1135 A meta-analysis of the impacts of maternal weight and fetal sex on uterine blood flow and maternal heart rate in beef cows from mid- to late-gestation

2016 ◽  
Vol 94 (suppl_5) ◽  
pp. 545-545
Author(s):  
A. R. Tanner ◽  
M. L. Bauer ◽  
V. C. Kennedy ◽  
B. Mordhorst ◽  
L. E. Camacho ◽  
...  
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Meta Analysis ◽  
Beef Cows ◽  
Late Gestation ◽  
Uterine Blood Flow ◽  
Maternal Weight ◽  
Fetal Sex ◽  
Maternal Heart Rate

249 Effects of Maternal Nutrient Restriction During Late Gestation on Uterine Blood Flow and Placental Size in the Primiparous Bovine Dam

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 129-129
Author(s):  
Colby A Redifer ◽  
Lindsey G Wichman ◽  
Allison M Meyer
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Color Doppler ◽  
Placental Weight ◽  
Late Gestation ◽  
Nutrient Restriction ◽  
Uterine Blood Flow ◽  
Pre Treatment

Abstract To determine effects of late gestational maternal nutrient restriction (NR) on uteroplacental blood flow and placental growth, primiparous fall-calving crossbred beef heifers [BW: 451 ± 28 (SD) kg; BCS: 5.4 ± 0.7] were individually-fed either 100% (control; CON; n = 12) or 70% (n = 13) of energy and protein requirements for maintenance, pregnancy, and growth during the last 120 days of gestation. Transrectal color Doppler ultrasonography of both uterine arteries was conducted pre-treatment and every 21 d during treatments. Placentas were split into ipsilateral and contralateral sides, dissected (cotyledonary vs. intercotyledonary), and dried. Data were analyzed with treatment, treatment initiation date, and calf sex (when P < 0.25) as fixed effects. Uterine blood flow included day and treatment x day (repeated measures). Dam BW was less (P ≤ 0.01) from d 223 of gestation through parturition for NR dams, but calf BW was not affected (P = 0.72) by treatment. The interaction affected (P < 0.01) heart rate, where NR dams had decreased heart rate after treatments began. Treatment did not affect (P ≥ 0.20) uterine artery blood flow or hemodynamics, but all variables were affected (P ≤ 0.04) by day. Contralateral total and cotyledonary weights tended (P ≤ 0.09) to be greater and ipsilateral and total cotyledonary:intercotyledonary ratios were greater (P ≤ 0.01) for CON. Cotyledon number, cotyledon size, and total cotyledonary, intercotyledonary, and placental weight were not affected (P ≥ 0.15) by treatment. Relative to dam BW, uterine blood flow was not affected (P = 0.83), but relative placental weight tended to be greater (P = 0.09) in NR dams. In the current study, NR dams lost maternal BW during late gestation and had less contralateral placental growth, yet uterine blood flow was maintained and placental size relative to BW ensured fetal growth similar to CON offspring.

scholarly journals 298 Effects of parity on late gestational uterine blood flow and hemodynamics in beef cattle

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 137-138
Author(s):  
Allison M Meyer ◽  
Natalie B Duncan ◽  
Katy S Stoecklein ◽  
Emma L Stephenson
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Birth Weight ◽  
Pulsatility Index ◽  
Uterine Artery ◽  
Color Doppler ◽  
Peak Systolic Velocity ◽  
Late Gestation ◽  
Artery Blood Flow ◽  
Diastolic Velocity

Abstract To determine parity effects on late gestational uteroplacental blood flow, uterine artery hemodynamics were measured in 13 primiparous and 11 multiparous (parity 3 and 4) non-lactating, fall-calving crossbred females beginning 109 d prepartum. Females were nutritionally managed as one group to meet or exceed nutrient requirements. Transrectal color Doppler ultrasonography of the both uterine arteries was conducted 3 to 6 times per female across late gestation, ending at approximately 20 d prepartum. Data were analyzed with parity (primiparous vs. multiparous), day prior to calving, and their interaction in the model; day was a repeated effect. Dam BW was greater (P < 0.001) for multiparous than primiparous females, and increased (P = 0.004) as gestation progressed. Calf birth weight was unaffected (P = 0.87) by parity. The parity x day interaction tended to affect (P = 0.06) ipsilateral uterine artery blood flow (L/min), where multiparous cows had a greater increase per day. Total and contralateral uterine artery blood flow were unaffected (P ≥ 0.11) by parity, but increased (P < 0.001) with day of gestation. When expressed relative to dam BW, total and contralateral blood flow were greater (P ≤ 0.04) in primiparous than multiparous females; ipsilateral blood flow was unaffected (P ≥ 0.13) by parity, however. Ipsilateral pulsatility index and both resistance indices were unaffected (P ≥ 0.28) by parity and day, but day tended to affect (P = 0.07) contralateral pulsatility index. Parity did not affect (P ≥ 0.11) cross-sectional area, mean velocity, peak systolic velocity, and end diastolic velocity of either uterine artery, but all increased (P < 0.001) as gestation progressed. Heart rate was greater (P = 0.03) in primiparous than multiparous females. Data suggest that uterine artery blood flow and heart rate may be altered in primiparous females, even when birth weight is unaffected by parity.

