Until last year, I’d only ever had one encounter with shipping fever. When I was a kid, a big draft mare arrived at our farm with a cough. My Dad told me she had shipping fever. The mare spent two weeks isolated in a makeshift box stall in the heated workshop, coughing and sputtering mucus. She got better, just as my Dad said she would, and---to a kid like me, at least---it didn’t seem like such a big deal.
Now I know better. In late spring of 2015, my Quarter Horse gelding, Page Martin Parker, came down with a case of shipping fever after I made a series of misguided decisions while traveling home from an event. He quickly developed pleuropneumonia that nearly killed him. He needed weeks of care, including hospitalization and dozens of invasive procedures, to bring him back from the brink, followed by several more months of rest and recuperation.
It was a very big deal. Here’s how it happened.
Storms on the horizon
The drive to Kansas had been uneventful. A friend had invited me to bring Parker along with her and her horse to a multi-day National Versatility Ranch Horse Association (NVRHA) event. It was a 17-hour drive from our home in Minnesota, but we stopped halfway through the trip to unload the horses and let them eat, drink and graze for a bit before continuing. We spent a total of eight days in Kansas. NVRHA events combine a clinic with four performance classes similar to trail classes, reining patterns and working cattle. It’s hard work, but Parker was in great physical shape and did wonderfully.
It wasn’t until the trip home that things went bad. We had originally planned to leave immediately after the award ceremony, but a huge storm system rolled in, and blowing dust severely reduced visibility on the roads. We decided to stay one more night and leave in the morning, taking a more northerly route to avoid a line of thunderstorms. This decision would add a few hours to our trip, but at the time, that didn’t seem like a big issue. We rolled out at 5:30 a.m. on May 12.
We made several stops the first day, and at each we offered hay and water to the horses and checked the temperature in the trailer. We had the option of staying overnight just on the eastern edge of Nebraska, but we worried about a fast-moving storm headed our direction. Rather than risk the possibility of being stuck waiting out a snowstorm, we decided to keep moving. So, after 16 hours on the road, we arrived in Minnesota and stopped for the evening. We had only two hours of driving ahead of us, but we were exhausted and needed to sleep.
We unloaded the horses and walked and hand-grazed them before tying them to a highline---a rope strung above eye level between two trees---for the night with their hay and water. The horses had plenty of experience with this setup, and we would be sleeping in the trailer only a few feet away.
I’d been asleep for only about an hour when I awoke and felt an urge to check on the horses. Parker was acting strangely. He was systematically bouncing his head downward as hard as he could before reaching the end of the rope. At first I suspected he might be colicking. I took his vital signs, and other than a slightly elevated respiration rate they were normal. I walked him, added a warmer blanket and offered him more water. He drank some, and then he ate a little more hay.
As soon as we arrived home the next day, I called my veterinarian, Martha Pott, DVM, who came out right away. By now Parker had a fever of 103 and he was beginning to cough. A clear case of shipping fever, Pott told me.
Shipping fever, she explained, is a respiratory infection that can develop when a horse is trailered over long distances with his head tied. Trailer interiors are often dusty, and the airborne contaminants can include large numbers of disease-causing bacteria. When the bacteria are inhaled and accumulate in the horse’s lower airways, and he is unable to drop his head to clear them out, the pathogens take root and multiply quickly. This, combined with an immune system challenged by the stress of being on the road, means that serious lung infections can set in within 12 to 24 hours.
Suddenly, I regretted the decision to stay on the road so long on the first leg of our journey and then to tie the horses to the highline overnight.
Pott prescribed two weeks of antibiotics and Banamine0, along with rest, yet Parker didn’t get much better. I took his temperature twice a day, and it sometimes ran as high as 105. He had no nasal drainage and coughed only once or twice a day, usually after trying to eat.
When Pott came back for a recheck, she found that Parker was anemic and his white cell count was very low. She changed his antibiotics to doxycycline, and for a few days Parker seemed to perk up---he was more interested in eating, and his temperature was headed toward the normal range. I thought we were over the worst. But he relapsed, and each day he seemed to get more lethargic.
Then, when I went out to feed Parker on the morning of Saturday, June 22, he gave me “that look.” He was very, very ill, and I knew if I didn’t do something quickly, he would die.
