I do believe your first thought — that your male has developed pouch bloat or pouch emphysema, a form of gas bubble syndrome — is almost certainly correct. It’s unfortunate that this problem cropped up while you were away tending to a family emergency, but this is not the sort of problem that should result in the loss of your stallion and it is something that can easily be corrected or you must leave town again this Saturday.
It is indeed possible for a stallion to be pregnant and to be having buoyancy problems as a result of gas building up within its pouch at the same time. That’s not unusual and a needle aspiration is definitely the best way to remove the gas or air from a male’s pouch when a possible pregnancy complicates matters. However, if you suspect that a male with pouch gas is pregnant, it’s best to use the needle aspiration to remove the gas from the marsupium without performing a pouch flush with the antibiotic solution.
Pregnant males are particularly vulnerable to chronic pouch emphysema and other forms of gas bubble syndrome (GBS), and it is not uncommon for a male that is carrying a brood of young to develop problems with pouch gas and positive buoyancy. When this reaches the point where the affected male is floating at the surface or having difficulty swimming normally and struggling against positive buoyancy, you have no choice but to release the trapped gas one way or another as soon as possible. Otherwise, the seahorse will be unable to feed and will exhaust itself struggling against the tendency to float, resulting in the build up of lactic acid in its blood and associated changes in blood chemistry (acidosis) that further aggravate its condition.
Pregnancy is naturally a high-risk period for pouch emphysema and pouch gas for a couple of reasons. First of all, breeding males are often especially susceptible to chronic pouch emphysema and GBS in general because of the placenta-like changes that occur in the lining of the pouch during pregnancy. Spongelike, its tissues expand as the capillaries and blood vessels swell and multiply. A film of tissue then forms around each embedded egg, providing it with a separate compartment (alveolus) of its own. The thickening of the wall of the marsupium and elaboration of pouch structures around the implanted eggs result in a dramatic increase in vascularization, and this increased blood supply (hence increased concentration of carbonic anhydrase) transports more dissolved gases to the pouch, increasing the risk of GBS accordingly. The increased blood supply to the marsupium during pregnancy thus makes breeding males increasingly susceptible to the formation of intravascular gas emboli (micronuclei or seed bubbles) at this time, which can result in pouch emphysema and positive buoyancy problems.
Secondly, pouch bloat can be caused by gas produced by the decay of embryonic material and the remains of placental tissue or other organic matter (possibly even stillborn young) within the brood pouch, if the male is unable to flush it out and cleanse it properly by pumping water in and out during its pouch displays (Cozzi-Schmarr, per. com.).
I know of a couple of cases in which male seahorses developed pouch emphysema and/or other forms of GBS every time they became pregnant. When they weren’t breeding, they were just fine, but when they were carrying a brood of young, they were invariably plagued with pouch gas and buoyancy problems. Providing the GBS was managed properly (typically by administering Diamox orally via gut-loaded shrimp, in cases like this), the affected male may be able to give birth normally and recover fully afterwards.
So it’s possible that this could become a recurring problem for your male whenever he becomes pregnant or prepares his pouch to receive a brood of young. If that proves to be the case, I will be happy to help you deal with the situation as it rises. When a gravid male develops problems with pouch gas and positive buoyancy during the course of his pregnancy, I usually recommend performing a needle aspiration to release the trapped gas in a noninvasive manner that make allow the male to carry his brood full term and deliver them normally in due course, as described below:
A needle aspiration is a very straightforward technique that simply involves inserting a hypodermic needle through the side of the pouch, tapping into the pocket(s) of trapped gas or fluid, withdrawing the plunger on the syringe and removing the fluid or gas. If you have never done a needle aspiration before, I know it sounds a bit gruesome, but it is a surprisingly painless procedure for the seahorse and is often easier and less stressful for both the aquarist and the patient than performing pouch flushes or repeatedly massaging the pouch. Not only is a needle aspiration less traumatic, as a rule, but it is also often more effective in removing the trapped gas and relieving the problem. A needle aspiration is easier to perform if you have a helper, since an extra pair of hands is very helpful when you’re ready to withdraw the plunger on the syringe and extract the gas from the encapsulated bubble.
