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The Veterinary Record Sep 2023There is limited information on the epidemiology of canine mammary tumours. This study aimed to estimate the incidence and risk factors for mammary tumours in UK bitches.
BACKGROUND
There is limited information on the epidemiology of canine mammary tumours. This study aimed to estimate the incidence and risk factors for mammary tumours in UK bitches.
METHODS
A nested case-control study was conducted within VetCompass to estimate the frequency and risk factors for clinically diagnosed mammary tumours during 2016 (VetCompass study). A second case-control study explored further breed associations for cases confirmed histopathologically compared to the VetCompass controls (laboratory study). Multivariable logistic regression was used to evaluate associations between risk factors and mammary tumours.
RESULTS
The incidence of mammary tumours was 1340.7/100,000 per year (95% confidence interval: 1198.1-1483.3). A total of 222 clinical cases (VetCompass study) and 915 laboratory cases (laboratory study) were compared to 1515 VetCompass controls in the two analyses. In the VetCompass study, Springer and Cocker Spaniels, Boxers, Staffordshire Bull Terriers and Lhasa Apsos had increased odds of developing mammary tumours. Neutering was associated with reduced odds, while odds increased with increasing age and a history of pseudopregnancy. In the laboratory study, increasing age was associated with greater odds of mammary tumours, and the breeds most at risk were similar to those identified in the VetCompass study.
LIMITATIONS
The timing of neutering was not consistently available. Comparing laboratory cases to VetCompass controls provided only exploratory evidence for the breed associations identified.
CONCLUSIONS
The study provides an update on the frequency of canine mammary tumours.
Topics: Female; Animals; Dogs; Case-Control Studies; Dog Diseases; Risk Factors; Mammary Neoplasms, Animal; United Kingdom
PubMed: 37231594
DOI: 10.1002/vetr.3054 -
Journal of Neuroendocrinology Jul 2023Sleep disruptions are a common occurrence during the peripartum period. While physical and environmental factors associated with pregnancy and newborn care account for...
Sleep disruptions are a common occurrence during the peripartum period. While physical and environmental factors associated with pregnancy and newborn care account for some sleep disruptions, there is evidence that peripartum fluctuations in estrogens may independently impact sleep. However, the impact of these large fluctuations in estrogens on peripartum sleep is unclear because it is difficult to tease apart the effects of estrogens on sleep from effects associated with the growth and development of the fetus or parental care. We therefore used a hormone-simulated pseudopregnancy (HSP) in female Syrian hamsters to test the hypothesis that pregnancy-like increases in estradiol decrease sleep in the absence of other factors. Adult female Syrian hamsters were ovariectomized and given daily hormone injections that simulate estradiol levels during early pregnancy, late pregnancy, and the postpartum period. Home cage video recordings were captured at seven timepoints and videos were analyzed for actigraphy. During "late pregnancy," total sleep time and sleep efficiency were decreased in hormone-treated animals during the white light period compared to pretest levels. Likewise, during "late pregnancy," locomotion was increased in the white light period for hormone-treated animals compared to pretest levels. These changes continued into the "postpartum period" for animals who continued to receive estradiol treatment, but not for animals who were withdrawn from estradiol. At the conclusion of the experiment, animals were euthanized and cFos expression was quantified in the ventral lateral preoptic area (VLPO) and lateral hypothalamus (LH). Animals who continued to receive high levels of estradiol during the "postpartum" period had significantly more cFos in the VLPO and LH than animals who were withdrawn from hormones or vehicle controls. Together, these data suggest that increased levels of estradiol during pregnancy are associated with sleep suppression, which may be mediated by increased activation of hypothalamic nuclei.
Topics: Cricetinae; Animals; Pregnancy; Female; Estradiol; Mesocricetus; Pseudopregnancy; Estrogens; Sleep
PubMed: 37127859
DOI: 10.1111/jne.13278 -
The Primary Care Companion For CNS... Apr 2023
Topics: Female; Pregnancy; Humans; Pseudopregnancy; Transgender Persons; Delusions; Transsexualism
PubMed: 37058715
DOI: 10.4088/PCC.22cr03343 -
Cells Mar 2023Multiple sclerosis (MS) is an autoimmune disease affecting the CNS and occurring far more prevalently in women than in men. In both MS and its animal models, sex...
