374 Effects of maternal nutrition on secretion of leptin in the neonatal heifer and interaction of maternal and postnatal nutrition on age at puberty and postpubertal secretion of luteinizing hormone

Abstract

Nutrition during gestation and early postnatally can program developmental changes in the offspring that persist until adult life. Here we tested the hypotheses that maternal nutritional during the second and third trimesters of gestation 1) affects neonatal secretion of leptin in heifer offspring, and 2) interacts with dietary energy intake during the juvenile period to affect age at puberty and postpubertal pulsatile secretion of luteinizing hormone (LH) in heifers. Bos indicus-influenced beef cows (n = 108) in 3 replicates bearing heifer fetuses were assigned randomly to receive low (L), moderate (M), or high energy (H) diets to achieve body condition scores (BCS) of 3–3.5 (thin; n = 36), 5.5–6 (moderate; n = 36), or 7.5–8 (obese; n = 36) by the second trimester of gestation until calving. Heifer offspring were weaned at 3–3.5 months of age and assigned randomly to either a high- (H; 1 kg/day) or low-gain (L; 0.5 kg/day) diet for 5 months. Blood samples from a subgroup of 30 heifers (Exp. 1) from cows in each maternal treatment (n = 10/treatment) were collected once every 2–3 days for 2 weeks after birth. In Exp. 2, 18 heifers representing 3 of the maternal × postnatal groups (HH, MH and LL) were ovariectomized and received estradiol replacement (OVX+E) after puberty. Pulsatile secretion of LH was evaluated for 5.5 hours. Maternal nutrition did not affect postnatal circulating leptin. Based on two replicates (n = 61), postnatal diets had the greatest effect on age at puberty (L > H; P < 0.001), with a lesser maternal diet effect (P < 0.10), although LL > HH by 99 days. None of the characteristics of pulsatile LH secretion differed among treatments in OVX + E heifers. Dietary effects on age at puberty were not associated with hormonal characteristics evaluated in these initial studies.

Effects of Maternal Nutrition on Female Offspring Weight Gain and Sexual Development

“…Previous studies have indicated that maternal nutrition during pregnancy can interact with nutrition in early postnatal life to determine the puberty age in heifers ( Cardoso et al, 2020 ). Furthermore, although postnatal nutrition has more significant effects than maternal nutrition, heifers from mothers that underwent nutritional restriction were more sensitive to the negative effects of limited postnatal growth ( O’Neil et al, 2019 ). Therefore, it is justifiable that the heifers used in our study do not show differences of puberty ages when they start receiving the same environmental conditions, regardless of maternal treatment groups, and did not undergo nutritional restrictions that could limit their postnatal growth in their first months of life, since the animals were born in the rainy season.…”

Improving Beef Progeny Performance Through Developmental Programming

“…Specifically, research has demonstrated heifers born to energy restricted dams had a reduction in antral follicles compared to control cohorts (Sullivan et al, 2009;Mossa et al, 2013). Suboptimal maternal nutrient status also results in disruptions within the neuroendocrine system of the female offspring, leading to altered reproductive function (O'Neil et al, 2019). However, other studies have reported contrasting outcomes to heifer progeny due to long-term exposure to nutrient restriction during gestation (Roberts et al, 2009;Beard et al, 2019).…”

Supplementing Trace Minerals to Beef Cows during Gestation to Enhance Productive and Health Responses of the Offspring

“…Heifers born to energy-restricted dams had a reduction in antral follicle count compared to heifers born to control-fed cohorts [ 9 , 20 , 21 ], a trait that is positively correlated with pregnancy success in both beef heifers and dairy cows [ 22 , 23 , 24 ]. Suboptimal maternal nutrient status during gestation also results in alterations within the neuroendocrine system of the female offspring, leading to delayed puberty attainment and disrupted reproductive function [ 25 ]. Taken together, these findings indicate maternal nutritional status during gestation significantly impacts offspring growth and development [ 3 ], leading to long-term effects on performance and quality of carcass traits [ 3 , 26 ] and altered reproductive function of female progeny [ 27 ].…”