Aarhus University Seal / Aarhus Universitets segl

Leslie Foldager

Random forests prediction of blood metabolic clusters by milk metabolites and enzymes in dairy cows

Publikation: Bidrag til bog/antologi/rapport/proceedingKonferenceabstrakt i proceedingsForskningpeer review


Milk biomarkers as predictors of physiological imbalances and subclinical or clinical diseases in dairy cows may be used in management and selection. The objective was to use milk metabolites and enzymes to predict three clusters differentiating the metabolic status of cows and defined by clustering of plasma hormone Insulin-like Growth Factor-1 (IGF-1) and three plasma metabolites: Glucose, beta-hydroxybutyrate (BHB), and non-esterified fatty acids (NEFA). Data between calving and 50 days in milk (DIM) were obtained from 209 Holstein Friesian cows in six research herds: AU (Denmark), UCD (Ireland) AFBI (UK), CRA-W (Belgium), FBN (Germany), CREA (Italy). Some diets were designed to challenge the cow and provoke production diseases but there were too few incidences to establish predictors of clinical and subclinical diseases. Instead, k-means clustering was performed over scaled residuals from linear mixed effects models for each of IGF-1, Glucose, log10(BHB) and log10(NEFA) measured around 14 and 35 DIM. Each milk metabolite (free glucose, glucose-6-phosphate, BHB, isocitrate, uric acid, urea) and enzyme (LDH, NAGase) from 2 milkings/week was averaged within week and matched with blood sampling. Random forests (RF) predictions with milk markers and parity (1, 2 and 3+) was evaluated by leave-one-cow-out (internal) cross-validation. Overall accuracy: 0.52 (95% CI: 0.45-0.59) on DIM14 and 0.44 (0.37-0.51) on DIM35. Sensitivity for each cluster: (0.77, 0.87, 0.61) on DIM14 and (0.65, 0.71, 0.79) on DIM35. Specificity: (0.54, 0.34, 0.61) and (0.46, 0.51, 0.32). We obtained predictions of metabolic clusters from milk biomarkers of fair accuracy. Sample sizes may constraint both estimation of clusters, number of classes, and RF training. External validation in separate herds is warranted. Still, we see potential in using milk biomarkers to support management of dairy cows.
TitelBook of Abstracts of the 68th Annual Meeting of the European Federation of Animal Science
UdgivelsesstedThe Netherlands
ForlagWageningen Academic Publishers
ISBN (trykt)978-90-8686-312-9
ISBN (Elektronisk)978-90-8686-859-9
StatusUdgivet - 2017
Begivenhed68th Annual Meeting of the European Federation of Animal Science : EAAP - Nordea Concert Hall, Tallinn, Estland
Varighed: 28 aug. 20171 sep. 2017


Konference68th Annual Meeting of the European Federation of Animal Science
LokationNordea Concert Hall
SerietitelBook of Abstracts of the Annual EAAP Meeting

Se relationer på Aarhus Universitet Citationsformater


ID: 120130784