Fatigued animals a concern for producers

Muscle trauma, fatigue can cause animals to be unable to stand or walk after transport to slaughter plants

MANHATTAN, Kan. — The livestock industry is starting to pay more attention to the issue of fatigued animals arriving at slaughter plants.

“Mobility of cattle at slaughter facilities has gained a lot of focus over the last few years,” said Jacob Hagenmaier, a veterinarian and PhD candidate at Kansas State University.

Some have suggested over-use of beta agonists because cattle were showing up with sloughed off hooves and some had to be euthanized, he said at the International Beef Welfare Symposium held June 8-10 in Manhattan, Kansas.

As a result, zilpaterol, which Merck sells under the brand name Zilmax, was suspended from markets in the United States and Canada in 2013.

Guy Loneragen from Texas A & M University linked thousands of feedlot deaths to the product, although the manufacturer rejected his claims.

However, while beta agonists are suspected, there are also other factors.


The hog industry faced fatigued pig syndrome from 1992-2000 with a steady increase in transport losses in hogs. They suffered no obvious trauma or disease but refused to stand or walk. Tests on heavily muscled hogs displaying fatigue showed blood abnormalities and increased respiratory rates.

It was suspected cattle were suffering from the same syndrome, and research that started in 2014 is investigating connections.

Researchers tested ractopamine but found aggressive handling had a major impact on cattle.

“Aggressive handling increased stress hormones and caused acute metabolic acidosis,” he said.

Metabolic acidosis happens when energy demands are high and depletes oxygen. Earlier studies found potassium levels can increase 40 percent, which affects the heart.


“It doesn’t take much before we really start altering the physiology of the animal,” he said.

Cattle are not athletes. They should be moved slowly and should not have to trot. They have 30 percent lung capacity of a horse but a greater oxygen requirement.

Muscle trauma and fatigue may also be linked to transportation. Cattle that are ready for shipping may be left standing in a trailer or on concrete for hours at a time. They may also be subjected to extreme weather.

“We are only at the tip of the iceberg with fatigued cattle syndrome. There is still so much to learn,” Hagenmaier said.

A 2009 paper from Colorado State University researcher Temple Grandin outlined factors connected to fatigued hog syndrome:

  • Rough handling of pigs and excessive electric prod use can increase the number of downers.
  • Overloaded trucks can contribute to downers.
  • Poor leg conformation, especially among lean hybrid pigs, may be to blame. Genetic changes for better foot and leg structure have improved problems such as collapsed ankles, post leggedness and straight hooves. Pigs with good legs and feet are less likely to be lame.
  • Indiscriminate use of ractopamine (Paylean) contributed to fatigued pig syndrome.
  • Porcine stress syndrome is a genetic condition that contributes to downer and death losses. However, Grandin said there are differences between a PSS pig and a fatigued one. A PSS pig is not able to walk and will quiver and rapidly grunt with an open mouth. A fatigued pig lies down and is cool to the touch. They appear to have no energy but after some rest may be willing to move.


  • Denise

    You would think after all this time these guys would know the best way to handle and care for pigs. And you wonder why more and more young people are not eating meat. I haven’t eaten pork,myself, for over a decade.
    These animals live a life of misery from the minute they are separated from their mothers to the moment they die.
    Unfortunately, these factory animals are handled by people who couldn’t care less about them. It’s just a job.And the owners only care about easiest and cheapest way to make a buck. It does not speak well for our society, as a whole, when we don’t care enough to treat our animals humanely We’re on a downhill slide.

    • farmer-to-be

      Denise unless you have personally worked on multiple hog operations and have witnessed this “misery” for yourself then please do not comment with propaganda. You wouldn’t want me to say that you don’t care about your children at all and they are just hobby for you because I witnessed one of them crying because that is what you are doing on many articles. If you wish to make a comment please make it an informed one by educating yourself with all the facts from every side of the situation. Thank you

      • Denise

        Then why the article? Of course, not all hog producers are careless with their animals. But what about the guys, at the other end , unloading them from the transport trailers into the slaughter plants? What about the sows who can hardly walk after being confined to gestation crates, travelling great distances or pigs fed too much ractopamine and lose their hooves? They can’t even get up let alone walk down the ramps to their final destination.
        Why the heading?:” Muscle trama ,fatigue can cause animals to be unable to stand or walk after transport to slaughter plants.”
        You may be one of the good guys but that doesn’t mean we should turn and look the other way when abuse is happening. Or not make sure they are not experiencing added misery by the impatient handlers in the slaught plants.
        Don’t you think your life would be filled with misery if you never felt the sun on your body or never got to do what is normal and healthy for your species?Pigs are not dumb. They are smarter than dogs.
        The younger population is looking at this and wondering what the hell are these guys thinking?
        When John Fefchak said some hog farmers, in Manitoba, are opening their barns to allow their hogs to be outside and making a good living ,that gave me hope that things can change for the better.

      • Harold

        Are children being taken to slaughter these days? I don’t see the connection. Was this an “informed” and “educating” factual “side of the situation?” [article] distortion is propaganda. I was looking for a informed, educational, factual side of your comment for your warrant to demand others to perform in same. Wired differently, I have what it takes to hear all comments no matter the frontier they originate. You could have served better by illustrating how the profile doesn’t match and what is done in your watch to prevent the concerns of the article content- that is of course, if you are entirely involved. Denice was reacting to an article of true animal sufferance. Was the article fiction? The article describes “misery” and are you it’s interpreter. Personally I see your comment as a method to bring dignity to a travesty. You are eating your own pigs- if the consumer is not your livelihood. For this, you owe the consumer/comments respect. Moreover, hog farmers specialize in one aspect- not in all things. The article points to this fact.