August 2019 - Equine Nutrition
With so many supplements and grain options, how should you know what to feed? Join us this month as our expert, Dr. Alison Cornwall answers your questions concerning equine nutrition.
Click here to read this month's questions and answers.
- I have a 19-year-old APHA used for hunter/jumper and has developed minor arthritis of the hocks the past year or so. At first, we did injections (hock and stifle) semi-annually but a friend of mine suggested shoes to try to lengthen the time between injections. It’s been about 5 months now so we are coming up to his injection date. Will the shoes actually help to keep him comfortable enough to extend to annual injections? And after two rotations of semi-annual injections, is it too hopeful of me to think we might be able to switch to annual? (View Answer)
Are your horse's stifles being injected based on stifle pain and radiographic changes? If not, It will be best to focus on his hock issues. Low heels can worsen both hock and stifle problems, so it is wise to trim and shoe hind feet according to radiographs the first time, followed by regular trimming/shoeing to maintain the correct angles. Systemic joint therapies such as oral glucosamine/hyaluronic acid, and intramuscular Adequan given either as a pulsed dose of 7 injections repeated every 3-4 months, or as a single injection given every 3 weeks are often effective for joint pain, have been shown to slow the progression of arthritis, and are less invasive than joint injections. A two to three-week period is needed to see maximum effect of both of these treatments. A regular exercise program to keep your horse fit and supple is also helpful. Lastly, joint injections should be performed based on assessed need as determined by lameness evaluation, rather than administered on a preset schedule. The type of medication used for joint injection, if needed, has an effect on duration of response. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC
- Without a definitive diagnosis, what is the best way to proceed with a horse that was lame due to heel pain? I had a full lameness examination performed with radiographs of both front feet. The 10-year-old paint mare was lame on her front left (suspected heel pain). The x-rays were not definitive as to the cause but her left hoof showed mild to moderate sclerosis of the distal border of the navicular bone. It was written as "Suspect bone cyst along the flexor surface of the navicular bone." She has adequate medial to lateral balance. She has been shod with a 2-3 degree wedged pad and is now sound. She is also on a daily dose of oral Equioxx. I plan to keep her shod while trying to get enough heel growth to provide her with the correct natural angle for her conformation. Do you have reccomendations on how to proceed so as to maintain a sound horse? (View Answer)
Based on your description of the radiographs and your mare’s response to the 2-3 degree wedge pad, it is likely that she has inflammation of the navicular bursa/deep digital flexor tendon and/or impar ligament desmitis. Raising her heels decreases tension on these structures and reduces pressure on the navicular bone flexor surface. If a veterinarian is available locally who can perform diagnostic ultrasound through the frog, you can have those structures evaluated. The other imaging modality for these structures is MRI. If soft tissue imaging can’t be performed, the alternative is to carefully observe your mare for any recurrent lameness. You did not mention if she has returned to regular work. If so, you may want to try to wean her off Equioxx by giving it only on ridden exercise days, then only on hard exercise days, then stop administration and observe her. A 15-minute minimum ridden walk warm up prior to faster work will allow her tendons and ligaments to pre-stretch and will increase viscosity of her navicular bursa fluid to allow her optimum exercise comfort and safety. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC
- My 15-year-old Thoroughbred gelding has been sore on and off for 3 weeks. The equine chiropractor diagnosed a stifle injury. She recommended turnout, cold hosing and exercises. My gelding is reluctant to fully extend the hurt leg and his gait is shorter and is lame at the trot though nothing to notice at a walk. My local veterinarian says this is above his knowledge. He did suggest stall rest and bute. My gelding lives out 14-7 and did not improve after 3 months so I am trying stall rest. What do you suggest? There is mild swelling on the outside of the stifle joint. (View Answer)
Without radiographs and ultrasound, it is not possible to determine if your gelding’s stifle injury has primarily a bony or a soft tissue component, or both, and how extensive the damage may be. The most effective course of action will be to take him to a facility where imaging is available so that you can proceed with knowledge of his actual injury, the most effective treatment options, and the prognosis with treatment.
You can treat for pain and inflammation with a 10-14 day course of phenylbutasone or Equioxx, cold hosing for 15 minutes twice daily, and stall rest with hand walking for 20 minutes twice daily to determine if this course of action will be helpful. Soft tissue injuries require 8 months of confinement and gradually increasing controlled exercise, again, based on sequential imaging, to heal. Arthritic changes of the stifle will benefit most from systemic and/or local therapy and regular light exercise. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC
- My large pony is currently taking a series of three sound shock therapy sessions for a torn tendon. It is an old injury that was misdiagnosed initially. What are the tendencies to re-injure her leg once it has healed? (View Answer)
Three factors will determine re-injury rate.
1) The tendon must be completely healed clinically and on ultrasound exam following strict criteria before she returns to her job (by the end of walk, trot, canter on the flat during rehab.)
2) The discovery and appropriate treatment of any other issues that she may have to prevent soreness elsewhere causing overload of the limb that is currently injured.
3) Maintenance of a long term fitness program for your pony. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC
- My 19-year-old mare was recently diagnosed as having an arthritic knee. Radiographs were done and after reviewing the xrays the knee was clean. After a flexion test, she demonstrated moderate lameness. On hard ground, the walk seems normal however, at the trot, she is lame. Could this be a soft tissue issue? (View Answer)
Diagnostic local anesthesia can be performed to determine if the lameness originates from the proximal cannon area, the knee itself or above the knee. Radiographs and ultrasound can then be used to determine soft tissue versus bone/cartilage issues. When you have this information, the best treatment options can be used. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC
- I have a 12-year-old Quarter horse gelding and for six weeks he has been lame on the back left (4 out of 5 scale). Unfortunately, I have no history on this horse. Our first veterinarian performed three nerve blocks and said she saw improvement with the third block. Radiographs showed nothing. I had a second veterinarian out to perform an ultrasound. They thought there was swelling at the fetlock and thought the problem was in the lower limb. However, neither vet could make a diagnosis due to nothing showing on the radiographs and ultrasound other than some fusion but said that should not cause the severe lameness. Both veterinarians are stumped and the horse is now on stall rest with hand walking 10 minutes a day, 3x a day. Not sure what to do next. He was tripping on his front feet but were told to roll his toes. Any advice? (View Answer)
I am assuming that the third block was above your horse’s sesamoids, which would in general remove pain from foot, pastern and fetlock structures. Three likely causes for Grade 4/5 (severe) lameness are fracture, severe soft tissue injury and foot abscess. You may want to have radiographs repeated, since stress fractures may take some time to become apparent. If the effusion was in the fetlock, collateral ligament injury would be suspect. Since your vet ruled out tendon/ligament injury, there may be a foot abscess that is taking a long time to come to the surface. Often ones that take this long break out of the coronary band rather than the sole. I would continue stall rest and hand walk 3 times per day and observe the foot for heat, pulse or a soft spot at the coronary band. Carol Gillis DVM, Ph.D., DACVSMR, Aiken, SC