A Comparison of Haematological and Biochemical Profiles between Intrauterine Growth Restriction and Normal Piglets at 72 Hours Postpartum

SIMPLE SUMMARY: In recent years, the pig industry has focused on genetic selection based on prolificacy. However, this has resulted in heterogeneous litters, more low-birth-weight piglets, and an increase in the incidence of piglets being born with intrauterine growth restriction (IUGR), decreasing the survival rate. Thus, the aim of this study was to advance the haematological and biochemical knowledge of IUGR piglets in the first days of life and evaluate their possible changes compared to normal piglets. At 72 h of life, we found differences in the parameters studied. IUGR piglets showed changes in red and white blood cells, reticulocytes indices, and some biochemical parameters, which indicated immaturity. The results provide information on the analytical profile of IUGR piglets and suggest that the divergence of the two groups of piglets is evident a few hours after birth. ABSTRACT: Intrauterine growth restriction in piglets has been a problem in the pig industry due to genetic selection based on hyperprolificacy. This has led to an increase in the number of underweight piglets and a worsening of the survival rate. The goal of this study was to enhance the knowledge of differences between normal and IUGR piglets a few hours after birth in terms of haematological variables, biochemical parameters, and immunoglobulin levels. Two groups of 20 piglets each were assessed. The control group (N) was made up of piglets with weights greater than 1500 g, and the IUGR group consisted of piglets weighing 500–1000 g and with at least two IUGR features. Blood samples were collected 72 h after birth for analysis of the red and white blood cell parameters, reticulocyte indices, platelet indices, biochemical parameters, and immunoglobulin levels. Alterations in red blood cells and reticulocytes, a lower lymphocyte count, hyperinsulinemia, and high oxidative stress were observed in IUGR piglets (p < 0.05). In contrast, differences were not observed (p > 0.05) in the serum immunoglobulin level. It can be concluded that the haematological and biochemical differences in IUGR piglets with respect to normal-weight piglets are present at birth indicating possible alterations in immunity, metabolism, and redox status; therefore, IUGR piglets could be more vulnerable to illness and future disorders, such as metabolic syndrome.