Brief Summary of Minutes of Annual Meeting

Short Term Outcomes

  Collaboration with Western Section American Society of Animal Science on planning symposia.

Outputs

 Members of W3112 published:

• 2 book chapters
• 67 peer reviewed journal articles
• 101 abstracts and proceedings papers

Eighteen graduate students completed M.S. theses or Ph.D. disertations conducting research related to the objectives of W3112.

Members of the committee delivered 6 different invited technical presentations presentations to scientists and livestock producers. 

Specific observations from experiments were:

1. Greater STAT3 activity and mitochondrial respiration rates in the cardiac muscle of sheep fetuses with placental insufficiency.
2. Mitochondrial respiration rates are depressed in skeletal muscle of sheep fetuses with placental insufficiency.
3. Detection of MBP in the ovary of treated mice provides further evidence that oral dosing with DBP results in direct effects on the ovary.
4. Understanding how phthalates interact with ovarian follicles and the pathways that regulate follicle function (e.g. growth factor signaling, DNA damage response, apoptosis) will facilitate the management of infertility caused by environmental contaminants.
5. Development of a diagnostic for pregnancy status early during pregnancy would have tremendous economic benefit to producers raising ruminants
6. Discovery of genetic markers for embryo quality, elongation and survivability may lead to genetic selection of more fertile cattle.
7. Clarifying which adaptive immune responses are impaired in fetuses persistently infected with flavivirus may lead to a better understanding of how immunotolerance is manifest.
8. Development of lentiviral-mediated methods to target the expression of individual genes within the ruminant placenta provides the opportunity to examine causeand- effect relationships during pregnancy.
9. Understanding the role of metabolic factors in regulating the synthesis and release of gonadotropins could help optimize management practices in ruminants to promote fertility.
10. Developing a method to infect specific hypothalamic neuronal populations with AAV, particularly in combination with improved identification of gonadotropes, will provide us with synergistic tools to better dissect the genetic and physiological mechanisms which underlie gonadotropin synthesis and release, and thus fertility.
11. This is the first large scale study in the Holstein population to test the slick gene mutation as a specific approach to increase thermotolerance. If proven successful, this finding can greatly benefit the dairy industry in areas affected by heat stress.
12. Poor maternal nutrition during gestation alters markers of oxidative stress in muscle and key growth factors in placental tissues.
13. Grazing different forages from 9 to 10.5 months of age did not affect reproductive development despite differences in rate of body weight gain.
14. Genome-wide association studies are a useful tool in determining the genetic potential of individual animals to express phenotypes that contribute to reproductive superiority.
15. Cows fed HIGH had improved glandular epithelial cells, greater SOD activity, and lower GPX activity than cows fed LOW indicating an improved redox environment in the uterine tissue, which may lead to improved post-partum fertility.
16. We are not sure what we have gained by this study. Field fertility may tell us something that we are unable to detect with flow cytometry, but it would have been encouraging to still see the improvements in flow cytometry measures of post that semen before field trials.
17. We observed heterogeneous blood vessel density within bovine placentomes while variation among placentomes within the same animal was minimal. This further validates our novel macroscopic imaging techniques of bovine placentomes.
18. Endogenous circadian oscillations of angiogenic factors and nutrient sensing genes were observed in bovine placentomes, suggesting the time of sampling can alter study results.
19. Increased preovulatory estradiol at GnRH-induced ovulation (day 0) and an increased change in estradiol concentration from day -2 (prostaglandin F2α-induced luteolysis) to day 0 improved pregnancy rate after embryo transfer. However, decreasing circulating postovulatory concentrations of progesterone by day 7 after GnRH-induced ovulation had no effect on pregnancy rate.  The mechanism by which preovulatory estradiol increases uterine receptivity to a transferred embryo is not clear at this time.
20. We have successfully characterized the release of FGF21 in beef heifers and cows.
21. We have determined that 4 pubertal classifications exist in our herd- Early, Typical, Start-Stop (SS) and Non-Cycling (NC). Those that are NC and SS have many of the characteristics of our High A4 population suggesting that they may become our High A4 cows. Interestingly they also appear to have increased inflammation and steroidogenesis which can be reduced by FSH stimulation in vivo. Thus we can identify this High A4 population early and may be able to develop beneficial therapies to enhance their ability overcome inflammation and allow for follicle progression and ovulation.
