Efficacy of an automated technology at detecting early postpartum estrus events: Can we detect resumption of cyclicity?

• DOI: 10.3168/jdsc.2023-0463
• Publication Date: 2023-11-17T21:28:12Z
• Authors: S. Borchardt; T.A. Burnett; W. Heuwieser; J.L. Plenio; R.S. Conceição; R.L.A. Cerri; A.M.L. Madureira
• Keywords: postpartum estrus events; Landwirtschaft und verwandte Bereiche; Physiology; SF250.5-275; 630; Dairy processing. Dairy products

The objective of this observational study was to evaluate the efficacy a neck-mounted automated activity monitor (AAM) at detecting early postpartum resumed ovarian cyclicity. A total 192 lactating cows (primiparous = 73 and multiparous 119) were enrolled in study. Cows continuously monitored by AAM (7 30 d milk; DIM). Calving classified as assisted (forced extraction calf) or unassisted (normal calving). Retained fetal membrane, metritis, hyperketonemia, clinical mastitis, milk production recorded. healthy (i.e., no disease events) sick any event). Estrus events alerted using proprietary algorithm set company. Blood samples, from coccygeal vein, collected 15, 18, 21, 24, 28, DIM for progesterone (P4) analysis. Resumption cyclicity considered when P4 concentration ≥1 ng/mL on collection day. anovular <1 all days. true positive: ≥ 1 least one estrus alert; false < negative: alerts; alerts. Statistical analyses performed frequency distribution mixed effects logistic regression procedures SAS (SAS Institute Inc.). specificity, sensitivity, accuracy, positive predictive value sensor detect that had 84.0%, 34.1%, 52.1%, 79.2%, respectively. Out cows, 35.9% (69/192) anovulatory 37.5% (72/192) between 7 DIM. Healthy more likely resume lactation compared with (78.3 ± 1.9 vs. 32.8 3.1%, respectively) independent parity. In conclusion, high specificity but it lower thus not effective cyclic perhaps due silent ovulation postpartum.