The effect of an acidifier on the growth performance and haemolytic Escherichia coli level in pigs during the post-weaning period. (Short Communication)

Abstract

21A THE EFFECT OF AN ACIDIFIER ON THE GROWTH PERFORMANCE AND HAEMOLYTIC E. COLI LEVEL IN PIGS DURING THE POST-WEANING PERIOD R.J. JOHNSON* AND R.G. CAMPBELL** Young pigs have a physiological deficiency in gastric hydrochloric acid production (Kidders and Manners, 1978) and certain dietary ingredients exasperate this condition because of their high buffering capacity. This failure to attain a sufficiently low stomach pH in the young pig may contribute to growth reduction and an increase in the incidence of scours in the immediate postweaning period. Addition of certain organic acids to the diet of pigs have been shown to have beneficial effects on growth and to reduce the incidence of haemolytic E. coli (Cole, 1968). The present study investigated the use of a commercial acidifier, Acid-Pak 4-Way (Alltech Inc. Kentucky, U.S.A.), which contains acidifiers, feed enzymes, a direct-fed microbial, flavours and electrolytes. The experiment was a 2 x 2 factorial with two levels of Acid-Pak-4-Way (AP4W) added to the drinking water (0 and 1 g/l) and two levels of whey powder (0 and 80 g/kg) added to a conventional pig weaner diets. The two control treatments (no whey powder or AP4W) had 4 replicates while the other treatments had 8 replicates. Each replicate contained 32 pigs with equal numbers of males and females. Pigs were weaned at approximately 21 d of age and the treatments were applied over the following 25 d. Growth performance and the excretion of haemolytic E. coli were measured. Results are given in the Table. TABLE 1 Growth performance and haemolytic E. coli excretion in pigs in the post-weaning period given a commercial acidifier (Acid-Pak 4-Way) in the drinking water with and without dietary whey powder + There were no significant effects of treatments on growth rate, although AP4W and whey increased growth rate by about 8 and 6% respectively. Similarly both AP4W and whey tended (0.05 < P< 0.10) to increase feed intake. There was some indication (not significant) that this effect only occurred with AP4W and whey in the diet. There was a significant reduction in haemolytic E. coli faecal excretion rate with the addition of AP4W to the water when the diet contained whey. These results indicate that the commercial acidifier tested (Acid-Pak 4-Way) may have considerable benefits in improving growth and reducing the possibility of E. coli scours in young pigs. Cole, D.J.A. (1968). Vet Rec. 83:459-464 Kidder, D.E. and Manners, M .J.(1978). Digestion in the pig. Scientechnica. Bristol. * ** Rhone Poulenc Animal Nutrition, 19-23 Paramount Road, West Footscray, Victoria, 3012. Bunge Meat Industries, 174 Hume Street, Corowa, NSW, 2646