Investigating the relationship between dairy dam preconception and gestation characteristics and heifer offspring variables from birth to lactation.

Little is known about effects of maternal characteristics around gestation in cows on their female offspring in early and later life. The objective of the current study was to investigate the relationship between cow characteristics during the preconception and gestation period, and the BW, energy metabolism, hormones, immune function, liver enzymes, and milk variables of their female offspring from birth until the first 100 d after their first calving. Holstein-Friesian dairy cows (n = 154) were blocked according to parity, milk yield, and SCC, and randomly assigned to a voluntary waiting period (VWP) of 50, 125, or 200 d. Female offspring (n = 62) from those cows were monitored from birth until the first 100 DIM of the offspring's first lactation. Not all dams were inseminated successfully soon after the planned VWP, resulting in differences between the planned VWP and intended calving interval (CInt) and the actual CInt. Dam-offspring pairs were regrouped according to the dam's actual CInt (CInt_1: 324 - 408 d; CInt_2: 409 - 468 d; CInt_3: 469 - 586 d). For data analysis, the dam variables were divided into 4 stages: 4 wk before conception, and the 3 trimesters of gestation. Similarly, the heifer calf variables were divided into 3 stages: calves from birth to weaning, heifers from weaning to calving, and lactating offspring during first 100 DIM after calving. To analyze the effects of preconception and gestation characteristics in dams on female offspring, each dam variable from 4 wk before conception until calving was included separately in a regression model, with fixed effects for dam's CInt, parity, offspring's age, and their 2-way interactions, with an repeated effect of time with female offspring as the repeated subject. Higher milk lactose in dams during the preconception period and the first 2 trimesters of gestation was related to higher BW in heifers from weaning to calving. Heavier dams during the preconception period and gestation had heifers with higher levels of plasma antikeyhole limpet hemocyanin IgG and IgM from weaning to calving. Higher plasma IGF-І concentration in dams in all stages was related to higher plasma IGF-І and insulin concentrations in heifers from weaning to calving, with increasing effect size over dam's stages. Higher milk yield of dams across all stages was associated with lower milk fat content, lower plasma nonesterified fatty acids, and higher glucose concentrations of lactating offspring during the first 100 DIM of their first lactation. Greater milk lactose and lower milk fat content in dams before conception and in the first 2 trimesters of gestation were related to greater BW in lactating offspring. In conclusion, some associations between dam in different stages and female offspring variables were present for all dam periods, but some disappeared over the course of gestation. Moreover, the greatest percentage of associations (16.56%, 159 out of 960 associations with a P-value <0.05) was present when the lactation periods of dams and their female offspring were compared, that is, when dam and offspring were in a similar life stage, compared with earlier life stages of the offspring during weaning (6.17%, 37 out of 600 associations with a P-value <0.05) and rearing (11.67%, 70 out of 600 associations with a P-value <0.05).