scholarly journals 107 Influence of chronic melatonin supplementation on bovine testis physiology

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 42-42
Author(s):  
Brittni P Littlejohn ◽  
Kayla B Mercer ◽  
Karrigan J Bowers ◽  
Riley D Messman ◽  
Zully Contreras-Correa ◽  
...  

Abstract The objective was to evaluate the influence of melatonin supplementation on bovine testis biometrics, thermoregulation, and blood flow in two age groups. Mature and peri-pubertal bulls received four subdermal 24 mg melatonin implants (MEL; n = 5 and n = 6, respectively) or no implants (CON; n = 5 and n = 6, respectively) every 30 ± 4 d for 120 ± 5 d. Body weight, scrotal circumference (SC), testes temperature (average temperature of left and right testes as quantified with thermal imaging), and total testicular artery blood flow (TBF; total blood flow to left and right testes as measured with Doppler ultrasonography) were evaluated on d 60, 90, and 120 ± 4. On d 120, peri-pubertal bulls were castrated and total testes weight (TTW) determined. Data were analyzed using MIXED procedures of SAS specific for repeated measures with treatment, time, and the interaction as fixed effects and sire (peri-pubertal only) as a random effect. On d 120, peri-pubertal bull data were analyzed using MIXED procedures of SAS with treatment as a fixed effect and sire as a random effect, and relationships of TBF, SC, TTW, testes temperature, and ambient temperature assessed using CORR procedures of SAS. Body weight, testes temperature, TBF, and TBF as a proportion of SC changed over time in peri-pubertal (P < 0.05) but not mature (P > 0.05) bulls. On d 120, TBF was increased (P = 0.05) and TBF as a proportion of TTW tended (P = 0.10) to be increased in MEL (95.48 ± 14.63 mL/min and 0.29 ± 0.03 mL/min*g, respectively) compared to CON (65.06 ± 15.10 mL/min and 0.21 ± 0.03 mL/min*g, respectively) peri-pubertal bulls. TBF was positively correlated with SC (r = 0.59; P = 0.04) and TTW (r = 0.66; P = 0.02). Ambient temperature was positively correlated with testes temperature (r = 0.78; P < 0.01). No other differences were identified (P > 0.05). Limited alterations in testis physiology were observed in melatonin-supplemented bulls.

Author(s):  
Miriam S Martin ◽  
Michael D Kleinhenz ◽  
Abbie V Viscardi ◽  
Andrew K Curtis ◽  
Blaine T Johnson ◽  
...  

Abstract Castration is a routine procedure performed on beef and dairy operations in the U.S. All methods of castration cause behavioral, physiologic, and neuroendocrine changes associated with pain. The American Veterinary Medical Association and the American Association of Bovine Practitioners recommend that anesthesia and analgesia be administered at castration. The objective of this study was to evaluate the effectiveness of bupivacaine liposome suspension a novel, long-acting, local anesthetic administered as a nerve block at castration. The authors chose to investigate this novel formulation as an alternative to current industry standards using lidocaine nerve blocks alone, or in combination with meloxicam. Thirty male Holstein calves, 16-20 weeks of age, were enrolled and randomly assigned to 1 of 4 treatment groups prior to surgical castration: 1) bupivacaine liposome suspension block + oral placebo (BUP); 2) lidocaine block + oral placebo (LID); 3) lidocaine block + oral meloxicam (1 mg/kg) (LID + MEL); and 4) saline block + oral placebo (CON). Biomarkers were collected at -24 h and from 0 to 120 hours post-castration and included infrared thermography, pressure mat gait analysis, chute defense and behavior scoring (pain and activity), and blood sampling for serum cortisol and prostaglandin E2 metabolites (PGEM). Responses were analyzed using repeated measures, with calf nested in treatment as a random effect, and treatment, time, and their interaction designated as fixed effects. Results from pressure mat gait analysis show the CON had a shorter front limb stance time from baseline (-8.73%; 95% CI: -24.84 to 7.37%) compared to BUP and LID + MEL (> 5.70%; 95% CI: -22.91 to 23.79%) (P < 0.03). The CON tended to have an increase in front limb force from baseline (6.31%; 95% CI: -1.79 to 14.41%) compared to BUP, LID, and LID + MEL (< -5.06%; 95% CI: -14.22 to 0.95%) (P < 0.04). The CON displayed higher counts of hunched standing (2.00; 95% CI: 1.68 to 2.32) compared to LID + MEL (1.43; 95% CI: 1.13 to 1.72) (P = 0.05). The CON had higher cortisol concentrations at 24 h (7.70 ng/mL; 95% CI: 1.52 to 13.87 ng/mL) relative to BUP (3.11 ng/mL; 95% CI: -2.56 to 8.79 ng/mL) (P = 0.002). At 4 and 24 h, LID + MEL had lower PGEM concentrations from baseline (-32.42% and -47.84%; 95% CI: -78.45 to -1.80%) compared with CON (27.86% and 47.63%; 95% CI: 7.49 to 82.98%) (P < 0.02). Administration of bupivacaine liposome suspension as a local anesthetic block at the time of castration was as effective at controlling pain as a multi-modal approach of lidocaine and meloxicam.


