The ovarian function and endocrine phenotypes of lactating dairy cows during the estrous cycle were associated with genomic-enhanced predictions of fertility potential.

The objectives of this prospective cohort study were to characterize associations among genomic merit for fertility with ovarian and endocrine function and the estrous behavior of dairy cows during an entire, non-hormonally manipulated estrous cycle. Lactating Holstein cows entering their first (n = 82) or second (n = 37) lactation had ear-notch tissue samples collected for genotyping using a commercial genomic test. Based on genomic predicted transmitting ability values for daughter pregnancy rate (gDPR) cows were classified into a high (Hi-Fert; gDPR > 0.6 n = 36), medium (Med-Fert; gDPR -1.3 to 0.6 n = 45), and low fertility (Lo-Fert; gDPR < -1.3 n = 38) group. At 33 to 39 DIM, cohorts of cows were enrolled in the Presynch-Ovsynch protocol for synchronization of ovulation and initiation of a new estrous cycle. Thereafter, the ovarian function and endocrine dynamics were monitored daily until the next ovulation by transrectal ultrasonography and concentrations of progesterone (P4), estradiol, and FSH. Estrous behavior was monitored with an ear-attached automated estrus detection system that recorded physical activity and rumination time. Overall, we observed an association between fertility group and the ovarian and hormonal phenotype of dairy cows during the estrous cycle. Cows in the Hi-Fert group had greater circulating concentrations of P4 than cows in the Lo-Fert group from d 4 to 13 after induction of ovulation and from day -3 to -1 before the onset of luteolysis. The frequency of atypical estrous cycles was 3-fold greater for cows in the Lo-Fert than the Hi-Fert group. We also observed other modest associations between genomic merit for fertility with the follicular dynamics and estrous behavior. There were several associations between milk yield and parity with ovarian, endocrine, and estrous behavior phenotypes as cows with greater milk yield and in the second lactation were more likely to have unfavorable phenotypes. These results demonstrate that differences in reproductive performance between cows of different genomic merit for fertility classified based on gDPR may be partially associated with circulating concentrations of P4, the incidence of atypical phenotypes during the estrous cycles, and to a lesser extent the follicular wave dynamics. The observed physiological and endocrine phenotypes might help explain part of the differences in reproductive performance between cows of superior and inferior genomic merit for fertility.

Local embryo-mediated changes in endometrial gene expression during embryo mobility in mares.

Prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) are involved in equine embryo mobility throughout the uterus on Days 11-15 (ovulation = Day 0). On a day (Day 12) of maximal embryo mobility in pregnant mares (n = 13) and before luteolysis in nonbred mares (n = 10), gene expressions were compared between the uterine horns that did and did not contain the mobile embryo and between pregnant and nonbred mares. A cytobrush was used to collect an endometrial sample from the middle of each uterine horn. In nonbred mares, there was no difference for any of the considered gene expressions between the uterine horn ipsilateral and contralateral to the CL or for side (left vs right). For endometrial estrogen receptors, ESR1 was lower (P < 0.03) and ESR2 was greater (P < 0.04) for pregnant than nonbred mares. The mRNA abundance for PGE2 synthase (PTGES) was greater (P < 0.05) in the horn with (1.40 ± 0.10) than without (0.89 ± 0.10) the embryo and was greater (P < 0.05) in the horn with the embryo than in the combined horns of nonbred mares (1.06 ± 0.10). The hypothesis that the embryo locally upregulates PGE2 and PGF2α synthesis in the endometrium adjacent to the embryo in the pregnant group but not in the uterine horns of the nonbred group, was partially supported; only PGE2 synthase (PTGES) was locally upregulated in the endometrium adjacent to the mobile embryo.

Concentrations of progesterone and a PGF2α metabolite during the interovulatory interval compared to the corresponding days of pregnancy in mares.

