Disease challenges eat into time and profits, and are all too common on US pig farms. That is one reason some producers are switching to batch farrowing as a way to break the disease cycle, Clayton Johnson, DVM, with Carthage Veterinary Services, told Pig Health Today.

Whether due to health issues in the sow herd, a bad scour in the farrowing house or perhaps a recurring disease on the farm, batch farrowing may help a farm recover more quickly, Johnson said.

“You also have producers with sow farms that may be 20 or 30 years old. Sow farms were smaller when we built them back then, and their wean-to-finish farms have gotten much bigger with time,” he added.

Small farms have a harder time filling the bigger wean-to-finish farms in a short period of time. These producers are batching to decrease the fill time on their wean-to-finish space and use the space more efficiently.

Old practice is new again

Batch farrowing used to be the most common production style for farms that were farrow-to-finish, Johnson said.

“We were somewhat forced into a batch-farrowing model because we were constrained by space…at weaning time,” he explained. “Our nurseries were always full with the last batch of weaned pigs, so until those nurseries were able to move up into the grower and the grower into the finisher, we didn’t have any space to wean the pigs.”

It was a “natural batch” system that led to some stability from the endemic pathogens that were common at that time. As the industry deals with increasingly complex pathogens such as porcine reproductive and respiratory syndrome (PRRS), porcine epidemic diarrhea (PED) virus or influenza, producers have shown interest in moving back to batch farrowing and its all-in, all-out concept which leads to a healthier pig portfolio at weaning, he said.

Where to begin

When it comes to eliminating disease, the producer’s goal is generally to tackle the farrowing house last, as adult animals tend to stabilize to disease more quickly than neonates.

“If we have a disease outbreak of PRRS or PED, our main focus early on is homogenizing the exposure to the sows in the sow farm,” he said. “If we can get the adults healthy, then we can tackle the farrowing house as our last push to get the pathogen out of the farm.

“Batch farrowing lends itself to allowing you to have an all-in, all-out farrowing house,” Johnson continued. “That makes it easier to take the final leap in the elimination process and get disease out of the farrowing house, because you don’t have to eliminate the pathogen with little pigs still present on the site.”

Newborns are born naïve to most diseases, and therefore they’re susceptible, Johnson said. If there are infected pigs in the farrowing house, it can become a snowball of infections.

“Batch farrowing gives you an all-in, all-out option,” he added. “If I clean up my farrowing house, and as long as my sows aren’t infected and actively shedding, the next time I have a batch of baby pigs in the farrowing house I should be able to keep them negative, because there are no other infected pigs on the site at that point to share the pathogen with new baby pigs.”

Consider the overall value proposition

Batch farrowing can result in aa positive net-value proposition for many producers, but it’s important they calculate how many pigs they would produce on a batch model compared to continuous production to understand if the system is indeed more economical.

“If you’re in continuous production today, you can use that existing performance as a baseline to say, ‘Okay, if I have to batch, how does my PSY [pigs per sow per year] change? How do I expect my post-weaning performance to change?’

“That’s where batch farrowing is going to shine for most producers,” Johnson said. “They hopefully have better growth, which means increased average daily gain; better efficiency, if they have fewer health challenges; and lower mortality.”

With these assumptions, producers should be able to calculate overall pounds of pork produced out of their production system. For some, the cost may be higher, but if they have improved production, they’re increasing the overall throughput, and hence, may be able to justify the increased cost, Johnson said.

Potential negatives to batch farrowing

While there are benefits to be gained, producers do need to consider unintended consequences a switch to batch farrowing could have, Johnson added.

“You’re going to gestate more days in your farrowing crates on a batch model than you do in a continuous production,” he said. “Continuous production lets us be nimble with the farrowing house and turn those animals over on a row-by-row if not room-by-room basis.”

With batch farrowing, animals are loaded into the farrowing house earlier than they would be in a continuous-production system.

“In continuous production you can target day 112 or day 113 of gestation as your drop-dead date…to minimize the number of days they’re gestating in the farrowing house,” he continued. “If you want to batch, you have to load the first animals that are due on day 112 or day 113, plus all the other cohorts from that breed group that may be earlier in their gestation cycle.”

Animals will gestate in the farrowing crates for longer, which will decrease the throughput of the farrowing crates and impact overall production.

Different batch models provide options for throughput in terms of the wean age or litters per sow per year, for example, so Johnson said it’s important to consider long-term implications.

“As litters per sow per year come down, so will your pigs per sow for a year, and decreased PSY is something producers are going to think long and hard on before they [switch],” Johnson said. “You have batch model options that will optimize your litters per sow per year and as such, optimize your PSY, but those come with a consequence to wean age. You have other batch model options that optimize your wean age, but at a consequence to your PSY. Ultimately, producers will have to choose what’s more valuable to their operation, more pigs or higher wean age.”

Change in workflow

The change in system can also result in changes to workflow, with certain tasks condensed into shorter periods in batch systems.

For example, as the weeks are concentrated into a batch, the employee team’s flexibility is minimized, Johnson said. A 5-week batch program requires 5 weeks of breeding, 5 weeks of farrowing and 5 weeks of weaning, and it all needs to happen during a set period.

Staff either need to be rotated across multiple farms or cross-trained to handle a variety of tasks during different periods.

“If you only have one farm and one team and your turnover rate is high, you may have to look at batches like 10-2, where you’re concentrating 2 weeks’ worth of animals into 1 week. That’s a little more forgiving from a labor standpoint,” he added.

Pre-planning is key

Before making a decision, producers need to consider all the available models of batch farrowing to understand the pros and cons for their particular system, Johnson recommended.

“The transition from continuous production to batch production is a hard one,” he said. “There’s a lot of work to be done. You want to make sure that when you switch, you switch to the right one [for your system].”

If a producer doesn’t understand batch models well enough to map out their pig flow, Johnson suggested they talk to their veterinarian or production consultant.

“Work with somebody who has a lot of experience with a batch to lay all that out for you…and you can select the one that works best for you,” he said.