Todd Thurman, Swine Insights International
Adequate intake of colostrum is a major factor in piglet survival. Research has shown that piglets that don’t get at least a minimum dose of colostrum in the first 24 hours after birth die at rates roughly five times higher than pigs that do get sufficient colostrum. At birth, pigs have two major challenges. First, they don’t have an active immune system. This will slowly develop over time, but it will be weeks before the pig’s body can muster an immune response sufficient to respond adequately to a disease challenge. Second, newborn pigs have very little in the way of body reserves to draw upon so they are at great risk of starvation if they don’t quickly get access to an external source of nutrients, energy and protein.
It just so happens, colostrum is the solution to both problems. Colostrum, or “first milk” as it’s sometimes called, is a rich source of both nutrition and antibodies. Think of it as nature’s pre-starter in the sense that it gets pigs started on a path to good health and vigorous growth. It is also the primary source of passive immunity for the pig until it develops adequate active immunity.
If you’re thinking that colostrum is one of the most valuable substances in all of pork production, you’re right. It’s also limited and difficult to measure. Research has indicated that colostrum production is highly variable (with estimates ranging from 1 kg to 7 kg in some studies) and the supply does not appear to vary in relation to litter size. As a result, it’s reasonable to assume that, especially in large litters, colostrum is a precious commodity, likely limited and perhaps severely so.
The minimum amount of colostrum required per pig appears to be about 200 grams, but significant additional benefit up to 300 grams has been documented. So, for a litter of 12 live born pigs, 2.4 kg is required to meet the minimum requirements and 3.6 kg to supply optimum performance. Increasing the litter size to 16 increases the requirements to 3.2 and 4.8 kg respectively.
Of course, this assumes that every pig consumes an equal amount of colostrum which obviously doesn’t happen. Bigger, stronger pigs tend to consume more while smaller, weaker pigs consume less. Keeping in mind that the range of colostrum production is 1-7 kg and assuming the average sow produces ~3.5 kg, it is likely that if litters are over 12 live born pigs, there is a shortage of colostrum for optimum production. Increasing the litter size to 16 means that close to half of sows are not producing sufficient colostrum to meet even minimum requirements and very few sows are producing enough for optimum performance.
It turns out that unlike some other livestock, sows are difficult critters to milk for a variety of reasons. As a result, we simply don’t know how much colostrum they produce. With milk production, we can use proxies, such as piglet or litter growth rate, to measure milk production with reasonable accuracy, but these measurements are imperfect, subject to milk demand variation and they don’t necessarily correlate with colostrum production.
This is obviously a challenge for management. Anything that is important but you can’t measure accurately, is a problem. It is an even bigger problem in genetic selection and nutrition research. Can we select for high colostrum production? Presumably we could if we could measure it. Additionally, it seems there’s ample reason to believe there is more than enough variation which is great for genetic selection. Reproductive traits don’t tend to be highly heritable so it may take some time, but we’ve certainly had success in other metrics. All that is missing is an accurate and affordable way to measure colostrum production.
The lack of ability to measure colostrum production is also a problem for nutritionists who are interested in better understanding how nutritional strategies can impact colostrum production. Perhaps there are opportunities to adjust nutrient levels in gestation and/or gilt development diets that could positively impact colostrum production? There are some compelling reasons to believe that may be the case, but unless we have a way to measure colostrum, we won’t know for sure.
To date, research on colostrum production in sows has mostly utilized a method of estimating production by observing suckling pigs and estimating consumption levels based on time at the teat. This method is certainly better than nothing, but it is much more effective at identifying pigs that did not get sufficient colostrum than confirming the accurate intake of all pigs and it is not effective at all in determining colostrum supply independent of demand.
So, why are sows hard critters to milk? First, as a litter bearing species, they have a lot more teats to deal with. Cows have four teats but sows usually have 14 or more. Not surprisingly, sow nipples are also smaller and more difficult to grip whether stripping them manually or trying to develop a mechanical method to remove the milk.
Lastly, sow milking behavior is different from other livestock species. Sow milk is typically let down on a more frequent basis. Sows have about 30 nursing sessions per day and actual milk ejection occurs for only a matter of seconds. In contrast, cows generally have only 8-12 nursing sessions per day in the days following calving and fairly quickly go down to 4 and later sometimes only 2 sessions a day. Dairy cows can be milked only 2-3 times per day with good results. In sows, these sessions become quite regular and predictable for individual sows by the second day of lactation, but are more erratic and unpredictable in the first hours after farrowing making collecting colostrum even more difficult than collecting milk later in lactation.
So, what are the solutions? Unfortunately, there are no easy solutions. Certainly, supplemental colostrum for some or all piglets is a possible solution, but these strategies are expensive and labor intensive. Split suckling strategies are a rather obvious solution although only a partial one. Split suckling can ensure better access to suckling opportunities for weaker piglets and may result in more equitable distribution of colostrum, but it is not without risk and the impact on overall milk production is not fully understood. Neither of these solutions, however, address the root problem.
Lastly, and file this one under “easy to say and hard to do”. We need to develop a way to measure colostrum production directly or at the very least, develop a proxy measurement for colostrum production. It would be ideal if we could apply this technology at the commercial level, but if we could at least make it practical at the nutritional research and genetic selection level, it could be a total game changer.
I am aware of some capable and well-funded groups that are working on this problem and we have some reasons to be optimistic that these efforts may be successful. There is also a very real opportunity to potentially extrapolate from some of the learnings of our friends on the ruminant side. For fairly obvious reasons, much more is known about ruminant milk production. Obviously, we must be careful when extrapolating from ruminant data, however as it may not translate directly.
If anyone is looking for research ideas, I would struggle to find a more impactful, timely and relevant recommendation than this one. As I stated previously, when you have a critical metric that you are unable to measure, you have a real problem or, as the optimistic among us would say, a real opportunity.
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 info@swineinsights.com or visit the website at www.swineinsights.com. To learn more about Mr. Thurman’s speaking and writing, visit www.toddthurman.me .
