Hello all, I am new both to the forum and to raising chickens. I apologize in advance if this question has been asked before. I have four hens that I purchased from a reputable dealer. These hens have been vaccinated for Mareks. Additionally, I recently purchased three 5-day-old chicks from a different vendor. These chicks were NOT vaccinated. I took it upon myself to vaccinate the chicks, as they will be eventually introduced to the hens this spring. I purchased the vaccine and followed all the proper handling directions. I watched a few Youtube videos to see exactly how to handle the chicks during the procedure. Needless to say, it was a nightmare. All the chicks survived, but I cannot say for sure that all of them were successfully vaccinated. My question is this: since I am not sure if the chicks were correctly vaccinated at 4 days old, can I re-vaccinate them again when they are a month old? I imagine that the vaccinated process would be considerable easier, especially since their little bodies are much more substantial and it should be easier to get a proper subcutaneous injection at that time. To be clear, I am NOT asking whether of not the chicks should be vaccinated at all, since all you need to do is a quick Google search to realize that there are as many opinions on this topic as there are users on the internet. I also am not looking to get into a discussion as to what the appropriate age is to vaccinate chicks, as again, there are 1.1 million different opinions on this subject as well. Thanks, Lenny B.