Animal (Sep 2022)
The amino acid profile of Camelina sativa seeds correlates with the strongest immune response in dairy ewes
Abstract
Camelina sativa is an alternative protein source (with a specific amino acid profile) rich also in bioactive compounds (such as polyunsaturated fatty acids and antioxidants), which have immunomodulatory properties. This study aimed to assess the impact of the dietary inclusion level of Camelina seeds, on the expression levels of key genes involved in ewes’ innate immunity. Forty-eight dairy ewes were assigned into four homogenous groups of 12 animals that were fed individually with alfalfa hay, wheat straw, and concentrate. The concentrate of the control group (CON) had no Camelina seeds, while in the treated groups, Camelina seeds (CSs) were incorporated at 6 (CS6), 11 (CS11), and 16% (CS16) in the concentrates, respectively, as partial substitution of both soybean meal and maize grain. The relative transcript levels of the immune-related genes were determined using a real-time PCR platform. The relative transcript levels of toll-interleukin receptor-domain-containing adapter-inducing interferon-β, tumour necrosis factor receptor-associated factor 3, Interferon regulatory factor 5, and Mitogen-activated protein kinase were upregulated in monocytes of the CS11-fed ewes. Furthermore, in the CS6-fed ewes, the relative transcript levels of Interleukin-1 beta (IL1B) were upregulated in monocytes compared to the CON, while those of IL1B, Interleukin-8, and Interleukin-10 were upregulated in neutrophils compared to the CON and the CS11-fed ewes. The highest inclusion level of CS (CS16) did not have a negative impact on ewes’ innate immunity. The response of monocytes on dietary amino acid (mainly threonine, tyrosine, serine, and lysine) changes related to Camelina inclusion is different from that of neutrophils. The observed responses need to be further investigated.