Immune and parasitic response to conjugated linoleic acid in the diet of pelibuey sheep infected with gastrointestinal nematodes

Abstract

The aim was to evaluate the immune and parasitic response of Pelibuey sheep infected with gastrointestinal nematodes (Haemonchus contortus, GIN) and supplemented with conjugated linoleic acid (CLA). Twenty-four Pelibuey male lambs were distributed into one of four groups of six animals, placed in individual pens, in a completely randomised design, allotted to four treatments as follows: T1) No larval challenge without CLA (control group); T2) Larval challenge without CLA; T3) Larval challenge and 1% CLA; and 4) Larval challenge and 3% CLA. All the lambs were on grazing conditions before the experimental period. The haematologic, immune, parasitic and productive responses were evaluated. Total leukocytes, lymphocytes and eosinophils were different between treatments (p ≤.05), but not granulocytes (p >.05). Haematocrit (HCT), and red blood cell count (RBC) decreased (p ≤.0001), while mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) increased in infected lambs supplemented with CLA, and mean corpuscular volume (MCV) increased with respect to control lambs. Haemoglobin (HGB) was the only variable that was not different between treatments (P = 0.113). The faecal egg count (FEC), plasma protein (PP), and immunoglobulin G (IgG) and immunoglobulin M (IgM) levels were not modified among treatments (p >.05). Daily weight gain was not different between treatments (p >.05). Supplementing Pelibuey lambs with conjugated linoleic acid did not modify their immune response, nor did the parasitic infection, but it did affect the blood parameters. The nutritional factor had an essential role in such response.Highlights New alternatives in parasitic control in sheep Conjugated linoleic acid modulates the immune response in sheep Nutritional factor could be an excellent control mechanism against parasitic infections.