Three 28-day experiments were conducted to determine the effects of dietary acidifiers on the growth performance of nursery pigs housed under both university and field conditions, according to J.E. Nemechek and colleagues. All diets were corn-soybean meal–based and fed in meal form.

Each experiment consisted of a two-phase diet series with decreasing nutrient concentrations in the second phase.

The same four dietary treatments were evaluated in all three experiments, including a control with:

1. no acidifier
2. 0.5 per cent Vevovitall (DSM Nutritional Products, Parsippany, New Jersey)
3. 0.2 per cent Kem-Gest (Kemin Americas, Des Moines, Iowa), or
4. 0.05 per cent Buti-Pearl (Kemin Americas).

In Experiment 1, 280 weanling pigs (PIC 327 × 1050, initially weighing 16.1 lb, three days post-weaning) were used with seven pigs per pen and 10 pens per treatment.

From days 0 to 14, pigs fed the Kem-Gest diet tended to have a higher (P<0.07) average daily gain than pigs fed the other three treatments. From days 14 to 28 and for the overall data (days 0 to 28), no differences (P>0.64) were observed in average daily gain, average daily feed intake or feed:gain ratio among treatments.

In Experiment 2, 1,728 nursery pigs (PIC 327 × 1050, initially weighing 12.8 lb, 10 days post-weaning) were used with 48 pigs per feeder (24 pigs per pen) and nine feeders per treatment. Treatment diets were fed from days 0 to 14, and a common diet was fed from days 14 to 28.

From days 0 to 14, pigs fed the control diet had lower (P<0.001) average daily gain and poorer (P<0.001) feed:gain ratio than pigs fed diets with acidifiers. From days 14 to 28, when a common diet was fed, there were no differences (P>0.60) in average daily gain, average daily feed intake or feed:gain ratio among treatments.

Overall (days 0 to 28), there were no differences in average daily gain, average daily feed intake or feed:gain ratio (P>0.11) but pigs fed diets containing acidifiers were approximately 2 lb heavier at the conclusion of the trial.

In Experiment 3, 1,800 nursery pigs (PIC 327 × 1050, initially weighing 16.3 lb, 13 days post-weaning) were used with 50 pigs per feeder (25 pigs per pen) and nine feeders per treatment.

Treatment diets were fed throughout the entire trial (days 0 to 28) but there were no differences (P>0.12) in average daily gain, average daily feed intake or feed:gain ratio among pigs fed the different dietary treatments from days 0 to 14, days 14 to 28 or for the overall trial.

Overall, the responses to dietary acidification were inconsistent across experiments but the reasons are unclear, concluded Nemechek and co-authors. Pigs fed acidifiers had improved growth performance in Experiment 2 but not Experiments 1 and 3.

They added that further research is needed to determine the reason for the inconsistent responses so dietary acidifiers can be used effectively to improve the performance of nursery pigs.

Reference

Nemechek J.E., M.D. Tokach, S.S. Dritz, R.D. Goodband, J.M. DeRouchey and J.R. Bergstrom. 2013. Evaluation of dietary acidifiers on growth performance of nursery Pigs. Proceedings of 2013 Kansas Swine Day, p49-58.

February 2014