Finding sick animals in the herd starts with building trust
Published on Feb. 22, 2020
“As cattle producers, we have to understand cattle and where they fall in the predator/prey relationship, they are always the prey,” said Iowa State University Head of Animal Science and Veterinarian Dr. Dan Thomson on a recent episode of Doc Talk.
Thomson explained as long as cattle view their handlers as predators, they are less likely to exhibit clinical signs of illness or lameness because herds will often abandon weaker cattle and weaker cattle are the first targets to predators.
“It is vitally important we domesticate and spend time with our cattle and calves,” he said. “Just going and standing by the water tank is a great acclimation exercise.”
He continued, “We have to get cattle to trust us and realize we aren’t a predator so they will more openly show us clinical signs of illness.”
He noted cattle will often try to mask signs so as not to appear weak and be attacked first. Once we have trust, then we can start trying to find the root of the issues.
“One of the first signs of sickness for me is anorexia, or when an animal stops eating,” said Thomson. “When an animal is sore or lame, the first thing they will do is decrease food intake.”
He continued, “It may be mild at first, but eventually we will begin to see a sunken flank and side and the calf will go from being full to being hollow-looking and that is a sign we should take a look.”
Another thing Thomson recommends is looking for any animals who are off by themselves.
“A lot of times sick or lame animals will seclude themselves from the rest of the herd,” he said.
He noted sick animals will also have a “dull” look about them.
“Animals should be alert and responsive to things such as the feed truck or us entering the pen,” Thomson said. “If they have a dull look in their eyes and drooping ears, it’s a good indication something is wrong.”
He noted with little calves, dropped ears can be an early sign of mycoplasma.
“We also need to look at their eyes, lips and nose for signs of dehydration,” he said. “Dry, cracked lips and sunken eyes are a good indication of dehydration and dehydration is a good indication of infection.”
“For cattle sick with respiratory issues, we say they have DART, or, depression, anorexia, respiration and temperature,” he explained. “On respirations, if the noise comes when they breathe in, that means the infection is in the upper respiratory tract. Noises coming from exhalation mean the infection is in the lower tract.”
“Another thing I look for is lameness,” Thomson said. “If I go in the pen and a cow doesn’t get up, they usually have a sore foot or some other type of lameness.”
He explained minor lameness usually results in a shortening of the animal’s stride.
“When an animal has a normal stride, the back foot will replace exactly where the front foot was,” he explained. “When an animal is lame, the stride will be shortened and either the front or back foot won’t come up as far as it should.”
He noted the second sign of lameness is a head bob.
“The old saying is ‘down with the sound,’ meaning the sound foot will go down at the same time as the head,” he said. “The worst type of lameness is three-legged lame, meaning they are putting no pressure on the hurt foot.”
“Ninety-percent of lameness is in the foot and until we examine the foot, there is no way of knowing exactly what the issue is, unless of course the stifle is swollen or the bone is clearly broken,” Thomson said. “There is no way of knowing whether it’s an infection or an abscess until we get the cattle in the chute and examine them close up.”
In the chute
“When we start thinking about going to get animals from the pasture to the chute, its critical we take our time and don’t exert them anymore than we have to,” Thomson explained. “Sick animals will tend to be flighty and we need to be careful as we bring them up for closer examination in the chute.”
“The sooner we can bring animals in for an examination, the better,” he stressed. “The longer wait to treat things, the worse they get.”
He noted it’s very important to document why we are bringing cattle up for examination, as it is impossible to see if they are lame in a chute.
“In any case, we want to start with taking the rectal temperature of the animal in question,” he said. “Normal rectal temperature should be between 101.5 and 103.5 degrees Fahrenheit. Above that is a fever and below is considered hypothermia.”
In lameness cases, its vital to physically pick the foot up and look at it.
“If there is no infection between the toes, we can rule out foot rot,” he said. “If there is a strawberry-like lesion on the heel, its likely hairy heel warts.”
Both foot rot and hairy heel warts are highly infectious. Foot rot is seen more in the winter, it is anaerobic and generally very smelly. Hairy heel warts are also highly infectious.
Thomson said once we rule out foot rot and hairy heel warts, its time to look for an abscess, which are caused by stone bruising or a split in the hoof.
“Once we rule out viral infections like hairy heel warts and foot rot, we should take trimmers and go around the hoof looking for abscesses. When we find the sore spot, the animal will pull away,” he said. “Similar to blood blisters under human fingernails, abscesses are pin-pointed and very distinct.”
Callie Hanson is the managing editor of the Wyoming Livestock Roundup. Send comments on this article to firstname.lastname@example.org.