Re:bloated seahorse

Dear Lynn:

I’m very sorry to hear about the problems with positive buoyancy your bloated male has developed. Please correct me if I’m mistaken, but when you say that your stallion has a bloated stomach, I assume that you mean that his brood pouch, which is situated at the base of his tail right where the abdomen and the prehensile tail merge together in the front, has become swollen and enlarged.

Positive buoyancy in a male seahorse is most often due to gas building up within its brood pouch, which becomes swollen and buoyant as a result, but it can also be due to an overinflated swim bladder in some cases, and the concern is that the problem will worsen until the seahorse is floating at the surface of the aquarium unable to swim or feed.

As in many other bony fishes, the seahorse’s gas bladder functions as a swim bladder, providing the lift needed to give them neutral buoyancy. In essence, the swim bladder is a gas-filled bag used to regulate buoyancy. Because the seahorse’s armor-plated body is quite heavy, this organ is large in Hippocampus and extends well down into the body cavity along the dorsal boundary.

When the swimbladder is inflated with just the right amount of gas, the buoyancy provided by this gasbag exactly cancels out the pull of gravity, and the seahorse will neither tend to float nor tend to sink. This condition is known as neutral buoyancy, and it makes it very easy for the seahorse to swim and maneuver almost effortlessly. But when the swimbladder is over inflated with gas, the seahorse will have positive buoyancy and must exert a lot of energy when swimming in order to counteract the tendency to float. And if the swimbladder is underinflated, the seahorse has negative buoyancy and must swim hard in order to avoid sinking.

The first indication of a problem with positive buoyancy is a loss of equilibrium. The seahorse’s center of gravity shifts as excess gas accumulates in brood pouch or its swim bladder, and it will have increasing difficulty swimming and maintaining its normal posture, especially if it encounters any current. It will become apparent that the seahorse has to work hard to stay submerged, as it is forced to abandon its usual upright swimming posture and swim with its body tilted forward or even horizontally in order to use its dorsal fin to counteract the tendency to rise. If untreated, the problem can worsen until the hapless seahorse is left bobbing helplessly at the top of the tank.

There is an easy way to determine whether positive buoyancy in a male seahorse is due to gas accumulating in its brood pouch or is the result of an overinflated swim bladder, Lynn. If the stallion’s brood pouchis bloated or enlarged, then you can be sure that the problem is due to a buildup of gas in the seahorse’s pouch (or marsupium, as it is also known). If the male’s pouch does not appear to be swollen or inflated, yet it is floating nonetheless, then the positive buoyancy is almost certainly do to a hyperinflated swimbladder, or gas bladder, as it is also known.

Since your stallion has had this problem for so long, I would recommend releasing the gas that is trapped in his pouch and then treating the seahorse with Diamox (the tablet form of acetazolamide). If successful, evacuating the air that has built up in his pouch will provide your seahorse with immediate relief from the positive buoyancy, and the Diamox treatments will help prevent this problem from recurring.

Perhaps the most effective way to release the gas is to carefully insert a small catheter or cannula or tiny pipette into the aperture of the pouch, and then apply firm but gentle pressure to the outside of the pouch. This usually causes the air to escape through the catheter or pipette, providing the affected seahorse with immediate relief. (We will discuss a number of other methods for evacuating the gas from a bloated brood pouch later in this e-mail, Lynn, so that one way or another we can make sure that you release the pressure.)

Once the brood pouch has been emptied of gas, relieving the problem with positive buoyancy, you should treat your stallion with acetazolamide (brand name Diamox) in order to prevent further problems with gas bubble syndrome.

