Effects of prepartum plane of nutrition during mid- or late gestation on beef cow BW, BCS, blood hormone concentrations, and preimplantation embryo

beef cattle;prepartum nutrition;preimplantation embryo

Meteer, Wynnton ; Shike ; Daniel W. ; Cardoso ; Felipe

关键词: beef cattle;    prepartum nutrition;    preimplantation embryo;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/72887/Wynnton_Meteer.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

The objectives were to evaluate the potential effect of prepartum plane of nutrition during mid- or late gestation on cow BW, BCS, blood hormone concentrations, and preimplantation embryos. In Exp. 1, multiparous Angus and Angus x Simmental cows (n = 33; BW = 664 ± 78 kg) were fed diets formulated to provide 3 planes of nutrition: 100% NRC energy and protein requirement (REQ), 70% NRC requirement (70%REQ) or 130% NRC requirement (130%REQ) during late gestation (91±4 to 8±4 d prepartum). After treatment period, cows were fed a common diet formulated to meet NRC requirements. Cows fed 130%REQ tended (P = 0.06) to have greater BW at breeding when compared with cows fed REQ, cows fed 70%REQ were intermediate. Cows that were fed 130%REQ during late gestation tended (P = 0.09) to have greater average progesterone concentrations than cows that were fed REQ, cows fed 70%REQ were intermediate. There was a tendency (P = 0.07) for cows fed 70%REQ and REQ to have a greater number of total embryos recovered when compared to cows that were fed 130%REQ diet during late gestation. Nutritional plane during late gestation did not affect (P ≥ 0.53) cow cyclicity, embryo quality, embryo development, or the total number of embryos that were frozen. In Exp. 2, multiparous Angus and Angus x Simmental cows (n = 35; BW = 601 ± 72 kg) were fed the same diets as Exp. 1 but were fed during mid-gestation (195 to 112 ± 4 d prepartum). Cows fed REQ and 130%REQ had greater (P = 0.02) BW at breeding when compared with cows fed 70%REQ. Also, cows fed 130%REQ tended (P = 0.06) to have greater BCS at breeding than cows fed 70%REQ during mid-gestation and cows fed REQ were intermediate. Nutritional plane fed during mid-gestation did not affect (P ≥ 0.23) blood hormone concentrations (progesterone, estradiol, and IGF-1). Cows fed 70%REQ and 130%REQ during mid-gestation had a greater (P = 0.03) count of total embryos recovered when compared with cows fed REQ. Nutritional plane during mid-gestation did not affect (P ≥ 0.27) cow cyclicity, embryo quality, embryo development, or the total number of embryos that were frozen. In conclusion, prepartum plane of nutrition tends to affect cow BW and BCS at breeding. Plane of nutrition effects on embryo production differed depending on the stage of gestation at which treatments were applied.