Brief Summary of Minutes of Annual Meeting

W4112

Reporting period: 10/1/2020 to 9/30/2021

Meeting Date: May 17 and 18, 2022

Accomplishments

Progress and Important Discoveries by W4112 Objectives

Objective 1 Elucidate fundamental cellular, physiological, endocrine, and behavioral mechanisms that regulate gamete development and quality and enhance the management of reproductive function leading to development of translational reproductive biotechnologies.

Evidence was produced that preantral follicles, although not FSH-dependent, express FSH receptors and the cellular machinery necessary to respond to FSH, and the supplementation of high doses of FSH enhances growth of preantral follicles within the ovarian cortex. (California)

Phenotypically, the SLICK1 mutation is associated with a short, slick hair coat and confers increased thermotolerance. In SLICK1 carrier animals, the JAK/STAT signaling via pSTAT3 might be reduced in hair follicles, which may affect downstream gene transcription. However, the presence of the SLICK1 allele could provide an advantage to reproductive efficiency of Holstein heifers by improving the rate of pregnancy to first service compared to non-carrier animals. (California)

Development of bovine fluid tests to distinguish open from pregnant cows. Concept studies have been completed testing the accuracy of an early ≤ day 18 Open Cow Test (OCT) test for pregnancy status and are in the middle of a 1,000-cow clinical trial. (Colorado)

A marker for selection of in vitro derived embryos, this marker is differently expressed in morphologically (IETS scoring system) good compared to bad day 5, 6 and 7 bovine in-vitro derived embryos. Use of this marker to select the best embryos may improve embryo transfer rates in IVF-derived embryos in cows and possibly in humans. (Colorado)

SNP associated with fertility have been identified based on gene expression in the corpus luteum, endometrium, embryo, white blood cells and milk. (Colorado)

The secretory pattern of LH in response to E2 (25 µg IM) was determined in normal weight, obesity and lean body weight, and revealed a profound alteration associated with obesity characterized by a blunted and delayed LH surge. Upon returning to normal weight, normal LH surge dynamics were re-established. The results also show that return to normal weight in ewes restores peak LH concentration and timing of the LH surge. (Colorado)

Use of sperm health-reflecting biomarkers with high throughput image-based flow cytometry (IBFC) and artificial intelligence, deep learning analysis as a method to create bioimage algorithms that can detect sperm acrosome health status (reflected by lectin PNA-Cy5) on brightfield images alone. (Iowa)

Bull breed appears to have little influence on sperm quality assessments among yearling bulls meeting threshold requirements for passing breeding soundness evaluation exams. However, reactive oxygen species proved to have a detrimental effect on spermatozoa function. (Kansas)

Altered carbohydrate metabolism within the cumulus-oocyte complex likely contributes to the decreased competency of oocytes from small pre-ovulatory follicles exposed to an exogenous GnRH-induced gonadotropin surge. (ARS-Montana)

Systemic inflammation or inability of red blood cells to carry oxygen may contribute to delayed puberty. (Nebraska)

Vascular Endothelial Growth Factor A (VEGFA) isoforms (mainly angiogenic VEGFA165) can rescue the Polycystic ovary syndrome-like phenotypes in High A4 cows. Naturally occurring High A4 cows are present in beef and dairy herds in the US and other countries. (Nebraska)

Feeding spent hemp biomass to rams did not significantly affect total testicular weight, seminiferous tubule diameter, or DAZL immunoexpression. (Oregon)

Pramel1 is required to maintain normal spermatogenesis by regulating germ cell differentiation in response to retinoic acid signaling. (Pennsylvania)

Progesterone receptor membrane component (PGRMC) 1 and PGRMC2 are essential for spermatogenesis and male fertility. It is proposed that PGRMC proteins play essential and multifaceted roles in spermatogenesis during mitosis, meiosis and spermatid elongation. These studies offer the first in vivo insights into the functional role of PGRMC proteins in male gametogenesis. (Wyoming)

The value of a breeding soundness evaluation as evidenced by ram fertility is still lacking. Passing a breeding soundness evaluation did not seem indicative of field fertility in rams. (Wyoming)

Objective 2 Identify impacts of reproductive management, animal management and stress on follicle recruitment, ovulation, corpus luteum function, and pregnancy.