The procedure is accomplished while the seahorse is held under water, just as you would if burping or flushing the pouch, and you grasp the seahorse in the same manner as well.
Prepare the needle and syringe ahead of time by sterilizing the hypodermic. When you are ready, 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.
While the seahorse is thus restrained, use your dominant hand to insert the needle into the side of the pouch (not the front) so you can tap into the pocket(s) of trapped gas.
Remember, you are not performing a subcutaneous or intramuscular injection, so there is no need to use a shallow angle when penetrating the wall of the pouch. Depress the plunger all the way and then insert the hypodermic laterally, from the side of the pouch rather than the front, at a perpendicular angle to the wall of the pouch. Use a big firm, gentle pressure to penetrate the wall of the pouch.
If you missed the pocket of trapped gas on your first attempt, the hypodermic may also withdraw placental fluid from the marsupium and/or yolk from ova implanted within the lining of the pouch, depending on how far advanced the pregnancy is, but that’s not a problem. Very few, if any, of the fetal fry or embryonic young are affected during a needle aspiration, compared to the alternative which is performing a pouch flush and thoroughly cleaning out his pouch.
Don’t worry that performing a needle aspiration will injure your male or cause any irreparable damage to the stallion or the young he may be carrying. I can assure you that needle aspirations will not ruin your male for breeding or cause him any permanent harm. For instance, releasing the air or gas from a tiny dwarf seahorse male is much more difficult than it is for the larger seahorses, and sometimes requires extraordinary measures to accomplish. Here is an account of one such case in which Kirk Strawn — the leading expert on Hippocampus zosterae in the wild — had to evacuate the air from a pregnant dwarf seahorse several times during the course of its pregnancy:
Herald and Rakowicz (1951) found bubbles to occur in the large seahorses, Hippocampus hudsonius punctatus, as the result of gas given off by decaying young remaining in the pouch after delivery. They recommended removing the bubble by inserting a needle into the opening of the pouch after delivery. This is a more difficult operation on the little dwarfs. It is more easily accomplished either during courtship or following the delivery of young — at which times the opening to the pouch is dilated. Inserting a needle through the entrance of the pouch does not ruin a male for future breeding. A male kept away from females from February until June had bubbles removed on three occasions by puncturing the side of the pouch with a needle and squeezing out the bubble. (Males go through the motions of courtship and may pick up bubbles even if no females are present.) On June seventh he was placed with a ripe, freshly caught female. On the seventeenth I cut a slit in the side of the pouch and removed a bubble and two partly formed babies. By the twentieth [3 days later] the slit was healed over, and he had another air bubble. On the 23rd I partially removed this bubble by forcing a needle through the entrance of the pouch. On the 25th [2 days later] yolk came out when the needle was inserted. On July 5th he gave birth to a large brood after which a bubble was squeezed out of the dilated opening of the pouch without the aid of a needle. The next day he sucked in another bubble while courting. Although removing bubbles does not permanently damage the fish, it is much easier to put a fence, such as a cylinder of plastic screen, around the air stone and its rising stream of bubbles.
Note that in this episode, Strawn had to perform needle aspirations on his pregnant male multiple times in addition to eventually performing surgery and cutting open the side of the pouch on one occasion. Yet even after all of these traumatic events, some of which resulted in yolk or embryonic young being released along with the air, the male still went on to deliver a large brood normally at the appointed time afterwards. So you needn’t be concerned that your efforts to evacuate the gas from your stallion’s pouch will cause him injury or damage, or necessarily doom any fertile eggs are developing young he may still be carrying.
You must release the gas that is bloating his pouch and causing positive buoyancy to provide a stallion with pouch bloat with some relief, and I would suggest performing a needle aspiration this time and/or treating your male with Diamox (the tablet form of acetazolamide) as soon as possible. Of these two treatment options, a needle aspiration is probably your best bet because it will provide your stallion with immediate relief from the positive buoyancy (Diamox may take several days to work and it is a prescription drug that is often difficult for hobbyists to obtain). As I said, removing any gas that is build up via a needle aspiration will have a negative impact on very few of the developing young as compared to attempting to manually evacuate the gas by burping the pouch or performing a pouch massage or pouch flush.
