282 Nutritional Monitoring of Prenatally Stressed and Translocated Brahman Heifers Academic Article uri icon

abstract

  • Abstract One drought mitigation strategy is transporting livestock to non-drought locations. Our objective was to evaluate the effects of prenatal stress and translocation on growing Bos indicus heifers. Twelve heifers born in spring 2019 at Overton, TX (1245 mm annual precipitation) were transported ~700 km to Sonora, TX (610 mm annual precipitation) in April 2020. Six heifers (28310 kg) were born to dams subjected to transportation stress during mid-gestation (PNS) and 6 (27917 kg) were born to non-stressed dams (CON). Heifers grazed a series of 24-ha native range pastures (aboveground forage biomass; 1508390 kg/ha) and were sampled (non-shrunk BW/BCS score, feces) at 2-wk intervals from May through September. Fecal samples were collected from the ground or the rectum of each animal and stored at -20o C until processed for near infrared spectroscopy (NIRS) and prediction of diet crude protein (CP) and digestible organic matter (DOM). Inputs to a grazing animal nutrition model for prediction of BW included diet CP and DOM, age, and weather. Differences between groups for BW and nutritional parameters were determined by analysis of variance or paired t-test. Both groups gained BW (224 kg) throughout the study, there were no differences (P < 0.1) due to treatment. Diet CP and DOM were affected by date (P > 0.01) as diet quality declined from spring to fall. Percent diet CP was greater (P > 0.05) in PNS than CON, especially during July and August (6.940.10 vs 6.230.17, respectively). Corresponding values for diet DOM were (59.530.55 vs 59.140.43, respectively; P = 0.09). Observed vs model-predicted weight was different (P > 0.05) for both groups when using CP-based outputs, but not when using metabolizable protein-based outputs (P < 0.1). In summary, PNS heifers selected a diet of greater CP than CON, and tended to select a diet greater in DOM.

published proceedings

  • Journal of Animal Science

author list (cited authors)

  • Tolleson, D. R., Randel, R. D., Perry, G. A., Diaz, J. M., Starns, H. D., Knight, C. W., ... Welsh, T. H

publication date

  • January 1, 2021 11:11 AM