The concentrations of progesterone (P4) and a metabolite of PGF2α (PGFM) in mares were compared between the interovulatory interval (IOI; n = 8) and the corresponding days of pregnancy (n = 9). In daily blood samples, P4 increased between the day of ovulation (Day 0) and ∼Day 6 and then gradually decreased until the beginning of luteolysis in the IOI group. Before the beginning of luteolysis, there were no significant differences in P4 concentrations between the IOI and early pregnancy. In the IOI, PGFM concentration on the day before the beginning of luteolysis began to increase (P < 0.04) and reached a maximum mean (42.9 ± 11.6 pg/mL) on Day 14. In pregnancy, a novel increase in PGFM occurred from Day 12 to a maximum mean on Day 15 (16.7 ± 3.1 pg/mL). Daily PGFM concentrations were not different between the two groups until the increase just before luteolysis in the IOI. During 8-h sessions of hourly blood sampling, the mean and maximum PGFM concentrations were significantly greater in IOI than in pregnancy for each 8-h session on Days 13, 14, and 15. The minimum was not different between groups on any day. Pulses of PGFM were identified by coefficient of variation during the hourly 8-h sessions on day-sets of Days 4-7, 9-11, and 13-16. Despite the PGFM increase in daily samples between Days 12 and 15 of pregnancy, the amplitude and peaks of CV-identified pulses did not differ in the pregnant mares among the three day-sets. The pulses were similarly small for day-sets 4-7 and 9-11 in the IOI and for all day-sets in pregnancy (eg, amplitude on Days 13-16: 43.4 ± 15.6 pg/mL vs 5.4 ± 1.1 pg/mL for IOI vs pregnancy). Hypothesis 1 was not supported that daily PGFM concentrations in an IOI increase at the intersection between the end of the rapid P4 increase and the gradual P4 decrease. Hypothesis 2 was supported that pregnant mares have low amplitude PGFM pulses during the days of the high amplitude pulses at luteolysis in the IOI.

Early pregnancy diagnosis at 21 days post artificial insemination using corpus luteum vascular perfusion compared to corpus luteum diameter and/or echogenicity in Nelore heifers.

The objective was to compare the use of corpus luteum (CL) vascular perfusion to CL diameter and/or echogenicity to diagnose pregnancy at 21 d after timed-AI. Ovaries of Nelore heifers were assessed using ultrasonography in B-mode and color Doppler simultaneously 21 d after timed-AI (n = 113). Objective evaluations were performed using an image processing software to extract the number of colored pixels (ColorPix), diameter (mm) and echogenicity/mm² (EchoPix) of the CL. Subjective evaluations of the CL were performed by five evaluators using scores of estimated vascular perfusion area of color Doppler scan videos and estimated CL size and qualitative echogenicity of B-mode scan videos. The reference pregnancy diagnosis was performed 33 d after timed-AI using an ultrasonic device. Corpus luteum ColorPix, diameter and EchoPix were highly correlated (P < 0.001) with pregnancy. Pregnancy diagnosis accuracy, sensitivity, and negative predictive value were not different for CL ColorPix and diameter and was less with use of EchoPix compared to the other parameters. Size and vascular perfusion scores were correlated to the greatest extent (0.88-0.94) with the respective objective values within evaluator. The results from the ROC curve analysis indicated a smaller area under the curve for qualitative echogenicity compared to CL size and vascular perfusion. Corpus luteum vascular perfusion was the only subjective evaluation that when assessed there were no false negative pregnancy diagnoses. In conclusion, the use of the objective CL diameter resulted in the same efficacy as CL vascular perfusion evaluations for early pregnancy diagnosis in Nelore heifers.

Endogenous and exogenous effects of PGF2α during luteolysis in mares.

An inhibitor of PGF2α biosynthesis (flunixin meglumine, FM) was used to study the role of endogenous PGF2α on the luteolytic effect of exogenous PGF2α in mares. A 2-h infusion of PGF2α at a constant rate (total dose, 0.1 mg) on Day 10 (ovulation = Day 0) was used to mimic the maximal concentrations of a spontaneous pulse of a PGF2α metabolite (PGFM). Treatment with FM (1.7 mg/kg) was done 1 h before and 5 h after the start of PGF2α infusion. In hourly blood samples beginning 1 h before the start of PGF2α infusion, progesterone decreased (P < 0.05) similarly by 5 h in each of the PGF2α and PGF2α+FM groups but not in the controls (n = 5). In a study of spontaneous luteolysis, the same FM dose was given every 6 h from Day 13 until Day 17 or earlier if CL regression was indicated by an 80% decrease in luteal blood-flow signals. Blood was sampled for progesterone assay each day and 8 h of hourly blood sampling was done each day to characterize PGFM concentrations and pulses. Progesterone (P4) was lower (P < 0.05) in controls than in an FM group (n = 7) by Day 15. Luteolysis (P4 < 1 ng/mL) ended on Days 14-19 in individual controls. In contrast, luteolysis did not end until after Day 20 in 4 of 7 FM-treated mares. In the three mares with completion of luteolysis before Day 20 in the FM group, the interval from beginning to end of luteolysis was longer (P < 0.02) (4.5 ± 0.6 days) than in the controls (3.0 ± 0.4 days). During 8-h sessions of hourly blood sampling on Day 14, concentration of PGFM was significantly lower in the FM group for the minimal, mean, and maximal per session. Pulses of PGFM were identified by a CV methodology on each day in 7 of 7 and 3 of 7 mares in the controls and FM group, respectively. The four FM-treated mares without a CV-identified pulse were the four mares in which luteolysis did not occur before Day 20. In mares with detected pulses, PGFM was lower at each nadir and at the peak (86% lower) in the FM group than in controls, but the interval between nadirs or base of a pulse was not different between groups. Hypothesis 1 that endogenous PGF plays a role in the luteolytic effect of exogenous PGF2α was not supported. Hypothesis 2 that an inhibitor of PGF2α biosynthesis prevented or minimized the prominence of PGFM pulses and increased the frequency of persistent CL was supported.

