23 Performance of Pregnant Beef Heifers During Spring Rotational Grazing of Novel Endophyte Tall Fescue Following Complete Renovation.

Autor: Talbott, Charlotte L, Harmon, Deidre D, Poore, Matt H, Young, Carolyn, Franzluebbers, Alan J, Griffith, Emily H, Bustabad, Reagan, Newsome, Madeline
Předmět:
Zdroj: Journal of Animal Science; 2022 Supplement, Vol. 100, p15-15, 1p
Abstrakt: The objective of this study was to analyze animal performance following renovation of toxic-infected tall fescue (TF) to novel endophyte tall fescue (NE) in order to increase producer adoption of NE. In 2018, three renovation strategies were implemented in a randomized complete block design. Strategies included: 1) control (C), 2) renovation to NE after one season of a single-specie cover crop (1-SM), 3) renovation to NE after three seasons of a single-specie cover crop (3-SM), and 4) renovation to NE after three seasons of a multi-specie cover crop (3-CM). Forty-eight pregnant (30-90-d) Angus heifers (initial BW 383 kg ± 32) were randomly assigned to rotationally graze spring growth for 56-d, two years after NE establishment. Pre- and post-grazing forage mass was measured every 7-d. Animal measurements were collected every 14-d. Data were analyzed using procGLIMMIX of SASv9.4. Average daily gain was greatest (P < 0.0001) for cattle grazing 3-CM (0.74 kg/d), 1-SM (0.72 kg/d), and 3-SM (0.62 kg/d) and least for C (0.33 kg/d). Pre-grazing forage biomass was greatest (P = 0.0157) in 3-CM (3261 kg/ha) and lowest in C (2523 kg/ha), with 3-SM (2813 kg/ha) and 1-SM (2779 kg/ha) being intermediate. Post-grazing forage biomass was greatest (P = 0.0063) in 3-CM (1982 kg/ha), C (1916 kg/ha), 1-SM (1900 kg/ha), but lower in 3-SM (1592 kg/ha). Prior to grazing, body condition score (BCS) was higher (P = 0.0029) for animals grazing C (5.48), but change in BCS of animals within treatments was not different (P = 0.798). Hair shedding scores (HS) were not different on d-0, with all treatments near 5. However, HS were highest (P < 0.0001) in C (4.75), and lowest in 1-SM (1.75), 3-SM (2), and 3-CM (2) after 56-d. Data suggest animal performance for NE was improved compared to TF during spring grazing in years following renovation. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index