Antibiotics
 

I belong to a partnership that races on the east coast. Our horse last ran on Oct 22 and finished up the track. An after race scope showed mucous in the airway so immediate treatment with antibiotics ensued. I don't know the exact antibiotic that was used.

The horse is entered to run back on Saturday, a mere 10 days after the treatments were started.

The manager claims the antibiotics cleared everything up so we're ready to go!!

In my past infrequent experiences with my horses getting antibiotics, I can't recall any of them being able to run within 10 days of starting on antibiotics. It seems to me that we typically had to wait 7 days after the treatments ended and typically, the horse was treated for at least a week if not a little longer, which would put a race out at least 14 to 17 days upon the start of antibiotic treatment.

Do I have my timeframes out of whack here?

Cannon can answer this better, but my experience has been when our horses were on anti-biotics they barely galloped, let alone worked or run. It seems like it was closer to a 30 day time line before racing again vs 10 days.

Never had one on antibiotics run back sooner than 3 weeks.

I think we've got the proverbial "smoke blown up our arse" by the manager, then.

Won't be the first time and I'm sure it won't be the last - unfortunately.....

It all depends on what kind of infection and the severity of the infection. Some horses we've had can have a minor infection that can be treated with mild antibiotics and some you can scope and have a lot of mucus and they require stronger treatment protocol. Sometimes you can have a horse that has a minor, undectected infection that has no symptoms but runs poorly and sometimes these type of infection will cause a horse to bled. It all depends of what kind of infection, type of antibiotics and the horse. Some need more time than others.

But once any antibiotic treatment has begun, even for the mildest of minor infections, what is the timeframe for the antibiotics to clear a horse's system?

Are there antibiotics that would clear within a few days if the horse was only treated for a day or two?

usually i find any horse after antibiotics is flat as a pancake i tend to give them a weeks spell then back in work for the two weeks before they run

First of all most antibiotics take more than a few days to work. More than likely they are treating this horse with an antibiotic called baytril which can be given 5-7 days. Then yes of course you would want the horse to have some time after that for the horse to build up their immune system. It is all up to what the trainer and owner feel is the best for the horse. When we run a horse we usually scope them two works before they run to make sure they are clean and sometimes it can be as simple as a cycle of antibiotics and they are fine for the race.

Again I am saying up front that I am limited by my zero patient base of the horse variety but thousands of humans treated albeit with reasonable success.

1) The "lag" your seeing is more a need to recover from the illness itself and not necessarily the antibiotic. Like any human who has pneumonia for example ....in order to get back in the gym or to run the distance you would normally work out at.....there is a period of rehabilitation from the weakness of the illness but not induced by the treatment of say a week of Levaquin.

2) Many times physicians stop antibiotics started in humans after a couple days when a) the suspected infection is more likely viral by clinical acumen as a couple days pass

b) the drugs seem like overkill for the illness which has improved more likely having run it's course

c) Very few antibiotic courses are that short(1-2 days) that treat to cure an infection in humans. Exceptions would be things like high dose flagyl for vaginal trichomonas which is given as a single dose (sorry for thos eating as they read this) or perioperative antibiotics given as prophalaxis for procedures.

It is more likely the horse didn't have an indication in the first place for antimicrobial care so having stopped them in a short period should do no harm because it didn't really help in the first place. The poor performance one sees is more likely due to a setback in aerobic performance with the illness.

Just the human perspective for what it is worth!!

if you only used antibiotics for a day or two you likely got no benefit from the drugs.... it's the same as human medicine, just because symptoms ease doesn't mean an infection is cleared.
Seems like maybe they just dosed the horse arbitrarily and then took it off to meet a 7 day withdrawal time on whatever medication they gave it.

it's funny how often horses are prescribed Baytril when Bayer specifically says it should not be given to horses, especially young horses. It can help enormously but there has been some information (without formal, objective studies) indicating it damages cartilage and can contribute to other joint abnormalities. It should really only be used in mature animals when other antibiotics won't work.

