Androgens and estrogens are steroid hormones that regulate reproductive processes in both males and females. Monitoring plasma levels of these steroids or their metabolites present in feces, offers diagnostic support for assessing the reproductive status of animals. Immunoassays are commonly used methods for quantifying these hormones, but their protocols require species-specific validation to ensure reliability.
View Article and Find Full Text PDFGlucocorticoids mediate physiological processes to obtain energy, presenting daily variation in basal levels that may be related to behavioural activity pattern. Identification of plasticity in the secretion of these hormones is essential to understand their effects on physiology and behaviour of wild birds and, therefore, their success in their natural or artificial environment. Serial endocrine evaluations are facilitated by implementing non-invasive methodologies that minimize possible effects of manipulation on the animal's physiological variables.
View Article and Find Full Text PDFAnim Reprod
May 2021
This study evaluated the effects of supplying altrenogest from day 6-12 of pregnancy on the endometrial glandular epithelium, corpora lutea (CL) morphology, and endometrial and CL gene expression. A total of 12 crossbred females (Landrace × Large White) were used. The females were assigned to 4 treatments according to a random design with a 2 × 2 factorial arrangement, with two categories (sow or gilt) and two treatments (non-treated and treated with altrenogest).
View Article and Find Full Text PDFHabitat loss and fragmentation have been leading jaguars to constant conflicts with humans, and as a result, jaguar populations have been declining over the last decades. Captive breeding is often a tool for species conservation, and it is not different for jaguars. However, success is far from optimal due to the lack of basic knowledge about species' reproductive biology.
View Article and Find Full Text PDFReproduction is key to species survival, and reproductive physiology represents a high priority investigative area for conservation biology, as it provides a basic understanding of critical life-history traits, information that is helpful for the establishment of management strategies. Here, we generated knowledge about the reproductive endocrinology of the hoary fox (), a small canid (2.5-4 kg) endemic to open areas of the Brazilian Cerrado and listed in the Brazilian National List of Endangered species.
View Article and Find Full Text PDFThyroid dysfunctions, such as hypothyroidism and hyperthyroidism, are the second most prevalent endocrinopathies and are associated to reproductive disorders in men. Several genes are differentially modulated by thyroid hormones in testes and imbalances in thyroid hormone levels are also associated to alterations on sperm functionality. Imbalances on antioxidant defense mechanism and stress oxidative have been pointed out as the main factors for the impairments on male reproductive function.
View Article and Find Full Text PDFIntroduction: The French surgeon Rene Jacques Croissant de Garengeot first described the finding of the Appendix inside a femoral hernia sac in 1731. The De Garengeot's hernia is a rare entity, comprehending only 0.5-5% of the femoral hernias.
View Article and Find Full Text PDFThe goal of this study was to optimize an ovulation induction protocol for use with artificial insemination in the southern tigrina (Leopardus guttulus). The specific aims were to report the efficacy of using altrenogest, an oral progestin (Regumate, MSD Animal Health, Merck Animal Health), to suppress ovarian activity and prevent follicular hyperstimulation and hyperestrogenism after the administration of exogenous eCG and hCG. To monitor ovarian responses, fecal estrogen and progestogen metabolites were quantified by enzyme immunoassay in females before and after intramuscular administration of 200-IU eCG and 150-IU hCG in two trials, 4 months apart.
View Article and Find Full Text PDFAnim Reprod Sci
April 2015
This study evaluated the effectiveness of a new progesterone intravaginal device (DPR) in ewes through four experiments: Experiment 1 compared the circulating progesterone concentration of ovariectomized ewes that received either a new or a re-used DPR. Experiment 2 compared the progesterone concentration between DPR-estrous-synchronized ewes and naturally estrous-cycling ewes. Experiment 3 evaluated the effect of new and re-used DPRs on ovarian follicular dynamics and time of ovulation of estrous cycling ewes.
View Article and Find Full Text PDFS-metolachlor is a chloroacetanilide herbicide widely used in the agriculture to control weeds and was demonstrated that it increases the activity of the aromatase enzyme in cell cultures, which may culminate as endocrine disruption action in vivo. To investigate this hypothesis, prepubertal Wistar male rats were exposed to metolachlor (5 or 50 mg/kg/day, NOEL for reproductive toxicity: 23.5-26.
View Article and Find Full Text PDFSexual differentiation in the brain takes place from late gestation to the early postnatal days. This is dependent on the conversion of circulating testosterone into estradiol by the enzyme aromatase. The glyphosate was shown to alter aromatase activity and decrease serum testosterone concentrations.
View Article and Find Full Text PDFThe Amazonian manatee (Trichechus inunguis) is endemic in the Amazonian basin and is the only exclusively fresh water sirenian. Historically hunted on a large scale, this species is now considered endangered, and studies on the reproductive physiology are critical for the improvement of reproductive management of captive and wild populations of manatees. The aim of this study was to verify the viability of androgen measurement in saliva, lacrimal, urine, and fecal samples of the Amazonian manatee by conducting a hormone challenge.
View Article and Find Full Text PDFSolanum lycocarpum, St. Hil (Solanaceae) is a common native shrub in the Brazilian cerrado. The fruits are used in folk medicine as a hypoglycaemic agent in the management of diabetes, obesity and to decrease cholesterol levels.
View Article and Find Full Text PDFTheriogenology
October 2006
One of the most frequent canine neoplasms is the transmissible venereal tumor (TVT), which affects the male and the female genital tract. The objective of this study was to determine (immunohistochemically) estrogen receptor (ER-alpha) expression in vaginal tissue of healthy bitches and in the vaginal and neoplastic tissues of TVT-affected bitches. Fifty-eight bitches were divided into two groups: tumor group (TVT) and control group (healthy).
View Article and Find Full Text PDFThe results of long-term administration of leuprolide acetate (LA) depot in a 52-yr-old Asian elephant bull (Elephas maximus) for control of musth are presented. Twelve injections were administered for 6 yr during our interpretation of early musth or "premusth." Intervals between musth periods during the study varied from 2 to 34 mo.
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