Egg tail bud formation problem in T. marmoratus

[garrison]

I recently had a pair of T. marmoratus lay some eggs and I am aware that there is supposed to be a 50% mortality rate in them due to the tail bud formation problem.

My question is what point in egg development is this noticeable? I have taken less than 10% out with fungus, but I would imagine this would be quite normal in any batch of eggs, and most of the others seem to be forming some shape out of their cell mass.

 

[jennifer]

It's a bit complicated. Do you remember high school biology and Punnet squares for Mendelian genetics? If you do, then these percentages will make sense:

These animals have two forms of their first chromosome, a short form and a long form. The 50% of the offspring that inherit long/short are the normal ones. The 25% that inherit long/long begin to develop into a nice kidney-bean shape, then they arrest and die. The 25% that inherit short/short may start to develop, but they stay round looking. The embryos that have arrested development (either type) may take a bit longer to get moldy than an infertile egg would.

This gives more details, or may just be more confusing:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=3209981&query_hl=1&itool=pubmed_docsum

 

[garrison]

Thanks Jenn,
Actually that paper cleared it up a bit, I guess being a biology graduate does help for something

 

[jennifer]

By the way, I checked at work and I was able to get a PDF of the full article. If anyone is interested, send me a message through my forum profile.