Peripheral histamine and neonatal growth performance in swine

Identification of plasma and/or serum markers at birth that will predict animal performance may be useful for identifying animals susceptible to poor growth. Metabolomic analysis of plasma from newborn swine was used to identified potential metabolite differences between 8 pairs of littermates with similar birth weights but whose ADG differed by >50 g/d so that, at weaning (21 d), littermates differed in BW by 1.62 kg (P < 0.01). Plasma analysis failed to identify metabolic pathways impacted by growth, most likely because of the small sample population. Interestingly, despite comparative analysis of 576 metabolites between these slow-growing and normal-growing littermates, the relative abundance of only 36 metabolites differed between the pairs. Most of these metabolites could be eliminated as potential markers because of the difficulty with the extraction and rapid measurement of their plasma/serum concentrations. Histamine differed from most of these potential metabolite markers in that commercial sandwich ELISAs are readily available. Using an ELISA, we verified the metabolomic data, demonstrating that plasma histamine concentrations were 150% higher in slow-growing than normal growing littermates of similar birth weight (P < 0.05). Subsequently, a separate data set was obtained using swine from a different geographical location and genetic background and also showed that elevated histamine (ng/mL) at birth is associated with increased preweaning growth rate (P = 0.009, r = 0.306, n = 9 litters). Together, the data indicate that perinatal histamine concentrations may serve as a tool to identify potentially slower growing pigs and as a serum biomarker for predicting litter growth rate.