Acetazolamide can either be administered orally by injecting a solution
made from Diamox (the tablet form of acetazolamide) into feeder
shrimp or the tablets can be used to administer acetazolamide as a
series of baths instead. Subcutaneous emphysema or tail bubbles often respond
well to these alternative methods of treatment as well, as explained below:

If the seahorse is still eating, you can also administer the acetazolamide orally, which will allow you to treat the affected seahorse in the main tank amidst familiar surroundings and in the company of its tankmates where it is the most comfortable. You get the acetazolamide into the food by preparing a solution of the medication, as described below, and then injecting it into live feeder shrimp or even the large Piscine Energetics frozen Mysis relicta. The medication is deactivated fairly quickly once you prepare the solution for injecting, so you must prepare a new acetazolamide solution each day during the treatment period. Here’s how to proceed:

Administering Diamox (i.e., acetazolamide) Orally

I have found that acetazolamide is often more effective when it’s ingested and administering the medication orally allows you to treat the seahorse in the main tank where he’s most comfortable and relaxed.

If you can obtain a small syringe with a fine needle, the acetazolamide solution can simply be injected into feeder shrimp or even frozen Mysis. Mic Payne (Seahorse Sanctuary) used this method of administering acetazolamide successfully when he had recurring problems with GBD due to maintaining a population of Hippocampus subelongatus in shallow tanks only 16-inches (40 cm) deep:

"Seahorses maintained in this system are susceptible to gas bubble disease. Specimens with bubbles around the eyes or under the epidermis of the tail are readily treated with acetazolamide (Diamox tablets 250 mg). Mix a very small amount of crushed tablet with water and inject it into several glass shrimp that are then frozen. These are then fed to the target animal at the rate of two per day for four days. Bubbles disappear on the second day."

Hawaiian volcano shrimp or red feeder shrimp (Halocaridina rubra) work great for this. If a fine enough needle is used, they will survive a short while after being injected — long enough for their twitching and leg movements to attract the interest of the seahorse and trigger a feeding response.

Leslie Leddo reports that a 1/2 cc insulin syringe with a 26-gauge needle was ideal for injecting frozen Mysis or live red feeder shrimp. They plump up when injected and ~1/2 cc is about the most of the solution they can hold. There bodies will actually swell slightly as they are slowly injected and excess solution may start to leak out. The 26-gauge needle is fine enough that it does not kill the feeder shrimp outright; they survive long enough for the kicking of their legs and twitching to assure that they will be eaten.

If your male is no longer eating, Lynn, then you will need to administer the Diamox in a hospital tank as a series of baths instead:

Acetazolamide Baths

The recommended dosage is 250 mg of acetazolamide per 10 gallons with a 100% water change daily, after which the treatment tank is retreated with the sole light at the dosage indicated above (Dr. Martin Belli, pers. com.). Continue these daily treatments and water changes for up to 7-10 days for best results (Dr. Martin Belli, pers. com.).

The acetazolamide baths should be administered in a hospital ward or quarantine tank. Acetazolamide does not appear to adversely affect biofiltration or invertebrates, but it should not be used in the main tank because it could be harmful to inhibit the enzymatic activity of healthy seahorses.

Using the tablet form of acetazolamide (250 mg), crush the required amount to a very fine powder and dissolve it thoroughly in a cup or two of saltwater. There will usually be a slight residue that will not dissolve in saltwater at the normal alkaline pH (8.0-8.4) of seawater (Warland, 2002). That’s perfectly normal. Just add the solution to your hospital tank, minus the residue, of course, at the recommended dosage:

Place the affected seahorse in the treatment tank as soon as first dose of medication has been added. After 24 hours, perform a 100% water change in the hospital tank using premixed water that you’ve carefully aerated and adjusted to be same temperature, pH and salinity. Add a second dose of newly mixed acetazolamide at the same dosage and reintroduce the ailing seahorse to the treatment tank. After a further 24 hours, do another 100% water change and repeat the entire procedure until a total of up to 7-10 treatments have been given. About 24 hours after the final dose of acetazolamide has been added to the newly changed saltwater, the medication will have lost its effectiveness and the patient can be returned directly to the main seahorse tank to speed its recovery along.

One of the side affects of acetazolamide baths is loss of appetite. Try to keep the affected seahorse eating by plying it with its favorite live foods during and after treatment, until it has fully recovered.

The seahorse usually show improvement of the tail bubbles within three days. Dr. Martin Belli reports they nearly 100% success rate when this treatment regimen is followed for 7-10 days, and most cases clear up in less than a week.