Oral exposure to a mixture of phthalates reduces IGF1 content and significantly disrupts the ovarian antral follicle proteome. Intrafollicular IGF1 was significantly increased in the pre-antral follicles of mice treated with the Phthalate mixture, the effects were also visible in a dose-dependent manner. (Arizona)

Cow-calf herds from the same base genetics are exposed to two different management systems: graze irrigated pastures (IRR) year-round with hay and supplement, and sagebrush steppe range (RAN) from May – December then they are managed similarly to the IRR group. Analysis of animal performance in these systems over the past 5 years demonstrated a reduction in calf growth, cow body weight and cow body condition in the RAN system compared with the IRR system. These results indicate significant differences in nutritional exposure during the first two trimesters of gestation and early calf life. (Idaho)

Energy restrictions after AI had slight negative effects on embryo developmental stage, quality and blastomeres on d 6 and d 7 without affecting progesterone or IGF-1 concentrations in plasma. Post-AI energy restriction reduced Ca and S concentrations and embryo presence reduced Mg and S concentration in flush media. Post-AI nutrient restriction for 14 days revealed similar plasma concentration of protein, glucose, cholesterol, and progesterone across diet, but NEFA was elevated among nutrient restricted heifers. When an embryo was recovered, Mg and S were decreased in uterine flush media. (ARS-Montana)

Work is undergoing to identify cell types, issues, and biological pathways that are sensitive to the maternal diet, and results will be used to develop strategic supplementation strategies to improve embryo development and pregnancy retention following periods of maternal dietary stress. (Montana)

Excess steroid production can be a major factor that causes anovulation in cattle populations. (Texas A&M, Arizona, MS)

Luteolysis is associated with metabolic pathways that reduce mitochondrial energy production, stimulate free radicals and collagen synthesis and activate immune cells. (New Mexico, Colorado)

Objective 3 Determine mechanisms regulating normal embryo development, pregnancy establishment, and maintenance by exploring maternal and paternal factors, including genomics, immune responses, fetal programming, and conceptus/uterine signaling.

Intrauterine growth restricted (IUGR) fetuses have altered glucose response. Prenatal therapy of both oxygen and glucose normalizes insulin secretion and whole-body glucose fluxes IUGR fetuses. (Arizona)

Evidence has been produced that IUGR presents sexually dimorphic programing of obesity, where males that had experience fetal growth restriction presented fewer fat cells compared to controls, and these effects were not observed in females. (Arizona)

An in vivo RNA interference (RNAi) within the sheep placenta was developed to examine the function and relative importance of genes involved in conceptus development (PRR15 and LIN28), placental nutrient transport (SLC2A1 and SLC2A3), and the placenta derived hormones (CSH). (Colorado)

The direct actions of CSH are to promote blood flow and nutrient uptake by the uteroplacental unit as present regardless of degree of severity of placental insufficiency, and CSH likely plays a role in modulating placental metabolism that ultimate promotes maximal placental glucose transfer. (Colorado)

Subcutaneous delivery of IFNT protects the ovine corpus luteum from exogenously delivered prostaglandin F2-alpha. mRNA expression of steroidogenic enzymes StAR, HSD3β1, CYP11A1, transcription factors JUN and FOS, and prostaglandin-endoperoxide synthase 2 (PTGS2) were not regulated in the corpus luteum at 48h after PGF2 challenge; however, steady state levels of luteal LHCGR, TNFaIP6, TGFβ2, and XIAP mRNAs were found to be higher in the IFN-infused ewes. (Colorado)

Poor maternal nutrition (over and restricted feeding) impacts metabolic factors and glucose tolerance in sheep offspring. In addition, maternal diet affects hepatic mRNA expression of specific epigenetic factors which may contribute to altered metabolism and liver function. Furthermore, both sperm small RNA composition and expression levels are significantly altered in responses to poor maternal gestational nutrition in sheep. (Connecticut)

Over-feeding during gestation increased meat tenderness, which may be due to reduced collagen cross-linking by lysis oxidase. (Connecticut)

Removal of sperm with damaged acrosomes before freezing improved field fertility in a sire specific manner. (Montana)

Nutrient restriction and melatonin supplementation alter concentrations of neurotransmitters and their metabolites in a seasonally dependent manner. In addition, maternal nutrient restriction in spring calving dams may shift fetal pancreatic islet size from medium to large clusters, while increasing the average size of the cell clusters. Conversely, melatonin supplementation in fall calving dams decreased the average size of the cell clusters, which may alter pancreatic function later in life. (Mississippi)

There are sire-driven effects on embryonic development, embryos from sires with reduced ability to produce embryos (low performing) are delayed in development and have increased arrest at the 5-6 cell stage possibly due to a genetic or non-genetic contribution from the sperm. In addition, embryos from low performing begin development under increased stress, which impacts their ability to undergo cleavage and continue development. Their autophagic response alone is not robust enough to mitigate this stress by the morula stage, preventing a proportion from reaching the blastocyst stage. (Missouri)

Effects of sire are also encountered on placental development, using an in vitro model it is possible to identify sires with limited trophectoderm growth and PAG production that are in higher risk to experience pregnancy loss in the first 40 days of pregnancy. (Missouri)

