Should You Be Tracking Gestation to Lactation Feed Ratio? By Todd Thurman from Swine Insights International


Todd Thurman Swine Insights International

Piglets Nursing a Sow

A few months ago, I had an interesting conversation with a client. They had been diligently monitoring overall sow feed intake and sow feed cost per pig for some time. To add a new dimension to their analysis, I proposed that they start tracking the ratio of gestation feed to lactation feed. Tracking this metric is surprisingly uncommon, however, it holds a wealth of insights that can significantly impact farm performance. High levels of gestation feed intake can serve as a warning sign of potential issues in the farm. Let’s explore why monitoring the gestation-to-lactation feed ratio is a valuable tool in optimizing sow farm efficiency.

When gestating sows consume an unusually high amount of feed, it may indicate underlying problems. This could mean that the sows are too fat or that they are experiencing significant weight loss during lactation or both. Both scenarios are cause for concern and warrant closer examination. High gestation feed intake can be indicative of suboptimal sow body condition. Sows that are too fat are at risk of poorer reproductive performance and perhaps most importantly, low lactation feed intake. On the flip side, if sows are losing too much condition or body weight during lactation, it can lead to longer wean to service intervals, lower farrowing rates and smaller litter size in subsequent litters.

Conversely, higher lactation feed intake is strongly correlated with superior sow farm performance. A greater percentage of lactation feed  tends to result in better outcomes. Sow feed intake is the fuel that drives the engine of the sow farm. When sows consume maximum lactation feed, they have the resources necessary to produce stronger pigs while maintaining body condition for many future litters to come. Therefore, an elevated percentage of lactation feed should be seen as a positive indicator for your sow farm.

Examining the gestation-to-lactation feed ratio can help unearth a range of hidden issues on the farm. While it’s not a diagnostic tool for specific problems, it serves as a valuable overall indicator of sow farm efficiency. High levels of gestation feed intake can signal problems such as poor farrowing rates or an excessive number of non-productive days. Tracking G:L ratio over time can uncover insights into broad trends and seasonal issues that are sometimes difficult to identify using standard metrics.

It’s essential to consider the broader context when utilizing this metric for comparison, especially when comparing different farms. Several factors can influence the gestation-to-lactation feed ratio, including diet design, genetics, health status, parity structure, and, most notably, lactation length. For example, lactation feed intake will obviously be much higher on a farm that is weaning pigs at 28 days compared to a farm weaning at 21 days. These variables should be carefully weighed and factored in when making comparisons. The important thing is making sure sows get the nutrients they need when they need it and that should be the overriding concern.

For the reasons above, I hesitate to answer the obvious question that’s almost certainly on your mind…”what should the ratio be?” It can vary widely between farms and I think it’s more about working towards increasing lactation intake and ensuring you’re not over feeding sows in gestation. With that said, very generally, I see ratios of around 60/40 (60% gestation and 40% lactation) in higher producing farms and ratios closer to 70/30 in lower performing farms. Again, I can’t stress enough the importance of context here so make sure you work with your advisors, consultants, nutritionists and veterinarians to set appropriate targets for your farm. If you need help, feel free to reach out to us at Swine Insights, we’d be happy to help.

In conclusion, tracking the gestation-to-lactation feed ratio can provide valuable insights into the efficiency and health of your sow farm. While it may not offer precise diagnostic information, it serves as a general indication of effective feeding strategies. Furthermore, when comparing different farms within a system with similar conditions, this metric can help identify farms with an opportunity for improvement and guide efforts toward optimizing sow farm performance.

About the Author: Todd Thurman is an International Swine Management Consultant and Founder of Swine Insights International, LLC. Swine Insights is a US-Based provider of consulting and training services to the global pork industry. To learn more about the company, send an email to or visit the website at To learn more about Mr. Thurman’s speaking and writing, visit