Author(s):  
Esteban M Galarza ◽  
Raul M Lizzarraga ◽  
Guillermo A Mattioli ◽  
Anthony J Parker ◽  
Alejandro E Relling

Abstract Weaning and transport represent a high stress time for calves. Preconditioning (PC) by weaning before the transport separate these stressors. The stressors generate oxidative stress, which can be reduced by mineral and vitamin supplementation (MVS) with an antioxidant capacity. Our objective was to evaluate the effect of PC and MVS on performance of steers. The experiment used a 2 × 2 factorial arrangement design, considering a 26-d PC treatment from weaning to transport to the feedlot (d 0); and injectable MVS on d -45, -26, and 0. The MVS consisted of Cu, Zn, Mn, Se, vitamin E (0.2, 0.8, 0.2, 0.1, and 1 mg/kg body weight (BW), respectively), and vitamin A (1190 IU/kg). Sixty Angus-crossbred steers (186.4 ± 27.6 kg) were randomly assigned to the four treatments (MVS+PC; N+PC; MVS+N; N+N; n = 15/treatment). Body weight (BW) was recorded on d -45, -26, 0, 8, 15, and 29. On d 0, an additional BW was taken 30 minutes after the 5-hour transportation (d 0.5). Between d 0 to 29, dry matter intake (DMI) and average daily gain (ADG) to DMI ratio (G:F) were measured. Between d -26 to 29 plasma concentrations of glucose, free fatty acids (NEFA), cortisol, insulin, total antioxidant status (TAS), and thiobarbituric acid-reactive substances (TBARS) were evaluated. Data were analyzed using the MIXED procedure of SAS with repeated measures, using treatment, time, and treatment × time as fixed effects, and steer as a random effect. Between d -26 to 0, there was an interaction of MVS × PC (P ˂ 0.01) for ADG. From d -26 to 0, N+N and N+PC had the greatest and lesser ADG, respectively. On d 0.5, no-PC steers tended to lose BW while the PC steers tended to gain BW (P = 0.09). In the period d 0 to 8, there were no differences (P ≥ 0.27) in DMI, but the PC steers had greater G:F and ADG (P < 0.01) compared with no-PC steers. Plasma NEFA concentration on d 0 was affected by MVS×PC (P < 0.01), because MVS decreased plasma NEFA concentration in no-PC steers, but it increased in the PC steers. Plasma concentrations of glucose, insulin, and cortisol did not differ among treatments (P ≥ 0.23). There was a MVS×PC interaction (P = 0.09) for TAS on d 0; N+N had the greatest and MVS+N had the lowest TAS concentrations. In conclusion, a 26-d PC decreased steers BW compared with no-PC steers. The BW loss during preconditioning was not recovered 29-d after feedlot entry. Despite this BW loss, MVS treatment decreased BW loss in the steers allocated to PC treatment on the day of transport.


