Tonisity PxW Outperforms Well-known Electrolyte in US Trial
When compared to a well-known electrolyte, Tonisity PxW demonstrated noticeable performance improvements in all the parameters investigated in the study.


When compared to a well-known electrolyte, Tonisity PxW demonstrated noticeable performance improvements in all the parameters investigated in the study:

  • +22% better water intake on day one post weaning and 9% better water intake over five days post-weaning
  • +300g extra weight at the end of nursery
  • 65% fewer fall-behinds
  • 17% reduction in nursery mortality
  • 18 extra live or healthy pigs per 1,000 pigs weaned

Tonisity recently completed a trial on a high-performing gilt multiplication nursery-finish farm in South Dakota in the US. The objective was to compare Tonisity PxW, a water-soluble solution for weaned or fattening pigs, with a well-known electrolyte.

The pigs (all females) were transported for a duration of three hours from the farrowing house to the nursery location. A total of 5,665 pigs over eight production batches (500-850 pigs/batch every three to four weeks) from December 2020 to July 2021. With an average weaning age of 21 days, the pigs were given two separate treatments. Each batch was randomly split between the Electrolyte B and the PxW treatments, amounting to a total of 2,812 Electrolyte B pigs and 2,853 PxW pigs over the eight batches.

In batch one, pigs received Electrolyte B at a dose of 1lb/64 gallons (0.45 kg/242 L) of water, at a constant concentration for five days. In batch two, pigs received the recommended dose of Tonisity PxW (PxW) for five days. The two treatment groups had identical feeding regimes during the study.

Water consumption, average pig weight, the number of fall-behinds and mortality were all measured to compare the effectiveness of each solution. Water consumption was recorded for each treatment group using water meters, starting at day zero, with recordings taken on the first five days post-weaning. Pigs were weighed as whole pens, on arrival, on day 14 of the study, and on day 42 of the study (at transfer to the finishing stage). Fall-behinds or sick pigs that had to be removed from the group to hospital pens and treated were recorded as was mortality for the entire nursery period.

On day one post-weaning, the PxW pigs had an average water intake of 0.29 gallons per pig per day (1.08 litres), 22% higher than Electrolyte B group’s average 0.24 gallons per pig per day (0.89 litres).  This was a statistically significant difference, with a P-value of 0.04. The water intake advantages for the PxW group were also maintained beyond day one, stabilising at a numerical 9% advantage. This decrease was expected, since the PxW concentration was gradually decreased by 50% on days two and three, and by 75% on days four and five as part of its tapered protocol. The transition from PxW to water after five days was seamless, with no noticeable decrease in consumption after day five post-weaning.

It is widely known that weaning stress, the change from sow milk to feed and water, as well as post-weaning transport will result in the piglets becoming dehydrated. This state of dehydration can last up to one week post weaning and leads to a delay in feeding (Pluske, J. R. et al., 2003). An empty intestine, in turn, leads to local inflammation which triggers important production losses and predisposes weaner pigs to disease. By having a higher water consumption in the current study, especially from day one post-weaning, the PxW pigs also availed of Tonisity PxW’s key gut-health enhancing bioactives, meaning that the intestinal function was supported, and they were ready to consume solid feed. Indeed, because of this the PxW pigs exhibited better growth performance throughout nursery.

The starting weight for both groups were the same to begin with, but the PxW pigs had an average end-nursery weight of 48.71lb (22.1kg), being 0.65lb (300g) heavier than Electrolyte B group’s average end-nursery weight of 48.06lb (21.8kg). This difference had a P value of 0.17, based on the average pig weights for 140 pens of pigs. This weight advantage largely appeared after the two-week weighing point. This confirms that the initial bioactive boost for the PxW group, coupled with adequate post-weaning hydration, has long-lasting beneficial effects on pig growth. This is despite Electrolyte B also having acidifying properties.

The mortality at nursery in the PxW group was 0.95%, 0.2 percentage points lower than Electrolyte B group’s mortality of 1.14%. This represents a 17% reduction with a P value of 0.28. While the mortality is very low on this high-health farm, this reduction amounts to two extra pigs/1000 weaned at the end of nursery.

There were 0.7% fall-behinds in the PxW group, 1.3 percentage points lower than Electrolyte B group’s average of 2%, representing a 65% reduction, with a highly significant P value of P<0.0001. The lower percentage of fall-behinds amounts to 13 fewer fall-behinds/1000 weaned. Fall-behinds require individual treatments and room space, a reduction in fall-behinds decreases workload and the cost of production.

The strength of this study comes from the fact that all the monitored performance parameters were in favour of Tonisity PxW, albeit not all of them being statistically significant. However, this statistical significance would be reached over time in regular large-scale production.

For a multiplication farm, this potentially means 18 extra gilts that can go to the market as high value animals, instead of fall-behinds that would need to be sold as fatteners. At the current market prices, this means an extra value of minimum €3,000, for an investment of only €200 (€0.20 per pig). For the genetic company, this also means less complaints about the quality of the gilts sold, and more royalties paid by the multiplication farm.

Providing Tonisity PxW to pigs post-weaning ensures a quick start on water, followed by feed intake, resulting in long-term body weight and health improvements to the end of nursery. We have seen in our Tonisity PxW 31,861-pig meta-analysis a 70% better water intake, a 57% reduction in nursery mortality, and a 41% reduction in fall-behinds in nursery.

Other Useful Resources
Supporting Pigs Through Heat Stress
Pigs are a particularly vulnerable to heat stress as a species because they have a limited ability to cool themselves...
Porcine Respiratory and Reproductive Syndrome (PRRS)
Another wave of PRRS is sweeping across North America. A new and more infectious strain of the virus is leading...