Effects of early gestational undernutrition on fetal growth, organ development, and placentomal composition in the bovine1

Abstract

Fetal intrauterine growth restriction (IUGR) is known to negatively affect offspring health postnatally. This study evaluated the impacts of early gestational undernutrition followed by realimentation on bovine fetal and placental growth. Thirty multiparous beef cows bred to a single sire and gestating female fetuses were fed to meet NRC recommendations (control; n = 15) or fed below NRC recommendations (68.1% of NE(m) and 86.7% of MP recommendations; nutrient restricted, NR; n = 15) from d 30 to 125 of gestation. On d 125 of gestation, 10 control and 10 NR cows were necropsied. The remaining 5 NR cows were realimented to achieve similar BW and BCS with the remaining 5 control cows by d 190 of gestation; both groups were necropsied at d 245 of gestation. Fetal weight at d 125 of gestation was 948 +/- 14 g (n = 10) for control cows; however, fetal weights of NR cows fell into 2 distinct groups: NR non-IUGR cows had fetal weights similar to control cows (974 +/- 20 g, n = 6), whereas fetal weights of NR IUGR cows were reduced (773 +/- 23 g, n = 4; P < 0.01). Fetal brain weight as a percentage of fetal weight was increased (approximately 11%; P < 0.01) in the NR IUGR fetuses compared with fetuses from the other 2 groups, which were similar. Fetal heart weight as a percentage of fetal weight also tended to be increased (approximately 10%; P = 0.08) in NR IUGR fetuses compared with control fetuses. Nutrient-restricted IUGR cows exhibited reduced (P < 0.01) cotyledonary weights compared with NR non-IUGR and control cows, which were similar (192 +/- 27 vs. 309 +/- 22, and 337 +/- 17 g, respectively). Total placentome surface area also tended to be reduced (P = 0.07) in NR IUGR cows compared with NR non-IUGR and control cows, which again were similar (685.0 +/- 45.6 vs. 828.7 +/- 37.2 and 790.7 +/- 28.9 mm(2), respectively). On d 245 of gestation, fetal weights and caruncle weight were similar for NR and control cows; cotyledonary weights, however, were reduced in NR vs. control cows (1,430 +/- 133 vs. 2,137 +/- 133 g, P < 0.01). Decreased fetal growth in NR IUGR cows on d 125 of gestation was associated with decreased cotyledonary weights and reduced placentomal surface areas. The return of NR cows to a BW and BCS similar to that of control cows through realimentation beginning on d 126 resulted in similar fetal weights of NR and control cows by d 245 of gestation. Thus, a bout of fetal IUGR may go undetected if cows undernourished during early gestation receive feed supplementation in the second half of gestation to assure normal birth weight.

Late gestation supplementation of beef cows differing in body condition score: Effects on cow and calf performance1,2

“…Nevertheless, even though differences in organ cellular composition and function were noted, Long et al (2009Long et al ( , 2010b showed that when beef cows are provided nutrients at a level that meets nutritional requirements during late gestation, it can ameliorate many of the negative consequences (growth and carcass characteristics) of intrauterine growth restriction resulting from early-to midgestational nutrient restriction. Also, other research with late-gestational supplementation of cows has resulted in positive effects on age at puberty and pregnancy rate of female offspring (Martin et al, 2007;Funston et al, 2010).…”

“…Prior research has shown that nutrient restriction during early to mid-gestation negatively affects fetal growth (Wu et al, 2004), including myogenesis and adipogensis (Du et al, , 2011, decreases tenderness and adipose tissue deposition , decreases the responsiveness of the hypothalamic-pituitary-adrenal axis in female progeny (Long et al, 2010a), organ development and function (Long et al, 2009), and gene expression (Long et al, 2010b). Nevertheless, even though differences in organ cellular composition and function were noted, Long et al (2009Long et al ( , 2010b showed that when beef cows are provided nutrients at a level that meets nutritional requirements during late gestation, it can ameliorate many of the negative consequences (growth and carcass characteristics) of intrauterine growth restriction resulting from early-to midgestational nutrient restriction.…”

“…A growing body of evidence suggests that gestational nutrition can alter offspring body composition and growth, hormonal balance, cardiovascular development, metabolic function, neonatal health, organ development and function (Wu et al, 2006;Long et al, 2009), and gene expression (Long et al, 2010b). However, Long et al (2009Long et al ( , 2010b indicated that providing beef cows sufficient nutrition during late gestation can ameliorate many of the negative consequences of intrauterine growth restriction that occur in early to mid-gestation, specifically related to organ growth, animal performance, and carcass characteristics, even though some differences in organ cellular composition and function were not corrected by realimentation. Nevertheless, Stalker et al (2006) provided supplemental protein to mature cows during the last 90 d of gestation and improved calf survivability, weaning performance, and economic returns.…”

Dysregulation of methylation and expression of imprinted genes in oocytes and reproductive tissues in mice of advanced maternal age

“…Decreased nutrient supply has been associated with fetal growth restriction and smaller placental weights in guinea-pigs [48,49], sheep [50], rats [51], and cattle [52]. Growth restricted placentas in the mouse are capable of maintaining normal fetal growth until late in gestation, in part by increasing the expression of glucose (Slc2a3/GLUT3) and System A amino acid (Slc38a4/SNAT4) transporters [53].…”

Establishment of fetal age equations based on ultrasound measurements in cross-bred Holstein cows

“…However, genetic make-up of the conceptus and its interactions with environmental factors play an important role on fetal development and gestation in the cows. Not only the sire's and dam's contribution to difference in genes but certain limited factors including number of fetuses, sex, parity or age of cattle, heat or cold stress, nutrition [24][25][26] possibly affect on potential for growth and on inaccuracy of fetal age estimation of crossObjective: To establish fetal age equations based on ultrasound measurements in cross-bred Holstein cows in Thailand. Methods: The animals were bred for 30-120 d before pregnancy diagnosis using transrectal ultrasonography with real-time B-mode and specify 5 or 7.5 MHz linear array transducer.…”