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1.
Reprod Domest Anim ; 59(7): e14660, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38962998

RESUMEN

The objectives of this experiment were to evaluate the effects of supplementation of Nellore (Bos indicus) cows with ß-carotene + vitamins A + D3 + E + biotin on body condition score (BCS), oestrus, pregnancy, and foetal morphometry. Lactating cows (n = 497) from two herds were balanced for BCS and calving period [early calving (EC); late calving (LC)] and were assigned randomly to: Control (n = 251)-supplementation with a mineral supplement; and SUP (n = 246)-supplementation with the mineral supplement fed to control + ß-carotene (150 mg/day) + vitamin A (40,000 IU/day) + vitamin D3 (5000 IU/day) + vitamin E (300 mg/day) + biotin (20 mg/day). Cows were supplemented from Days -30 to 30 (Day 0 = timed artificial insemination; TAI). Pregnancy was diagnosed 30 days after TAI and foetal crown-rump distance and thoracic diameter were measured at 30 and 77 days of gestation. Cows in the SUP treatment were more likely to have BCS ≥3.0 on Day 0 (63.0 ± 3.1 vs. 60.2 ± 3.1; p < .01) and were more likely to gain BCS from Days -30 to 30 (57.7 ± 3.3 vs. 44.1 ± 3.3%; p < .01). Fewer LC cows in the SUP treatment were detected in oestrus at the time of the first TAI (Control: LC: 75.4 ± 4.4 vs. SUP: LC: 64.0 ± 5.2 vs. Control: EC: 65.3 ± 4.0 vs. SUP: EC: 71.8 ± 3.7; p = .04). There was a tendency for the SUP treatment to increase pregnancy to the first TAI (64.2 ± 3.0 vs. 56.6 ± 3.1%; p = .08). A greater percentage of SUP cows was detected in oestrus at the time of the second TAI (70.1 ± 5.0 vs. 52.3 ± 4.8%; p = .01). The SUP treatment increased pregnancy to the second TAI among LC cows (SUP: LC: 75.9 ± 8.0% vs. Control: LC: 50.0 ± 8.3% vs. Control: EC: 52.0 ± 5.9% vs. SUP: EC: 41.4 ± 6.5%; p = .02). The SUP treatment increased foetal size (crown-rump; p = .04 and thoracic diameter; p < .01) at 30 days of gestation and, despite decreasing crow-rump length at 77 days after the first TAI among EC cows (p < .01), it increased the thoracic diameter at 77 days after the first TAI independent of calving season. Our results support that pregnancy establishment and foetal growth can be improved when grazing Nellore cows are supplemented with ß-carotene and vitamins A + D3 + E + biotin.


Asunto(s)
Biotina , Suplementos Dietéticos , Estro , Vitamina A , Vitamina E , beta Caroteno , Animales , Bovinos , Femenino , Embarazo , Vitamina A/administración & dosificación , Vitamina A/farmacología , beta Caroteno/administración & dosificación , beta Caroteno/farmacología , Vitamina E/administración & dosificación , Vitamina E/farmacología , Estro/efectos de los fármacos , Biotina/administración & dosificación , Biotina/farmacología , Colecalciferol/farmacología , Colecalciferol/administración & dosificación , Folículo Ovárico/efectos de los fármacos , Dieta/veterinaria , Vitaminas/administración & dosificación , Vitaminas/farmacología , Alimentación Animal , Lactancia , Feto/efectos de los fármacos
2.
Anim Reprod Sci ; 267: 107541, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38909485

RESUMEN

The objective of this study was to evaluate the impact of early progesterone removal on pregnancy rates to fixed-time artificial insemination (FTAI) in presynchronized beef cows. Postpartum beef cows (n = 882) were randomly assigned to 1 of 2 treatments: 1) 7&7 Synch: cows received a controlled internal drug release insert (CIDR) and a 25-mg injection of prostaglandin F2α on day 0, 100 µg of GnRH on day 7, a second injection of prostaglandin F2α (PG2) at CIDR removal on day 14, and a second injection of GnRH at FTAI 60-66 h after PG2 (day 17); 2) 7&6 Synch: cows received the same treatment as 7&7 Synch; however, CIDR removal occurred in conjunction with PG2 on day 13, while FTAI remained at 60-66 h after CIDR removal (day 16). Ovarian ultrasonography was performed to determine follicle diameter at PG2 and FTAI in a subset of cows (n = 40). Cows exposed to the 7&7 Synch tended to have larger follicle diameter at PG2 compared with 7&6 Synch cows (P = 0.09); however, there were no differences in follicle diameter at FTAI. No differences were determined between treatments for the expression of estrus (7&7 Synch: 61.6 ± 5.30; 7&6 Synch: 54.1 ± 5.45; P = 0.31) or pregnancy rates to FTAI (7&7 Synch: 60.8 ± 3.83; 7&6 Synch: 57.0 ± 3.84; P = 0.42). In conclusion, early removal of progesterone did not impact pregnancy rates in presynchronized beef cows.


