However, make sure you collect a fetus and not a cotyledon.Cotyledons are part of the placenta, have a capsule-like appearance and may look somewhat similar to very young fetuses.The Julian date of 496 occurs on May 11, the date the fawn would have been born.Once you determine conception dates, it’s time to graph the data.However, a quick inspection will easily distinguish between the two.Once the fetus is in hand, you can age it and determine conception and birth dates in less than five minutes at camp or on your tailgate using a fetus scale. Select the calendar that allows you to subtract the days from conception from the Julian date and also allows adding the days to parturition to the Julian date.A simple bar chart works well, and you plot the number of pregnant does in your harvest data (the sample size) on the vertical axis.
Thus most harvested deer, even if pregnant, have fetuses far younger than 35 to 40 days.
This isn’t a problem in areas with late deer seasons and/or early ruts.
However, many northern firearms seasons coincide with or immediately follow peak breeding.
Once you know the number of days from conception, flip over to the other side of the fetal scale to determine the date of conception. Locate within a calendar the date the doe was harvested and convert that date to a Julian date (which runs from one to 365 days on one calendar and from 366-730 days on the calendar for the subsequent year). On the calendar on the fetal scale, locate the date block with the Julian date found in No. Julian dates allow you to calculate the number of days between two calendar dates by simple subtraction.
The fetal scale has a calendar that makes this conversion simple. Subtract the age of the fetus in days (days from conception as measured on the scale) from the Julian date noted in No. The Julian date of December 15 is 349 (it’s the 349th day of the year).