Biosensor capability of the endometrium is mediated in part, by altered miRNA cargo from conceptus-derived extracellular vesicles.

We tested the hypothesis that the biosensor capability of the endometrium is mediated in part, by the effect of different cargo contained in the extracellular vesicles secreted by the conceptus during the peri-implantation period of pregnancy. We transferred Bos taurus taurus embryos of different origin, in vivo (high developmental potential (IV)), in vitro (intermediate developmental potential (IVF)), or cloned (low developmental potential (NT)), into Bos taurus indicus recipients. Extracellular vesicles (EVs) recovered from Day 16 conceptus-conditioned medium were characterized and their microRNA (miRNA) cargo sequenced alongside RNA sequencing of their respective endometria. There were substantial differences in the endometrial response to in vivo versus in vitro and in vivo versus cloned conceptuses (1153 and 334DEGs respectively) with limited differences between in vitro Vs cloned conceptuses (36 DEGs). The miRNA cargo contained in conceptus-derived EVs was similar between all three groups (426 miRNA in common). Only 8 miRNAs were different between in vivo and cloned conceptuses, while only 6 miRNAs were different between in vivo and in vitro-derived conceptuses. Treatment of endometrial epithelial cells with mimic or inhibitors for miR-128 and miR-1298 changed the proteomic content of target cells (96 and 85, respectively) of which mRNAs are altered in the endometrium in vivo (PLXDC2, COPG1, HSPA12A, MCM5, TBL1XR1, and TTF). In conclusion, we have determined that the biosensor capability of the endometrium is mediated in part, by its response to different EVs miRNA cargo produced by the conceptus during the peri-implantation period of pregnancy.

Comparing the effect of estradiol benzoate and 17ß-estradiol plus progesterone on follicular turnover and development, and pregnancy outcomes in a timed artificial insemination protocol.

The objective of this study was to compare the efficiency of estradiol benzoate (EB) and 17ß-estradiol (E2) associated with progesterone (P4) in a fixed-time artificial insemination (FTAI) protocol. We hypothesized that E2+P4 induces an earlier emergence of a new follicular wave (NFW), improving pre-ovulatory follicle diameter and pregnancy rates to FTAI (P/FTAI). In Exp.1, on Day 0 (D0), all Bos indicus cows (n = 12/group) received an intravaginal P4 device and a dose of PGF2α analogue. On D0, females were randomly assigned to receive EB or E2+P4. On D8.5, P4 intravaginal devices were removed and a dose of PGF2α and EB were administered in all females followed by fixed-timed AI on D10. Between D0 and D10, the dominant follicular growth was determined by ovary ultrasonography exams. On D8.5 and D10 the percentage of color power-Doppler signals in the dominant follicular wall was evaluated. In Exp. 2, 467 females (2-year-old nulliparous [n = 76], primiparous [n = 92] and pluriparous [n = 299]) were subjected to the similar FTAI and assigned to be treated with EB (n = 243) or E2+P4 (n = 224). Pregnancy diagnosis was performed 30 days after FTAI by ultrasonography. The day to emergence of NFW was similar between treatments (EB: 3.7 ± 0.37 vs. E2+P4: 3.3 ± 0.3, P = 0.76). Females treated with E2+P4 presented greater (P = 0.06) follicular growth between the emergence and D9 (1.18 ± 0.07) than those treated with EB (0.97 ± 0.08). There was also a positive effect (P < 0.05) of E2+P4 on diameter of the dominant follicle on D9 (13.0 ± 0.6 vs. 10.9 ± 0.55) and blood perfusion of the follicle wall on D8.5 (49 vs. 40%). There was a treatment by parity category interaction effect on P/FTAI (P < 0.05). Treatment with E2+P4 was advantageous to P/FTAI of primiparous cows (E2+P4: 58% and EB: 30%). However, for nulliparous and pluriparous cows, P/FTAI was similar between treatments (∼50%). In conclusion, in a E2/P4-based protocol for FTAI, E2+P4 is as efficient as EB in inducing new follicular emergence within a similar day range, but it results similar or greater P/FTAI.

Comparison of estradiol benzoate doses for resynchronization of ovulation at 14 days after timed-AI in suckled beef cows.