Asunto(s)
Sincronización del Estro , Inseminación Artificial , Folículo Ovárico , Periodo Posparto , Índice de Embarazo , Progesterona , Animales , Femenino , Bovinos/fisiología , Embarazo , Progesterona/farmacología , Progesterona/administración & dosificación , Progesterona/sangre , Sincronización del Estro/efectos de los fármacos , Sincronización del Estro/métodos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Inseminación Artificial/veterinaria , Estro/efectos de los fármacos , Estro/fisiología , Dinoprost/farmacología , Dinoprost/administración & dosificación , Hormona Liberadora de Gonadotropina/farmacología , Hormona Liberadora de Gonadotropina/administración & dosificación
3.
Reprod Domest Anim ; 59(6): e14617, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38837282

RESUMEN

Sub-estrus buffaloes do not exhibit estrus signs despite being cyclic contributing to extended service periods and inter-calving intervals causing significant economic loss. The present study described the effect of synthetic prostaglandin (PGF2α) on estrus behaviour, follicular and luteal morphometry, and serum estradiol (E2) and progesterone (P4) profile in sub-estrus buffaloes during the non-breeding season. The incidence of sub-estrus was 38.4% during the non-breeding season. The sub-estrus buffaloes (n = 33) were divided into two groups, viz., Control (n = 16) and PGF2α treatment (Inj. Cloprostenol 500 µg, i.m., n = 17). Estrus induction response was significantly greater in the treatment (100 vs. 18.75%, p < .001), and a relatively greater proportion of animals conceived in the treatment group (29.41 vs. 6.25%, p = .08). The time elapsed to induction of estrus and insemination following treatment was significantly lower in the treatment group than control. A significant increment in the follicle diameter (9.72 ± 0.45 vs. 13.00 ± 0.45 mm, P < .0001) and serum estradiol (E2) concentration (66.01 ± 11.92 vs. 104.9 ± 13.21 pg/mL, p = .003) observed at the post-treatment period in the PGF2α treatment group. At the same time, CL diameter was reduced significantly at a higher regression rate in the PGF2α treated buffaloes than those of control. Of the responded buffaloes, only 30% showed high-intensity estrus attributed to the expulsion of cervico-vaginal mucus (CVM), uterine tonicity, micturition, and mounting response by a teaser bull. From this study, it can be concluded that the administration of PGF2α could induce estrus in the sub-estrus buffaloes during the non-breeding season. Behavioural changes, along with sonographic observation of POF, regressing CL, and serum E2 and P4 concentration would be useful to determine the right time of insemination in sub-estrus buffaloes during non-breeding season.


Asunto(s)
Búfalos , Dinoprost , Estradiol , Sincronización del Estro , Estro , Folículo Ovárico , Progesterona , Animales , Femenino , Búfalos/fisiología , Estradiol/farmacología , Estradiol/sangre , Progesterona/sangre , Progesterona/farmacología , Estro/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Dinoprost/farmacología , Dinoprost/administración & dosificación , Embarazo , Estaciones del Año , Cloprostenol/farmacología , Cloprostenol/administración & dosificación , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/fisiología , Inseminación Artificial/veterinaria , Conducta Sexual Animal/efectos de los fármacos
4.
Reprod Domest Anim ; 59(5): e14577, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38698696

