Energy metabolism of pregnant zebu and crossbred zebu dairy cattle

• DOI: 10.1371/journal.pone.0246208
• Publication Date: 2021-02-04T22:52:55Z
• Authors: Helena Ferreira Lage; Ana Luiza da Cost...; Ricardo Reis e Silva; Alan Maia Borges; José Reinaldo Men...; Pedro Henrique Ar...; Marcelina Pereira...; Paolo Antônio Dut...; Lúcio Carlos Gonç...; André Santos de S...; Antônio Último de...; Elias Jorge Facur...; Edilane Aparecida...; Joana Ribeiro da ...; Alexandre Lima Fe...; Rodrigo Melo Meneses; Eloísa de Oliveir...
• Keywords: Zebu; Beef Cattle

The purpose of this study was to determine the energy partition pregnant F1 Holstein x Gyr with average initial body weight (BW) 515.6 kg and cows BW 435.1 at 180, 210 240 days gestation, obtained using respirometry. Twelve animals in two groups (six per genetic group) received a restricted diet equivalent 1.3 times net for maintenance (NE m ). proportion gross intake (GEI) lost as feces did not differ between evaluated breeds corresponded 28.65% on average. daily methane production (L/d) greater (P<0.05) HxG compared animals. However, when expressed L/kg dry matter (DM) or percentage GEI there were no differences (P>0.05). loss urine (mean 1.42 Mcal/d) (P>0.05) ranged from 3.87 5.35% GEI. metabolizable (MEI) (P < 0.05) all gestational stages Mcal/d. kcal/kg metabolic (BW 0,75 ), had MEI 11% gestation averaged 194.39 . showed change over time (P>0.05), mean 146.66 0. 75 ME used by conceptus calculated deducting (ME ) MEI, which previous same prior becoming pregnant. values NEm similar non-pregnant 92.02 0.75 HxG, 76.83 = 0.06). pregnancy p 5.33 Mcal/d 4.46 Gyr. metabolizability ratio, averaging 0.60, among / Digestible Energy (DE) ratio differed periods 0.84. heat increment (HI) accounted 22.74% 24.38% cows, respectively. basal metabolism represented 29.69%. evaluation NE 2.76