Okay, Lynn, here are some instructions explaining a number of different methods for evacuating the air from your male’s pouch. If you can release the air that’s building up within his pouch, that should provide him with some immediate relief and allow you time to obtain some Diamox and complete his treatments.

Pouch Massage: Burping the Pouch

Pouch bloat is ordinarily easily resolved by evacuating the gas from the marsupium. This procedure is commonly known as pouch massage or "burping" the pouch and it provides immediate relief for the seahorse when successful. The first attempt or two at performing this procedure can be very intimidating, I know, but it is actually much easier than it sounds.

To expel the trapped air, wet your hands first and hold the seahorse upright in the water with your non-dominant hand, allowing his tail to wrap your little finger or ring finger so he has a good grip and feels secure (Burns, 2001). While the seahorse is thus restrained, use your dominant hand to massage the pouch firmly yet gently between your index finger and thumb, working upward with a circular motion from the bottom of the tail toward the top so as to work the trapped gas upwards toward the opening of the pouch (Burns, 2001). Don’t squeeze the pouch too forcibly, just maintain gentle pressure from below as you massage the pouch, always working from the base of the pouch toward the orifice at the top with your thumb and index finger to force the gas upward.

Hopefully, as your massage moves to the upper half of the pouch and approaches the top, the aperture of the pouch will begin to gape open, allowing a stream of bubbles to escape (Burns, 2001). This is the "burp" you’ve been hoping to produce, and when it happens, you can actually feel the bloated pouch slowly deflate as you gently force the bubbles out (Burns, 2001).

If that does not happen, however, you will have to modify your gas evacuation technique somewhat, this time using the thumb and index finger of your non-dominant hand to massage the pouch with a gentle back and forth motion, while you use a bobby pin or similar blunt implement in your dominant hand to carefully tease open the aperture of the pouch (Burns, 2001).

You are not trying to insert the bobby pin into the pouch at all (Burns, 2001). The idea is to use the rubber-coated end of the pin to gently manipulate the orifice of the pouch, using a sideways pressure on the mouth of the pouch to tease it open, rather than using a downward pressure to force the bobby pin into the opening (Burns, 2001).

Begin as before, holding the seahorse upright in the water with your non-dominant hand, allowing his tail to wrap your little finger or ring finger so he has a good grip and feels secure, while leaving your thumb and index finger free to perform the massage (Burns, 2001). Begin at the base of the pouch near the tail, and massage the pouch gently but firmly between your thumb and index finger, working upwards with a back and forth motion as though gently squeezing a toothpaste tube from the bottom to the top (Burns, 2001).

Meanwhile, using your dominant hand, position one of rubber coated ends of the booby pin at the mouth of the slitlike aperture, and use sideways pressure to prise the lips of the pouch open without actually inserting the pin into the pouch (Burns, 2001). This may take a surprising amount of pressure, so proceed gently but firmly, making sure you direct the brunt of the pressure sideways rather than downward (Burns, 2001). As your massage progresses to the upward portion of the pouch, a few small bubbles at a time will be expelled, and you can feel the pouch gradually deflate between your fingers.

Continue applying pressure from the bottom of the pouch up while prizing the mouth of the pouch open until the pouch feels flaccid and no more gas escapes (Burns, 2001). You may have to repeat this procedure two or three times to be sure you have evacuated all of the trapped gas (Burns, 2001).

If successful, it’s an instant cure and your seahorse should be back to normal immediately, able to swim freely and feed as usual. Burping the pouch is stressful, but seahorses are very forgiving and often will swim away and start eating immediately afterward as though nothing happened. This type of pouch gas is not a serious problem and poses no threat to the seahorse’s long-term health.

Eyedropper Pouch Evacuations

Rather than burping or massaging the pouch, some hobbyists find it easier to use an ordinary eyedropper to evacuate the air from a large seahorse’s pouch. This technique is fairly self-explanatory. Get a glass eyedropper (the smaller the better) from your drugstore — the glass kind that has a rubber bulb. The glass tip is much smoother than plastic droppers are and the rubber squeeze-bulb allows you to apply suction using the eyedropper with one hand while holding the seahorse with your other hand.

