Effects of Hermetia illucens Larvae Meal and Astaxanthin as Feed Additives on Health and Production Indices in Weaned Pigs

SIMPLE SUMMARY: Weaning is a stressful period that reduces digestive capacity and increases oxidative stress and disease susceptibility in piglets. Feed additives can protect the piglets’ health status in a natural way. This study aimed to evaluate the effects of full-fat H. illucens larvae meal (HI) and astaxanthin (AST) supplementation on the growth performance and health status of weaned pigs. HI contains bioactive substances (chitin, antimicrobial peptides, lauric acid) with immunostimulatory, antimicrobial, and anti-inflammatory properties. Astaxanthin is a carotenoid pigment with strong antioxidant and anti-inflammatory capacities. The results showed that astaxanthin supports the inhibition of oxidative stress. In the experiment lasting from 35 to 70 days of age, 48 weaned pigs (about 8.7 kg body weight) were involved. Both supplements were tested separately or combined in feed mixtures. The 2.5% HI and AST supplementation can reduce the susceptibility of pork fat to oxidation. However, a higher concentration of HI (5%) was not beneficial because of the adverse changes in some of the red cell indices and thus should be combined with the antioxidant AST to improve these indices. Both supplements did not negatively affect the piglets’ productivity. ABSTRACT: Weaning is a critical period in farming, and therefore, searching for health-promoting feed additives of natural origin is necessary. This study aimed to evaluate the effects of full-fat H. illucens larvae meal (HI) and astaxanthin (AST) supplementation on the growth performance and health status of weaned pigs. The experiment was carried out on 48 pigs (8.7 kg) divided into six groups: I—control; II—2.5% HI; III—5% HI; IV—2.5% HI and AST; V—5% HI and AST; VI—AST. The experiment lasted from the 35th to 70th day of age, and animals were fed ad libitum. The results obtained indicate that HI meal and astaxanthin had no effect on feed intake and utilization, weight gain, or organ weight. Additionally, blood parameters remained within the norms. It seems that astaxanthin supports the inhibition of oxidative stress, which became apparent in the case of some red blood cell parameters. The 2.5% HI and AST supplementation can reduce the susceptibility of pork fat to oxidation (lower adipose tissue TBARS). However, 5% HI in feed was not beneficial because of the adverse changes in some red cell indices, and it should be combined with the antioxidant AST to improve these indices.