Multiple sclerosis (MS) is an autoimmune disease affecting the CNS and occurring far more prevalently in women than in men. In both MS and its animal models, sex hormones play important immunomodulatory roles. We have previously shown that experimental autoimmune encephalomyelitis (EAE) affects the hypothalamic-pituitary-gonadal axis in rats of both sexes and induces an arrest in the estrous cycle in females. To investigate the gonadal status in female rats with EAE, we explored ovarian morphometric parameters, circulating and intraovarian sex steroid levels, and the expression of steroidogenic machinery components in the ovarian tissue. A prolonged state of diestrus was recorded during the peak of EAE, with maintenance of the corpora lutea, elevated intraovarian progesterone levels, and increased gene and protein expression of StAR, similar to the state of pseudopregnancy. The decrease in CYP17A1 protein expression was followed by a decrease in ovarian testosterone and estradiol levels. On the contrary, serum testosterone levels were slightly increased. With unchanged serum estradiol levels, these results point at extra-gonadal sites of sex steroid biosynthesis and catabolism as important regulators of their circulating levels. Our study suggests alterations in the function of the female reproductive system during central autoimmunity and highlights the bidirectional relationships between hormonal status and EAE.
Topics: Male; Rats; Female; Animals; Encephalomyelitis, Autoimmune, Experimental; Gonadal Steroid Hormones; Ovary; Multiple Sclerosis; Testosterone; Estradiol
PubMed: 37048118
DOI: 10.3390/cells12071045 -
Veterinary World Mar 2023The increase in the levels of the cortisol hormone caused by the stress conditions generated by an ovary transplantation procedure can damage the uterus of the...
Transplantation of Aceh cattle ovary into the uterus of pseudopregnant local rabbits: Effect of post-transplant stress on uterine histopathology and ovarian follicle dynamics.
BACKGROUND AND AIM
The increase in the levels of the cortisol hormone caused by the stress conditions generated by an ovary transplantation procedure can damage the uterus of the transplant recipient as well as the transplanted ovaries. This study aimed to analyze the histopathological changes that occur in the uterine horn of pseudopregnant local rabbits (recipients), as well as the ovarian follicular integrity of the donor Aceh cattle after transplantation.
MATERIALS AND METHODS
After 30 days of adaptation, all rabbits were divided into three treatment groups: R1 (the group of rabbits that underwent ovarian transplantation for 3 days, n = 5), R2 (the group of rabbits that underwent ovarian transplantation for 5 days, n = 5), and R3 (the group of rabbits that underwent ovarian transplantation for 7 days, n = 5). Pseudopregnancy induction was performed using the pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) methods. The rabbits were injected with 100 IU of PMSG intramuscularly, followed by an injection of 75 IU of hCG intravenously 3 days later. Ovarian transplantation was performed on day 8 (day 0 was the day of hCG injection). The concentration of cortisol hormone metabolites was measured from fecal samples using an enzyme-linked immunosorbent assay technique. The uterus and ovaries were collected for histopathological and follicular dynamics examination after the transplantation process was completed.
RESULTS
The mean cortisol levels (ng/g) recorded before versus after the transplant in the R1, R2, and R3 groups were 146.23 ± 17.60 versus 338.84 ± 302.79, 128.97 ± 81.56 versus 174.79 ± 101.70, and 124.88 ± 43.61 versus 321.91 ± 221.63 (p < 0.05), respectively. The examination of the histopathological appearance of the uterus revealed edema in the uterine lumen, hyperemia and hemorrhage in the endometrium, necrosis of the epithelium, and infiltration of inflammatory cells. Hemorrhage and hyperemia were severe and filled the endometrium in the R1 compared with the R2 and R3 animals. Ovarian follicle development occurred in all treatment groups, although some histopathological features were observed. The number of tertiary follicles in R1, R2, and R3 animals was 24.67 ± 7.37, 20.67 ± 7.57, and 9.67 ± 3.79 (p < 0.05), respectively.
CONCLUSION
Based on the results of this study, it can be concluded that the transplantation of ovaries from Aceh cattle into pseudopregnant local rabbits triggered an increase in the levels of the cortisol hormone and uterine histological changes; however, follicles were still detected at various stages of development in the transplanted Aceh cattle ovaries. The results of this study are valuable for clinicians and researchers because they provide information regarding an alternative ovarian preservation technique using pseudopregnant rabbits.
PubMed: 37041839
DOI: 10.14202/vetworld.2023.500-508 -
Toxicology May 2023Beta-cypermethrin (β-CYP) is a universally used pyrethroid pesticide with adverse effects on human health. β-CYP may impair endometrial remodeling in mice; however,...