Take the seahorse in your nondominant hand, keeping it underwater, of course, and let it wrap its tail round your baby finger. Then take the eyedropper in your dominant hand, squeeze the rubber bulb and hold the bulb squeezed closed while you very gently insert the glass tip into the aperture of the pouch. Once you are just slightly inside the pouch, slowly release the squeeze bulb and the bubbles of trapped air will often be aspirated.

Remove the eyedropper, expel the bubbles it extracted, and repeat the whole procedure as necessary to remove all the trapped air and restore neutral buoyancy.

If you have a Pouch Kit from Ocean Rider, the flushing apparatus can be used in a similar manner to aspirate the trapped air.

Needle Aspirations.

It is also very practical to aspirate air from a bloated pouch using a small hypodermic needle and a syringe. The pouch can easily be penetrated from side and is not harmed by the entrance of the needle. It causes the seahorse surprisingly little discomfort and is often less traumatic that massaging the pouch and other methods for evacuating gas. It is a quick and effective technique and is often easier on the seahorse keeper and his patient than other approaches.

However, like repeatedly massaging or burping the pouch, needle aspirations can be irritating and harmful to the pouch if they must be performed over and over again. If aspirating the air from the pouch does not cure the problem, and the gas continues to build up and cause buoyancy problems for your seahorse, then you’ll need to attempt flushing out the pouch thoroughly and/or treating the stallion with Diamox instead in order to resolve the problem once and for all.

Whatever method you decide to use to evacuate the male’s pouch, be sure to observe the following precautions when manipulating seahorses:

Handling Seahorses

I do not like to use an aquarium net to transfer or manipulate seahorses, since their delicate fins and snouts can become entangled in the netting all too easily. I much prefer to transfer the seahorses by hand. Simply wet your hand and fingers (to avoid removing any of the seahorse’s protective slime coat) and scoop the seahorses in your hand. Allow them to curl their tail around your fingers and carefully cup their bodies in your hand to support them while you lift them out of the water. When you gently immerse your hand in the destination tank, the seahorse will release its grip and swim away as though nothing out of the ordinary has happened.

Composed of solid muscle and endowed with extraordinary skeletal support, the prehensile tail is amazingly strong. Indeed, large specimens have a grip like an anaconda, and when a 12-inch ingens or abdominalis wraps its tail around your hand and tightens its hold, its vise-like grip is powerful enough to leave you counting your fingers afterwards!

In fact, it can be quite difficult to remove an attached seahorse from its holdfast without injuring it in the process. Never attempt to forcibly detach a seahorse from its hitching post! When it feels threatened, it’s instinct is to clamp down and hold on all the tighter. When you must dislodge a seahorse from its resting place for any reason, it’s best to use the tickle technique instead. Gently tickling the underside of the tail where it’s wrapped around the object will usually induce the seahorse to release its grip (Abbott, 2003). They don’t seem to like that at all, and will quickly let go to move away to another spot. Once they are swimming, they are easy to handle.

In your case, Lynn, if you have the necessary apparatus on hand, it might be better for you to perform a thorough pouch flush right away, since that method of releasing the trapped air is often more effective in preventing a recurrence of the problem. Here are detailed instructions from Leslie Leddo, myself, and other experienced seahorse keepers explaining different ways to perform a pouch flush:

"Pouch Flush Techniques and Tips"
By Leslie Leddo

You will need:

•A small syringe. I like to use a 1-cc syringe.

•A catheter of some sort. It needs to be something that is plastic, very narrow, cannulated, blunt tipped, semi pliable, but not so soft that it bends from just a bit of pressure, on one end and fits snugly on to the tip of a syringe at the opposite end. Some suggestions would include an a plastic intravenous catheter, with the center introducer needle used to puncture the skin and vein order to introduce the catheter removed, a plastic pipette, or the syringe tips that come inside some of the aquarium test kits. If you have access to an IV catheter any size, between an 18 and 25g will work well.

