Re:over-due dad?

Dear Lisa:

Hold fast! As long as your gravid male is not experiencing problems with positive buoyancy, which might indicate that his pouch is swollen with excess gas rather than developing young, chances are that all is well and you just need to be patient a little while longer.

It’s not unusual for expecting males to go off their feed a bit as their pregnancy progresses, and my best guess is that your stallion is just about ready to pop. Keep an eye on his breathing rate. When the onset of labor and birth is imminent, the male will begin to shows signs of distress and his respiration rate will increase to 70-80 beats per minute at normal aquarium temperatures (~75°F). Parturition is released by the hormone isotocin and there’s not much you can do to induce labor in a male that is overdue.

As you know, Lisa, the fully developed young emerge from their individual compartments and shake loose into the lumen of the pouch prior to birth (Vincent, 1990). They become very active toward the end of the pregnancy and can sometimes be seen wriggling about through the membrane of the swollen brood pouch at this time. This appears to be every bit as uncomfortable as it sounds, since expecting males become agitated and distressed as the big moment approaches. They experience definite labor pains when birth is imminent, evident as a series of powerful contractions, and soon begin pumping in time with these birth spasms in order to forcibly eject the fry from their pouches. Labor usually begins well after dark in the early morning hours (Vincent, 1990). The distraught male may pump and thrust vigorously for hours before finally ejecting the first of the newborns (Vincent, 1990). The fry are expelled singly or in ones and twos at first, but are soon spewing forth in bunches and bursts of a half dozen or more.

Delivering a large brood this way is hard work, and the exhausted male will pause periodically to recover from his exertions, gathering his strength until he is caught in the throes of another round of contractions. In some cases, it takes 2-3 days for the entire brood to be delivered in this manner.

In short, I wouldn’t be overly concerned about the situation at this point, Lisa. As I discussed with Donna earlier in this thread, there are many factors that can influence the gestation of a pregnant male, and I have seen several instances where a gravid Hippocampus erectus experienced an unusually prolonged pregnancy and ultimately delivered a healthy brood of babies after many more than 30 days had elapsed.

Having said that, males do occasionally have complications during their pregnancy that can cause serious problems. Some of the embryonic young or fetal fry may expire at some stage of their development. When this happens early in the pregnancy, the failed embryos are simply resorbed, and when it happens late in the pregnancy, they are normally delivered as stillborn young along with the healthy newborns. But in rare instances, the decomposition of the unsuccessful embryonic young and fetal fry can result in the build up of gas within the marsupium. This is usually evident because the male will have buoyancy problems as a result and begin to struggle increasingly against a tendency to float. As long as your male can swim normally when he wants to, and can remain at the bottom of the tank as usual, then you can be confident that his brood pouch is swollen with developing young rather than the gases of decomposition. And, in that case, Lisa, I expect it will be just a matter of time before the newborns are eventually forthcoming.

In the meantime, just hold fast, continue to encourage him to eat, maintain optimal water quality and good aeration/oxygenation, don’t separate him from his mate, and provide him with a stress-free environment in which to complete his pregnancy.

Best of luck with your overdue dad and his subsequent brood of babies, Lisa!

Respectfully,
Pete Giwojna