Sexual 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. Thus, the aim of this study was to investigate the effect of gestational maternal glyphosate exposure (50 mg/kg, NOAEL for reproductive toxicity) on the reproductive development of male offspring. Sixty-day-old male rat offspring were evaluated for sexual behavior and partner preference; serum testosterone concentrations, estradiol, FSH and LH; the mRNA and protein content of LH and FSH; sperm production and the morphology of the seminiferous epithelium; and the weight of the testes, epididymis and seminal vesicles. The growth, the weight and age at puberty of the animals were also recorded to evaluate the effect of the treatment. The most important findings were increases in sexual partner preference scores and the latency time to the first mount; testosterone and estradiol serum concentrations; the mRNA expression and protein content in the pituitary gland and the serum concentration of LH; sperm production and reserves; and the height of the germinal epithelium of seminiferous tubules. We also observed an early onset of puberty but no effect on the body growth in these animals. These results suggest that maternal exposure to glyphosate disturbed the masculinization process and promoted behavioral changes and histological and endocrine problems in reproductive parameters. These changes associated with the hypersecretion of androgens increased gonadal activity and sperm production.

Domestic cats (Felis catus) are widely believed to be highly sensitive to the effects of social stress, especially when living in high density populations. Cats are capable of adapting to living in a group, but this will often require opportunities for escaping and hiding. In this pilot study, adrenocortical activity, as a valuable physiological indicator of arousal underpinning potential emotional stress, was evaluated through the measurement of mean faecal glucocorticoid metabolites (mGCM) in fourteen singly and sixteen group-housed cats. Living conditions and ratings of the owners' quality of life (evaluated from self-reported questionnaires) were used as factors associated with faecal glucocorticoid levels of the cats. A direct association between the scores of owners' social dimension of quality of life and the cats' mGCM was found for single cats only, with higher owner social scores associated with higher cat mGCM. No significant differences in mGCM were found between singly versus group-living cats. This suggests that the under-explored factor of owner lifestyle could play an important role in domestic cats' day-today levels of arousal, especially when kept as single pets.

Progesterone (P4) plays a key role in pregnancy establishment and maintenance; during early pregnancy, P4 stimulates the production and release of uterine secretions necessary for conceptus growth prior to implantation; therefore, exogenous P4 supplementation may improve embryo development. This study evaluated the effects of supplementation during early pregnancy with long-acting injectable progesterone or altrenogest on embryonic characteristics of sows and gilts. Thus, a total of 32 sows and 16 gilts were used. On day 6 of pregnancy sows and gilts were allocated to one of the following groups: non-supplemented; supplemented with 20 mg of altrenogest, orally, from days 6 to 12 of pregnancy; supplemented with 2.15 mg/kg of long-acting injectable progesterone on day 6 of pregnancy. Animals were killed on day 28 of pregnancy, and ovulation rate, embryo survival, embryo weight, crown-to-rump length, uterine glandular epithelium and endometrial vascularization were assessed. Treatments had no effect on pregnancy rate, embryo survival or endometrial vascular density (P > 0.05). Non-supplemented gilts presented larger and heavier embryos compared to gilts from supplemented groups (P < 0.05). Sows in the altrenogest group presented larger and heavier embryos compared to non-supplemented sows and sows supplemented with long-acting injectable progesterone. In conclusion, supplementation of sows and gilts with progestagen from day 6 of pregnancy can be used as a means to improve embryo survival without deleterious effects.

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Our objectives were to investigate the possible role of VEGFA in bovine placenta steroid synthesis and to determine whether cloned derived placental cells present similar responses as non-cloned ones. Placental cells from cloned (term) and non-cloned (days 90, 150, 210 and term) pregnancies were isolated and treated with VEGFA (50 ng/ml) for 24, 48 or 96 h. Progesterone (P(4)) and estrone sulfate (E(1)S) were assessed by RIA, while aromatase P450-positive cells were quantified using the point counting test. The percentages of steroidogenic and non-steroidogenic populations were determined by flow cytometry. VEGFA augmented or decreased P(4) and E(1)S concentrations as well as aromatase P450-positive cell density, depending on gestational age and time in culture. The percentage of steroidogenic cells was lower than that of non-steroidogenic ones for each culture time (P < 0.05). VEGFA treatment did not change the proportion of steroidogenic and non-steroidogenic cells. Placental cells derived from cloned pregnancies presented higher concentrations of E(1)S and P4 than the non-cloned group. However, aromatase P450-positive cells were similar between groups (P > 0.05). VEGFA treatment altered P(4) and E(1)S levels in placental cells depending on type of gestation. These results suggest that VEGFA acts locally in the bovine placenta to modulate steroidogenesis during gestation, but in a different pattern between cloned and non-cloned derived placental cells at term. Therefore, this factor can be considered an important regulator of placental development and function.

The aim of this study was to evaluate hCG treatment on ovarian response and on pregnancy rate using a 9-day oestrus synchronization protocol in Santa Ines ewes. On a random oestrus cycle day, ewes received an intravaginal progesterone device (Primer-PR®, Tecnopec, Brazil). Nine days later (Day 9), 30µg of d-cloprostenol (Prolise®, Syntex, Argentina) and 250IU of eCG (Folligon®, Intervet, Brazil) were administered and the progesterone device was removed. This moment, the ewes were randomly assigned on two groups: Control Group and hCG Group. In the hCG Group, the ewes received 500IU of hCG (Vetecor®, Hertape-Calier, Spain) 24h after device removal. In the Control Group, the ewes did not receive any ovulation inductor. Control and hCG Groups ewes were inseminated 60h and 48h after device removal, respectively. There was no difference between the groups regarding the first ovulatory follicle diameter and the second ovulatory follicle. hCG Group ewes had shorter interval between device removal and ovulation (Control: 79.9±15.4h and hCG: 54.7±4.9h; P=0.001) and more synchronized ovulations. However, the treatment with hCG decreased the pregnancy rate after TAI (P=0,009). In conclusion, hCG administration improves ovulatory synchronisation, but causes a decrease in the pregnancy rate.

Serum hormone levels were compared between captive and free-living maned wolves and seasonal variations of sex hormones were studied. Blood samples were collected from 16 male and 26 female adult animals from Brazilian zoos, and from 30 male and 24 female free-living adults to determine serum progesterone and testosterone by radioimmunoassay. Serum testosterone concentrations varied (P < 0.05) across seasons for 16 captive males, being higher in autumn (2184.7 ± 355.1 pg/mL) than in summer (1080.7 ± 205.4 pg/mL), winter (1270.1 ± 276.6 pg/mL) and spring (963.9 ± 248.1 pg/mL), although they did not differ between summer, winter and spring. Testosterone concentration of 30 free-living males differed (P < 0.05) between autumn (824.1 ± 512.2 pg/mL), winter (14.4 ± 8.0 pg/mL) and spring (151.9 ± 90.5 pg/mL). Comparison between captive and free-living animals showed no difference in autumn (P > 0.05). Sixteen captive males showed higher testosterone concentration during winter and spring compared with 30 free-living animals (P < 0.05). Progesterone concentration varied among seasons in 26 captive females (P < 0.05), being higher in autumn (15.3 ± 3.1 ng/mL) than in summer (6.6 ± 1.5 ng/mL), winter (5.3 ± 3.1 ng/mL) and spring (4.3 ± 0.7 ng/mL). Progesterone concentration of 24 free-living females varied between autumn (17.1 ± 6.0 ng/mL) and winter (1.7 ± 0.3 ng/mL) (P < 0.05), but we could not obtain data for spring or summer. No difference in progesterone levels was observed between captive and free-living females in autumn and winter.

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