Seasonal impacts on performance
Investigating seasonal impacts on performance begins by focusing on total number born and weaned by farrowing crate, by weaning age and by female farrowed.

Sow Farm Performance Measures Affected by Season

As we continue to look at the seasonal effects on performance of a select set of farms in the Swine Management Services database, this week we will focus on total number born and weaned by farrowing crate, by weaning age and by female farrowed.

As we continue to look at the seasonal effects on performance of a select set of farms in the Swine Management Services database, this week we will focus on total number born and weaned by farrowing crate, by weaning age and by female farrowed.

We are still using the 66 farms representing 178,454 females – 46 are U.S. farms (125,845 females with an average mated female inventory of 2,736 females per farm) and 20 Canadian farms (52,620 females with an average of 2,631 mated females/farm). The weekly data was collected for the last 104 weeks ending June 30, 2012. Because the data was collected by week, we can see the effect of season on a two-year time period.

To look at how efficiently the farms are running, we created charts based on number of farrowing crates. In Chart 1, total born/crate/year, you will notice that the total born average per crate is 192 pigs, but the variation is large – 173 to 203.2 pigs/crate.

Our Canadian friends are doing a better job with an average of 212.6 pigs/crate (191.9 to 231.1 pigs/crate range) compared to the U.S. farms averaging 184.3 pigs/crate (162.9 to 197 pigs/crate range). As Chart 1 shows, there is some seasonal effect as total born drops in late November due to the lower farrowing rate of the summer breeding, although the dip is much less for the farms in Canada. Over the last 104 weeks, the trend line for pigs born/farrowing crate is improving in both countries.

Chart 2, total born/crate/year, by farm, shows the lower farms at 130 pigs/crate and the top farms at 230 pigs/crate – a 100-pig difference. We are not sure how much those extra pigs help lower facility costs/pig; however, it most assuredly has some effect. Most of the farms had an improvement in total pigs born for the 12 months ending in mid-2012.

In Chart 3, pigs weaned/crate/year, the 66 U.S. farms averaged 153.7, with an average between 143.9 and 162.4 pigs. Again, Canadian farms are weaning more pigs per crate. Canadian farms are less affected by the summer heat that caused some drop in farrowing rate.

Looking back at total born/crate/year (Chart 2), you will notice a drop from an average of 192.0 pigs born/crate/year to weaning 153.7 pigs/crate/year – a loss of 38.3 pigs/crate/year, which includes stillborns, mummies and preweaning death losses. That reflects about a 20% loss of potential pigs.

Chart 4, pigs weaned/farrowing crate/year, by farm, shows several farms are weaning over 180 pigs/crate/year. At the low end are farms weaning 136 pigs/crate/year.

We also took at look at whether season is affecting weaning age. Chart 5, weaning age, shows the 66 farms average 19.5 days of age at weaning, with a range of 19.1 to 19.9 days for weekly averages. Canadian farms wean slightly younger, averaging 18.1 days vs. U.S. farms at 20.7 days.

Chart 6, weaning age, by farm, shows a wider spread in ages – 16.5 to 23.5 days of age. The trend line for weaning age is flat with some seasonal variation in January, which reflects more returns to estrus and non-cycling weaned females bred in September and early October.

Over the last few years, weaning age has increased and is now stabilized at 20+ days. Some farms are more concerned about producing more pigs per year even if it causes a drop in weaning age and weight. With the cost of starter feed, weaning pigs younger than 18 days of age should be evaluated against what the effect of weaning older, bigger pigs would have on total feed cost vs. weaning more pigs per crate.

In Chart 7, total born/female farrowed, there has been an improvement over the last 104 weeks. Looking at the 66 farms in the dataset, total born has risen. The all-farms average in the 104-week snapshot averages 13.51 pigs, with a range of 13.10 to 13.86 pigs. Total born/female improved slightly faster in the Canadian farms the first half of 2012.

Chart 8, total born/female farrowed, by farm, shows a lot of variation in total pigs born for a 12-month period – ranging from 11.0 to 15.7. Most of the farms in the data set showed an increase in total born the last 52 weeks of production.

How does your farm compare on pigs weaned/crate/year? Which do you consider to be more important – the cost/pig produced at the sow farm or saving some high-priced feed by increasing weaning age?

There appears to be some seasonal effects on total born. Most of the drop is caused by summer heat impacting farrowing rates and a drop in weaning age when extra sows are farrowed in late-December and January, due to breeding more returns to estrus and late-cycling females in late summer. Even with the improvements in facilities to reduce the effects of summer heat, it still has some effect on pork production.

Past Columns Posted at

Previous “Production Preview” columns can be found at Click on “newsletters,” then the respective date of the Weekly Preview issue you are interested in.

Key Performance Indicators

Tables 1 and 2 (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.comor

Mark Rix and Ron Ketchem Swine Management Services, LLC

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