Follicle blood flow and FSH concentration associated with variations in characteristics of follicle selection in heifers.

Selection of the dominant follicle during a follicular wave is manifested by diameter deviation. At deviation (day 0), growth rate continues for the future dominant follicle (F1) and begins to decrease for the largest subordinate follicle (F2). The percentage of color-Doppler blood-flow signals in the wall of F1 and F2 and the temporality between FSH concentration and F1 and F2 diameter were determined daily in waves 1 and 2 in 24 Holstein heifers. Diameter and blood flow were compared among classes of deviation: (1) conventional (F2 ≥ 7.0 mm on day 0), (2) F2-undersized (F2 < 7.0 mm on day 0), and (3) F1,F2-switched (F2 larger than F1 on days -1 or 0). A class-by-day interaction for diameter of F2 (P < 0.004) and for blood-flow percentage of F2 (P < 0.02) represented greatest values on days -1 or 0 in the switched class and greater values in the conventional than undersized class. Changes were similar between diameter and blood flow in F1 and F2 before deviation. Blood flow in F2 decreased sooner than diameter after deviation indicating that a decrease in vascular perfusion preceded a decrease in diameter. Relationships between F1 and FSH in conventional deviation were similar between waves 1 and 2 for (1) growth rate of F1 on days -1 to 0, (2) interval from emergence of F1 at 4 mm to deviation, and (3) decrease in FSH on days -2 to 0. Relationships between F2 diameter and FSH were dissimilar between classes and between waves 1 and 2 indicating other hormones or factors are also involved in the complex control of F2. For example, the growth rate of F2 was greater (P < 0.05) for conventional than undersized class during wave 1 but similar between classes during wave 2. The FSH surge 2 was similar in profile and prominence between classes but the interval from the FSH peak of surge 2 to deviation was shorter (P < 0.05) in the undersized class (1.5 ±â€¯0.3 d) than in the conventional class (2.3 ±â€¯0.3 d). This was a novel finding and accounted for some of the dissimilarities in growth rate of follicles between classes in wave 2. Results did not support the hypothesis that the extent of blood flow in the wall of future dominant and largest subordinate follicles before deviation is an earlier indicator of follicle destiny than diameter. Results supported the hypothesis that follicle dynamics and FSH concentrations before deviation are temporally associated within conventional and undersized deviation classes but the temporality differs between classes.

Gonadotropin concentrations associated with variations in diameter deviation during follicle selection in Holstein heifers.

Diameter deviation or selection of the future dominant follicle (F1) from the future largest subordinate follicle (F2) during a follicular wave occurs when F1 is 8.5 mm (expected deviation, day 0). Deviation has been classified as conventional (F2 ≥ 7.0 mm), F2-undersized (F2 < 7.0 mm), and F1,F2-switched (F2 larger than F1 on day -1 or 0). Concentrations of gonadotropins were compared within and among deviation classifications in waves 1 and 2 in 48 heifers. A three-way (wave 1 compared with 2, classification, day) analysis indicated no effect of wave 1 compared with 2 on F2 or FSH. An interaction of classification by day for F2 diameter (P < 0.001) and FSH concentration (P < 0.005) was primarily from differences on day -1. Rankings on day -1 from greatest to least for F2 diameter were switched, conventional, and undersized and for FSH concentration were undersized, conventional, and switched. Lower FSH concentration in conventional compared with undersized deviations during the decline in the FSH surge was presumed to represent greater output of FSH inhibitors by larger follicles. The incline in FSH surge 2 began significantly later for undersized than for conventional deviation. Switched deviation was associated significantly with emergence of F2 before F1, lower FSH concentration during the decline in the FSH surge, and earlier occurrence of the post-surge FSH nadir. Results supported the hypothesis that diameter differences among deviation classifications are temporally associated with differences in FSH concentration within each classification. These novel findings may complicate studies on the mechanisms of follicle selection.

