David Guerra

David Guerra
Midwestern State University | MWSU · Department of Biology




Questions (3)
I'm interested in how different concentrations of vitamins might affect the fish. I have many different brands of food that I would like to test. Vitamins are usually shown as either IU/kg or IU/g but the values between diets that are supposed to be similar are very different. For example, my understanding is that if one of my diets says 1000 IU/kg that means that 1kg of feed will have 1000 IU of vitamin A. Another one of my diets says 30 IU/g so that means that in 1000g (1kg) I would find 3000 IU.
Am I correct? I ask because I would like to be able to convert these values to the same units to be able to compare them. Thank you.
I am using commercially available vitamin A mix for a project. It comes in capsules and is very dense so I thought to dilute it with soybean oil.
The vitamin A solution has an approximate density of 0.8523 g/mL (I calculated this by filling 0.3 ml of the VA solution in a microtube and then weight it [minus the tube weight of course] and it was 255.7mg). Then I added 0.3ml of soybean to the microtube and mixed them. This allows me to easily use a micropipette but now I don't know how much vitamin A solution I'm taking each time (in 20ul of the solution for example).
I need this because I add the carotenoids to a feed and I need to know how many mg I'm adding.
This might have a very simple solution but the fact that is the oil is throwing me off. Thank you in advance.
I'm doing reach in the effects different levels of oxygen have in lizard egg development. The basic idea is to compare the vascularization of eggs caused by normoxia, hypoxia 17 and 15 during angiogenesis. We expect to find a higher vascularization in the eggs under hypoxia as to "compensate" for the lack of oxygen. However, I'm very confused about the methodology I should use. How do I quantify vascularization? What units? What software do I use to assign numeric values to my results for later statistical analysis?
Thank you