2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 221-222
Author(s):  
Melanie D Trenhaile-Grannemann ◽  
Ronald M Lewis ◽  
Stephen D Kachman ◽  
Kenneth J Stalder ◽  
Benny E Mote

Abstract Conformation-based sow selection is performed prior to reaching mature size, yet little is known about how conformation changes as growth continues. To assess conformation changes, 9 conformational traits were objectively measured at 12 discrete time points between 112 d of age and parity 3 weaning on 622 sows in 5 cohorts. The 9 traits included 5 body size traits (body length, body depth at the shoulder and flank, and height at the shoulder and flank) and 4 joint angles (knee, hock, and front and rear pastern). Data were analyzed with a repeated measures model (SAS V 9.4) including cohort and time point as fixed effects, sire as a random effect, and heterogeneous compound symmetry as the covariance structure. Sire variance ranged from 0.16 (body depth shoulder) to 2.00 (body length) cm2 for body size traits and 2.28 (rear pastern) to 4.22 (front pastern) degrees2 for joint angles. Cohort had an effect on all traits (P < 0.05). All traits displayed changes over time (P < 0.001). Size traits increased between 112 d of age and parity 3 weaning (64.16 vs. 107.57 cm, 26.62 vs. 44.14 cm, 23.32 vs. 36.92 cm, 46.10 vs. 73.55 cm, 49.36 vs. 77.47 cm for body length, body depth shoulder and flank, and height shoulder and flank, respectively); however, they fluctuated within parity by increasing during gestation and decreasing at weaning. Knee angle decreased (164.12 vs. 150.72 degrees) while fluctuating within parity by decreasing in the second half of gestation and increasing after weaning. Front and rear pastern angles decreased over time (60.89 vs. 53.74 degrees and 64.64 vs. 55.50 degrees for front and rear pastern, respectively), while biologically negligible change was observed in hock angle (148.63 vs. 147.48 degrees). Sow conformation changes throughout life, and these changes may require consideration when making selection decisions.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 166-167
Author(s):  
Andrea M Osorio ◽  
Kaue T Tonelli Nardi ◽  
Igor Gomes Fávero ◽  
Kaliu G Scaranto Silva ◽  
Kymberly D Coello ◽  
...  

Abstract The effects of a nutritional packet were evaluated on CH4 emissions and apparent total tract nutrient digestibility of feedlot beef steers. Thirty Angus-crossbred steers (BW = 542 ± 8.4 kg) were used in a randomized complete block design and allocated into pens equipped with SmartFeed (C-Lock; 15 steers/treatment). Steers were consuming a steam-flaked corn-based diet (88% concentrate DM basis) ad libitum for the last 65 d on feed, and received the following treatments: 1) control and 2) a nutritional packet [0.29% DM basis; live yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g); Vitamin C (5.4 g/kg); Vitamin B1 (13.33 g/kg); NaCl (80 g/kg); KCl (80 g/kg)]. Methane emissions and apparent total tract nutrient digestibility were measured during 3 periods with 5-d of collections each. Gas emissions from steers were measured utilizing the SF6 tracer technique. Feed and fecal samples were collected once and twice (0700 h and 1600 h) daily, respectively, to determine digestibility of nutrients using iNDF as an internal marker. Steer was considered the experimental unit. Data were analyzed as repeated measures using the MIXED procedure of SAS with the fixed effects of treatment, period, and their interaction, and the random effect of block. No treatment × period interactions (P ≥ 0.125) were observed for DMI and any of the CH4 production variables (g/day, g/kg BW0.75, g/nutrient intake, and g/nutrient digested). Moreover, treatments did not affect digestibility of DM, OM, or ADF (P ≥ 0.300); however, digestibility of NDF was increased for treated cattle (P = 0.013), which resulted in a tendency (P = 0.098) to decrease CH4 production in g per kg NDF intake and decreased (P = 0.020) grams CH4 per kg NDF digested. The nutritional packet may be altering ruminal fermentation on intensively managed steers and improving fiber digestibility, which can have benefits on CH4 emission intensity.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 80-80
Author(s):  
Keira M Cruickshank ◽  
Bayissa Hatew ◽  
Amanda M Gehman ◽  
Karen M Koenig ◽  
Eduardo S Ribeiro ◽  
...  