22. The SS pubertal classification appears to have both Start-Stop- Discontinuous (SSD) and Start-Stop-Start (SSS). The reproductive performance in the SSS appears to be more similar to typical heifers while the SSD is more like NC with reduced response to ProstaglandinF2alpha and reduced numbers of calves within the first 21 days of the calving season. Understanding how these females achieve puberty and how that affects their reproductive longevity is critical to determining if they should be maintained in the herd.
23. A combination of genotyping and sequencing data have identified six potential genetic variants in genes that are involved in oxidative stress or inflammation. Because we have also identified inflammation in both our High A4 cows and in NC and SS pubertal classifications we are interested in determining how these different genetic variants may be affecting ovarian function and female fertility and reproductive lifespan.
24. Lipids in the follicular fluid and blood plasma of High A4 cows indicate there is oxidative stress, inflammation in these cows. Excess lipids that activate signal transduction pathways may provide clues to how inflammation and oxidative stress may be contributing to female infertility.
25. Chemokine ligand 12 (CXCL12) signaling through its receptor, CXCR4, drives placental angiogenesis, but this axis is also important to cell survival and proliferation as well as inflammation, and may facilitate uterine receptivity. Using in vitro and in vivo experimental approaches, we demonstrated that CXCL12 can function as a mediator of localized inflammation at the fetal-maternal interface during implantation.
26. Because CXCL12-CXCR4 signaling encourages trophoblast viability and invasion, leukocyte migration, and inflammatory cytokine production, we hypothesized that intrauterine CXCL12-CXCR4 signaling governs local and systemic inflammatory potential during early gestation. Based on our studies of inhibiting CXCR4 at the fetal-maternal interface in vivo we suggest CXCL12-CXCR4 signaling may regulate endometrial cell viability important to placental development. Additionally, altering fetal-maternal CXCL12-CXCR4 signaling may represent a novel approach to modify local and systemic inflammation in the window when most pregnancy losses occur and impaired placental development transpires.
27. Altering the signaling of a central placental chemokine, CXCL12, by antagonizing its receptor CXCR4 at the fetal-maternal interface during initial placentation results in locally diminished vascularization, suppressed Akt/mTOR signaling, and induction of autophagy, all of which play vital roles for proper placentation. We propose the CXCL12-CXCR4 chemokine axis may govern placental homeostasis by serving as a critical upstream mediator of vascularization and cell viability and, if this signaling axis is compromised, impaired placental development transpires.
28. LPS modulates granulosa cell beta-catenin and aromatase transcription, both necessary components of estrogen production.
29. The subcellular localization during sperm maturation suggests the involvement of PRAMEY, especially the 13 kDa isoform, in sperm motility.
30. Telomere length was not dramatically different between age matched primiparious and multiparious cows due to the variation in telomere length measured using PLR procedures.
31. Tropically adapted cattle had much greater ruminal populations of fungi than temperate cattle. This may be one reason for the better performance of tropically adapted cattle on low quality forages.
32. The genetic marker TBX20-191081 was strongly related with temperament in Brahman cattle.
33. Poor maternal nutrition may alter offspring muscle development through genes involved in cell signaling, inflammation, and epigenetic regulation.
34. TRPM8 channels are putative testosterone receptors. Expressed number of channels may be dependent on the testosterone environment and may contribute to the reproductive soundness of the animal. These results indicated that the TRPM8 channels are sensitive to testosterone concentrations and may influence ram fertility.
35. Menthol is a known activator of the transient receptor potential melastatin subfamily 8 (TRPM8). Menthol is historically believed to have aphrodisiac properties. While past reports of TRPM8 in knockout mice suggested these channels may play a role in the expression of male behavior, oral application of a TRPM8 receptor agonist did not influence the expression of sexual interest.
36. Aflatoxin, specifically aflatoxin B₁ (AFB1), has negative effects on fertility in many species. Although aflatoxins decrease numbers of follicles in the female and sperm in the male reducing fertility rate, the mechanism has not been fully elucidated. Although treatment effects were not noted in the male teste, treatment with AFB1 influenced expression of TRPM8 in granulosa and theca cells of mice follicles. TRRM8 channels are evident in sheep ovaries and may suggest a similar influence of AFB1 in livestock species.

