearly. According to the Journal of Entomology, U.S. beef producers lose a staggering $1-2 billion annually due to flies alone.

The main culprits are horn flies, face flies and stable flies. These flies wreak havoc on cattle. Horn flies, in particular, can bite your cows up to 30 times daily. Meanwhile, stable flies are painful blood feeders that mainly target the front legs and cause irritation. While face flies may not bite, they are notorious for spreading diseases like pink eye and infectious bovine rhinotracheitis (IBR) among your herd.

How to Control Flies on Cattle

During the peak of summer, a single cow can host anywhere from 1,000 to 4,000 horn flies. In fact, it's estimated that each cow loses about 10 pounds of blood per summer due to these pesky insects. And watch out for stable flies too - just 4-6 of them per cow can have a significant economic impact.

Fly Control Methods for Cattle

Achieve fly control in cattle by reducing fly populations to levels below the economic threshold. Instead of 1,000-4,000 horn flies per cow, aim to keep flies at a maximum of 200 per cow using proven fly control methods.

Many fly control options are available today, such as ear tags, sprays, oilers, dust bags, vet guns and feed additives. Combining multiple tools may be necessary for effective fly control in beef production, due to the fact that resistance can occur.

Additionally, new methods of fly control, like adding garlic to your cattle mineral can be another proven strategy for keeping flies at bay.

How to Manage Cattle Parasites

Parasites pose a major threat to grazing animals. In forages that are less than 2-3 inches tall, parasites are more prevalent in the spring as the grass begins to grow and temperatures warm up.

According to Kansas State University, economic losses from internal parasites are estimated to cost the U.S. livestock industry over $3 billion annually. Parasites, also called internal nematodes, rob nutrients from the animal, reduce nutrient absorption and feed intake, and overstimulate the immune system.

Ostertagia, Trichostrongylus, Haemonchus, and Cooperia are the most common parasites. Infection occurs when parasitic eggs become L3 larvae. As eggs hatch and develop into L3 larvae, they wiggle, crawl up short grass blades and even live in water droplets. Cattle then graze the forage infected with the parasitic larvae and start the infestation.

After ingestion, L3 larvae go to the digestive tract where they latch onto the gut wall and rob cattle of nutrients. Parasites then produce eggs that pass through the animal in manure and the lifecycle starts all over again. Furthermore, parasites are hardy and can become inactive in the digestive tract if environmental conditions are too hot or too cold for survival. They become active again when conditions improve.

Lifecycle of Parasites in Cattle

Lifecyle of Parasites in Cattle

Source: MWI Animal Health

Symptoms of Parasites in Cattle

Parasite-infected cattle may exhibit a range of symptoms including reduced appetite, weight loss, diarrhea, coughing, and a deteriorated coat. The severity of these symptoms can vary based on the specific parasite species, potentially leading to dire consequences such as immobility or death if left untreated.

According to Texas A&M University, the clinical signs of parasites or wormy cattle include pale mucous membranes, bottle jaw, pot belly, diarrhea, not grazing, not chewing cud, rough and dry haircoat, thinness, weakness and inability to stand. These signs are similar to those caused by malnutrition and liver flukes.

Prevention and Treatment of Parasites in Cattle

Like fly control, any parasite program's goal is to maintain the economic threshold of the cow, not reach zero. Cattle will eventually build immunity to parasites, but younger calves with weaker immune systems are more susceptible.

Discussing deworming protocols with your veterinarian is critical. Every farm has different dewormer programs but developing a strategy can help avoid parasitic resistance. This means not every grazing animal requires dewormer every spring, every fall, or every six months.

Dewormers should be administered strategically to infected animals in order to reduce reinfection, parasite resistance and pasture infestation. Recent research also suggests essential oils can help manage parasites without developing resistance.

How to Prevent Foot Rot in Cattle

Foot rot in cattle is caused by the bacteria Fusobacterium necrophorum and results in lameness and swelling.

In the spring, cattle are subjected to mud and soft ground that weakens the structural integrity of hooves, which are made out of keratin similar to skin, hair and fingernails.

As spring weather makes hooves soft, they become more susceptible to tears and damage from rocks or hazards on the ground. Once the hoof is split, bacteria enter and the infection begins.

Symptoms of Foot Rot in Cattle

Foot rot is a common and highly contagious bacterial disease that affects cattle worldwide. The severity of foot rot can range from mild to severe, with the first symptoms usually being lameness, swelling and leg favoring. Affected cattle will often exhibit difficulty in walking, standing or moving around and may exhibit a reluctance to eat or drink.

As the disease progresses, more severe symptoms may emerge, including a strong and foul odor emanating from the affected area, separation of the claws and the formation of abscesses. These abscesses can cause significant pain and discomfort for the animal and may lead to a loss of appetite.

If left untreated, foot rot can cause permanent damage to the foot, making rehabilitation and cure nearly impossible. It can also lead to secondary infections and even be fatal, particularly in cases where the animal's immune system is weak. Due to the rapid spread and severity of the disease, it’s critical to detect it early and implement proper treatment measures, including antibiotics and good hygiene practices to prevent its spread.

Prevention and Treatment of Foot Rot in Cattle

Treating foot rot begins with your veterinarian. According to Oklahoma State University, veterinarians often prescribe antibiotics and anti-inflammatory products for pain relief to infected cattle with foot rot. If possible, infected animals should be kept in dry areas until healed.

Prevention of foot rot is multi-dimensional. It’s recommended to keep cattle in environments with minimal mud and manure. Additionally, using foot baths, mineral supplements with zinc and vaccinations can all help reduce incidences of foot rot.

Keeping Cattle Healthy with Ralco

At Ralco, we've been committed to the well-being and success of farmers and ranchers for over half a century. With our extensive range of high-quality minerals, essential oil feed additives and animal health products, we ensure the health and performance of your cattle, no matter what health challenges they may face this spring. Trust Ralco to keep your cows and calves thriving this year.

Check out Ralco's beef product line-up or send us an email at to learn more!


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