RESUMEN

Sub-estrus is a condition when buffaloes do not display behavioural estrus signs, despite being in estrus and causes a delay in conception and increases the service period. The present study describes the effect of synthetic prostaglandin (PGF2α) alone and in combination with trace minerals on the follicular and corpus luteum (CL) dynamics, serum estradiol (E2) and progesterone (P4) concentration correlating estrus response and pregnancy outcome in sub-estrus buffaloes during the breeding season. A total of 50 sub-estrus buffaloes, identified through ultrasonography (USG) examination, were randomly allocated into three groups, viz. T1 (Synthetic PGF2α, Inj. Cloprostenol 500 µg, i.m, n = 17), T2 (Synthetic PGF2α + Trace mineral supplementation, Inj. Stimvet 1 mL/100 kg body weight, i.m., n = 17) and control (untreated; n = 16). Following treatment, 100% of sub-estrus buffaloes were induced estrus in the T1 and T2 groups, while only 18.75% were induced in the control. The CL diameter and serum P4 concentration were significantly lower at post-treatment, whereas the pre-ovulatory follicle (POF) size and serum E2 concentration were significantly higher in the T1 and T2 groups as compared to the control (p < .05). The buffaloes of the T2 group had a greater proportion of moderate intensities estrus than those of T1. Moreover, the proportion of buffaloes conceived in the T1 and T2 were 41.2% and 52.95%, respectively. The larger POF diameter and higher serum E2 concentration were associated with intense intensity estrus and higher conception rate (66.7%) in sub-estrus buffaloes. Similarly, CL regression rate, POF size and serum E2 concentration were relatively higher in the buffaloes conceived as compared to those not conceived. It is concluded that synthetic PGF2α in combination with trace minerals induces moderate to intense intensities estrus in a greater proportion of sub-estrus buffaloes and increases the conception rate during the breeding season. Moreover, behavioural estrus attributes correlating follicle and luteal morphometry, serum E2 and P4 concentration could be used to optimise the breeding time for augmenting the conception rate in sub-estrus buffaloes.


Asunto(s)
Búfalos , Cuerpo Lúteo , Dinoprost , Estradiol , Sincronización del Estro , Estro , Folículo Ovárico , Progesterona , Animales , Búfalos/fisiología , Femenino , Embarazo , Dinoprost/farmacología , Dinoprost/administración & dosificación , Progesterona/sangre , Progesterona/farmacología , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Estradiol/sangre , Estradiol/farmacología , Estradiol/administración & dosificación , Estro/efectos de los fármacos , Estro/fisiología , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/fisiología , Oligoelementos/farmacología , Oligoelementos/administración & dosificación , Cloprostenol/farmacología , Cloprostenol/administración & dosificación
5.
Theriogenology ; 224: 143-155, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38776702

RESUMEN

We aimed to evaluate the effects of administering estradiol (E-17ß) at the moment of timed-AI (TAI) on uterine gene expression, estrous expression rate (EER), and pregnancy rate (P/TAI) in Nelore cows with a small dominant follicle (DF) or not showing estrus at TAI. In Experiments 1 and 2 (Exp1, Exp2) cows were submitted to a P4/E-17ß-based protocol (day 0) for synchronization of ovulation. On day 7, devices were removed, cows received 1 mg E-17ß cypionate and 12.5 mg dinoprost. On day 9, cows with DF < 11.5 mm in diameter were split into different groups. In Exp1 (n = 16/group): Control (no treatment), E-2 (2 mg E-17ß) and E-4 (4 mg E-17ß). In Exp2: Control (n = 12); E-2 (n = 14); GnRH (0.1 mg gonadorelin acetate, n = 13); and E-2+GnRH (association of GnRH and E-17ß, n = 13). Between days 9 and 11, endometrial thickness (ET), time of ovulation detection, and EER were recorded. In Exp1, a uterine cytological sample was collected 4 h after treatment to evaluate the transcript expression of receptors for E-17ß (ESR1 and ESR2), oxytocin (OXTR), and P4 (PGR). In Experiment 3 (Exp3), 3829 suckled cows were submitted to a P4/E-17ß-based protocol for TAI. On day 9, devices were removed and cows received 1 mg E-17ß cypionate and 0.4 mg sodium cloprostenol. On day 11, TAI was performed and cows that did not demonstrate estrus received 0.1 mg gonadorelin acetate, and were allocated into two groups: GnRH (n = 368) and E-2+GnRH (2 mg E-17ß; n = 363). In Exp1, plasma E-17ß concentrations increased at 4 h after treatment in a dose-dependent manner but reduced at 12 h. The E-17ß-treated cows had greater transcript abundance for OXTR and lesser for ESR1 and ESR2, and the ET was reduced 12 h after treatment (P < 0.05). No significant difference (P > 0.1) was observed between the E-17ß doses in estrus or ovulation rate. In Exp2, the interval from treatment to ovulation was longer (P < 0.05) in the E-17ß group. GnRH-treated cows showed higher ovulation rates (89 vs. 35 %) compared to cows not treated with GnRH, as E-17ß-treated cows (P < 0.01) had a lower ovulation rate compared to those not receiving E-17ß (44 vs. 78 %). In Exp3, P/TAI was 55 % for cows in estrus. For those not showing estrus, no difference (P > 0.1) in P/TAI was observed between GnRH (34 %) and E-2+GnRH (31 %) groups. Cows with a DF ≥ 11 mm (n = 192) had a greater (P < 0.05) P/TAI (49 %) than those with DF < 11 mm (n = 377; 29 %). In conclusion, E-17ß administration in the moment of TAI modulates the mRNA expression of uterine receptors in cows with a small DF but does not impact the P/TAI compared with GnRH treatment in suckled Nelore not showing estrus previous to TAI.