Abstract The objective of this experiment was to determine how source of selenium (Se) affects dairy cow performance, antioxidant status, and apparent absorption and retention. Multiparous Holstein cows (n = 24; 597 ± 49 kg BW) were blocked by days in milk (161 ± 18) and randomly assigned to receive 0.3 mg/kg of either: 1) organic Se (selenized yeast; ORG; Sel-Plex-Alltech); or, 2) inorganic Se (sodium selenite; INO) premix, top dressed and mixed into a ration daily. After an 11-week adaptation period (blood and milk sampled monthly), cows received an intraruminal dose of Se77 (either Se77 yeast or NaSe77O3) followed by a 4-day period of blood and rumen fluid sampling, and total collection of feces, urine, and milk. Data were analyzed using PROC GLIMMIX in SAS with fixed effects of treatment, time, and their interaction, and random effect of block. Daily DMI (23 ± 0.6 kg), milk yield (35 ± 1.2 kg), plasma glutathione peroxidase (64 ± 4.2 U), and serum Se (0.11 ± 0.003 µg/g) were not different between treatments during the adaptation period. Serum Se77 maximum concentration and area under the curve (AUC) were not different between treatments for 72 hours following infusion, but rumen fluid Se77 AUC was higher (P = 0.02) for ORG cows. Apparent absorption (64 ± 1.3%) and retention (44 ± 1.5%) of the Se77 dose did not differ between treatments. The ORG cows had lower urinary excretion (13 vs. 17 ± 0.6%; P < 0.01), higher milk excretion (6 vs. 2 ± 0.3%; P < 0.01), and similar fecal excretion (36 ± 1.3%; P = 0.9) of Se77 compared to INO cows. These results indicate that ORG Se increased Se content of milk and decreased Se excretion in urine, but did not alter performance, antioxidant status, and apparent absorption and retention of Se in mid-lactation cows.


2020 ◽  
Vol 39 (1) ◽  
Author(s):  
D. Ohlendorf ◽  
K. Kerth ◽  
W. Osiander ◽  
F. Holzgreve ◽  
L. Fraeulin ◽  
...  

Abstract Background The aim of this study was to collect standard reference values of the weight and the maximum pressure distribution in healthy adults aged 18–65 years and to investigate the influence of constitutional parameters on it. Methods A total of 416 healthy subjects (208 male / 208 female) aged between 18 and 65 years (Ø 38.3 ± 14.1 years) participated in this study, conducted 2015–2019 in Heidelberg. The age-specific evaluation is based on 4 age groups (G1, 18–30 years; G2, 31–40 years; G3, 41–50 years; G4, 51–65 years). A pressure measuring plate FDM-S (Zebris/Isny/Germany) was used to collect body weight distribution and maximum pressure distribution of the right and left foot and left and right forefoot/rearfoot, respectively. Results Body weight distribution of the left (50.07%) and right (50.12%) foot was balanced. There was higher load on the rearfoot (left 54.14%; right 55.09%) than on the forefoot (left 45.49%; right 44.26%). The pressure in the rearfoot was higher than in the forefoot (rearfoot left 9.60 N/cm2, rearfoot right 9.51 N/cm2/forefoot left 8.23 N/cm2, forefoot right 8.59 N/cm2). With increasing age, the load in the left foot shifted from the rearfoot to the forefoot as well as the maximum pressure (p ≤ 0.02 and 0.03; poor effect size). With increasing BMI, the body weight shifted to the left and right rearfoot (p ≤ 0.001, poor effect size). As BMI increased, so did the maximum pressure in all areas (p ≤ 0.001 and 0.03, weak to moderate effect size). There were significant differences in weight and maximum pressure distribution in the forefoot and rearfoot in the different age groups, especially between younger (18–40 years) and older (41–65 years) subjects. Discussion Healthy individuals aged from 18 to 65 years were found to have a balanced weight distribution in an aspect ratio, with a 20% greater load of the rearfoot. Age and BMI were found to be influencing factors of the weight and maximum pressure distribution, especially between younger and elder subjects. The collected standard reference values allow comparisons with other studies and can serve as a guideline in clinical practice and scientific studies.