Activities

In the current reporting year, the members of the committee conducted or are continuing 73 projects.  A majority of these projects involve collaborations across research stations within W3112.

Arizona

1. Greater STAT-3 activity enhances mitochondrial respiration in the left ventricle of growth restricted fetuses.
2. Decreased Complex 1 Expression and Impaired Mitochondrial Function in Growth Restricted Ovine Fetuses with Placental Insufficiency
3. Generation of Tmem135 knockout mice.
4. Measurements of Mono-n-butyl Phthalate in the Tissues of Cycling Adult CD-1 Female Mice after the Oral Administration of Di-n-butyl Phthalate.
5. Effects of in vitro exposure to di-n-butyl phthalate and mono-n-butyl phthalate on early embryo viability and development
6. Effects of dibutyl phthalate (DBP) exposure on the expression of transcription factors in the mouse ovary
7. Environmentally Relevant Exposure to Dibutyl Phthalate and Ovarian Gene Expression: Effects of Terminal Estrous Cycle Stage
8. Environmentally Relevant Exposure to Dibutyl Phthalate Disrupts DNA Damage Repair Gene Expression in the Mouse Ovary
9. Effect of hypoxic stress on the fetal metabolome.

California

1. Effects of heat stress on preantral follicle development in vitro
2. Expression of the FSH receptor (FSHR) in bovine preantral follicles

Colorado

1. Development of bovine fluid tests to distinguish open from pregnant cows.
2. Embryo Mortality: A transcriptome perspective in Holstein cows.
3. Development of immunotolerance in bovine fetuses infected with BVDV.
4. Development of placental glucose transport deficient pregnancies.
5. Development of in vivo gene editing within the ruminant placenta.
6. Physiological Ramifications of Chorionic Somatomammotropin (CSH) Deficiency
7. Enrichment of ovine gonadotropes and characterization of gene expression.
8. Transcriptional response of ovine gonadotropes to estradiol.
9. Regulation of the estrogen-induced transcriptome by the peroxisome proliferatoractivated receptor alpha.
10. Ovine hypothalamus transduction by intracerebroventricular injection of adenoassociated virus.

Connecticut

1. The Effects of Maternal Nutrient Restriction Followed by Re-alimentation on Offspring Growth and Metabolism in Sheep
2. Effects of Restricted Maternal Nutrition and Re-alimentation on Fetal Muscle Development from Mid to Late Gestation in Sheep.
3. Poor maternal nutrition and gestational age affect oxidative stress in offspring muscle
4. Poor Maternal Nutrition During Gestation Alters Placental IGF-I, IGF-II, and IGFBP-3 mRNA Expression

Idaho

1. Effects of pre- and postweaning nutrition on fertility in beef heifers
2. Relationship between feed efficiency and fertility in beef heifers
3. Effect of nutrition during first two trimesters of gestation on fetal programming of reproduction in beef heifers.
4. Follicular development and response to estrous synchronization in heifers gestated and raised in two different environments
5. Genome-wide association studies of heifers with antral follicle count and reproductive tract score phenotypes

Illinois

1. Effects of fully-acidified, negative dietary cation-anion difference (DCAD) diets with differing concentrations of dietary calcium fed prepartum on the dominant follicle of the first follicular wave after parturition and pregnancy in Holstein cows
2. Effects of fully-acidified, negative dietary cation-anion difference (DCAD) diets with differing concentrations of dietary calcium fed prepartum on uterine morphology and redox environment of Holstein cows after parturition

Miles City - ARS

1. Effect of preovulatory estradiol or postovulatory progesterone on pregnancy rate in postpartum beef cows.
2. Evaluation of negative biomarkers of fertility and magnetic nano-purification as a tool to increase fertility with AI in beef bulls.

Mississippi

1. Investigating Placental Blood Vessel Density in Various Size Placentomes of Angus Cattle
2. Circadian Rhythms of Clock Genes and Angiogenic Factors in Bovine Placental Explants

Missouri

1. Effect of Preovulatory Estradiol and Postovulatory Progesterone on the Establishment of Pregnancy in Beef Cattle
2. Effect of preovulatory estradiol on subsequent luteal progesterone secretion in beef cows.

