'Like a Grenade in an Ammunitions Depot'

Veterinarians Say Treating for Endotoxemia in Cattle With BRD As Important as Using Antibiotics

Endotoxemia, a condition that often develops in cattle with bovine respiratory disease (BRD), can be ‘like a grenade going off in an ammunitions depot,’ according to a Kansas veterinarian.

"It sets off a chain reaction that ultimately destroys the entire facility," says Dr. Roger B. Winter, a bovine veterinarian with Intervet/Schering-Plough Animal Health. "In cattle, the ‘explosions’ just go off at a slower pace. Treating for endotoxemia may be as important as providing antibiotics to combat the lung infection."

BRD, a bacterial lung infection often due to the pathogens Pasteurella multocida, Pasteurella haemolytica or Haemophilus somnus, remains a major economic problem in the cattle industry resulting in poor production, weight gain, feed conversion and, sometimes, death. In many cases, however, it’s not only the infection making the animal ill. Endotoxemia can also reduce performance and prevent a speedy recovery.

Endotoxemia occurs both as the animal’s immune system attacks bacteria and as antibiotics disrupt the ability of bacteria to repair themselves, Dr. Winter explains. As a result, bacteria break up and fall apart, releasing cell wall "chunks" that contain endotoxins. Endotoxins cause inflammation and tissue damage in the lungs.

"Endotoxemia is part of the overall disease complex in BRD," says Dr. James S. Cullor, director of the Veterinary Medicine Teaching and Research Center, Tulare, Calif.

"It’s just part of what’s making the animal with BRD sick. If we understand that, we can better diagnose, treat and, ultimately, prevent more serious illness and production losses."

Dr. Cullor, who has studied inflammation in cattle extensively, points out that some inflammation is good. "It helps stimulate the immune system.

"It’s the body’s way of saying ‘get going’," he says. "But after a certain point, inflammation causes a lot of trouble in the heart and lungs. The degree of trouble it causes varies among individual animals."

Signs of Illness

It’s hard to miss cattle with endotoxemia. "They’ll stop eating, act depressed and have a fever. Internally, a lot more is going on," Dr. Winter says. "What appears at first to be slight illness can progress rapidly to a severe, life-threatening situation."

The heart rate may be weak and rapid and the respiratory rate fast and shallow. Normally pink tissues, such as the nose or gums, will be dark and muddy, indicating a lack of oxygen. "Without intervention that prevents further tissue damage, the animal will collapse to the ground and be unable to get up," he says.

Minimizing Damage

Veterinarians agree that the best way to prevent the devastating results that can occur as a result of endotoxemia is to treat promptly.

"Get the infection under control as quickly as you can with antibiotics and good nursing care," Dr. Cullor says.

It is important to control the effects of endotoxemia with anti-inflammatory therapy. "The sooner it’s given, the better," he says.

Dr. Winter says, "Waiting too long to treat is like trying to fix the buildings in the ammunitions dump after they’ve been blown up. It’s better to prevent their destruction in the first place by limiting the initial damage the grenade caused."

"Anti-inflammatories cannot neutralize endotoxins, but they do help block their effects," he adds. "They inhibit an enzyme that produces pain and inflammation."

First-Hand Experience

Based on first-hand experience, Dr. Doug Ford of Beaver Creek Veterinary Clinic, Brush, Colo., says that stress reduction, vaccination and antibiotics are the first line of defense against BRD.

"We also need to treat for endotoxemia with an anti-inflammatory," he agrees. "An anti-inflammatory isn’t a silver bullet, but it is a useful tool. It can make animals with BRD feel better, so animals get back on feed. If cattle eat, they keep up their strength and will be better able to overcome BRD," Dr. Ford says.

Dr. Kelly Lechtenberg of Midwest Feedlot Services, Inc., Oakland, Neb., agrees. "By moderating the inflammatory response, we can potentially make the animal feel better and get back on feed faster, minimizing the effects of the disease," he says.

The type of anti-inflammatory used is important, he points out. "We want to select a non-steroidal anti-inflammatory that can reduce the inflammatory response without suppressing the ability of the animal to respond to infection, as steroids might," says the feedlot consultant.

But is using an anti-inflammatory cost-effective?

"A few trials have already shown there are economic benefits and more trials are underway," Dr. Winter says.

Dr. Ford says, "Using an anti-inflammatory has become more cost effective because the price of the only injectable nonsteroidal anti-inflammatory approved for use in cattle – Banamine (flunixin meglumine) Injectable Solution – has dropped. The savings come in reduced chronic cases, deaths and return to regular feed consumption."

Dr. Winter notes, "Treating promptly for endotoxemia can greatly reduce deaths and illness, which ultimately should improve the cattle producer’s bottom line."

Key Points

In BRD, the body's immune system and antibiotics cause bacteria to break up and release toxins.

The toxins cause inflammation and lung tissue damage, or endotoxemia.

Endotoxemia slows recovery and can result in life-threatening illness.

An anti-inflammatory can help reduce the effects of endotoxemia, reduce deaths and speed recovery.

Studies Show Banamine and Antibiotic Improve Outcome in Cattle With BRD

Studies show that Banamine (flunixin meglumine) Injectable Solution, the only nonsteroidal anti-inflammatory approved for use in cattle, can improve outcome and reduce production losses from BRD.

Banamine, marketed by Intervet/Schering-Plough Animal Health, is indicated for use in beef and non-lactating dairy cattle for control of fever associated with BRD and endotoxemia and for control of inflammation in endotoxemia.

In one study of beef cattle with BRD, 181 animals were treated with both Banamine and the antibiotic oxytetracycline and 182 received only the antibiotic. There were twice as many deaths in the antibiotic-only group, Dr. Winter says.

Banamine also reduced fever significantly within 24 hours and improved respiration. In the Banamine treatment group, improvement occurred in over 60% of animals after only one treatment with Banamine plus the antibiotic. Impressive results also were obtained in a similar study of dairy calves with BRD, he says.

Banamine has been shown to reduce lung lesions associated with BRD, which are associated with reduced weight gain, he says.

Banamine has also been used widely and successfully for treatment of BRD in Europe for more than 10 years, and in the United States has been used for over 13 years in horses for alleviating pain and inflammation due to musculoskeletal disorders and intestinal pain associated with colic. The safety of the product is well-demonstrated, Dr. Winter says.

Banamine is a prescription product that is administered to cattle by slow intravenous injection. The recommended dose is 1 to 2 ml/cwt given either once daily or divided into two doses given 12 hours apart for up to three days.