Enterotoxemia presents serious threat to calves unless promptly treated
Some cattle producers experience frustrating cases of acute enterotoxemia in calves, caused by bacterial toxins. The bacterial infection proliferates rapidly and produces toxins that damage the gut.
If this condition is not treated quickly and reversed, toxins get into the bloodstream. Then, the calf goes into shock and dies within a few hours. The calf may be healthy in the evening and dead the next morning – or healthy in the morning and going into shock by afternoon.
The term enterotoxemia simply means toxemia – or bacterial toxins in the bloodstream – from bacteria found in the intestine. This condition is fatal unless the animal is treated immediately.
The most common type of enterotoxemia in calves is caused by Clostridium perfringens, one of the Clostridia species normally found in the gastrointestinal (GI) tract of livestock and passed in the feces.
These bacteria rarely cause gut infections in adult animals but can cause fatal disease in calves when conditions are just right within the gut to enable them to proliferate rapidly.
There are several types of C. perfringens, which can affect calves of different ages, in different ways.
The types of C. perfringens that cause can disease in cattle include A, B, C, D and E.
Types B and C often cause disease in young lambs, calves, goats, pigs and foals, while type D generally causes disease in older calves.
Dr. J. Glenn Songer of the Department of Veterinary Microbiology and Preventative Medicine at Iowa State University says the most common cause in nursing age calves, traditionally, is type C.
“Type D, which causes infections we often term over-eating disease in sheep – and is the same as ‘pulpy kidney’, can also occur in calves but is not as common as in sheep,” he explains. “Today, with vaccination of cattle against type C and D, we see relatively few type C and D infections in calves.”
Yet a surprising number of producers fail to vaccinate, so some infections – particularly type C, still occur, he says.
“In our typing of isolates today, more than 90 percent are type A – and this type is not included in typical clostridial vaccines. The next most common would be type C, with between four and five percent, and then type D,” he says.
“In calves with hemorrhagic enteritis and sudden death, however, type E can also be a problem,” Songer continues. “If we limit what we are evaluating regarding causes of perfringens-associated enteritis to calves with hemorrhagic abomasitis and sudden death, we find about 10 percent of those deaths are from type E infections,” he says.
There are no vaccines that include type E.
“This illustrates the need for diagnostic work, more than just a post-mortem, if we want to find out how to prevent these infections,” Songer emphasizes. “We need a bacteriologic culture.”
Once the bacteria is cultured, it can be genotyped so the veterinarian and producer know exactly what they are dealing with.
“The best way to prevent acute toxic gut infections in young calves caused by Clostridium perfringens is to vaccinate the dam,” says Robert Callan of Colorado State University. “Then, the antibodies will be in the GI tract as soon as the newborn calf nurses, to neutralize the toxin.”
“When we vaccinate calves at birth, it takes 10 to 14 days to develop peak antibody levels and strong immunity and maybe longer, since two doses of vaccine are often necessary,” he says.
Vaccinating the calves can be beneficial, however, in herds that experience the worst problems in older calves.
“The C. perfringens type C and D antitoxin can also be helpful, especially in young calves born to dams that have not been vaccinated,” he says.
Some ranchers routinely give antitoxin at birth to calves if they know the dam was not vaccinated or if they purchased the cow and don’t know her vaccination history. Alternatively, they may give antitoxin to any calf that develops symptoms of disease if they can find the calf before it dies.
“The vaccines are very effective, especially against C. perfringens types C and D,” he says.
Herds vaccinated with a seven-way or eight-way clostridial vaccine (rarely experience these problems, Callan adds.
“But, we still see some herds with calves dying of a disease, which people often refer to as enterotoxemia or purple gut disease,” he continues, noting that signs of illness are the same, but eight-way vaccine or C and D antitoxin are less effective at preventing this one.
Callan comments, “When we look at these diseases in beef calves today, probably the majority are now caused by C. perfringens type A. When we culture intestinal contents of beef calves with signs of enterotoxemia, there is often very high growth of C. perfringens type A and not C or D.”
Heather Smith Thomas is a correspondent for the Wyoming Livestock Roundup. Send comments on this article to firstname.lastname@example.org.