•A bowl. I like to use something with a wide rim so I have space to move freely and have enough room should I need another pair of hands…i.e., an assistant. The syringe and pipette/catheter are both used to flush the pouch as well as to aspirate the previous days flush from the pouch.

How to prepare the Syringe and Catheter:

Draw about 1cc of the medicated flush solution into the syringe by pulling back on the plunger.

Invert the syringe so the tip is pointed up. With the syringe inverted, gently tap it until all the air bubbles come to the surface just below the syringe tip; with the syringe still inverted depress the plunger until all the air is removed from the syringe and a small amount of the solution is emerging from the syringe tip.

Attach the catheter or pipette to the tip of the syringe, depress the plunger of the syringe to fill (prime) the catheter or pipette with the solution.

Okay, now you are ready to flush the pouch. Proceed as follows:

Gently place the horse in the bowl filled with his own tank water. Very gently and slowly introduce the tip of the catheter through the pouch opening, into the pouch. When you enter the pouch you may meet some resistance. If you encounter resistance when inserting the catheter, I have found that it helps to try different angles, rather than pushing forcefully. I have never dissected a seahorse, but from all the evacuations and flushes I have done it feels to me as if the opening to the pouch is more than a simple opening. It feels like a short tunnel, with folds or pockets of tissue along the walls of the tunnel. I have had to flush/evacuate several different horses. They all seem to be built a bit differently.

I have had success entering the pouch opening straight and then angling the catheter down a bit as well as entering at an angle from the start.

Once you have the catheter tip inside the pouch, depress the plunger of the syringe, flushing the pouch until you see some of the solution coming back out of the pouch. Continue to flush the pouch with about .2 to .3 cc.

Once the pouch has been flushed, you want to leave a small amount of flush inside the pouch. Pulling back on the plunger aspirate the some of the fluid until some of the solution has been removed from the pouch, leaving enough so that the pouch remains softly full, but is not at all taught or tight. Place your horse back in his tank

The next day, prior to the new flush, aspirate the previous days flush from the pouch. Using the syringe with the catheter/pipette attached to the tip, insert it as described above. Pull back on the plunger of the syringe withdrawing the flush from the day before.

Now you are ready to administer the newly mixed flush by repeating the steps described above.

Antibiotic Pouch Washes

If you can obtain a suitable small glass eyedropper with a rubber squeeze bulb, the tip of which you can insert into the pouch orifice, you can use the eyedropper to flush the pouch instead. Otherwise, you’ll have to obtain a small pipette or use a small syringe and catheter for the flushes, as previously described in Leslie Leddo’s pouch flushing tips. You will be flushing the male’s pouch once a day for three consecutive days, using a medicated pouch flush solution.

The first thing you’ll need to do is prepare the pouch flush solution. I recommend using a combination of nifurpirinol and neomycin sulfate for the pouch flushes, since that combo works together synergistically to forms a wide spectrum antibiotic with potent antifungal as well as antibacterial properties (Basleer, 2000). Nifurpirinol and neomycin sulfate are the active ingredients in two different commercial products designed for aquarium use, and both of them should both be readily available at your local fish store. Prepare a 50:50 solution by taking approximately 1/10 teaspoon of nifurpirinol and 1/10 teaspoon of neomycin powder (from a capsule) and mixing them together with about 40 cc (or 2-1/2 tablespoons) of tank water from your seahorse setup. (Nifurpirinol comes in tablet form, so you’ll have to crush a tablet into as fine a powder as possible, using a blender if necessary, and then use 1/10 teaspoon of this nifurpirinol powder for the mixture.) Mix the nifurpirinol powder and neomycin sulfate powder with the tank water very well until the medication is thoroughly dissolved. Avoid any undissolved residue that remains. (You will have to make up a new batch of this solution each day for 3 days.)

