Influence of alfalfa protein concentrate dietary supplementation on blood parameters of growing-finishing pigs

The aim of the study was to analyse the effect of the feed additive alfalfa protein concentrate (APC), on pig health. The trial involved 40 crossbred gilts and 40 crossbred castrates (Polish Landrace × Polish Large White) × Duroc of 29.0 ± 0.5 kg initial body weight. Allocation of experimental animals was into four treatment groups: the control group (C) was fed standard mixtures, without APC addition; group E-15 was fed a basal diet supplemented with 1.5% APC; and groups E-30 and E-30P were fed diets with 3.0% APC inclusion. There were two feeding systems. In the first system, animals of groups C, E-15, and E-30 were fed continuously with suitable mixtures. The second feeding system was used in group E-30P where animals received the experimental or control mixture alternating at two-week intervals. The addition of APC supplement to diets significantly increased (P ≤ 0.05) red blood cell indices, i.e. haematocrit (Ht), red blood cell count (RBC), and haemoglobin concentration (Hb) in growing and finishing periods. The analysis of enzyme activity demonstrated a markedly higher activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and especially alkaline phosphatase (ALP) in the blood plasma of pigs fed APC supplement. This increase may indicate a negative impact of APC on the animal’s liver. A positive effect of dietary APC on blood lipid parameters was associated with a decreased level of total cholesterol and reduced low-density lipoprotein fraction. Analysis of the haematological and biochemical blood indices demonstrated that APC additive may affect animal health.