2017 ◽  
Vol 22 (5) ◽  
pp. 414-433 ◽  
Author(s):  
Abdulmaged M. Traish ◽  
Ahmad Haider ◽  
Karim Sultan Haider ◽  
Gheorghe Doros ◽  
Farid Saad

Objectives: In the absence of large, prospective, placebo-controlled studies of longer duration, substantial evidence regarding the safety and risk of testosterone (T) therapy (TTh) with regard to cardiovascular (CV) outcomes can only be gleaned from observational studies. To date, there are limited studies comparing the effects of long-term TTh in men with hypogonadism who were treated or remained untreated with T, for obvious reasons. We have established a registry to assess the long-term effectiveness and safety of T in men in a urological setting. Here, we sought to compare the effects of T on a host of parameters considered to contribute to CV risk in treated and untreated men with hypogonadism (control group). Patients and Methods: Observational, prospective, cumulative registry study in 656 men (age: 60.7 ± 7.2 years) with total T levels ≤12.1 nmol/L and symptoms of hypogonadism. In the treatment group, men (n = 360) received parenteral T undecanoate (TU) 1000 mg/12 weeks following an initial 6-week interval for up to 10 years. Men (n = 296) who had opted against TTh served as controls. Median follow-up in both groups was 7 years. Measurements were taken at least twice a year, and 8-year data were analyzed. Mean changes over time between the 2 groups were compared by means of a mixed-effects model for repeated measures, with a random effect for intercept and fixed effects for time, group, and their interaction. To account for baseline differences between the 2 groups, changes were adjusted for age, weight, waist circumference, fasting glucose, blood pressure, and lipids. Results: There were 2 deaths in the T-treated group, none was related to CV events. There were 21 deaths in the untreated (control) group, 19 of which were related to CV events. The incidence of death in 10 patient-years was 0.1145 in the control group (95% confidence interval [CI]: 0.0746-0.1756; P < .000) and 0.0092 in the T-treated group (95% CI: 0.0023-0.0368; P < .000); the estimated difference between groups was 0.0804 (95% CI: 0.0189-0.3431; P < .001). The estimated reduction in mortality for the T-group was between 66% and 92%. There were also 30 nonfatal strokes and 26 nonfatal myocardial infarctions in the control group and none in the T-treated group. Conclusion: Long-term TU was well tolerated with excellent adherence suggesting a high level of patient satisfaction. Mortality related to CV disease was significantly reduced in the T-group.


2018 ◽  
Vol 3 (1) ◽  
pp. 135-148 ◽  
Author(s):  
Alyssa B Word ◽  
P Rand Broadway ◽  
Nicole C Burdick Sanchez ◽  
Shelby L Roberts ◽  
John T Richeson ◽  
...  

Abstract Two treatments were evaluated in heifers to determine the effects of a yeast supplement on immune and metabolic responses to a combined (tandem viral-bacterial) respiratory disease challenge. Thirty-two beef heifers (325 ± 20.1 kg BW) were selected from a larger population previously assigned to one of two treatments: Control (CON), receiving no yeast supplement in the diet, or yeast (YST), CON diet plus a combination live yeast (2.5 g·heifer−1·d−1) and yeast cell wall (2.5 g·heifer−1·d−1) supplement (Phileo Lesaffre Animal Care, Milwaukee, WI). Heifers were maintained on treatments for 31 d prior to the challenge. On day −3 all heifers were fitted with an indwelling vaginal temperature recording device, received an intranasal challenge with 2 × 108 plaque-forming units of bovine herpesvirus-1 (BHV-1), and placed in outdoor pens. On day 0, all heifers were fitted with an indwelling jugular catheter, challenged intratracheally with an average dose of 3.0 × 107 colony-forming units (cfu) of Mannheimia haemolytica in 100 mL media, and were transferred into individual stanchions in an enclosed, environmentally controlled barn. Whole blood samples were collected at −72 h and at 0, 2, 4, 6, 8, 12, 24, 36, 48, 60, and 72 h (hematology) and at 0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, 36, 48, 60, and 72 h (serum isolation) relative to M. haemolytica challenge (0 h). Data were analyzed using the MIXED procedure of SAS specific for repeated measures with fixed effects of treatment, time, and the treatment × time interaction. Vaginal temperature and cortisol concentrations were similar between treatments (P ≥ 0.39). Although total leukocyte count following BHV-1 challenge was similar between treatments (P = 0.21), there was a tendency (P = 0.07) for CON heifers to have greater neutrophil counts than YST heifers. Serum haptoglobin concentration was similar between treatments (P = 0.13). Heifers in the YST treatment had similar serum glucose concentrations (P = 0.25) and decreased serum concentrations of urea nitrogen compared to CON (P = 0.03). Dietary treatment did not affect serum nonesterified fatty acid concentrations (P = 0.37). Nasal lesion score severity (0–4) tended (P = 0.07) to be decreased in YST compared to CON (2.5 vs. 3.19 ± 0.26), while water intake tended to be increased in YST (P = 0.06). Feeding a yeast supplement had little effect on the acute-phase response but improved metabolic outcomes in heifers during a respiratory disease challenge.