If you can’t find both nifurpirinol and neomycin, then you can use either one alone, or substitute kanamycin capsules alone, to make your medicated pouch solution. In that case, just use 1/10 teaspoon of the antibiotic powder and mix it thoroughly with about 20 cc (or 1-1/2 tablespoons) of tank water. Again, make a new batch of pouch-flush solution each day.

And here are instructions from Keith Gentry explaining how to do a pouch-flush directly with Diamox:

Pouch Flush

In cases of recurring pouch emphysema, diamox can be administered as a solution injected into the pouch via an narrow gauge irrigating cannula or plastic 26 or 28 gauge IV catheter sleeve attached to a 0.5 or 1ml syringe (larger syringes should not be used).

Using a blender, mix ½ of a 250mg Diamox tablet with a cup of seawater at the same specific gravity as the tank. Fill the syringe with about .5ml of this solution, avoiding the residue at the bottom of the cup. The seahorse should be held as per the procedure for pouch evacuations.

Insert the catheter sleeve slowly and gently a small way into the pouch opening and inject this solution SLOWLY into the seahorse’s pouch, leaving the solution in the pouch. Make sure you are familiar with the location of the pouch opening.

Never use a metal needle for this procedure.

The procedure may have to be repeated twice to be effective. In stubborn cases, it is recommended to concurrently administer broad spectrum antibiotics. Diamox and antibiotics have been used simultaneously and successfully without appararent side effects.

I believe the dosage of antibiotic is one 250mg tablet of neosulfex per 10 gallons. It’s important you treat the horse in a quarantine tank. Diamox and neosulfex can kill your
biofilter.

For neomycin and sulfa you can use up to 4 times the marine dosage listed on the instruction or are up to 8 times the recommended freshwater dosage. [End quote]

Finally, here are Neil Garrick-Maidment’s instructions for performing his extremely successful pouch flushing procedure:

[open quote]
Hi Pete,

Hope you don’t mind me interjecting on the point about gas bubble in the
pouch but it is important to emphasise a few things.

When I devised and developed this treatment quite a number of years ago, I
was shocked to hear some of the ways people were clearing the bubbles within
the pouch, from cocktail sticks to straws, which caused irreparable damage
to the pouch and the Seahorse. It is vital that great care is taken when
doing this process and the purchase of a fine blunt ended pipette from the
chemist is the best way.

When handling the Seahorse make sure you have a
firm grip with the pouch facing outwards under the water, its best to have
the tail curled around the little finger to add stability. Then insert the
pipette almost vertically, through the pouch opening so the pipette goes
down into the pouch (almost parallel with the body) and not in towards the
body which will cause major internal and secondary problems.

Once the pipette is safely in the pouch then a fine nozzled hand spray (it must be
fine to fit into the end of the pipette) must be used to flush down through
the pipette, you will notice bubbles of gas being vented from the pouch as
you flush the pouch, initially with water from the tank, this stops shock to
the animal and at the same time clears the pouch. This same method (do not
remove the pipette in between stages) should then be used to add medication
etc.

When withdrawing the pipette use a slight twisting motion and remove in
exactly the same direction as it has gone in. The Seahorse will seem a
little shell shocked after this but the immediate release from floating etc
will provide instant relief.

I have had 100% success with this process but
you must be in mind of the Seahorse and its discomfort at all times.
Just before starting make sure you have all your equipment and medication in
place, there is nothing worse than getting part way through and realising
you have forgotten something.

Hope this helps

Best wishes
Neil
Neil Garrick-Maidment [close quote]

One of these techniques will hopefully work well for you, Lynn, depending on what medications and equipment you have on hand or have access to for performing the pouch flushes. But no matter what method you use, the first step is to try manually releasing the trapped gas from your male’s pouch. I find the easiest way to do that is to carefully insert a small catheter or cannula or tiny pipette into the aperture of the pouch, as previously described, and then apply firm but gentle pressure to the outside of the pouch. This usually causes the air to escape through the catheter or pipette. This method works very well but it’s easier if you have three hands or a helper to assist you.

Best of luck deflating your stallion’s bloated pouch and resolving this problem with positive buoyancy, Lynn!

Respectfully,
Pete Giwojna