Isoquinoline alkaloids and naringin improve apparent ileal digestibility and growth performance in post-weaning piglets

Appropriate nutrient digestibility is a key to animal health and growth performance, particularly in post-weaning pigs. Compounds with anti-inflammatory or anti-oxidative properties have potential to support gut integrity and growth performance when included in diets for pigs. Isoquinoline alkaloids (IQ) derived from the Papaveraceae plant Macleaya cordata exert anti-inflammatory effects, whereas naringin (NRG), a bitter-tasting flavanone glycoside from citrus fruits has anti-oxidative properties. Aim of this study was to determine the effects of IQ or NRG on digestibility and growth performance of post-weaning piglets.

Fifty-six barrows and female post-weaning piglets (Danbred, Denmark) with an average initial body weight (BW) of 6.39 ± 0.4 kg and weaned at 25 ± 2 days of age were selected for this 6-wk feeding experiment. Piglets were assigned to 4 treatments according to BW, litter, and gender with 7 replicate pens and 2 piglets per pen. Treatments were 1) Control (basal diet), 2) IQ-1 (basal diet + 60 mg IQ/kg), 3) IQ-2 (basal diet + 120 mg IQ/kg), 4) NRG (basal diet + 50 mg NRG/kg). IQ were provided using a commercial product (Sangrovit® Extra, Phytobiotics Futterzusatzstoffe GmbH, Eltville). Piglets had ad libitum access to mash feed and drinking water.

Piglets were fed a starter (25-38 days of age) and grower diet (39-66 days of age) based on corn, soybean meal, wheat and barley. Faecal scores and growth performance were determined weekly. Apparent ileal digestibility (AID) on day 66 days of age was determined using TiO2 (5 g/kg) as an indigestible marker using one piglet per pen.

Weekly faecal scores did not differ between treatments (p> 0.05), indicating no major health issues. IQ-1, IQ-2 and NRG improved weight gain in the first two weeks of the experiment (p< 0.05), whereas FCR was improved in the entire experimental period (Control: 1.47, IQ-1: 1.43, IQ-2: 1.40, NRG: 1.42; p< 0.001). In addition, overall weight gain was highest and different from the Control in pigs fed NRG (p=0.023). Compared to the Control IQ-2 improved (p< 0.05) AID of protein, phosphorus (P) and total and various single amino acids, whereas NRG increased (p< 0.05) AID of P, alanine, aspartic acid and leucine.

Supplementation of diets with IQ and NRG increased amino acid digestibility, indicating an increased capacity for nutrient absorption in postweaning piglets. Increased digestibility was reflected in improved feed efficiency. As such, IQ and NRG represent tools to support gut integrity and growth performance in piglets.

Disclosure of Interest: None Declared.