Sluggish boa; need advice!

[Psidewindr]

Hi all, I've become a little concerned over the past few days as my 1.5-year-old hog island boa has become a bit sluggish. He is isually quite active, especially at night, but has pretty much been staying in his hot spot hide the past couple days.
Temps are around 91 F on the hot side and 78 F on the cool side. As it's gotten a little cooler in California lately, I recently added a 100 watt ceramic heater to raise ambient temp a bit. Humidity in the room stays between 43 and 50%. He's never had a problem with shedding.
So, I'm not sure what's going on or if I should be concerned. I cannot see any signs of illness--no respiratory problems, swelling, or skin issues. Eyes are clear so I don't think he's starting a shed or anything.
The only difference I can account for is last Saturday and Sunday I fed him rats (one on each day) that were a little on the small side. Normally I feed him one medium rat but since these were a little small, I fed him two days in a row. The rat on day two was slightly wet and I am concerned he may have swallowed some substrate (aspen bark). But I didn't see any large pieces get swallowed and I used tweezers to remove any pieces he was about to swallow.
A day or two after he fed, I noticed a few urate excretions (one was more runny than usual) and he has not defecated since the feeding.
If anyone has any thoughts or suggestions, I would greatly appreciate them. I'm getting worried. Thank you.

[bigsnakegirl785]

This is often a good sign of an impending shed cycle in my more active snakes. Generally, humidity inside the enclosure will be different than the room's humidity. If you kept your house 70-80% you'd quickly become overrun with mold, but it's possible the humidity may be higher inside the enclosure or they have a humid pocket they can hang out in and that's why you haven't run into problems yet.

Shedding happens in these stages:

1. Beginning of shed: hiding away, pink belly, darkening of colors, scale separation in the head sometimes apparent in this stage but usually not until they go blue. I can usually notice subtle color/iridescence changes a couple days before their belly goes pink, and their bellies go pink a few days to a week before they actually turn blue.

2. "Blue phase": they will turn a milky blue all over, especially apparent around the eyes and belly, and any dark pigmented areas. This generally lasts a few days to a week.

3. They clear up. The blue tint goes away, and they will look much like they normally do, this lasts anywhere from one day to a week before they actually shed. You can miss this stage if they shed on the same day they clear up, and you're not checking on them every day (which I don't advise doing anyways).

Always feed one prey item, even if that prey item is undersized. If you do feed multiples, they must be equal to or less than the weight of their normal prey size and be within the same sitting. Feeding them on separate days means you're giving them the second prey item long after their acidity has reached its peak and fallen. It's still higher than during a fasting period, but not quite high enough to begin digestion of the second prey item properly. He should still digest it fine, but a sensitive individual might not be able to, and could regurgitate up to a week after eating. You do not want to overfeed, so multiples are not recommended, but this one instance should not harm him. I would not make a habit of it, though.

Your boa is also quite large for it's age, if it's already eating medium rats. My boas of that age are either still eating mice or weaned rats. Even my almost 2.5 year olds aren't that big yet. If the mediums don't leave a bulge, I'd feed them every 3-4 weeks. If it does leave a noticeable bulge, I'd either move down a prey size and feed every 2-3 weeks, or feed a medium every 4-5 weeks.

[Psidewindr]

Thank you so much for the reply. I was worried he had ingested substrate or that my feeding mistake had caused a problem (which it may have). But, as you thought might be the case, he went into shed about a week after I wrote the original post. He also had a large bowel movement right after. I was relieved. Well, we both were. Haha

I expected he would be rather hungry after this series of events, but he refused to eat the day after. Regarding prey size and feeding frequency, once he has swallowed the rat, there is no discernible bulge. Are you suggesting feeding every 3-4 weeks because he is big for his age or just as a general rule? Most of what I have read suggests 7-10 days.

Thanks!

[dannybgoode]

Boas should be fed infrequently - 3 or 4 weeks is the rule for a boa of this size. When mine is an adult she'll be going 6 weeks between feeds and sometimes even longer. The large constrictors really don't need that much and in general they are grossly overfed in captivity.

They are completely different to say American rat snakes (Pantherophis sp.) for example that require a good meal every 10 days or so as an adult.

A boa should have a nice square shape, slightly loose skin and muscle clearly visible. Any roundness and they're likely overweight. I've seen some thoroughly obese snakes and they don't look good!

Regarding substrate - assuming your temperature are ok then it's nothing to worry about it they swallow a bit.

[bigsnakegirl785]

Thank you so much for the reply. I was worried he had ingested substrate or that my feeding mistake had caused a problem (which it may have). But, as you thought might be the case, he went into shed about a week after I wrote the original post. He also had a large bowel movement right after. I was relieved. Well, we both were. Haha

I expected he would be rather hungry after this series of events, but he refused to eat the day after. Regarding prey size and feeding frequency, once he has swallowed the rat, there is no discernible bulge. Are you suggesting feeding every 3-4 weeks because he is big for his age or just as a general rule? Most of what I have read suggests 7-10 days.

Thanks!

He is very large for his, likely bigger than either of my 2.5 year olds (they're ~4' eating weaned or small rats every 3 weeks), but it's also because I'd normally feed a boa of that size every 3-4 weeks. My big adults only eat every 4-6 weeks and then have 3 months without food, so they eat max 9 meals a year.

He may just not be full, I'd continue waiting and offer in another few weeks. He'll shed any excess fat (visible or non-visible) with time on a proper diet.