In short, it is the changes the marsupium undergoes during pregnancy that leave the gravid male so susceptible to pouch emphysema, and a needle aspiration is the best way to remove the gas that is built up within the pouch in such cases. But it’s best to avoid flushing the pouch with the antibiotic solution when you perform the needle aspiration(s) if you suspect that the male may be pregnant and carrying embryonic young or fetal fry.
The other alternative is to treat your stallion with Diamox (the tablet form of acetazolamide). If the seahorse is still eating, it’s best to administer the Diamox orally by feeding the seahorse shrimp that have been injected with a solution of the medication. You get the Diamox into the food by preparing a Diamox solution, as described below, and then injecting it into live feeder shrimp or even the large Piscine Energetics frozen Mysis relicta. The Diamox is deactivated fairly quickly once you prepare the solution for injecting, so you must prepare a new Diamox solution each day during the treatment period. Here’s how to proceed if you can obtain the medication and prefer to treat your stallion with the Diamox rather than a needle aspiration:
Administering Acetazolamide/Diamox Orally
I have found that the Diamox 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 Diamox 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."
Volcano shrimp or red feeder shrimp from Ocean Rider (iron horse feed) 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 has cured seahorses with tail bubbles and pouch gas using this technique. She found 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. So if your Vet or family doctor will prescribe the Diamox for treating your seahorse, ask them also to provide a 1/2 cc insulin syringe with a 26-gauge needle.
If you are using 250-mg tablets, Leslie found that 1/8 of a tablet provides enough Diamox for several days’ worth of injections. In other words, 1/8 of a 250-mg Diamox tablet provides enough of the medication to inject two shrimp daily for about 5 days. So each day, I would take 1/8 of a tablet and shave off approximately 20%-25% of it to make the Diamox solution for that day’s injections. (NOTE: if you are using 125-mg Diamox tablets, adjust your dosage accordingly — that is, start with 1/4 of a tablet and then shave off 20%-25% of it to make the Diamox solution.) Then crush the Diamox you have shaved off and to a very fine powder and dissolve it in a very small quantity of water.
Use the resulting solution to inject two of the live feeder shrimp or frozen Mysis relicta and feed them to the affected seahorse immediately after injecting them. Don’t allow any healthy seahorses to eat the medicated shrimp instead of the ailing pony, since it could be bad for them. To prevent this, you may have to target feed or isolate the sick seahorse when feeding it the gut-loaded shrimp. Isolating the patient briefly in a Critter Keeper or something similar when feeding him the medicated shrimp often works well.
Diamox doesn’t dissolve especially well in water; there’s always a residue of undissolved material left behind. Try to avoid this residue when you draw up the medicated solution in your syringe, the particles can sometimes clog up the fine bore needle when you are trying to inject the shrimp.
Each day you will have to prepare fresh Diamox solution to inject the shrimp for that day’s treatment, so just repeat the steps above each day. He should show improvement rapidly, with 2-3 days. If not, after you have fed him injected shrimp for 3 straight days, give him a break from the Diamox for a few days and try again. (Diamox can suppress the appepitite, so feed him unmedicated/uninjected shrimp for a few days to keep him eating and help restore his appetite.) Then feed him Diamox-injected shrimp again at the rate of 2 per day for a total of 3 more days, but this time increase the dosage of Diamox slightly (shave off a bit more of the tablet each day when you mix the new Diamox solution).
Best of luck resolving this problem, seasons. I believe a needle aspiration will be the easiest and least stressful way to release the trapped gas from your stallion’s pouch, but if he is not actually pregnant, which is a distinct possibility, any of the other methods for evacuating the pouch gas described in the discussion on this forum titled "Upside Down Seahorse" may also be effective.