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1.
Anim Reprod ; 18(1): e20200431, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34122654

RESUMO

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). On day 6 of pregnancy, animals were allocated to one of the following groups: non-treated (NT, n = 6; 3 sows and 3 gilts), and (T, n = 6; 3 sows and 3 gilts) treated daily with 20 mg of altrenogest, from day 6-12 of pregnancy. All animals were euthanized on day 13 of pregnancy. All CLs were individually weighed, and their volume were determined. The endometrial glandular density (GD), mean glandular area (MGA), and vascular density (VD) were determined by histomorphometric and immunohistochemical analyses. Endometrium samples were collected and analyzed by qRT-PCR to evaluate the abundance of transcripts for VEGF and IGF-I. Females in the T group had higher MGA (P < 0.05) compared to the NT group. There was no effect of treatment on GD or VD for both experimental groups. Sows in the T group had augmented expression of IGF-I (P < 0.05). Progestagen had no detrimental effect on CL morphology. In conclusion, altrenogest improves the uterine environment during the peri-implantation period in pigs without compromising corpora lutea development.

2.
Conserv Physiol ; 8(1): coaa052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32577289

RESUMO

Habitat 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. In the present study, we assessed gonadal hormonal profiles of natural oestral cycles and puberty and compared our data to those of other wild felids. We collected faecal samples from two to seven times per week for 18 months from two adults and three pre-pubertal females. We defined baseline levels for progestins and oestrogens in order to estimate oestrous cycle length and age at puberty. We compared our data with 16 other species through generalized linear model, using weight and genus as two explanatory variables. Cycle length was 38.28 ± 2.52 days, ranging from 25 to 44 days, while sexual maturity was attained within 22 months. Due to our analysis of both hormonal and behavioural data, there is a variation between this research from other studies that employed only behavioural observations. Such difference may be caused by the absence of behavioural oestrous at the peri-pubertal period. When compared to wild felids of similar size, puberty and oestral cycle durations of the jaguar females fell within the same range. Our modelling showed that age at maturity was influenced mostly by size and only Leopardus partially explained the observed variation. Conversely, oestral cycle length did not differ among genera or size categories. Our study adds to the body literature in the reproductive endocrinology of wild felids, and because female gametes are more challenging to collect and preserve, a strong understanding on the female reproductive physiology is essential to assisted reproduction and wild population viability assessment.

3.
Anim Reprod Sci ; 155: 56-63, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25735830

RESUMO

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. Experiment 4 compared the pregnancy rate after the use of a DPR and Controlled Internal Drug Releasing Device (CIDR). The mean concentration of progesterone released by the DPR device during its first use (New Group: 5.1 ± 0.5 ng/ml) was greater than that during the second use (Re-used Group: 2.4 ± 0.3 ng/ml). There was no difference between the animals that received DPR devices for first and second use in terms of ovulatory follicle diameter, follicular wave emergence day for ovulatory follicle and period of ovulatory wave of ovarian follicular development. However, there was a significant difference between groups regarding the time between DPR device removal and first ovulation (New Group: 71.7 ± 2.5h and Re-Used Group: 63.9 ± 2.7h). Pregnancy rates were similar between ewes with DPR and CIDR devices. It was concluded that DPR is effective in increasing and maintaining progesterone concentrations, controlling follicular dynamics, promoting synchronized times of ovulation from healthy follicles, promoting development of a competent corpus luteum and when used results in pregnancy rates similar to that with use of the CIDR.


Assuntos
Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Progesterona/farmacologia , Ovinos/fisiologia , Administração Intravaginal , Animais , Sincronização do Estro/métodos , Feminino , Inseminação Artificial/veterinária , Folículo Ovariano/anatomia & histologia , Gravidez , Progesterona/administração & dosagem , Progesterona/sangue
4.
Pesqui. vet. bras ; 35(3): 304-310, 03/2015. tab, graf
Artigo em Português | LILACS | ID: lil-751976

