Evaluation of dietary l-carnitine or garlic powder on growth performance, dry matter and nitrogen digestibilities, blood profiles and meat quality in finishing pigs

The effects of dietary l-carnitine or garlic powder supplementation on growth performance, coefficient of total tract apparent digestibility (CTTAD) for dry matter and nitrogen (N), blood profiles and meat quality were investigated in a 10-week feed trial. A total of 80 [(Landrace × Yorkshire) × Duroc] pigs with an initial body weight (BW) of 59 ± 1.8 kg were randomly assigned to four dietary treatments with five replications per treatment and four pigs per pen. A maize–soybean meal-based diet was formulated as a control diet and other treatment diets were supplemented with 250 mg l-carnitine/kg and 1 g garlic powder/kg or 2 g garlic powder/kg, respectively. After the feeding period, meat samples were collected from those pigs, which reached market body weight (BW). During the feeding period, growth performance was not affected by dietary treatments. CTTAD for both DM and N were improved by supplementation of 1 g garlic powder/kg (P<0.05). White blood cell (WBC) and lymphocyte concentrations were increased by l-carnitine addition at the end of experiment whereas garlic powder supplementation did not affect any tested blood profiles. Backfat thickness was decreased and muscle percentage was increased by the l-carnitine supplementation (P<0.05). Pigs administrated with 1 g garlic powder/kg had better meat colour, pH value and water holding capacity (WHC). In conclusion, dietary supplementation of l-carnitine (250 mg/kg) can increase WBC and lymphocyte concentration and decrease backfat thickness, while garlic powder supplementation at the level of 1 g/kg can improve CTTAD and meat quality in finishing pigs.