Effect of purified docosahexaenoic acid supplementation on production performance, meat quality, and intestinal microbiome of finishing pigs

This study examined the effects of docosahexaenoic acid (DHA) purified from fish oil on the growth performance, nutrient digestibility, faecal microbial count, faecal score, and meat quality of finishing pigs. A total of 160 crossbred finishing pigs [(Yorkshire × Landrace) × Duroc] with an average body weight of 70.51 ± 2.23 kg were randomly assigned to 1 of 4 diets [5 pigs per pen (2 barrows and 3 gilts); 8 pens per treatment]. Dietary treatments were: CON – basal diet, TRT1 – CON + 0.10% DHA, TRT2 – CON + 0.25% DHA, TRT3 – CON + 0.50% DHA. DHA supplementation resulted in a linear increase ( P = 0.046) in final body weight of finishing pigs. DHA supplementation increased average daily gain (ADG) in the TRT3 group compared to the CON group at week 6. In addition, the gain to feed ratio (G:F) was increased in the TRT3 group compared to the CON group. Increasing dietary DHA levels linearly improved ADG ( P = 0.046) and G:F ( P = 0.021). DHA supplementation did not influence nutrient digestibility. The pH, water holding capacity, cooking loss, and meat colour were not affected by the supplementation with graded DHA levels. On day 7, drip loss was reduced in the TRT2 and TRT3 groups compared to CON. However, faecal microbial and faecal score measurements remained unaffected among the treatments. In short, powdered DHA supplementation improved growth performance in finishing pigs without affecting nutrient digestibility, intestinal microorganisms and faecal score.