A pilot study to examine the impact of energy restriction in pregnant heifers on female offspring performance, diet digestibility and gastrointestinal tract biometry

Evidence indicates that offspring phenotype may be programmed by maternal conditions in ruminants. We hypothesised that undernutrition from preconception to early gestation in dairy heifers may alter average daily gain (ADG), behavioural patterns, apparent total tract digestibility (ATTD) and gastrointestinal tract (GIT) biometry in single female progeny. Starting 10d pre-insemination, Holstein-Friesian heifers were individually fed at: (i) 0.6 (60%) of their maintenance energy requirements (M; estimated with National Research Council guidelines) to day of gestation (DG) 80 (Restricted, R80; n = 16) or (ii) DG120 (R120, n = 16), or (iii) 1.8 (180%) M to DG120 (Control, CTR; n = 10). Heifers were sired by X-sorted semen from a single bull. Maternal DMI was reduced in R80 and R120 compared to CTR dams (p < 0.05) from −10 to DG80 and DG120, respectively; DMI remained lower in the R80 (9.94 ± 0.09 kg/d) and R120 (10.21 ± 0.07 kg/d) heifers vs CTR (11.16 ± 0.11 kg/d) heifers from DG140 to calving. Insulin peripheral concentrations were lower in R120 than CTR dams on DG90 and 120 (p < 0.05). R80 daughters spent more time feeding at 30 and 74d of age; progeny’s DMI, ADG and digestibility estimates were similar. The duodenum tended to be heavier in CTR vs R calves (p = 0.078), while live and carcase weight, BCS, gastrointestinal organs weight and length were similar among calves at 135d of age. Findings indicate that imbalanced feeding in early gestation in dairy heifers does not influence GIT organ morphometrics in juvenile female progeny.