Asunto(s)
Estradiol , Inseminación Artificial , Folículo Ovárico , Animales , Bovinos/fisiología , Femenino , Estradiol/farmacología , Estradiol/administración & dosificación , Estradiol/análogos & derivados , Embarazo , Inseminación Artificial/veterinaria , Folículo Ovárico/efectos de los fármacos , Sincronización del Estro/métodos , Sincronización del Estro/efectos de los fármacos , Estro/efectos de los fármacos , Útero/efectos de los fármacos , Índice de Embarazo
6.
Anim Reprod Sci ; 265: 107477, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663150

RESUMEN

The success of fixed - time artificial insemination (AI) in the ewe is variable due to poor synchrony of estrus. We examined the effects of long-term nutrition (LTN; low, medium, high - 6 months), short-term nutrition (STN; 1.0 M, 1.5 M - 14 days) and progesterone supplementation (P; single pessary, replacement on Day 9) on synchrony and reproductive outcomes. High LTN advanced (P < 0.05) estrus, increased (P = 0.06) pregnancy (range 71.1 - 81.1%) and improved (P < 0.01) litter size (range 1.30 - 1.50). STN increased (P < 0.05) pregnancy (79.0 versus 72.3%) but not litter size or timing of estrus. A LTN x STN interaction (P < 0.01) for time of estrus indicates that the effects of LTN were moderated by STN depending on the level of LTN. Pessary replacement delayed (P < 0.05) the onset of estrus, improved synchrony but did not affect pregnancy or litter size. High LTN increased (P < 0.05) the number of large (≥ 3.8 mm) and medium - size follicles (2.0 - 3.7 mm) but the diameter of large follicles tended to be reduced (P = 0.08) on Day 12. STN did not affect follicle number or size whilst P reduced (P < 0.05) the diameter of large follicles on Day 12 (4.83 versus 5.10 mm) and increased the number of medium - size follicles (3.56 versus 2.74 mm). In conclusion, both LTN and STN are major sources of variability in AI programs whilst pessary replacement has potential to reduce variability.


Asunto(s)
Suplementos Dietéticos , Inseminación Artificial , Progesterona , Animales , Femenino , Progesterona/administración & dosificación , Progesterona/farmacología , Inseminación Artificial/veterinaria , Inseminación Artificial/métodos , Embarazo , Ovinos/fisiología , Sincronización del Estro/métodos , Fenómenos Fisiológicos Nutricionales de los Animales , Alimentación Animal/análisis , Tamaño de la Camada/efectos de los fármacos , Dieta/veterinaria , Estro/efectos de los fármacos , Estro/fisiología , Factores de Tiempo
7.
Reprod Domest Anim ; 59(5): e14574, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38686570

RESUMEN

Cloprostenol, a synthetic derivative of prostaglandin F2α, effectively triggers functional and morphological regression of the corpus luteum (luteolysis). In rural Peru, the guinea pig (Cavia porcellus) holds significance within the local economy and serves as a valuable protein source. Enhancing reproductive efficiency is crucial to achieve uniformity in weight, age, and litter size across commercial systems. Thus, our study aimed to evaluate the effect of cloprostenol with and without male stimulation on the onset, duration, and intensity of oestrus in Peru guinea pigs. A total of 128 guinea pigs (120 females and eight males) between 8 and 12 months of age, weighing between 800 and 1200 g, were distributed in cages of 15 females per treatment. Cloprostenol sodium (0 [control], 0.20, 0.25, and 0.30 mg/animal) was IM administered to the groups with and without male stimulation. Four isolated males in individual cages, different from the one used for the treatment, were considered to detect oestrus. The oestrus intensity was assessed by observing sexual behaviour signs such as restlessness, moaning, attempts to mount, pelvic elevation, loin stretching, and vulvar inflammation. The oestrus was manifested 2 days after the administration of cloprostenol sodium. At a dose of 0.30 mg/animal and with male stimulation, the earliest oestrus was observed at 46.9 h. There was a reduction in the oestrus duration (p < .05) in guinea pigs that received the three doses of cloprostenol sodium compared to the control group. The highest percentages of frank oestrus intensity (66.7%) were strongly associated with the administered doses of cloprostenol sodium (p < .01). In conclusion, the cloprostenol sodium administration was proper for rapid oestrus induction in Peru guinea pigs.