Is there a suggested or recommended time-frame after the treatment is given to avoid a positive piss test? Or, more importantly, do any antibiotics cause a positive if you race the horse too soon?

It just seems I've been told, or read somewhere, that it takes "x" days for an antibiotic to clear a horses system to avoid a positive test.

Interesting horses aren't supposed to use Baytril, I didn't know that. But not uncommon to use some meds especially wormers for animals not prescribed for use...ie panacur, Ivomec. I think people have taken to using Baytril regularly as it is injectible.

But like you said, I am under the impression Baytril is a last resort anitbiotic, that it is classified so to say as a super antibiotic, so regular use of Baytril could render it ineffective when really needed. I rarely use Baytril and have tried to caution others that use it regularly that when they need it might not work. Also doesn't sound good to use antibiotics for a few days, just to me would render use of antibiotics when needed fairly ineffective.
Clavamox is an excellent broad spectrum fairly powerful antibiotic, don't know if that can be used on horses.

As far as I know antibiotics START to clear the system around 48 hours but it takes up to 5 to 7 days to completely be out of the system. Don't know anything about how it would compromise a test, but I'm sure it could.

I don't post often---I mostly lurk, however I work for a racetrack vet, and have for more than 4 years, and I can't even count on one hand the number of horses that have been sick just in the last WEEK that went on antibiotics.

If it's just a touch of mucus or you're not in a huge hurry to get a horse to the races, you may choose to put your horse on Gentocin. If it's something severe, you would typically put your horse on Baytril. The typical dose on either drug is anywhere from 5-7 days depending on the severity of the infection in the horse.

We take care of one trainer that scopes EVERY horse after EVERY work (the owners get billed for 2 scopes max a month, not including post race scopes, which are always billed for) so that we can catch anything a horse may have as early as we can. If the horses are dirty, then we will put them on one of three drugs (Gentocin, Baytril, or Uniprim powder) depending on how far out a horse is from a race and the severity. If the horse is running off of the work (i.e. Not going to work again before the race, or won't be scoped again before the race) we will almost always put them on injectable anti-biotics.. We've gone as few as 4 days out (which to be perfectly honest, we don't really like, because you can't have them 100% in that time frame) but we ALWAYS will stop an antibiotic treatment no less than 48 hours out, to allow the semi-slump to have a bit of time to occur before raceday. I haven't noticed a big decrease in the placings of the horses that get it 48 hours before they run, as opposed to their last dose being 5-7 days out.

I read above something about they were just trying to stop whatever it was to make the 7 day withdrawl time, which doesn't exist. You CAN give antibiotics the day before and be perfectly safe from a testing standpoint. You may have a duller horse for giving it the day before, but it CAN be done. The only exceptions I know of are Pennicillin Procaine (which anything ending in -caine you can pretty much say you're looking at at LEAST 7 days if not more). Pottasium Penn is the only other big exception, but I can't say for sure it's because it cannot be given, as much as you'll mave a duller horse if you give it too close to a race or work.

As for the Baytril shouldn't be given to horses statement. Baytril is perfectly safe in horses. It is even listed in the equine drug book that one of my bosses carries in her truck. I get bored and I read it. In horses you use the Baytril 100. There are plenty of drugs/medications that are not specifically labelled for horses that have plenty of use for them. Some are labelled "For Use in Dogs" or are even labelled for human use.

In my (non-vet school educated) opinion, running a horse 10 days after beginning treatment is not dooming your horse to running a bad race. We had a runner just the other day that spent 5 days on Gentocin, and won at Churchill, and we had a filly come down from Delaware, FULL of mucus that we put on Baytril for 5 days and got beat a nostril 48 hours after her last dose.

Thanks that was very informative.

Yep - completely agree - great info from everyone!!! Thanks!!!!!