Pott’s clinic is closed on the weekends, so I loaded Parker and headed to the nearest referral clinic: Stillwater Equine Clinic in Stillwater, Minnesota. We were met there by Terry Arnesen, DVM, who listened carefully as I described what we’d been dealing with and the treatments we had tried.
After the standard physical exam, Arnesen brought out an ultrasound machine and placed the probe over Parker’s ribs. Within seconds, he was pointing out to me the amount of fluid surrounding my horse’s lungs, in the space called the pleural cavity. This space is typically like a deflated balloon, he explained, holding only a few teaspoons of lubricating fluid to allow the lungs to move freely as the horse breathes.
When a horse is fighting an infection, however, inflammation draws white blood cells to accumulate at the site, and fluid builds up. When the infection and excess fluids are limited to the interior of the lungs, it’s called pneumonia. Pleuritis is the inflammation of the tissues that line the lungs and chest cavity, and when a serious infection affects both the interior of the lungs and the pleural cavity, it’s called pleuropneumonia. What causes a respiratory infection to develop into pneumonia or pleuropneumonia isn’t fully understood---but long-distance transportation is one of the predisposing factors.
As more and more fluid collects, pressure builds, making it difficult for the horse’s lungs to expand so he can breathe. Eventually, Arnesen explained, the bacteria within the fluid can enter the bloodstream, causing a serious and potentially fatal systemic infection. He also told me that horses with cases as advanced as Parker’s usually have a dire prognosis, and some owners in my position might opt for euthanasia.
Here I was, standing next to this fantastic horse, who was alert and watching everything going on around him. Then he looked straight at me with his big black eyes through his long blond forelock---and the idea of simply saying goodbye and walking away just seemed impossible. I stammered and struggled to regain my composure and asked what some other options would be.
Arnesen said that he could insert tubes into each side of Parker’s chest to drain the fluid, which would relieve the pressure and remove some of the accumulated bacteria, lowering the risk of systemic infection. This might give his body a better chance to fight off the infection that was causing the fluid to build in the first place. Arnesen also said it might not work, but I knew we had to try.
I watched as the veterinary techs prepped Parker, then Arnesen made a small incision about two inches above and three inches behind my horse’s elbow. He then inserted a metal tube called a trochar, through which a flexible tube had been threaded.
He did the right side first. With a push, the trochar entered the pleural space, and almost immediately yellowish fluid began to pour through the drain into a bucket. By the time it was over, nearly four-and-a-half gallons of fluid had flowed out of Parker’s chest. Then Arnesen repeated the procedure on the left side, which yielded “only” a little over two gallons of fluid.
I was amazed. It was like my horse had been drowning from the inside. Once the flow abated, Arnesen capped the chest tubes with valves to prevent air from getting into Parker’s chest, then he taped the tubes securely to Parker’s body and wrapped the ends with bandages to absorb fluid that would continue to drain. Parker would remain like this, at the clinic, until his condition improved---or until the situation became hopeless.
Waiting and watching
The first 24 hours were tough, for everyone. Parker was started on two very strong intravenous antibiotics, which Arnesen told me could be stressful to organs like the kidneys. But, considering how sick my horse was, waiting for the results of the culture to tell us what kind of bacteria we were dealing with really wasn’t an option. Fortunately, Parker’s liver did fine until the test revealed that only one, much safer, antibiotic was needed.
I went to the clinic daily to brush and massage Parker. I took him for short walks outside in the sun, and he’d pick grass with his teeth but then let it fall out of his mouth. The walking seemed to make the drains more drippy, which was fine by me because I wanted to get that fluid out of him any way I could. Every other day the tubes were removed and cleaned, then put back in. Overall, Parker seemed lethargic, and he still wasn’t very interested in eating or drinking.
On the fifth day, Parker developed explosive diarrhea. Arnesen told me that it wasn’t an uncommon reaction to the stress of illness and hospitalization combined with numerous medications. Parker was started on an anti-diarrheal supplement and ulcer medication. He was already hooked up to continuous intravenous fluids, so dehydration wasn’t an immediate risk, but still we worried.
The next morning, I walked into the clinic and saw one of the veterinary technicians sitting in Parker’s open stall door on an overturned bucket. My heart leaped into my throat until I saw my horse on his feet. The tech had been there all night giving him fluids and cleaning him up after each round of diarrhea. It had been touch-and-go for a while, but she told me that Parker seemed to be doing better and had even eaten a bit and drunk a little water.