Asunto(s)
Cloprostenol , Sincronización del Estro , Animales , Cobayas , Masculino , Femenino , Cloprostenol/farmacología , Cloprostenol/administración & dosificación , Sincronización del Estro/efectos de los fármacos , Conducta Sexual Animal/efectos de los fármacos , Estro/efectos de los fármacos , Perú
8.
Toxicol Appl Pharmacol ; 486: 116919, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38580201

RESUMEN

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a disease characterized by elevated intracranial pressure (ICP) and is a disease of young females. The first line pharmacological treatments include acetazolamide and topiramate and given the nature of IIH patients and the dosing regimen of these drugs, their effect on the endocrine system is important to evaluate. We aimed to assess the effects of acetazolamide and topiramate on steroid profiles in relevant endocrine tissues. METHODS: Female Sprague Dawley rats received chronic clinically equivalent doses of acetazolamide or topiramate by oral gavage and were sacrificed in estrus. Tissue specific steroid profiles of lateral ventricle CP, 4th ventricle CP, CSF, serum, uterine horn and fundus, ovaries, adrenal glands and pituitary glands were assessed by quantitative targeted LC-MS/MS. We determined luteinizing hormone (LH) and follicle stimulating hormones (FSH) levels in paired serum by ELISA. RESULTS: Topiramate increased the concentration of estradiol and decreased the concentration of DHEA in lateral choroid plexus. Moreover, it decreased the concentration of androstenediol in the pituitary gland. Topiramate increased serum LH. Acetazolamide decreased progesterone levels in serum and uterine fundus and increased corticosteroid levels in the adrenal glands. CONCLUSION: These results demonstrate that both acetazolamide and topiramate have endocrine disrupting effects in rats. Topiramate primarily targeted the choroid plexus and the pituitary gland while acetazolamide had broader systemic effects. Furthermore, topiramate predominantly targeted sex hormones, whereas acetazolamide widely affected all classes of hormones. A similar effect in humans has not yet been documented but these concerning findings warrants further investigations.


Asunto(s)
Acetazolamida , Disruptores Endocrinos , Estro , Ratas Sprague-Dawley , Topiramato , Animales , Femenino , Topiramato/farmacología , Acetazolamida/farmacología , Acetazolamida/toxicidad , Disruptores Endocrinos/toxicidad , Ratas , Estro/efectos de los fármacos , Hormona Luteinizante/sangre , Fructosa/toxicidad , Fructosa/análogos & derivados , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Progesterona/sangre , Hormona Folículo Estimulante/sangre , Hormonas Esteroides Gonadales/sangre , Estradiol/sangre , Ovario/efectos de los fármacos , Ovario/metabolismo
9.
Endocrinology ; 163(3)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35134138

RESUMEN

Female mice homozygous for an engineered Gnrhr E90K mutation have reduced gonadotropin-releasing hormone signaling, leading to infertility. Their ovaries have numerous antral follicles but no corpora lutea, indicating a block to ovulation. These mutants have high levels of circulating estradiol and low progesterone, indicating a state of persistent estrus. This mouse model provided a unique opportunity to examine the lack of cyclic levels of ovarian hormones on uterine gland biology. Although uterine gland development appeared similar to controls during prepubertal development, it was compromised during adolescence in the mutants. By age 20 weeks, uterine gland development was comparable to controls, but pathologies, including cribriform glandular structures, were observed. Induction of ovulations by periodic human chorionic gonadotropin treatment did not rescue postpubertal uterine gland development. Interestingly, progesterone receptor knockout mice, which lack progesterone signaling, also have defects in postpubertal uterine gland development. However, progesterone treatment did not rescue postpubertal uterine gland development. These studies indicate that chronically elevated levels of estradiol with low progesterone and therefore an absence of cyclic ovarian hormone secretion disrupts postpubertal uterine gland development and homeostasis.