We aimed to compare the effects of use of 1 or 2 mg estradiol benzoate (EB) associated with an intravaginal progesterone (P4) device for resynchronization of ovulation 14 days after timed-AI (TAI) in suckled beef cows. Nelore cows were submitted to a TAI (D0) and on D14, received an intravaginal P4 device and were randomly assigned to EB-1 group [n = 516] or EB-2 group [n = 510], which that received 1 or 2 mg EB, respectively. Also, cows had the ovaries scanned by ultrasound to detect an active CL on D14. On D22, devices were removed and structural luteolysis was detected by color-Doppler ultrasonography. In cows which underwent luteolysis, the resynchronization protocol was continued and they were submitted to second TAI on D24. Pregnancy diagnosis was performed 30-35 days after first or second TAI. A subgroup [n = 18-19/group] was submitted to daily ovarian ultrasound scanning from D14 to D22. Proportion of cows with an active CL on D14 did not differ (P > 0.1) between EB-1 and EB-2 groups. The proportion of cows with an active CL on D22 and pregnancy per AI (P/AI) at first TAI were greater (P ≤ 0.05) in EB-1 (55% and 51%) than in EB-2 group (48% and 42%). The P/AI at second TAI did not differ (P > 0.1) between EB-1 (47% [106/227]) and EB-2 group (42% [110/259]). Cumulative pregnancy rate was greater in EB-1 (73% [370/508]) than in EB-2 group (64% [322/502]). No difference (P > 0.1) was observed in the proportion of non-pregnant cows with a synchronized follicular wave emergence between EB-1 and EB-2 groups. In conclusion, treatment with either 1 or 2 mg EB associated with an intravaginal P4 device at D14 after TAI are efficient to synchronize a new follicular wave emergence. The decreased P/AI from first TAI observed in the group of cows receiving 2 mg indicates that this dose is not recommended for use in resynchronization programs initiated 14 days after TAI. The use of 1 mg EB associated with a P4 device provides an elevated cumulative pregnancy rate after two TAIs with an interval of 24 days.

Early resynchronization of follicular wave emergence among Nelore cattle using injectable and intravaginal progesterone for three timed artificial inseminations.

Follicular dynamics and pregnancy per AI (P/AI) of cattle submitted to resynchronization 13 d after TAI using a progesterone (P4) insert and supplementary injectable progesterone (iP4) were determined. There was synchronization of ovulation timing imposed (Day 0 = expected estrus; Experiment 1). On Day 13, animals were assigned to: control (only P4 insert; 15 cows and 13 heifers) and iP4 (P4 insert+100 mg iP4; 13 cows and 12 heifers) groups, and submitted to daily ovarian ultrasonography and blood collection (Day 13 to Day 22). In Experiment 2, 760 suckled cows and 498 heifers were submitted to a TAI on Day 0 and assigned into control and iP4 groups on Day 13. In animals with luteolysis on Day 22, there was a second TAI on Day 24, and on Day 37 were subjected to the opposite treatments as imposed in first resynchronization procedure. On Day 37, there was pregnancy diagnosis in animals with functional CL. The third TAI was performed on Day 48. Day of follicular wave emergence did not differ between groups and parities. Dominant follicles were larger in cows than heifers, and in animals of the control group on Day 24. Greater P4 concentrations were detected on Day 14 and Day 15 in the iP4-treated animals. Luteolysis occurred earlier in cows than heifers. Overall P/AI percentage as a result of second and third TAIs, regardless of parity, was greater in iP4-treated animals. In conclusion, females treated with a supplementary iP4 had a greater plasma P4 concentration and P/AI, but there was no effect of iP4 treatment on synchrony of timing of follicular wave.

Early pregnancy-induced transcripts in peripheral blood immune cells in Bos indicus heifers.

Immune cells play a central role in early pregnancy establishment in cattle. We aimed to: (1) discover novel early-pregnancy-induced genes in peripheral blood mononuclear cells (PBMC); and (2) characterize the temporal pattern of early-pregnancy-induced transcription of select genes in PBMC and peripheral blood polymorphonuclear cells (PMN). Beef heifers were artificially inseminated on D0 and pregnancies were diagnosed on D28. On D10, 14, 16, 18, and 20, blood was collected for isolation of PBMC and PMN from heifers that were retrospectively classified as pregnant (P) or non-pregnant (NP). PBMC samples from D18 were submitted to RNAseq and 220 genes were differentially expressed between pregnant (P) and non-pregnant (NP) heifers. The temporal abundance of 20 transcripts was compared between P and NP, both in PBMC and PMN. In PBMC, pregnancy stimulated transcription of IFI6, RSAD2, IFI44, IFITM2, CLEC3B, OAS2, TNFSF13B, DMKN and LGALS3BP as early as D18. Expression of IFI44, RSAD2, OAS2, LGALS3BP, IFI6 and C1R in PMN was stimulated in the P group from D18. The novel early-pregnancy induced genes discovered in beef heifers will allow both the understanding of the role of immune cells during the pre-attachment period and the development of technologies to detect early pregnancies in beef cattle.

