sow and litter

Fine-Tuned Breeding Can Boost Farrowing Results

This fifth and final article in this series focuses on the impact that artificial insemination (AI) technicians can have on farrowing rate and total pigs born when day of the week and hour of the day that insemination took place are known. Previous articles in this series are available at

Again, this series features the combined performance on 11 U.S. and Canadian farms and includes 80,013 matings in 2011.  To be included, a breeding technician had to average over 10 matings/week.

The 34 qualifying technicians had an average farrowing rate of 86% and a total-born average of 13.46 pigs/female farrowed for 52 weeks. To effectively analyze the data, we needed female identification (ID), breeding technician ID, a semen batch code or boar ID, and the time of the day the mating took place, recorded in military time (01-24).

We used the following AI technician analysis reports:

·        Breeding Technician Analysis Farrowing Rate Charts

·        Breeding Technician Analysis Farrowing Rate Report

·        Breeding Technician Analysis Total Born Charts

·        Breeding Technician Analysis Total Born Report

·        In-Depth Analysis

·        Breeding Weekly Analysis

Farrowing Rate and Total Born

Chart 1, Farrowing Rate by Day of the Week Bred, represents 80,013 matings with a farrowing rate of 86%.  Since most of the farms in this dataset wean twice a week, females mated/day runs from 6.2% mated on Thursday (farrowing rate, 81.8%) to 21.8% mated on Monday (farrowing rate, 86.8%).

It is easy to forget that 30% or more of the first matings commonly occur on weekends. Some sows are mated a second or third time on Saturday or Sunday. Therefore, it is important to monitor who is responsible for breeding on the weekends. And it is important that adequate labor is available to help ensure the crew is doing high-quality matings. There is always the temptation to rush through the matings to get out of the barn earlier. We encourage our clients to check the farrowing rate of each technician to make sure they are doing a good job when it is their turn to work on weekends.

Table 1 compares breeding results of two technicians.  Tech N was the first and second inseminator of 250 sows on Sunday (farrowing rate, 78.8%) and 680 females on Saturday (farrowing rate, 83.1%). When we look at the rest of the breeding week, Tech N’s farrowing rate for females bred on Monday through Friday was 86.1, 85.2, 85.8, 80.0 and 86.5%, respectively.  So, what is going on with weekend breeding?

When we look at results by Tech AB for females bred the first and second time, the farrowing rate for those bred on Sunday was 86.1% (531 matings) and on Saturday was 90% (300 matings). For the rest of the week, starting on Monday, farrowing rates are 85.3, 91.5, 89.1, 74.5 and 90.4%, respectively.  Clearly, this farm needs to look at why breedings on Thursday drop to 74.5% farrowing rate.  On some farms, females bred the first time on Thursday are returns to estrus, females weaned late and problem breeders.  

Chart 2 and Table 2 features Total Born by Day of the Week Bred and by Technician.  In this dataset, the average total pigs born is 13.46 pigs/litter with very little variation by day of the week. However, when we study these farms individually, we see more variation by day of week bred.

Again, Table 2 features data from two technicians.  Tech N mated 427 females twice on a Monday with total born average of 13.54 pigs/litter, while 309 females were bred on Saturday and averaged 12.98 pigs/litter – a difference of 0.56 pigs/litter. Was this difference due to less labor or rushing through inseminations on Saturdays? Likewise, Tech W’s performance on females that were mated twice, the lowest total born was from females mated twice on Saturday (12.38 pigs/litter) compared to his best day – Wednesday – when total born averaged 13.44 pigs/litter. 

Time of Day Bred Matters

Most recordkeeping programs allow hour of the day the mating occurs to be recorded.  We encourage our clients to record this information. Chart 3 and Table 3 reflect Farrowing Rate by Hour of Day.

Farrowing rate clearly goes up and down, depending on the time of day females are bred.  Some of this variation is likely due to differences in the females being inseminated. Breeding recently weaned sows during the first few hours of the day will usually show higher farrowing rates. If recycling females or later weaned sows are bred during the first few hours, lower farrowing rates are often seen.

Likewise, it is not unusual to see a drop in farrowing rate in females bred in late morning.  This may correlate to worker’s break time or lunch time when they are more likely to rush through the insemination process. Slippage can also reflect a fatigue factor when many sows are bred without a break.

In Table 3, Tech AB has a farrowing rate average of 87.6%. Looking closer, when females are bred the first time at 11 a.m., farrowing rate is 82% vs. 88.7% when bred at 10 a.m. or 89.8% when bred at noon.

Chart 4 and Table 4, Total Born by Hour of Day, shows some hour-to-hour variation.  This is primarily trend data, so it is important that there are enough observations to validate the trend lines.  In this example, total born/litter ranges from 12.00 to 14.19 pigs.  Table 4 shows Tech AB had a variation from 13.10 to 14.28 pigs/litter and a minimum of 10 farrrowed. 

Case Study

One of our clients had seen a drop in farrowing rate, so we ran an AI technician report and narrowed the problem to sows being bred late in the afternoon on weekends.  In this case, the technician was not allowing females to calm down after workers entered the barn, turned on the lights and equipment. By waiting at least an hour before insemination, farrowing rates improved by 2-3 sows/week.  If they had not been recording the hour of the day that inseminations took place, we would never have been able to identify this problem.

Other factors that can affect farrowing rate includes semen source and handling, sow/gilt fertility factors, heat detection methods and proficiency of the AI technician.

At SMS, we continually look for new ways to analyze data and present it in new ways to make it easier for the farm employees to identify and understand a problem. We then try to give them new ideas on how to manage the any production shortfalls.  To begin participating in the SMS Benchmarking program and see how your farm compares, please contact us by e-mail at mark.rix@swinems.comor

Come See Us at Expo

We are exhibiting at World Pork Expo, June 6-8 at the Iowa State Fairgrounds, Des Moines. Stop by tent # 4837 to meet and visit with Ron and Mark.

Key Performance Indicators

Tables 5 and 6 (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

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