In the last few months, we have fielded numerous calls and reviewed a lot of farm data to take a hard look at why there is so much variation in farrowing rate between farms and weeks of the year.

We know that each 1% change in farrowing rate affects pigs/sow/year by 0.34 pigs.  Remember, farrowing rate has three variables – the female, the semen and the artificial insemination technician.  If each performs at 90%, the farrowing rate is 0.90 x 0.90 x 0.90 = 73%.  To achieve a 94% farrowing rate, all three variables need to be at 98%.

We selected 12 farms from our data base for review. In Chart 1, farrowing rate, by week, shows the wide variation between farms.  Farm 9 had the best average for the 52-week period in the dataset, which ranged from 83.9 to 98.3% to average 90.8%. Farm 3 ranged from 68.8 to 95.1%, but still averaged 89.4%.  Farms with the lowest farrowing rates were Farm 10 at 76.7%, ranging from 57.5 to 87.0% and Farm 7 at 79.3%, with a range of 53.5 to 91.0%. 

Table 1 shows the variation for nine farms within a week.   At random, we selected 20 of the 52 weeks of data. Looking at Week 1, the farms ranged from 56.4 to 94.9%, a 38.5% difference. In Week 8, the range was narrower – 77.7 to 92.1%. Week 11’s range was narrower still at 78.1 to 95.4%. But in the random week’s selected, Week 20 had the least difference, ranging from 81.3 to 92.3% or a 13.8% difference amongst the farms.

Farm 1 had an 88.1% farrowing rate average, but the variation ranged from 62.3 to 98.6%. Clearly, the week-to-week variation has a big effect on how many sows farrow each week and how many pigs are weaned each week. 

Currently, farms are reporting lower than expected farrowing rates for sows bred in January to March. Data also shows some of the farms with lower farrowing rates are also reporting a drop in total pigs born/litter.

This has prompted some calls from semen suppliers asking for extra reports and further analysis to get a handle on what is causing these shortfalls.

Semen Handling Tips

When you see a week where farrowing rate is 10% below the previous week, these are some questions you should ask:  Are more sows recycling? Was your best insemination technician on vacation? Did semen arrive late that week? Were several females only mated once?

If you feel semen could have been an issue, the following suggestions could help improve farrowing rate:

  • Record temperature of semen at delivery to monitor changes during transport.
  • Monitor and record high/low temperatures in the cooler daily using a digital thermometer with the probe placed in a bottle of water.
  • Record semen batch numbers for each insemination so farrowing rate by batch of semen can be tracked.
  • Place semen cooler in an air-conditioned room during the summer to reduce stress on the semen cooler.
  • Place semen bags to be used in a cooler with cool packs and only take what you are going to use for that breeding period.
  • Any extra semen brought back from the breeding barn should be used that day or discarded.
  • Share farrowing rate and total born data with your semen supplier.

Tracking Semen Batch

To show the variation in farrowing rate by semen batch, we created Chart 2. Only semen batches with 10 semen doses were included.

Farm 1 ranged from 81.8 to 100% to average 88.1%. Farm 4 ranged from zero to 100%, but still averaged 88.6%. And, Farm 5 ranged from 62.5 to 93.9%, with an average of 77.3%.  You can see the importance of keeping detailed records, by semen batch, to share with your semen supplier.

Breeding Technicians

Chart 3 shows farrowing rate by breeding technician, tracked by day of the week that the inseminations occurred. Of the 26 breeding technicians, Technician A had the highest farrowing rate at 90.7%, ranging from 92.1% for Saturday matings to 86.1% for Thursday matings.  Technician M’s average farrowing rate was 86%, with lowest farrowing rates from matings that took place on Wednesday (74.2%) and Sunday (79.9%).  Technician Z had farrowing rate average of just 77.7%, but did a very good job on Sundays, which had a farrowing rate of 88.6%. Monitoring technicians by day of the week can offer insights into why some technicians perform better on certain days.

It is important to be able to look at farrowing rate by technician, by parity, by day of the week mated, by wean-to-1st service interval, and for number of matings and services.  In addition to farrowing rate, total pigs born /litter needs to be reviewed. 

As the data shows, there is considerable variation in farrowing rate by farm, day of the week, technician and semen batch. If you want to improve the farrowing rate at your farm, you will need this type of detailed information to identify the reasons farrowing rates slip.  Be sure to provide your semen supplier with this information. Again, a 4% improvement in farrowing rate produces 1.35 more pigs/sow/year.

Key Performance Indicators

Tables 2 and 3 (below) provide 52-week and 13-week rolling averages for key performance indicators (KPI) of breeding herd performance.  These tables reflect the most current quarterly data available and are presented with each column.  The KPI’s can be used as general guidelines to measure the productivity of your herd compared to the top 10% and top 25% of farms, the average performance for all farms and the bottom 25% of farms in the SMS database.

If you have questions or comments about these columns, or if you have a specific performance measurement that you would like to see benchmarked in our database, please address them to:  mark.rix@swinems.com or ron.ketchem@swinems.com.