Beta-cypermethrin (β-CYP) is a universally used pyrethroid pesticide with adverse effects on human health. β-CYP may impair endometrial remodeling in mice; however, the mechanism remains largely unknown. Endometrial remodeling plays a vital role in embryonic development and the maintenance of pregnancy. Therefore, we explored the mechanism by which peri-implantation β-CYP administration reduces uterine remodeling in pregnant mice. The C57BL/6 J pregnant mice were administered a dose of 20 mg/kg.bw. d β-CYP via oral gavage once daily from day 1 of gestation (GD1) to GD7. Molecular markers of endometrial remodeling, stromal cell proliferation, cell cycle regulation, and the PI3K/Akt/mTOR signaling pathway were evaluated in the decidual tissue of the uterus on GD7. An in vivo pseudopregnancy mouse model, a pregnant mouse model treated with an mTOR activator and an mTOR inhibitor and an in vitro decidualization model of mouse endometrial stromal cells were used to confirm β-CYP-induced defective endometrial remodeling and the key molecules expression of PI3K/Akt/mTOR signaling pathway. The results showed that β-CYP decreased the expression of the endometrial remodeling markers MMP9 and LIF in the uterine decidua. Peri-implantation β-CYP treatment markedly downregulated the expression of endometrial proliferation markers PCNA and Ki67 and decreased decidua thickness. Correspondingly, peri-implantation β-CYP exposure upregulated the expression of FOXO1, P57 and p-4E-BP1 in the decidua. Further experiments showed β-CYP significantly inhibited key molecules in the PI3K/Akt/mTOR pathway: PI3K, p-Akt/Akt, p-mTOR, and p-P70S6K in the uterine decidua. Additional experiments showed that aberrant endometrial remodeling induced by β-CYP was aggravated by rapamycin (an mTOR inhibitor) and partially reversed by MHY1485 (an mTOR agonist). In summary, our results indicated that a reduction in the PI3K/Akt/mTOR pathway may enhance defective endometrial remodeling by downregulating the proliferation and differentiation of endometrial stromal cells in early pregnant mice exposed to β-CYP. Our study elucidates the mechanism of defective endometrial remodeling induced by peri-implantation β-CYP exposure.
Topics: Pregnancy; Female; Mice; Humans; Animals; Decidua; Proto-Oncogene Proteins c-akt; Pesticides; Phosphatidylinositol 3-Kinases; Mice, Inbred C57BL; Endometrium; Embryo Implantation; TOR Serine-Threonine Kinases; Pyrethrins; Stromal Cells
PubMed: 37011868
DOI: 10.1016/j.tox.2023.153497 -
General and Comparative Endocrinology Jul 2023Polar bears (Ursus maritimus) in the wild are under threat due to climate change, primarily loss of sea ice, and experience poor reproductive success in zoos. The polar...
Polar bears (Ursus maritimus) in the wild are under threat due to climate change, primarily loss of sea ice, and experience poor reproductive success in zoos. The polar bear is a seasonally polyestrous species that exhibits embryonic diapause and pseudopregnancy, complicating characterization of reproductive function. Fecal excretion of testosterone and progesterone have been studied in polar bears, but accurately predicting reproductive success remains difficult. Dehydroepiandrosterone (DHEA) is a steroid hormone precursor correlated with reproductive success in other species, but has not been well studied in the polar bear. The purpose of the present study was to characterize the longitudinal excretion of DHEAS, the sulfated form of DHEA, from zoo-housed polar bears using a validated enzyme immunoassay. Lyophilized fecal samples from parturient females (n = 10), breeding non-parturient females (n = 11), a non-breeding adult female, a juvenile female, and a breeding adult male were investigated. Five of the breeding non-parturient females had been previously contracepted, while six were never contracepted. DHEAS concentrations were closely associated with testosterone concentrations (p < 0.05, rho > 0.57) for all reproductive statuses. Breeding females exhibited statistically significant (p < 0.05) increases in DHEAS concentration on or near breeding dates, which were not observed outside of the breeding season, or in the non-breeding or juvenile animals. Breeding non-parturient females exhibited higher median and baseline DHEAS concentrations than parturient females over the course of the breeding season. Previously contracepted (PC) breeding non-parturient females also exhibited higher season-long median and baseline DHEAS concentrations than non-previously (NPC) contracepted breeding non-parturient females. These findings suggest that DHEA is related to estrus or ovulation in the polar bear, that there is an optimal DHEA concentration window, and concentrations exceeding that threshold may be associated with reproductive dysfunction.
Topics: Animals; Female; Male; Ursidae; Dehydroepiandrosterone Sulfate; Reproduction; Testosterone; Estrus; Dehydroepiandrosterone
PubMed: 36940836
DOI: 10.1016/j.ygcen.2023.114276 -
Scientific Reports Mar 2023Embryo transfer (ET) is an essential reproductive technology for the production of new animal strains and maintenance of genetic resources. We developed a method, named...