I began to notice improvement as well. Each day, Parker was more interested in the grass, and he was actually eating some. His diarrhea cleared up, and he was less lethargic. His fever broke and didn’t return. Someone suggested I try some aromatherapy with him. I’m not sure if it helped Parker, but I think the lavender scent helped settle my own nerves. Two weeks after we arrived at the clinic, Parker was well enough to have his drain tubes removed, be switched to oral antibiotics and come home.
But a full recovery was still far from assured. Three times a week I took Parker back to the clinic, and Arnesen used the ultrasound to find pockets of fluid in the pleural cavities. Each time, he inserted a tube called a teat cannula to pump the fluid out. With each visit, scar tissue was making it harder and harder to re-insert the cannula, and yet, after our sixth time, the amount of fluid we were getting was still increasing, not decreasing. Arnesen suggested that Parker be readmitted to the hospital so the big drain tubes could be put back in. Financially and emotionally, that wasn’t an option. With little else to try, Arnesen offered another option: He could inject a bit of liquid penicillin back into the pleural cavity after each draining.
The fact that Parker stood completely still while all of these holes were poked in him amazed me. Not once in this whole process did we have to give him any sedatives, even as he regained his strength.
Finally, on our 12th return visit to the clinic, Arnesen declared the treatment a success. He could still see one small pocket of fluid, but it was lower down in the chest, too close to the heart to insert a cannula safely. However, Arnesen thought Parker’s body would be able to clear the remaining fluid with just the help of antibiotics, which we would continue for another week. Parker would still need many months of rest before I could ride him again, and whether he’d ever be able to reach the level of activity we’d once enjoyed wasn’t clear. But he would live.
As I left the clinic that day, Arnesen told me that he normally sees three or four cases of pleuritis each year, yet he’d already seen five so far that year, and it was only July. Of those five, only two had survived---Parker had been one of them, even though his case was by far the most critical. Arnesen said he’d never seen a horse survive if he had to draw more than two gallons from his chest. Parker had had more than six gallons drained.
Words of warning
After my experiences with Parker, I began to hear of other cases of shipping fever. I met one woman who had returned from a trail ride and brought her horse directly to the veterinarian because she thought he had a lameness issue. The horse was stumbling on the trail and just seemed like he “didn’t feel good.” The horse had been trailered six hours, then tied to a highline overnight. The signs appeared the next day. The woman was surprised to find out the “lameness” was actually shipping fever. I was sorry to hear that the horse died within the first 24 hours, after a little over two gallons of fluid were drained from his lungs.
While I was still contending with Parker’s illness, a friend of mine returned from a trail ride out West with a group of seasoned riders who have spent many years trailering their horses. When she arrived home after the 20-hour drive, she could not get her little mare to unload---the horse just stood with her head down and would not move. She had shipping fever. After nearly three months of antibiotic treatment, the mare did survive, but unfortunately her lungs have so much scar tissue that she can no longer be ridden on trail rides.
When I tell people what happened to Parker, I usually get one of two reactions. If the person knows about the dangers of shipping fever, they try hard not to tell me how stupid I was to travel so far with a very large horse who could not get his head down to clear his airway of the bacteria that builds up inside the trailer.
More frequently, however, the reaction I get is total disbelief that a horse could get sick from riding in a trailer. People will tell me they have hauled horses from Texas to Seattle to Minnesota and back and never had any problems with shipping fever. I always reply, sincerely, that I hope they never do. But I do urge them to look into the recommendations for helping to keep a horse’s airways healthy on long trips.
I’m happy to report that Parker made a full recovery. He has full lung capacity and has returned to his previous fit and athletic self, and we are once again participating in strenuous ranch versatility events. Even though I’m extremely careful with how I ship now, we had a slight scare when he developed a cough shortly after we returned from a trip. After phone consultation, I drove to Pott’s clinic immediately to pick up antibiotics. Fortunately, the cough disappeared quickly. Perhaps it wasn’t a respiratory problem at all, but I’m not about to take chances. I know what shipping fever is now, and I never want to deal with it again.
This article first appeared in EQUUS issue #466, July 2016.