Use of Doppler ultrasonography in embryo transfer programs: feasibility and field results.

The intensive use of Doppler ultrasonography in several studies in the last decade allowed the characterization of vascular perfusion and the estimation of function of the reproductive organs and tissues along the estrous cycle and pregnancy in cattle. We aim to discuss the possibility of using Doppler imaging and to explore the potential of its inclusion in reproductive programs in cattle industry. Recent studies in dairy and beef cows indicated a high accuracy and sensitivity when Doppler ultrasonography is used to evaluate corpus luteum function and to diagnosis pregnancy between days 20 and 22. Moreover, resynchronization programs starting 5 to 7 days after timed embryo transfer (FTET) coupled with early pregnancy diagnosis were developed for beef cattle, and have been implemented in commercial embryo transfer programs. These strategies allow a reduction in the interval between two FTET from ≈ 40 to 24 days and may improve the gains in reproductive efficiency when compared to traditional programs than begin resynchronization after the pregnancy diagnosis at 30 days. A second alternative to use Doppler imaging is the evaluation of luteal blood perfusion at the time of embryo transfer for selection of recipients with greater receptivity potential. This may increases fertility in FTET, as embryos would not be transferred to females with non-functional CL, and in cases with recipients surplus, females with higher receptivity would be prioritized.

Unusual caudal vena cava thrombosis in a cow, secondary to Trueperella (Arcanobacterium) pyogenes infection / Rara trombose da veia cava caudal em bovino, secundária à infecção por Trueperella (Arcanobacterium) pyogenes

The caudal vena cava thrombosis, or pulmonary thromboembolism, in cattle is correlated with lactic acidosis, caused by diets rich in grains and highly fermentable, associated or not to septic situations, used in feedlots of beef or high-producing dairy cattle. This paper reports an unusual caudal vena cava thrombosis in a cow, secondary to Trueperella (Arcanobacterium) pyogenes infection, resulting in reduced milk production, anorexia, pale mucous membranes, ruminal atony, sternal decubitus and autoauscultation position. The heart was enlarged at necropsy, presence of clots distributed along the thoracic cavity, adherence between lung and pleura, abscesses, emphysema, petechiae, suffusions and ecchymosis in lungs, thickening of the caudal vena cava wall, hepatomegaly with chronic passive congestion ("nutmeg" aspect), and rumenitis. In lab, the actinomycete Trueperella (Arcanobacterium) pyogenes was isolated from liver and lung samples, probably resulting through dissemination of the bacteria of the rumen content, what reaffirms the opportunistic behavior of this actinomycete.(AU)

A síndrome da veia cava caudal ou tromboembolismo pulmonar bovino está relacionada à acidose láctica causada por dietas ricas em grãos e altamente fermentáveis, associados ou não a quadros sépticos, usadas em confinamentos de bovinos de corte ou para vacas leiteiras de alta produção. O presente artigo reporta caso raro de trombose da veia cava caudal em uma vaca, secundária a infecção por Trueperella (Arcanobacterium) pyogenes, apresentando reduzida produção de leite, anorexia, palidez de mucosas, atonia ruminal, decúbito esternal e posição de autoauscultação. À necrópsia observou-se coração aumentado de tamanho, coágulos distribuídos por toda cavidade torácica, aderência entre os pulmões e pleura, abscessos, enfisema, petéquias, sufusões, equimoses nos pulmões, espessamento da parede da veia cava caudal com trombo, hepatomegalia com congestão passiva crônica (aspecto de "noz moscada"), e ruminite. Em laboratório isolou-se o actinomiceto Trueperella (Arcanobacterium) pyogenes a partir de amostras de fígado e pulmão, provavelmente resultando da disseminação da bactéria proveniente do conteúdo ruminal, e reafirma o comportamento oportunista deste actinomiceto.(AU)