Angiocoupling between the dominant follicle and corpus luteum during waves 1 and 2 in Bos taurus heifers.

The local two-way effect of the future and established dominant follicle (DF) and corpus luteum (CL) on color-Doppler signals of blood flow on each other (angiocoupling) was studied from ovulation to 16 days after ovulation during wave 1 and for the first time in wave 2 in Bos taurus heifers (N = 24). Identity of follicles greater than 4 mm was maintained from day to day. Blood-flow signals in the follicle wall and in the CL were estimated after scanning the entire structure. Ovarian patterns were defined based on the presence of a DF and CL: DF-CL pattern (DF and CL in the same ovary), DF pattern or CL pattern (DF and CL in opposite ovaries), and devoid pattern (neither DF nor CL). Comparisons were made of blood flow in each structure when in the same ovary vs opposite ovaries. Data were normalized to expected diameter deviation (DF closest to 8.5 mm). Blood-flow signals were detected in most growing follicles when they attained 6 mm (6.0-6.9 mm). Combined for waves 1 and 2, the percentage of all 6-mm growing follicles that displayed blood-flow signals was greater (P < 0.0001) for the DF-CL pattern (21/26, 81%) than for the patterns of DF alone, CL alone, or neither DF nor CL (total for the three patterns (17/42, 40.5%); there was no effect of left vs right ovaries. For each wave, the percentage of DF wall and percentage of CL tissue with blood-flow signals were greater for the DF-CL pattern vs the DF pattern or CL pattern. Percentage of DF wall with blood-flow signals for the DF-CL vs DF patterns was 30.0 ±â€¯1.5% vs 19.5 ±â€¯1.1% (P < 0.02) in wave 1 and 30.8 ±â€¯1.3% vs 20.2 ±â€¯1.1% (P < 0.0001) in wave 2. Percentage of CL tissue with blood-flow signals for the DF-CL vs CL patterns was 61.7 ±â€¯2.4% vs 56.9 ±â€¯1.7% (P < 0.03) in wave 1 and 78.8 ±â€¯1.3% vs 74.0 ±â€¯0.9% (P < 0.03) in wave 2. During wave 1, the percentage of CL tissue with blood-flow signals was greater (P < 0.002) when the DF and CL were in close proximity (distance between structures, < 2 mm; 66.9 ±â€¯3.0%) than when separated (≥2 mm; 53.8 ±â€¯3.5%). Normalization to the maximal DF diameter in wave 1 resulted in the novel finding that the percentage of blood-flow signals in the DF wall began to decrease 1 day before maximal diameter. Results supported the hypotheses that (1) percentage of DF wall and CL tissue with blood-flow signals in wave 2 is greater in the DF-CL pattern than in the DF or CL patterns and (2) percentage of DF wall with blood-flow signals in wave 1 decreases before the beginning of a decrease in diameter.

Concentrations of follicle stimulating hormone associated with follicle selection, number of follicles, and ipsilateral vs contralateral relationships in mares.

Diameter deviation or follicle selection during a follicular wave begins with continuous growth rate of F1 (dominant or selected follicle; DF) and decreasing growth rate of F2 (largest subordinate). Intraovarian patterns based on presence or absence of the DF and CL are DF-CL, DF, CL, and devoid (neither DF nor CL). The DF and CL relationships in a pair of ovaries are ipsilateral (DF-CL pattern and devoid pattern) and contralateral (DF pattern and CL pattern). The effects of patterns and relationships on F1, F2, and FSH during deviation were determined in 21 mares. Diameters of F1 and F2 at expected beginning of deviation (F1, 22.5 mm; day 0) defined deviation classifications of conventional (F2 ≥ 18.5 mm on day 0), F2-undersized (F2 < 18.5 mm), and F1,F2-switched (F2 larger than F1 on day -1 or 0). During the decline in the FSH surge, an interaction (P < 0.001) of deviation classification and day indicated that FSH concentration was greater (P < 0.05) in undersized than in conventional deviations on days -3 and -1 and intermediate in switched deviation. Low FSH during days -3 to -1 in switched deviation began to increase on day -1 during switching in diameter rank between F1 and F2. The number of subordinate follicles per wave that attained a maximum of 11 to <16 mm was greatest in the DF-CL and devoid patterns and in ipsilateral (4.2 ±â€¯0.5 follicles) than in contralateral (2.5 ±â€¯0.7) relationships (P < 0.03). Concentration of FSH was greater (P < 0.04) on days -4 to 5 in ipsilateral (5.3 ±â€¯0.2 ng/mL) than in contralateral (4.2 ±â€¯0.4 ng/mL) relationships consistent with more follicles 11 to < 16 mm. In a survey (N = 63), an ipsilateral vs contralateral relationship was associated with 17 vs 17 conventional deviations and 7 vs 22 nonconventional deviations (P < 0.04), and conventional deviation (54%) was more frequent (P < 0.0001) than undersized (21%) or switched (25%) deviations. Results supported the hypotheses that (1) diameter deviation can be classified in mares into distinct categories based on diameter and rank of the future largest subordinate at expected deviation, (2) the number of subordinate follicles is influenced by ipsilateral vs contralateral relationships of DF and CL, and (3) conventional deviation is more common when the relationship between DF and CL is ipsilateral. Knowledge on follicle diameters for the different deviation classifications should be considered in studying follicle selection especially when terminal follicle sampling is done before expected deviation.

