Microencapsulated acids associated with essential oils and acid salts for piglets in the nursery phase

The objective of this study was to evaluate the use of commercial blends of organic and inorganic acids combined with essential oils for piglets in the nursery phase. The formulations were administered as microcapsules or as acid salts. Ninety-six, Pen Ar Lan, barrow and female piglets, weaned at a body weight of 600 kg +/- 12 kg and age of 23 days were subjected to four treatments. The animals were distributed in randomized blocks of three animals per pen and 8 replicates per treatment. The treatments consisted of four different diets: control (free of organic acids); acid and essential oil blends (fumaric acid 10,5%, malic acid 8.0%, essential oils; in microencapsulated form); microencapsulated acid blend (phosphoric acid 10%, citric acid 10%, malic acid 10%, fumaric acid 20%; in microencapsulated form); and acid salt blend (formic acid 40.5%, phosphoric acid 13.6%, propionic acid 4.9% and salts (23.2% calcium and 4.4% phosphorus available). The performance parameters, digestive transit time, weights of organs of the digestive tract, bacterial count of feces (Lactobacillus, E coli and Salmonella ssp and Clostridium), pH of the stomach and duodenal content did not differ between treatment groups (P> 005). All treatments containing organic acids exhibited positive effects on diarrhea control (P < 005). The cecal contents of volatile fatty acids (VFA) were higher in piglets fed diets containing acids than in animals that received the control diet (P < 005), and blends containing essential oils improved the jejunum villus height compared with the control group. The use of diets containing acids improved diarrhea control and VFA production in the cecum, and specifically the diets containing microencapsulated acid blends required the lowest doses to be effective.