Effect of prepartum lying time on stillbirth in transition dairy heifers and cows

A. GARCIA-GUERRA; M. PIÑEIRO; G.M. SCHUENEMANN; A.A. BARRAGAN; A. E. RELLING; B.T. MENICHETTI

Knoxville

Congreso; 2018 American Dairy Science Association® Annual Meeting; 2018

change-newline">The objective was to assess the effect of prepartum lying time (LT) onstillbirth in transition dairy heifers and cows. A total of 1,051 Holsteindairy cows (401 primiparous and 650 multiparous) from 3 commercialdairy herds were enrolled at 14 d before calving until 14 d post-calving.Weekly, a cohort of 10 to 15 cows was enrolled at each farm and electronic data loggers (IceQube, IceRobotics, Edinburgh, UK) were fitedto the hind leg of individual cows to assess their lying time. All heifersand cows were housed in similar prepartum freestall barns and movedinto a contiguous individual maternity pen for parturition. Stillbirthwas defied as a calf born dead or died within 24 h after birth, and withnormal gestation length. Blood samples were collected at 7 d before(dpp) and at calving to assess NEFA and calcium (Hypocalcemia ≤ 0.8mg/dL), respectively. Data were analyzed using MIXED procedure ofSAS. Multiparous cows had greater (736 ± 20 min; P < 0.05) LT beforeparturition compared with primiparous cows (597 ± 30 min). Multiparous cows with a stillborn calf had reduced pre-partum LT (716 ± 28min; P < 0.05), increased NEFA 7 dpp (416 ± 44 µEq/L) and increasedhypocalcemia (56.7 ± 11%) at calving compared with cows with a calfborn alive (762 ± 12 min, 313 ± 8 µEq/L, and 33.6 ± 6%, respectively).Primiparous cows with stillborn calf had reduced LT (570 ± 35 min) andincreased hypocalcemia (45.4 ± 15%) at calving (P < 0.05) but NEFAdid not differ compared with primiparous cows with a calf born alive(625 ± 25 min and 18.7 ± 9%, respectively). These results suggest thatLT, prepartum energy status, and calcium at calving of dams are criticalfor calf survival.