The addition of FGF2, LIF and IGF1 (FLI) to culture medium increase the proportion of embryos that reach the blastocyst stage. However, by day 15 of development embryos produced under the influence of FLI are developmentally like those produced in control culture medium and thus have the competency to develop into healthy offspring. (Missouri)

IVP-derived male embryos were more susceptible to alterations in gene expression and these effects extend to the peri implantation period including genes associated with placental development. (Missouri)

Preeclampsia sFLT-1 and PLGF remained elevated months later after suppressing CXCL12-CXCR4, suggesting a clear role of CXCL12-CXCR4 signaling during placentation and provide strong evidence that altering CXCL12-mediated signaling during early placentation induces enduring placental effects manifesting later in gestation. In addition, CXCL12 stimulates production of select cytokines, rather than P4 in the CL to assist in CL establishment and survival. (New Mexico)

Restricted- and over-feeding negatively impact protein and mRNA expression of key chemokines and growth factors implicated in proper placenta development and function. (New Mexico)

Parthenogenetic embryos have different secretion patterns and products compared to normal IVF embryos. (Texas)

Repeated PGF2α release may alter steroid hormone production; however, does not negatively affect pregnancy status during the transition period to late embryonic development. (Texas)

The current method to evaluate sire fertility using SCR does not truly represent the field fertility status in these groups of animals evaluated. Large variance in pregnancy loss between days 30 and 60 of gestation were observed among sires and these phenotypes should be considered when evaluating sire fertility in order to increase the score reliability. (Iowa, Missouri, Montana (ARS))

Transcription factor (TCF) 3 and TCF12 are dynamically up-regulated in gonadotrope cells during estrus and are essential for female fertility through their regulation of Lhβ transcription. (Wyoming)

Homeostatic levels of PGRMC1 are fundamentally required for normal gestation. PGRMC protein expression is disrupted in most women’s reproductive diseases. (Wyoming)

There is no negative effect of seminal plasma supplementation on embryo morphology or reproductive performance of offspring. (Wyoming)

Supplementation of 1.8 mM choline chloride to the culture medium does not impact embryo development to the blastocyst stage or pregnancy establishment. (Wyoming)

Collaborations

• Tod Hansen (CSU) will analyze bovine uterine flushings from Texas for Interferon-tau concentrations.
• Tod Hansen (CSU) will analyze bovine fluid samples from Montana (USDA-ARS) for Interferon-tau concentrations.
• Colorado will facilitate transmission electron microscopy and histopathology analysis of sperm compared to high throughput image-based flow cytometry (IBFC) and artificial intelligence, deep learning analysis as methods to evaluate quality of sperm analyzed in Iowa.
• Becky Poole (Texas) and Andrea Cupp (Nebraska) are collaborating on vaginal microbiome and perhaps uterine during puberty and after ovariectomy within our pubertal classification heifers.
• Anna Denicol (California) and Andrea Cupp (Nebraska) are collaborating on collecting ovarian cortex in vivo- California and Nebraska
• Dave Grieger (Kansas) and Andrea Cupp (Nebraska) are collaborating on developing professional development in reproduction for FFA instructors (High School Ag Teachers) and conducting antral follicle counts/ultrasound in heifers- K-State and Nebraska  
• Sofia Ortega (Missouri) and Ky Pohler (Texas A&M) are collaborating on bi parental vs uniparental embryos/pregnancies, PAG ablation effects on pregnancy establishment, and sire effects on pregnancy establishment
• Collaborations are underway with Karl Kerns (Iowa), Tom Geary and Sarah McCoski (Montana) on IVP embryos on pregnancy success
• NMSU will continue to collaborate with the laboratories of Drs. Govoni & Reed at Connecticut investigating the impacts that nutritional stress during gestation has on select chemokines and growth factors and their functions in the placenta using a sheep model.  
• Geary (USDA-ARS, Miles City with Sofia Ortega (Missouri), Sarah McCoski (Montana), & Karl Kerns (Iowa): Embryonic cell differentiation of IVP & conventional embryos as it related to pregnancy success in cattle.
• Geary, Ortega & Kerns: Evaluation of biomarkers on sperm involved with fertility using nano-purification and in vitro development.
• Geary, Kerns, & David Grieger (Kansas): Flow cytometry evaluation of bull semen.
• Geary & McCoski: Effects of heifer nutrition on uterine metabolome and embryonic development.
• Geary & Tod Hansen (Colorado): Early pregnancy diagnosis in beef heifers and cows associated with pregnancy maintenance.
• Geary, Brenda Alexander (Wyoming), & Michelle Kutzler (Oregon): Comparison of the ram breeding soundness evaluation with functional sperm fertility measures using flow cytometer.