487 Effect of melatonin supplementation during mid- to late-gestation on maternal uterine blood flow and calf size at birth

2017 ◽  
Vol 95 (suppl_4) ◽  
pp. 238-238
Author(s):  
K. J. McCarty ◽  
M. P. T. Owen ◽  
C. G. Hart ◽  
K. C. Yankey ◽  
R. C. Thompson ◽  
...  
Keyword(s):  
Blood Flow ◽  
Late Gestation ◽  
Uterine Blood Flow ◽  
Size At Birth

Maternal responses to long-term hypoxemia in sheep

1989 ◽  
Vol 256 (6) ◽  
pp. R1340-R1347 ◽  
Author(s):  
T. Kitanaka ◽  
R. D. Gilbert ◽  
L. D. Longo
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Blood Volume ◽  
Cardiovascular Responses ◽  
Uterine Blood Flow ◽  
O2 Uptake ◽  
Arterial Po2

To determine the maternal cardiovascular responses to long-term hypoxemia, we studied three groups of animals: 1) pregnant ewes (n = 20) at 110-115 days gestation subjected to hypoxia for up to 28 days; 2) pregnant ewes (n = 4) that served as normoxic controls; and 3) nonpregnant ewes (n = 6) subjected to hypoxemia for up to 28 days. We measured mean arterial pressure, heart rate, uterine blood flow, and uterine vascular resistance continuously for 1 h/day while the ewe was exposed to an inspired O2 fraction of 12-13% for at least 17 days. Arterial PO2, O2 saturation, hemoglobin, arteriovenous O2 difference, and uterine O2 uptake were measured daily while blood volume and erythropoietin concentration were measured weekly. In the pregnant hypoxic group arterial PO2 decreased from a control value of 101.5 +/- 5.1 to 59.2 +/- 5.1 Torr within a few minutes, where it remained throughout the study. The hemoglobin concentration increased from 8.9 +/- 0.5 to 10.0 +/- 0.5 g/dl within 24 h where it remained, whereas erythropoietin concentration increased from 16.6 +/- 2.1 to 39.1 +/- 7.8 mU/ml at 24 h but then returned to near-control levels. Arterial glucose concentration, mean arterial pressure, and cardiac output decreased slightly but insignificantly. In contrast, body weight, heart rate, blood volume, uterine blood flow, uterine O2 flow, uteroplacental O2 uptake, and the concentrations of catecholamines and cortisol remained relatively constant. Thus both pregnant and nonpregnant sheep experience relatively minor cardiovascular and hematologic responses in response to long-term hypoxemia of moderate severity.

Uterine blood flow and substrate uptake in conscious rabbit during late gestation

1984 ◽  
Vol 247 (5) ◽  
pp. E574-E580 ◽  
Author(s):  
M. Gilbert ◽  
S. Hauguel ◽  
M. Bouisset
Keyword(s):  
Blood Flow ◽  
Ketone Bodies ◽  
Glucose Consumption ◽  
Late Gestation ◽  
Gravid Uterus ◽  
Glucose Turnover ◽  
Substrate Uptake ◽  
Uterine Blood Flow ◽  
Fourfold Increase ◽  
Fick Principle

The aim of this study was the quantitation of the metabolic demands of the uterus in rabbits between days 24 and 30 of gestation, a time at which there is a fourfold increase in fetal weight. Serial measurements of substrate concentrations in maternal artery and uterine vein were performed over this period. Uterine blood flow was measured on days 24 and 30. Uterine substrate uptake was calculated by application of the Fick principle. Over the gestation range studied, the absolute uterine blood flow increased proportionally to the uterine weight gain. The uterine arteriovenous differences for glucose (G), lactate (L), free fatty acids (FFA), ketone bodies (KB), and oxygen (O2) were constant throughout the study. At both gestational ages, the weight-specific uterine substrate consumption (G, FFA, KB, O2) and production (L) were respectively similar. On days 24 and 30 the amount of G directed to the gravid uterus represented approximately 13 and approximately 36% of the maternal glucose turnover rate, respectively. The maximum contributions of G and FFA to the uterine oxygen consumption on day 24 were 80 and 30%, respectively. We have thus confirmed that at term the gravid uterus is a site of high glucose consumption. Finally, we demonstrated that in a nonruminant species, FFA would be a substantial source of carbon.

scholarly journals Large Conductance Ca2+-Activated and Voltage-Activated K+ Channels Contribute to the Rise and Maintenance of Estrogen-Induced Uterine Vasodilation and Maintenance of Blood Pressure

Endocrinology ◽  
2012 ◽  
Vol 153 (12) ◽  
pp. 6012-6020 ◽  
Author(s):  
Charles R. Rosenfeld ◽  
Timothy Roy
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Uterine Artery ◽  
K Channel ◽  
Uterine Blood Flow ◽  
K Channels ◽  
Channel Inhibition ◽  
Estradiol 17Β ◽  
Cgmp Synthesis