RESUMO

A comunicação do estado reprodutivo nos primatas da família Callithrichidae, depende principalmente dos comportamentos sócio-sexuais como um sistema de sinalização primário, uma vez que nestas espécies a ovulação não é percebida pelos machos. Neste trabalho, os padrões de comportamentos sócio-sexuais foram analisados em conjunto com as concentrações de metabólitos fecais dos esteróides sexuais progesterona (MFP), estradiol (MFE) e testosterona (MFT) em casais cativos de Sagüi-de-tufos-pretos (Callithrix penicillata), nas diferentes fases do ciclo ovariano. O grupo estudado era composto por quarto casais adultos, mantidos no Centro de Reabilitação de Animais Selvagens da prefeitura de São Paulo. Os padrões comportamentais foram registrados pelo método de amostragem focal por intervalo de tempo a cada 30 segundos, cinco vezes por semana, totalizando 14.400 registros por animal. A mensuração das concentrações de metabólitos fecais dos esteroides sexuais foram realizados pelo método de enzima imunoensaio (EIE). Os resultados obtidos dessas concentrações possibilitaram a determinação endócrina das fases do ciclo ovariano (folicular e luteal) e de suas respectivas durações, assim como a determinação da fase periovulatória. Foram caracterizados 31 ciclos ovarianos completos, com duração de 24,3±4,1 dias (média ±DP), sendo que a fase folicular compreendeu 13,04±4,8dias e a fase lútea 11,2±4,2 dias. Os comportamentos sócio-sexuais (marcação por cheiro, cheirar genitália, catação e apresentação sexual) e a variável "proximidade" mostraram-se significativamente mais prevalentes na fase periovulatória do que nas demais fases do ciclo. Não houve alteração das concentrações de MFT dos machos ao longo de todo o período estudado. A análise conjunta das concentrações de metabólitos fecais de esteróides sexuais e dos comportamentos sócio-sexuais possibilitou um melhor entendimento das relações endócrino-comportamentais e reprodutivas de C. penicillata.


The communication of the female reproductive status in Callithrichidae relies mainly on the socio-sexual behavior, as generally the ovulation is concealed in this primate family by a primary signaling system. In this study the socio-sexual behavior patterns was analyzed in association with the concentration of fecal metabolites of sex steroid hormones progesterone (MFP), estradiol (MFE) and testosterone (MFT) in captive couples of Black-Tufted-Marmoset (Callithrix penicillata), during the different phases of the ovarian cycle. The studied group was composed of four adult couples kept in the São Paulo City Wild Animals Rehabilitation Center. The behavioral patterns were record by focal samplings, with 30 seconds intervals for each observation, five days a week, totalizing 14.400 registers per animal. The measurement of fecal metabolites of progesterone (MFP), estradiol (MFE) and testosterone (MFT) proceeded by enzyme immune assay (EIA). The results allowed to determine the duration of the ovarian cycle and to characterize three different phases (follicular, periovulatory and luteal). It was possible to determine 31 complete cycles that lasted 24.3±4.1 days (Mean ± SD). The follicular and luteal phases lasted 13.04±4.8 and the luteal phase 11.2±4.2 days. The behavioral patterns (scent marking, sniff genitals, grooming and sexual presentation) were more prevalent in the periovulatory phase as the behavioral variable "proximity" as well. There were no variations in the concentration of MFT in the males during the period studied. The associated analyses of the fecal metabolite of sex steroids and the socio-sexual behaviors led to a better understanding of the factors involved in the reproduction of C. penicillata.


Assuntos
Animais , Callithrix/fisiologia , Comportamento Sexual Animal/fisiologia , Hormônios Esteroides Gonadais/isolamento & purificação , Comportamento Social , Estradiol , Progesterona , Testosterona
5.
Reprod Fertil Dev ; 27(7): 1065-71, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24690451

RESUMO

The Amazonian manatee (Trichechus inunguis) is a threatened aquatic mammal endemic to the Amazon basin. The aim of this study was to evaluate the urinary and salivary reproductive hormone levels of captive Amazonian manatees collected during two seasons of the year. Salivary samples from four males and urinary and salivary samples from three females were collected during two seasons (March-June and September-November) over two consecutive years. Salivary testosterone in males was measured by radioimmunoassay and reproductive hormones in females (salivary progesterone and oestradiol and urinary progestogens, oestrogens and luteinising hormone) were measured by enzyme immunoassay. The data were analysed in a 2×2 factorial design, where the factors were year and season. There was no effect of year or season for salivary testosterone. All female hormones showed a seasonal effect (higher hormone levels during March-June than September-November) or an interaction between year and season (P<0.05). These results strongly indicate the existence of reproductive seasonality in Amazonian manatees; however, apparently only females exhibit reproductive quiescence during the non-breeding season. Further long-term studies are necessary to elucidate which environmental parameters are related to reproductive seasonality in T. inunguis and how this species responds physiologically to those stimuli.