Human introduction or natural dispersion? Atlantic Ocean occurrence of the Indo-Pacific whitetip reef shark Triaenodon obesus.

Occurrence of multiple whitetip reef sharks Triaenodon obesus in the Atlantic Ocean is reported for the first time from near a sunken ferry off the Paraná coast in south-eastern Brazil. This occurrence is hypothesized to have been caused by either a human introduction or a remarkably long oceanic displacement.

Blood flow and echotextural differences between the future dominant and subordinate follicles before the beginning of diameter deviation in heifers.

Diameter deviation is the beginning of a decrease in growth rate of the largest subordinate follicle (SF) and a continuing growth rate of the dominant follicle (DF). In wave 1 in cattle, deviation begins 2 or 3 days after ovulation when the future DF is about 8.5 mm. Gray scale and power-flow Doppler ultrasound examinations were done in experiment 1 (daily examinations, n = 13) and experiment 2 (examinations every 8 h, n = 15). Blood flow and an anechoic layer in the follicle wall were normalized to the beginning of diameter deviation (day 0 or hour 0). Only waves with conventional diameter deviation (68% of waves) were used as identified by: (1) future SF greater than 7.0 mm when DF was 8.5 mm and (2) future DF and SF did not switch in diameter rank. In experiment 1, deviations in the extent of blood-flow signals and in the extent of anechoic layer began on the same day as deviation in diameter. In experiment 2, deviations in diameter, surface area (πd2), and anechoic layer began in synchrony, and deviation in blood-flow signals began 16 h earlier. Blood-flow deviation before diameter deviation was shown by (1) a first difference (P < 0.02) between follicles at hour -16 and (2) development during the hours -24 to 0 of a greater (P < 0.05) percentage difference between follicles in blood-flow signals (11.1 ± 2.3%) than in surface area (7.4 ± 0.7%) or diameter (4.5 ± 0.4%). Results supported the hypothesis that the extent of blood flow in the future dominant and subordinate follicles deviates before diameter deviates. A similar hypothesis for anechoic layer was not supported; diameter and anechoic layer deviated in synchrony.

Five new records of Luvarus imperialis (Acanthuroidei: Luvaridae) in the south-west Atlantic Ocean.

Five new records of louvars Luvarus imperialis are documented for the south-west Atlantic Ocean, extending its distribution range in this ocean. The presence of one ripe specimen, associated with the previous records of larvae and juveniles, suggests that L. imperialis spawn in this region. The possible association of juveniles with shoals of skipjack tuna Katsuwonus pelamis is discussed.

Acidulated phosphate fluoride application changes the protein composition of human acquired enamel pellicle.

We evaluated, by proteomic analysis, whether the chemical changes provoked on enamel by acidulated phosphate fluoride (APF) application alter the protein composition of acquired enamel pellicle. Enamel slabs, pretreated with distilled water (negative control), phosphoric acid (active control) or APF solution, were immersed in human saliva for pellicle formation. The adsorbed proteins were extracted and analyzed by liquid chromatography-mass spectrometry/mass spectrometry. Fifty-six proteins were identified, 12 exclusive to APF and 11 to phosphoric acid. APF decreased the concentration of histatin-1, but increased the concentration of S100-A9, which is confirmed by immunoblotting. The findings suggest that APF application changes the acquired enamel pellicle composition.