Description of a closed pyometra on a wild boar (Sus scrofa, Linnaeus 1758)

Pyometra is a pus accumulation in the uterine lumen. This paper reports an unusual case of pyometra in a female Sus scrofa of Parque Biologico de Gaia (Avintes, Portugal). The animal was of advanced age, and the clinical signs (e.g., anorexia, lethargy) were originally associated with geriatric conditions. The animal presented a large uterus, which likely further contributed to the locomotion difficulties and poor body condition. To the extent of our knowledge, this is the first report of a close pyometra in wild boar (Sus scrofa, Linnaeus, 1758). However, this diagnosis must be taken into account during uterine evaluation and special attention must be given to its inspection in meat animals.

A Study on the Transcriptional Profile of NOS2 and IFN-γ Genes in River Buffalo with Endometritis

Background and Aim: Uterine lumen contamination with bacteria is ubiquitous in buffalo after parturition. Nearly one-third of these infected animals develop endometritis which leads to reduced fertility. The present study aimed to evaluate the expressions of IFN-γ and NOS2 genes in uterine tissue of buffaloes with endometritis and comparing them with those in healthy animals using RT-qPCR Materials and Methods: Uterine samples were collected from 50 apparently healthy and 50 clinically infected buffaloes. RNA was extracted from the collected buffalo's uteri and cDNA was synthesized from extracted RNA. Quantitative Real Time PCR technique was performed using this synthesized cDNA. Results: Apparent up-regulation of both genes mRNA expression was recorded in endometritis-infected animals with 8.3-folds for IFN-γ and 9.99-folds for NOS2 (P<0.001). Conclusion: The upregulation of IFN-γ and NOS2 expression in the uterine tissue of endometritis-infected buffaloes can be used as a scale for measuring the efficiency of drugs used for endometritis treatment.

Insights into the lipidome and primary metabolome of the uterus from day 14 cyclic and pregnant sheep

In ruminants, conceptus elongation requires the endometrium and its secretions. The amino acid, carbohydrate, and protein composition of the uterine lumen during early pregnancy has been defined in sheep; however, a comprehensive understanding of metabolomic changes in the uterine lumen is lacking, particularly with respect to lipids. Here, the lipidome and primary metabolome of the uterine lumen, endometrium, and/or conceptus was determined on day 14 of the estrous cycle and pregnancy. Lipid droplets and select triglycerides were depleted in the endometrium of pregnant ewes. In contrast, select ceramides, diglycerides, and non-esterified fatty acids as well as several phospholipid classes (phosphatidylcholine, phosphatidylinositol, phosphatidylglycerols, and diacylglycerols) were elevated in the uterine lumen of pregnant ewes. Lipidomic analysis of the conceptus revealed that triglycerides are particularly abundant within the conceptus. Primary metabolite analyses found elevated amino acids, carbohydrates, and energy substrates, among others, in the uterine lumen of pregnant ewes. Collectively, this study supports the hypothesis that lipids are important components of the uterine lumen that govern conceptus elongation and growth during early pregnancy.

Histopathological findings in the uteri and ovaries of clinically healthy cats presented for routine spaying

Objectives The aim of this study was to assess the histopathological findings in the uteri and ovaries from clinically healthy queens presented for elective spaying. Methods Ovaries and distal uterine horns or complete uteri from 106 female cats were evaluated for pathological alterations. Results Pathological alterations of the uterus and/or ovaries were evident in 29 cats; of these, corpora lutea were present on the ovaries of 15 cats. Ovarian cysts were found in 15 cats and were classified as cysts of the Wolffian or Muellerian ducts (n = 4), follicular cysts (n = 4), luteal cysts (n = 1), cystic rete ovarii (n = 2), combinations of different cysts (n = 2) and non-classifiable cysts (n = 2). In 21/106 cats, cystic endometrial hyperplasia (CEH) was present. The incidence of CEH increased with the age of the cat. Six cats had purulent endometritis with or without distension of the uterine lumen. Hyperplastic lesions of the endometrium were detected in two cats. In one cat, a uterine horn malformation with duplication of one uterine horn lumen was diagnosed. Conclusions and relevance Whereas the majority of ovarian cysts and slight-to-moderate CEH are unlikely to interfere with an animal’s wellbeing, endometritis must be considered a serious health problem that requires veterinary attention.

