Systems Biochemistry of Metabolic Disease Clusters in Intensively Managed Cattle Herds in Lagos and Ogun States, South West Nigeria: A Multi-Analyte Network Analysis Approach

Metabolic diseases in periparturient dairy cattle do not occur in isolation but as interconnected clusters driven by shared underlying biochemical dysregulations. A systems biochemistry network analysis approach, which examines multi-analyte interactions simultaneously rather than individual biomarkers, has not been applied to metabolic disease clustering in Nigerian dairy herds. This study applied multi-analyte network analysis to characterise the biochemical architecture of metabolic disease clusters in Friesian-Zebu crossbred cows at commercial dairy farms in Lagos and Ogun States, South West Nigeria. A cohort of one hundred and eighty cows was monitored with a sixty-analyte serum metabolic panel encompassing glucose, lipids, minerals, hormones, amino acids, and acute-phase proteins from two weeks prepartum through six weeks postpartum. Spectral correlation analysis, principal component analysis, and Bayesian network modelling were applied to identify metabolite co-variation clusters and directional biochemical interactions. Non-esterified fatty acids, beta-hydroxybutyrate, and haptoglobin formed the central hub of the primary disease cluster, mediating connections to calcium, phosphorus, and reproductive hormone derangements. A secondary cluster connecting selenium, copper, and interleukin-6 predicted immunological disease outcomes at six weeks postpartum with 79% accuracy. The network model identified pre-calving non-esterified fatty acid as the earliest divergence point between healthy and diseased trajectories, seven to nine days before clinical disease presentation. This doctoral study provides the first systems-level biochemical disease cluster framework for periparturient metabolic disease in Nigerian dairy cattle, offering novel multi-target intervention design principles. Keywords: systems biochemistry, metabolic disease clusters, network analysis, periparturient cattle, South West Nigeria.