2020 ◽  
Vol 32 (2) ◽  
pp. 227
Author(s):  
C. M. Checura ◽  
S. L. Pratt ◽  
L. V. Campbell ◽  
K. Farmer ◽  
G. Loughlin ◽  
...  

Phototherapy uses monochromatic light from low-power lasers and light-emitting diodes (LEDs) to modulate biological processes. It has been proposed that the red-to-near infrared optical region (~600-1000nm) enhances cellular metabolic activity by activation of the mitochondrial respiratory chain. However, photostimulation induces the generation of oxide free radicals and could create oxidative stress in exposed cells. The main objective was to use photostimulation to affect the cumulus-oocyte complex metabolic state, aiming to enhance cytoplasmic maturation rates and subsequent embryonic development. A secondary objective was to determine the toxicity of the proposed photostimulation protocol. Abattoir-derived ovaries were used. All media was from IVF Biosciences (Falmouth, Cornwall, UK). Follicles 2 to 6mm in diameter were aspirated. Oocytes with compact cumulus and homogeneous cytoplasm were selected, and 50 oocytes/well were placed in invitro maturation medium (0h) and incubated at 38.5°C in 5% CO2 in air with high humidity in the presence (treatment=exposure for 2min to super-bright LED 1 and 2h after the beginning of maturation; LED wavelength of 660-665 nm; NTE30041; NTE Electronics Inc.) or absence (Control) of light. After maturation (22h), oocytes were split into two wells (25 oocytes/well) and subjected to IVF with semen from two different bulls for 18 to 20h. Cumulus cells were separated by vortexing, zygotes were placed in invitro culture medium, and incubated at 38.5°C in 5% CO2 in air with high humidity. Culture medium was renewed every 48h. Cleavage, morula, and blastocyst rates were recorded as a percentage of the number of oocytes subjected to IVF per treatment. The experiment was replicated 4 times. Statistical analysis was conducted using the Mixed procedure (SAS 9.4, SAS Institute Inc.) with repeated-measures and autoregressive covariance. The model's random effect was well within treatment. Fixed effects were bull, stage of development, and treatment. There was no difference (P=0.8) between treatments for any stage of development measured (cleavage: 76.4±2.7 vs. 74.8±4.1; morula: 36.1±4.8 vs. 35.9±5.8; blastocyst: 20.8±3.2 vs. 20.6±4.4 for control and treatment respectively; mean±s.e.). Sire affected development: bull 1 had a greater percentage (P&lt;0.05) cleavage (82.9±0.02 vs. 68.3±0.02), morula (42.6±0.05 vs. 29.4±0.04), and blastocyst (27.8±0.04 vs. 13.6±0.01) development than bull 2. There was no treatment×bull interaction (P=0.9). In conclusion, there were no stimulatory or toxic effects of this preliminary photostimulation protocol. Further research is needed to develop an optimal protocol that shows a metabolic effect and, potentially, an enhancement of invitro cytoplasmic maturation rates and subsequent embryonic development.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 129-129
Author(s):  
Colby A Redifer ◽  
Lindsey G Wichman ◽  
Allison M Meyer

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 &lt; 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 &lt; 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.


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