Abstract Uterine blood flow (UBF) increases greater than 4-fold 90 min after systemic estradiol-17β (E2β) in nonpregnant sheep and remains elevated longer than 6–8 h; mean arterial pressure (MAP) is unchanged. Large-conductance Ca+2-activated (BKCa) and voltage-activated (KV) K+ channels contribute to the acute rise in UBF; their role in maintaining UBF and MAP longer than 90 min is unknown. We examined this in five nonpregnant, ovariectomized ewes with uterine artery (UA) flow probes and catheters in a UA for infusion of K+ channel inhibitors and uterine vein to sample venous effluent. Animals received systemic E2β (1.0 μg/kg; control), E2β+UA tetraethylammonium (TEA; 0.4–0.8 mm, n = 4), and E2β+UA 4-aminopyridine (4-AP; 0.01–0.08 mm, n = 4) to block BKCa and KV, respectively, while monitoring MAP, heart rate, and UBF. Uterine cGMP synthesis was measured. Ninety minutes after E2β, UBF rose 4.5-fold, uterine vascular resistance (UVR) fell greater than 5-fold and MAP was unchanged [78 ± 0.8 (sem) vs. 77 ± 1.5 mm Hg] in control studies and before UA inhibition with TEA and 4-AP. Between 90 and 120min, UBF, UVR, and MAP were unchanged after E2β alone. E2β+TEA dose dependently decreased ipsilateral UBF and increased UVR (24 ± 8.9 and 38 ± 16%, respectively, at 0.8 mm; P < 0.03); MAP was unchanged. Contralateral UBF/UVR were unaffected. E2β+4-AP also dose dependently decreased ipsilateral UBF and increased UVR (27 ± 5.3 and 76 ± 18%, respectively, at 0.08 mm; P < 0.001); however, MAP rose 27 ± 6.9% (P ≤ 0.006). E2β increased uterine cGMP synthesis greater than 3.5-fold and was unaffected by local K+ channel inhibition. BKCa and KV contribute to the rise and maintenance of E2β-induced uterine vasodilation, which is partially cGMP dependent. Systemic vascular KV also contributes to maintaining MAP after systemic E2β.

scholarly journals Late gestation supplementation of corn dried distiller’s grains plus solubles to beef cows fed a low-quality forage: III. effects on mammary gland blood flow, colostrum and milk production, and calf body weights

2019 ◽  
Vol 97 (8) ◽  
pp. 3337-3347 ◽  
Author(s):  
Victoria C Kennedy ◽  
James J Gaspers ◽  
Bethany R Mordhorst ◽  
Gerald L Stokka ◽  
Kendall C Swanson ◽  
...  
Keyword(s):  
Blood Flow ◽  
Mammary Gland ◽  
Milk Production ◽  
Beef Cows ◽  
Late Gestation ◽  
Arterial Blood Flow ◽  
Total Blood ◽  
Distiller's Grains ◽  
Arterial Blood ◽  
Term Performance

Abstract Objectives were to investigate the effects of supplementation with corn dried distiller’s grains plus solubles (DDGS) to late gestating beef cows on arterial blood flow to the mammary glands during late gestation and early lactation; colostrum and milk production; dystocia and immunity; and calf BW. Cows were fed a control (CON; n = 15; 5.1% CP; 36.2% ADF) diet consisting of 90% corn stover and 10% corn silage on a dry basis offered ad libitum or CON diet with supplementation of DDGS (0.30% of BW; SUP n = 12). Mammary gland blood flow was assessed on day 245 of gestation. At parturition, maternal and calving parameters were assessed; colostrum and jugular blood was sampled; and dams were weighed. Mammary gland blood flow and milk production was measured on day 44 of lactation. Calves were weighed fortnightly for 8 wk and at weaning. Colostrum production tended to be greater in SUP dams than in CON dams (837 vs. 614 ± 95 g, P = 0.10). Calves of SUP dams were heavier at birth and 24 h (0 h, 43.2 vs. 39.8 ± 1.0 kg, P = 0.02; 24 h, 44.0 vs. 40.4 ± 1.1 kg, P = 0.02). At birth and 24 h, blood pCO2 was greater in calves born to SUP dams (6.82 vs. 6.00 ± 0.41 kPa, P = 0.04). Serum IgG did not differ (P = 0.21) at 24 h. Ipsilateral mammary gland blood flow of SUP cows was greater than CON cows (2.76 vs. 1.76 ± 0.30 L/min; P = 0.03); however, when summed with contralateral, total blood flow was similar (P = 0.33). Hemodynamic measures on day 44 of lactation were similar (P ≥ 0.32). Milk production tended to be increased (13.5 vs. 10.2 ± 1.2 kg/d, P = 0.07) in SUP vs. CON cows. Despite similar BW through 56 d, calves from SUP cows were heavier (P = 0.04) at weaning (309.7 vs. 292.0 ± 6.0 kg). In conclusion, we accept our hypothesis that DDGS supplementation during gestation influenced mammary blood flow, milk production and calf weights. These findings implicate maternal nutrition’s leverage on both nutrient and passive immunity delivery to the calf early in life as well as potential advantages on long-term performance.

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