Assuntos
Estradiol/análise , Hormônio Luteinizante/urina , Progesterona/análise , Estações do Ano , Testosterona/análise , Trichechus inunguis/metabolismo , Animais , Estradiol/urina , Feminino , Masculino , Progesterona/urina , Reprodução/fisiologia , Saliva/química , Testosterona/urina
6.
J Med Primatol ; 42(6): 325-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23909605

RESUMO

BACKGROUND: The studies on fecal steroid metabolites published with free-living primates are limited mainly by the difficulty in obtaining samples. METHODS: A radioimmunoassay was used to measure the fecal steroid concentrations in Alouatta belzebul in the National Forest of Tapirape-Aquiri in Brazil. RESULTS AND CONCLUSIONS: Androgens were significantly higher for the adult males from the Area of Influence (AI-I group) when compared to those from the Control Area (CA group) (P < 0.05). Progestin and estrogen concentrations were higher in the females from the CA group than in those from the AI-I for both the adult females and females with offspring; however, P < 0.05 was only observed in the concentrations of fecal progestins from the adult females. The physiological differences between the AI-I and CA groups suggest that the cause was a sum of factors, such as an exposure to sound waves, feeding habits, daily activity patterns, and the habituation of the animals.


Assuntos
Corticosteroides/análise , Alouatta , Fezes/química , Hormônios Esteroides Gonadais/análise , Animais , Brasil , Feminino , Masculino , Valores de Referência
7.
Arch Toxicol ; 86(4): 663-73, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22120950

RESUMO

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.


Assuntos
Glicina/análogos & derivados , Gonadotropinas Hipofisárias/metabolismo , Herbicidas/toxicidade , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Estradiol/sangue , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glicina/toxicidade , Hormônio Luteinizante/sangue , Masculino , Preferência de Acasalamento Animal/efeitos dos fármacos , Preferência de Acasalamento Animal/fisiologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , RNA Mensageiro/metabolismo , Ratos , Reprodução/fisiologia , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/patologia , Maturidade Sexual/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testosterona/sangue
8.
J Zoo Wildl Med ; 40(3): 458-65, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19746860

RESUMO

The 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. Two adult male manatees (A-1 and A-2) were submitted to an experimentation protocol of 12 day (D1 to D10). On D0, the animals received an intramuscular injection of gonadotropin-releasing hormone (GnRH)-analogue. Salivary, lacrimal, urinary, and fecal samples were collected daily (between 0800 hours and 0900 hours) and frozen at -20 degrees C until assayed. Fecal samples were lyophilized, extracted with 80% methanol, and diluted in buffer before the radioimmunoassay (RIA). Urine samples underwent acid hydrolysis and were diluted in depleted bovine serum. Salivary and lacrimal samples were assayed without the extraction step. Hormonal assays were conducted with a commercial testosterone RIA kit. An androgen peak (> median + 2 interquartile range [IQR]) was observed in all matrices of both animals, although it was less prominent in the lacrimal samples of A-2. However, the fecal androgen peak (A-1 peak = 293.78 ng/g dry feces, median [IQR] = 143.58 [32.38] ng/g dry feces; A-2 peak = 686.72 ng/g dry feces, median [IQR] = 243.82 [193.16] ng/g dry feces) occurred later than urinary (A-1 peak = 648.16 ng/mg creatinine [Cr], median [IQR] = 23.88 [30.44] ng/mg Cr; A-2 peak = 370.44 ng/mg Cr, median [IQR] = 113.87 [117.73] ng/mg Cr) and salivary (A-1 peak = 678.89 pg/ml, median [IQR] = 103.69 [119.86] pg/ml; A-2 peak = 733.71 pg/ml, median [IQR] = 262.92 [211.44] pg/ml) androgen peaks. These intervals appear to be correlated with the long digesta passage time in this species. The salivary and urinary peaks were closely associated. These results demonstrate that androgen concentrations in saliva, urine, or feces samples reflect reliably physiologic events and are a powerful tool for noninvasive reproductive monitoring of Amazonian manatees.


