It’s KEGO TIME!
“Kego” is a Japanese word for the baby silkworm. One site that I saw translated it as “hairy baby.” This worm, actually a caterpillar, is the first stage of the life cycle of the domestic silk worm, Bombyx mori. When the kegos hatch out of their tiny pinhead-sized eggs, each one is about the size of a typewriter dash. After a month of thrice-daily feedings, they will be about the size of my little finger, full of silk and ready to spin their famous cocoons.
This is the second year that I have raised silk worms. Last year, I bought silkworm eggs, and after one false start, managed to get them up and running, chomping their way through mulberry leaves at a phenomenal rate. Out of a package that was supposed to contain “at least fifty” eggs, I ended up with over a hundred cocoons; I was exceptionally pleased. About twenty were allowed to fully pupate, emerge as adults (or imagos) and lay eggs – this year, I was proud to repeat the experiment using the eggs I saved through the winter from last year’s project.
If you have access to mulberry leaves, and think you might like to try raising some silkworms, let me know – I have lots of extra eggs!
I took the eggs that I wanted to hatch out of the refrigerator Wednesday before last. They began hatching this past Friday. When I came home from work, a single solitary worm had made its way out of the egg, and was resting on a piece of leaf. Chris had found it when he arrived home. They’ve been selected through thousands of years of breeding, and they are totally used to being hand-fed; if they are placed more than a short crawl from food, they will die. I put more leaves in their little brood-box (a Wendy’s salad container) and then there were more in the morning – and even more when I got home from work Saturday. By now, late Sunday night, there are probably 50 or more crawling around, munching on the leaves. There are probably another 100 or 150 eggs left to hatch, and they will hatch out over the next couple of days. Traditional Oriental wisdom says that the silkworms should be fed leaves that are the same age as the worms themselves; as they get older, they need more leaves, and bigger leaves, to produce silk, but as babies they need only the very tenderest tip-most leaf of each branch. These tender leaves dry out quickly, so they have to be replaced three times or so each day – keeping a plastic lid on the container allows you to make do with 2 feedings, by maintaining enough humidity in the container. Gotta be careful to avoid mold, though – it’s fatal to the worms. By the time they’re a couple of weeks old, they’re eating full-sized leaves, and the multiple feedings aren’t about keeping them in moist leaves, they’re about keeping up with the worms – they go through a LOT of leaves in the last week before cocooning. One Japanese site in English says, “Week 3: Now the worms begin eating, deadly eating!” They spread out a little as they get bigger – the tiny salad dish becomes 2 large plastic cake-boxes, so that there’s enough space for worms and leaves.
Once they’re ready for the final molt, they start climbing up… and rearing their heads up and making a weird figure-eight move. It looks like they’re dancing. Then they spin cocoons, and pupate for 2 weeks or so. They only live 2-3 days, sometimes less, as adults – they are flightless, fuzzy, and very cute. Most silkworms never make it to be moths; cocoons that are selected for silk-reeling are heat-treated to kill the pupating larva, and the silk is reeled off. The pupae form a significant source of protein for many of the Asian countries where they’re raised; I tried one, and they’re not all that. Definitely taste like bug.
I’m going to keep track of the silkworms, and hopefully post more journal entries about their progress.