Montana State

1. Characterization of changes in temporal concentrations of fibroblast growth factor 21 (FGF21) in beef heifers and cows
2. Effects of nutrition on nutrient-sensing neuronal circuitry
3. The molecular basis of feed efficiency in range beef cattle.
4. In utero programming of the blood-brain barrier and nutrient-sensing circuitry that regulate reproductive function of beef cattle.

Nebraska

1. Follicle Stimulating Hormone Stimulation Restores Ovarian Microenvironment of Beef Heifers with Androgen Excess to Reduce Inflammation
2. Lipopolysaccharide Differentially Affects Pro-Inflammatory Responses in Theca Cells from Androgen Excess compared to Control Beef Cows
3. Genetic variants of an excess androgen ovarian microenvironment can be potential markers for a High A4 phenotype.
4. Early Reduced Growth Rates Predict Delayed or Altered Puberty and May Adversely Affect Reproductive Longevity in Beef Heifers
5. Altered Blood Plasma and Follicular Fluid Lipid Profiles Predict Alterations in Cell Signaling, Metabolism, and Immune Function in Cows with Androgen Excess
6. Effect of Medroxyprogesterone Acetate (a Progestin) on Spermatogenesis in Farmed Male Reindeer

New Mexico

1. Intrauterine infusion of AMD3100 in ewes: elucidating the importance of CXCL12 at the fetal-maternal interface
2. Intrauterine inhibition of chemokine receptor 4 signaling modulates local and systemic inflammation in ovine pregnancy
3. CXCR4 signaling at the ovine fetal-maternal interface regulates vascularization, CD34+ cell presence, and autophagy in the endometrium
4. Lipopolysaccharide modulation of granulosa cell steroid production.
5. Use and validation of ear tag accelerometers and RFID tags to determine parturition behavior in a pen setting.

Pennsylvania

1. PRAMEY protein dynamics in the bovine testis and epididymis.
2. Subcellular localization of PRAMEY during bovine sperm maturation.
3. Characterization of Sertoli and germ cells in the Prame conditional knockout (cKO) mice.
4. Single-cell transcriptome analysis of germ cells at postnatal day 7 from Prame cKO and floxed mice
5. Characterization of the Pramel1 cKO and gKO mice.
6. Genetic update of lost Holstein male lineages.

Texas

1. Prenatal transportation stress alters physiology of suckling Brahman bull calves as mediated by changes in DNA methylation.
2. Transgenerational influence of prenatal stress on temperament, birth weight, and weaning weight of Brahman calves.
3. Effect of prenatal transportation stress on DNA methylation in Brahman heifers
4. Genome-wide DNA methylation alteration in prenatally stressed Brahman heifer calves with the advancement of ages.
5. Identification of candidate genes related to temperament in Brahman cattle
6. Comparison of telomere length in age-matched primiparious and multiparious Brahman cows.
7. Influence of monensin in the diet of temperate and tropically adapted cattle on the ruminal and fecal metabolome and microbiome.

Utah

1. Comparing performance of gene set test methods
2. Effects of lactation and negative energy balance on endometrial expression
3. Epigenetic reprogramming, apoptosis, and developmental competence in cloned embryos
4. Increased statistical power from paired samples

Wyoming

1. Expression of TRPM8 mRNA in the prostate of rams and wethers
2. The effect of menthol on sexual behavior in rams
3. The effect of aflatoxin B1 treatment on expression of TRPM8 in mouse ovary and testes

Milestones

 W3112 has been successful in working with the Western Section of the American Society of Animal Science on developing symposia for the 2020 meeting of WSASAS.

Plans for the coming year

The members of the committee plan to conduct or complete over 50 studies.  The committee will use the outcomes from these studies and previous experiments conducted by this committee to begin to determine the direction for the committee in the future.  A writing committee will be appointed at the next annual meeting to begin preparing for project reauthorization.  The committee will also present a special symposium on sheep reproduction at the Western Section American Society of Animal Science meetings in June, 2020.