The Preg Calculator app allows the user to input reproductive parameters from their herd and then calculate the required number of pregnancies per interval to maintain the herd. Parameters may be derived from DHI reports or DairyComp305™ with tge appropriate commands provided. Parameters include herd check interval, herd size, calving interval, pregnancy loss rate and culling rate. Data may be saved on the iPad version for future comparison.
To begin, the iPad user should enter the herd name in the text field labeled Herd Name. The date is automatically entered in the Date text field but may be changed by touching in the Date text field and using the date selector. Press Done after selection. The preceding steps are not applicable for the iPhone. Next, all users should choose the pregnancy check interval used on the dairy by touching the Choose Interval selector in the appropriate area: 1 week, 2 weeks or 1 month.
To obtain the data for the Herd Size, Calving Interval, Pregnancy Loss and Cull Rate text fields you may refer to DHI reports or the following table for the DairyComp305™ commands and explanations. There may be differences in values reported by DHI services with respect to numbers generated by DairyComp305™. In cases of extreme variation, please consult your DHI field agent or DairyComp305™ support.
|Click OK to accept default earliest date, Click OK to accept default latest date (results in 1 year period), Click OK to accept default Select Events, Click report tab, scroll to the bottom of the report and note Summary value in column D (Lact>0)
|Sum cint for lact>1
|cint = item storing calving interval (difference in days between current fresh date and previous fresh date)
|Determine the voluntary waiting period using the Egraph command.
In DC305, pregnancy loss may only be approximated due to current programming (10/1/14).
|Enter the voluntary waiting period when prompted by the bredsum\ev command. Pregnancy loss is estimated by dividing the number of abortions by the number of pregnancies obtained. If an abort/pregnancy loss occurs to a pregnancy confirmed less than 35 days, and that pregnancy is not reconfirmed later, the abort is counted in the bredsum table, but not the pregnancy. In this case the user should add the number of pregnancies plus the number of abortions and use that summation as the denominator. The actual abortion rate for the herd should be within the range of these two estimations. Report number in decimal form (e.g., 10% = .10)
|Select 1 year date range. Add the total number sold and the total number died, then divide by the herd size above. Report the number in decimal form (e.g., 36% = .36)
After the parameters have been entered, touch the Calculate button. Values will be entered into the Number of Pregnancies Required, Lact=0 pregnancies and Lact>0 pregnancies text fields. The user may enter the number of pregnancies discovered in the appropriate Pregnancy Check Results fields. For iPad users the deviation from the required is calculated automatically. To save the assessment for future reference, touch the Save button(iPad only). To clear the assessment, touch the Clear button.