410 Steroids Regulate SLC2A1 and SLC2A3 to Deliver Glucose into Trophectoderm for Metabolism via Glycolysis

The conceptuses (embryo/fetus and placental membranes) of pigs require energy to support elongation and implantation, and amounts of glucose and fructose increase in the uterine lumen during the peri-implantation period. Conceptuses from Day 16 of pregnancy were incubated with either 14C-glucose or 14C-fructose and amounts of radiolabeled CO2 released from the conceptuses measured to determine rates of oxidation of glucose and fructose. Both glucose and fructose transport into conceptuses, and glucose is preferentially metabolized in the presence of fructose, while fructose is actively metabolized in the absence of glucose and to a lesser extent in the presence of glucose. Endometrial and placental expression of glucose transporters SLC2A1, SLC2A2, SCL2A3 and SLC2A4 were determined. SLC2A1 mRNA and protein, and SLC2A4 mRNA were abundant in the uterine luminal epithelium of pregnant compared to cycling gilts, and increased in response to progesterone and conceptus-secreted estrogen. SLC2A2 mRNA was expressed weakly by conceptus trophectoderm on Day 15 of pregnancy, while SLC2A3 mRNA was abundant in trophectoderm/chorion throughout pregnancy. Therefore, glucose can be transported into the uterine lumen by SLC2A1, and then into conceptuses by SLC2A3. On Day 60 of gestation, the cell-specific expression of these transporters was more complex, suggesting that glucose and fructose transporters are precisely regulated in a spatial-temporal pattern along the uterine-placental interface of pigs to maximize hexose sugar transport to the pig conceptus/placenta.

Differential roles of uterine epithelial and stromal STAT3 coordinate uterine receptivity and embryo attachment

Although it has been reported that uterine signal transducer and activator of transcription 3 (STAT3) is essential for embryo implantation, the exact roles of uterine epithelial and stromal STAT3 on embryo implantation have not been elucidated. To address this issue, we generated Stat3-floxed/Ltf-iCre (Stat3-eKO), Stat3-floxed/Amhr2-Cre (Stat3-sKO), and Stat3-floxed/Pgr-Cre (Stat3-uKO) mice to delete Stat3 in uterine epithelium, uterine stroma, and whole uterine layers, respectively. We found that both epithelial and stromal STAT3 have critical roles in embryo attachment because all the Stat3-eKO and Stat3-sKO female mice were infertile due to implantation failure without any embryo attachment sites. Stat3-eKO uteri showed indented structure of uterine lumen, indicating the role of epithelial STAT3 in slit-like lumen formation in the peri-implantation uterus. Stat3-sKO uteri exhibited hyper-estrogenic responses and persistent cell proliferation of the epithelium in the peri-implantation uterus, suggesting the role of stromal STAT3 in uterine receptivity. In addition, Stat3-uKO female mice possessed not only the characteristic of persistent epithelial proliferation but also that of indented structure of uterine lumen. These findings indicate that epithelial STAT3 controls the formation of slit-like structure in uterine lumen and stromal STAT3 suppresses epithelial estrogenic responses and cell proliferation. Thus, epithelial and stromal STAT3 cooperatively controls uterine receptivity and embryo attachment through their different pathways.

Emerging Role of Extracellular Vesicles in Embryo–Maternal Communication throughout Implantation Processes

In ruminants, the establishment of proper conceptus–endometrial communication is essential for conceptus implantation and subsequent successful placentation. Accumulated evidence supports the idea that extracellular vesicles (EVs) present in uterine lumen are involved in conceptus–endometrial interactions during the preimplantation period. EVs make up a new field of intercellular communicators, which transport a variety of bioactive molecules, including soluble and membrane-bound proteins, lipids, DNA, and RNAs. EVs thus regulate gene expression and elicit biological effects including increased cell proliferation, migration, and adhesion in recipient cells. Uterine EVs are interactive and coordinate with ovarian progesterone (P4), trophectoderm-derived interferon tau (IFNT) and/or prostaglandins (PGs) in the physiological or pathological microenvironment. In this review, we will focus on intrauterine EVs in embryo–maternal interactions during the early stage of pregnancy, especially the implantation period in ruminant ungulates.

Steroids Regulate SLC2A1 and SLC2A3 to Deliver Glucose Into Trophectoderm for Metabolism via Glycolysis

The conceptuses (embryo/fetus and placental membranes) of pigs require energy to support elongation and implantation, and amounts of glucose and fructose increase in the uterine lumen during the peri-implantation period. Conceptuses from day 16 of pregnancy were incubated with either 14C-glucose or 14C-fructose and amounts of radiolabeled CO2 released from the conceptuses measured to determine rates of oxidation of glucose and fructose. Glucose and fructose both transport into conceptuses, and glucose is preferentially metabolized in the presence of fructose, whereas fructose is actively metabolized in the absence of glucose and to a lesser extent in the presence of glucose. Endometrial and placental expression of glucose transporters SLC2A1, SLC2A2, SCL2A3, and SLC2A4 were determined. SLC2A1 messenger RNA (mRNA) and protein, and SLC2A4 mRNA were abundant in the uterine luminal epithelium of pregnant compared to cycling gilts, and increased in response to progesterone and conceptus-secreted estrogen. SLC2A2 mRNA was expressed weakly by conceptus trophectoderm on day 15 of pregnancy, whereas SLC2A3 mRNA was abundant in trophectoderm/chorion throughout pregnancy. Therefore, glucose can be transported into the uterine lumen by SLC2A1, and then into conceptuses by SLC2A3. On day 60 of gestation, the cell-specific expression of these transporters was more complex, suggesting that glucose and fructose transporters are precisely regulated in a spatial-temporal pattern along the uterine-placental interface of pigs to maximize hexose sugar transport to the pig conceptus/placenta.