Embryo transfer (ET) is an essential reproductive technology for the production of new animal strains and maintenance of genetic resources. We developed a method, named Easy-ET, to induce pseudopregnancy in female rats by artificial stimulation using sonic vibration instead of mating with vasectomized males. This study examined the application of this method for the induction of pseudopregnancy in mice. Offspring were obtained from two-cell embryos transferred into females with pseudopregnancy induced using sonic vibration in proestrus on the day before embryo transfer. Furthermore, high developmental rates of offspring were observed when pronuclear and two-cell embryos were transferred to females in estrus that were stimulated on the day of embryo transfer. Genome-edited mice were also obtained using frozen-warmed pronuclear embryos with clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated system (Cas) nucleases introduced using the technique for animal knockout system by electroporation (TAKE) method, which were transferred to females with pseudopregnancy induced on the day of embryo transfer. This study demonstrated that induction of pseudopregnancy by sonic vibration was also possible in mice.
Topics: Female; Male; Pregnancy; Mice; Rats; Animals; Pseudopregnancy; Vibration; Conversion Disorder; Delusions; Cell Communication
PubMed: 36869082
DOI: 10.1038/s41598-023-30774-x -
Frontiers in Veterinary Science 2023Reproduction causes major hormonal and physiological changes to the female body. However, the metabolic changes occurring during canine reproduction are scarcely studied.
INTRODUCTION
Reproduction causes major hormonal and physiological changes to the female body. However, the metabolic changes occurring during canine reproduction are scarcely studied.
METHODS
In this cross-sectional study, we assessed the metabolic effects of canine reproductive status using a H NMR metabolomics platform optimized and validated for canine use. The study population consisted of a total of 837 healthy, intact female dogs in breeding age, of which 663 dogs were in anestrus, 78 in heat, 43 were pseudopregnant, 15 were pregnant, and 38 were lactating. The differences in metabolite profiles between these states were studied by the Kruskal-Wallis test with tests performed using the Dunn's test, and visualized by box plots and a heatmap. The ability of the metabolite profile to differentiate pregnant dogs from non-pregnant ones was assessed by creating a multivariate Firth logistic regression model using forward stepwise selection.
RESULTS
Lactation, pregnancy and heat all were associated with distinct metabolic changes; pregnancy caused major changes in the concentrations of glycoprotein acetyls, albumin and creatinine, and smaller changes in several lipids, citrate, glutamine, and alanine. Pseudopregnancy, on the other hand, metabolically largely resembled anestrus. Lactation caused major changes in amino acid concentrations and smaller changes in several lipids, albumin, citrate, creatinine, and glycoprotein acetyls. Heat, referring to proestrus and estrus, affected cholesterol and LDL metabolism, and increased HDL particle size. Albumin and glycoprotein acetyls were the metabolites included in the final multivariate model for pregnancy detection, and could differentiate pregnant dogs from non-pregnant ones with excellent sensitivity and specificity.
DISCUSSION
These results increase our understanding of the metabolic consequences of canine reproduction, with the possibility of improving maternal health and ensuring reproductive success. The identified metabolites could be used for confirming canine pregnancy.
PubMed: 36816179
DOI: 10.3389/fvets.2023.1105113 -
Theriogenology Apr 2023Feline overpopulation raises issues concerning health, ecology, economy, and ethics. Procedures to limit overpopulation should carefully address animal welfare,...
Feline overpopulation raises issues concerning health, ecology, economy, and ethics. Procedures to limit overpopulation should carefully address animal welfare, efficiency, costs, and feasibility. Vasectomy in unowned cats is suggested as preferable to standard neutering as it maintains male sexual behaviour which may induce ovulation and pseudopregnancy in intact females and may prevent immigration of other males. Vasectomy is not performed routinely because it is fastidious, time consuming and requires more material than standard neutering. We describe epididymectomy as an alternative. In a first experiment, we analysed semen, testosterone, behaviour and pain in six experimental cats before and after epididymectomy, and after castration two months later. Excised tissues were analysed histologically. Testosterone concentrations did not differ significantly between intact and epididymectomised animals but were significantly different after castration. Sexual behaviour and testicular spermatogenesis persisted after epididymectomy, but with a marked drop in the semen count after 7 days. The Glasgow pain scores did not differ significantly after epididymectomy and castration. In a subsequent experiment, 20 privately owned cats were epididymectomised and castrated immediately afterwards, to analyse the learning curve and perioperative complications. The time required for an epididymectomy was significantly shorter than for castration. The study confirms that epididymectomy is quicker and less invasive than castration, it is associated with minimal risks and post-operative pain while easy to learn and inexpensive. Further field studies are required to test its efficiency for feline feral population control or in other species such as in bears, lions or deer, where infertility is required and castration not wanted.
Topics: Female; Animals; Cats; Male; Deer; Epididymis; Vas Deferens; Pain, Postoperative; Testosterone; Castration; Cat Diseases
PubMed: 36806926
DOI: 10.1016/j.theriogenology.2023.02.009