Transition cow nutrition and management strategies of dairy herds in the northeastern United States: Part II—Associations of metabolic- and inflammation-related analytes with health, milk yield, and reproduction

• Published in: Journal of dairy science 2022-06, Vol.105 (6), p.5349-5369
• Main Authors: Kerwin, A.L., Burhans, W.S., Mann, S., Nydam, D.V., Wall, S.K., Schoenberg, K.M., Perfield, K.L., Overton, T.R.
• Format: Article
• Language: English
• Subjects: 3-Hydroxybutyric Acid; Animals; Biomarkers; Cattle; Cattle Diseases; Fatty Acids, Nonesterified; Female; haptoglobin; Haptoglobins - analysis; herd-alarm level; Humans; Inflammation - veterinary; Ketosis - veterinary; Lactation - physiology; Milk - chemistry; nonesterified fatty acid; Postpartum Period; Pregnancy; Prospective Studies; Reproduction; Stomach Diseases - veterinary; transition cow; β-hydroxybutyrate
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.2021-20863

The objectives were as follows: (1) establish cow-level thresholds for prepartum nonesterified fatty acids (NEFA) and postpartum NEFA, β-hydroxybutyrate (BHB), and haptoglobin (Hp) concentrations associated with negative health events; (2) evaluate cow-level associations between biomarkers and 305-d mature equivalent milk at the fourth test day (ME305) and reproductive performance; and (3) identify herd-alarm levels (proportion of cows sampled above the critical threshold) for biomarkers that are associated with herd-level changes in disorder incidence (displaced abomasum and clinical ketosis), reproductive performance, and ME305. In a prospective cohort study, 1,473 cows from 72 farms were enrolled from the northeastern United States. Blood samples were collected from the same 11 to 24 cows per herd during the late-prepartum and early-postpartum periods. Whole blood was analyzed for postpartum BHB concentrations; plasma was analyzed for prepartum and postpartum NEFA and postpartum Hp concentrations. Critical thresholds for the biomarkers associated with health events for all cows were established using a receiver operating characteristic curve analysis. Poisson, linear mixed effects, and Cox proportional hazards models investigated the association of the biomarkers with health and performance. The prepartum NEFA and Hp threshold associated with culling was ≥0.17 mmol/L and 0.45 g/L, respectively. The postpartum NEFA and BHB thresholds associated with diagnosis of metritis, displaced abomasum, or clinical ketosis were ≥0.46 mmol/L and ≥0.9 mmol/L, respectively. Multiparous cows with prepartum NEFA concentration ≥0.17 mmol/L produced 479 kg less ME305. Multiparous and primiparous cows with postpartum NEFA concentration ≥0.46 mmol/L produced 280 kg less and 446 kg more ME305, respectively. Cows with BHB concentration ≥0.9 and ≥1.1 mmol/L produced 552 kg more ME305 and had a 20% decreased risk of pregnancy within 150 d in milk, respectively; however, multiparous cows with BHB concentration ≥1.5 mmol/L produced 376 kg less ME305. Cows with Hp concentration ≥0.45 g/L produced 492 kg less ME305 and had 28% decreased risk of pregnancy within 150 DIM. Cows with Hp concentration ≥0.45 g/L had 19% decreased pregnancy risk to first service (PRFS). Herds above the herd-alarm levels for prepartum NEFA had a 6.0-percentage unit increase in disorder incidence and a 6.0-percentage unit decrease in 21-d pregnancy rate (PR) for multiparous cows, a 3.9-percentage unit increa