Stable isotopes of C and N differ in their ability to reconstruct diets of cattle fed C3-C4 forage diets

David M Jaramillo; Jose C B Dubeux Jr; Martin Ruiz-Moreno; Nicolas DiLorenzo; Joao M B Vendramini; Lynn Sollenberger; Cheryl Mackowiak; Luana M D Queiroz; Daciele S Abreu; Liza Garcia; Erick R S Santos; Burney A Kieke Jr

doi:10.1038/s41598-022-21051-4

Stable isotopes of C and N differ in their ability to reconstruct diets of cattle fed C₃-C₄ forage diets

Sci Rep. 2022 Oct 13;12(1):17138. doi: 10.1038/s41598-022-21051-4.

Authors

Affiliations

¹ Agronomy Department, North Florida Research and Education Center, University of Florida, 3925 Highway 71, Marianna, FL, 32446, USA. [email protected].
² Institute for Environmentally Integrated Dairy Management, USDA-ARS U.S. Dairy Forage Research Center, 2615 Yellowstone Dr., Marshfield, WI, 54449, USA. [email protected].
³ Agronomy Department, North Florida Research and Education Center, University of Florida, 3925 Highway 71, Marianna, FL, 32446, USA.
⁴ Department of Animal Sciences, North Florida Research and Education Center, University of Florida, 3925 Highway 71, Marianna, FL, 32446, USA.
⁵ Agronomy Department, Range Cattle Research and Education Center, University of Florida, 3401 Experiment Station, Ona, FL, 33865, USA.
⁶ Agronomy Department, University of Florida, 3111 McCarty Hall B, Gainesville, FL, 32611, USA.
⁷ Soil and Water Sciences Department, North Florida Research and Education Center, University of Florida, 155 Research Rd., Quincy, FL, 32351, USA.
⁸ Faculty of Agricultural, Life, and Environmental Sci-Ag, Food & Nutrition Science Department, University of Alberta, 16 St. and 85 Ave., Edmonton, AB, T6G 2R3, Canada.
⁹ Marshfield Clinic Research Institute, 1000 N. Oak Ave., Marshfield, WI, 54449, USA.

Abstract

Stable isotopes are useful for estimating livestock diet selection. The objective was to compare δ¹³C and δ¹⁵N to estimate diet proportion of C₃-C₄ forages when steers (Bos spp.) were fed quantities of rhizoma peanut (Arachis glabrata; RP; C₃) and bahiagrass (Paspalum notatum; C₄).Treatments were proportions of RP with bahiagrass hay: 100% bahiagrass (0%RP); 25% RP + 75% bahiagrass (25%RP); 50% RP + 50% bahiagrass (50%RP); 75% RP + 25% bahiagrass (75%RP); and 100% RP (100% RP). Feces, plasma, red blood cell (RBC), and hair were collected at 8-days intervals, for 32 days. Two-pool mixing model was utilized to back-calculate the proportion of RP based on the sample and forage δ¹³C or δ¹⁵N. Feces showed changes using δ¹³C by 8 days, and adj. R² between predicted and observed RP proportion was 0.81 by 8 days. Plasma, hair, and RBC required beyond 32-days to reach equilibrium, therefore were not useful predictors of diet composition during the study. Diets were best represented using fecal δ¹³C at both 8-days and 32-days. By 32-days, fecal δ¹⁵N showed promise (R² = 0.71) for predicting diet composition in C₃-C₄ diets. Further studies are warranted to further corroborate fecal δ¹⁵N as a predictor of diet composition in cattle.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animal Feed / analysis
Animals
Cattle
Diet* / veterinary
Feces
Isotopes
Paspalum*

Substances

Isotopes