Assuntos
Androgênios/análise , Hormônio Liberador de Gonadotropina/farmacologia , Reprodução/fisiologia , Trichechus inunguis/metabolismo , Androgênios/sangue , Animais , Fezes/química , Aparelho Lacrimal/metabolismo , Masculino , Saliva/metabolismo , Urina/química
9.
Braz. j. vet. res. anim. sci ; 45(supl): 104-110, 2008.
Artigo em Português | LILACS | ID: lil-533246

RESUMO

Neste trabalho foi realizado estudo comparativo dos níveis de corticóides fecais (CF) de chimpanzé (Pan troglodytes) e orangotango(Pongo pygmaeus). Foram analisadas amostras coletadas em duas fases distintas, relacionadas com a introdução de técnicas de enriquecimento ambiental, a saber: Base (antes da introdução) e Habituação(imediatamente após). Realizamos as validações do conjunto comercial para radioimunoensaio ImmunuChem™ Double Antibody Corticosterone da MP Biomedicals, para mensuração de CF. A validação laboratorial dos conjuntos diagnósticos para uso em extrato fecal de primatas foi realizada pelo método de paralelismo, no qual, para cada espécie, concentrações conhecidas de corticosterona foram adicionadas a um pool de extratos fecais, sendo estas amostras analisadas em seguida. As inclinações das curvas obtidas nestes ensaios e da curva padrão do ensaio foram então comparadas. Os resultados obtidos para chimpanzé e orangotango, foram respectivamente, Y=17,23+1,31*X;R...


A comparative study of fecal corticoids (FC) concentrations was carried out with chimpanzees (Pan troglodytes) e orangutans (Pongo pygmaeus). Fecal samples were collected before (Basal) and just after (Habituation)enrichment introduction and analyzed. We performed biochemical and physiological validations of the ImmunuChem™ Double Antibody Corticosterone kit for radioimmunoassay from MP Biomedicals for quantifying FC concentrations. To establish the biochemical validity of our assay we performed parallelism assays in which pooled fecal extracts from both species were spiked with known quantities of corticosterone standard and the slopes of the curves obtained with these samples and the standard curves of the kits were compared. The correlation coefficients were R


Assuntos
Animais , Corticosteroides/análise , Fezes , Imunoensaio/métodos , Pan troglodytes , Pongo pygmaeus
10.
Braz. j. vet. res. anim. sci ; 42(4): 262-270, 2005. tab, graf
Artigo em Português | LILACS | ID: lil-433199

RESUMO

Foi estudada a atividade ovariana de fêmeas de onça-pintada (Panthera onca; adultas n=2 e pré-púberes n=3) mantidas em cativeiro, pela extração e quantificação de estrógenos e progestinas fecais. Foram colhidas amostras fecais de 2-7 vezes por semana durante 16-18 meses. Foi realizada a validação dos radioimunoensaios em fase sólida, para progesterona e 17beta-estradiol, para uso em extratos fecais em onça-pintada. A concentração média de estrógenos fecais (ng/g de fezes secas) para o grupo dos animais pré-púberes foi de 10,97 (variando de 0,28 a 59,16) e para o grupo dos animais adultos foi de 68,99 (variando de 3,50 a 609,37). A concentração média de progestinas fecais (müg/ g de fezes secas) para o grupo dos animais pré-púberes foi de 0,26 (variando de 0,02 a 4,44) e para o grupo dos animais adultos foi de 0,85 (variando de 0,08 a 6,51).


Assuntos
Animais , Feminino , Animais Selvagens , Carnívoros , Estrogênios/isolamento & purificação , Fezes , Progestinas/isolamento & purificação , Radioimunoensaio/métodos
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