Asunto(s)
Estradiol/sangre , Estro/fisiología , Infertilidad Femenina/genética , Progesterona/sangre , Receptores LHRH/genética , Útero/crecimiento & desarrollo , Animales , Gonadotropina Coriónica/farmacología , Estro/efectos de los fármacos , Femenino , Infertilidad Femenina/sangre , Ratones , Ratones Noqueados , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Progesterona/farmacología , Útero/efectos de los fármacos
10.
Fitoterapia ; 157: 105108, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34954263

RESUMEN

This research aimed to investigate the estrogen-like effects of Leonurine hydrochloride (Leo). First, we developed a total synthesis of Leo from 3,4,5-trimethoxy-benzoic acid and the structure was confirmed through 1H NMR and mass spectrometry (MS). Then the estrogenic activity of Leo in vitro and in vivo was studied. The proliferation and proliferation inhibitory effects of Leo on MCF-7 cells and MDA-MB-231 cells indicate that Leo exerts estrogen-like effects through estrogen receptor α (ERα) and estrogen receptor ß((ERß) in vitro. Uterotrophic assay in juvenile mice showed that Leo has an estrogen-like effect in vivo, as it can promote the development of the uterus of juvenile mice, increase its uterine coefficient and the size of the uterine cavity, as well as the increased number of uterine glands and the thickened uterine wall. For further research, cyclophosphamide (CTX) was used to establish a mouse model of ovarian function decline. Through this model, we found that Leo can restore the estrous cycle of mice, increase the number of primordial and primary follicles in the ovaries of mice, and regulate the disordered hypothalamic-pituitary-ovarian (HPOA) axis of mice. Finally, the pharmacokinetics of Leo was studied and oral bioavailability of Leo was calculated to be 2.21%. Leo was synthesized and the estrogen-like effect in vitro and in vivo was confirmed as well as its pharmacokinetics.


Asunto(s)
Ácido Gálico , Menopausia , Animales , Femenino , Humanos , Masculino , Ratones , Ratas , Disponibilidad Biológica , Western Blotting , Peso Corporal/efectos de los fármacos , Estro/efectos de los fármacos , Ácido Gálico/análogos & derivados , Ácido Gálico/síntesis química , Ácido Gálico/metabolismo , Ácido Gálico/farmacocinética , Ácido Gálico/farmacología , Ácido Gálico/uso terapéutico , Hidroxibenzoatos/síntesis química , Menopausia/efectos de los fármacos , Ratones Endogámicos ICR , Ovario/patología , Distribución Aleatoria , Sincalida/análisis , Útero/patología , Vagina/citología
11.
Bioengineered ; 12(1): 7215-7223, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34546841

RESUMEN

Soy isoflavones have been widely used in the treatment of clinical gynecological diseases. The aim of this study was to investigate the therapeutic effect and molecular mechanism of Soy isoflavones on rats with polycystic ovary syndrome (PCOS). Sprague-Dawley rats were orally administered 1 mg/kg letrozole for 21 consecutive days to induce the PCOS rat model. After PCOS induction, Soy isoflavones (100 mg/kg) or metformin (Positive control; 500 mg/kg) was administered continuously for 28 days. Then, H&E staining was used to observe the pathological changes of ovary. The serum hormone levels and the levels of antioxidant and inflammatory cytokines in ovarian tissue were detected. Additionally, the expression of NF-κB signaling pathway protein was detected by Western blot. Our results showed that soy isoflavones treatment significantly reduced the body weight, ovarian volume and weight, and improved estrous cycle in PCOS rats. H&E staining showed that the number of cystic dilated follicles and atretic follicles in ovarian tissue diminished, showing healthy follicles and corpus luteum. In addition, soy isoflavones treatment markedly decreased serum testosterone and luteinizing hormone (LH) levels, as well as oxidative stress levels and inflammation levels, and increased estradiol (E2) and follicle stimulating hormone (FSH) levels. At the same time, Soy isoflavones treatment inhibit the phosphorylation level of NF-κB p65 and increased the IκBα expression in ovarian tissues of PCOS rats. Overall, Soy isoflavones can improve ovarian morphology and hormone disorders in PCOS rats by inhibiting the activity of NF-κB pathway and enhancing anti-inflammatory and antioxidant capacity.


Asunto(s)
Glycine max/química , Isoflavonas/farmacología , FN-kappa B/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Estro/efectos de los fármacos , Femenino , Letrozol/efectos adversos , Ovario/efectos de los fármacos , Síndrome del Ovario Poliquístico/inducido químicamente , Ratas , Ratas Sprague-Dawley
12.
Reprod Domest Anim ; 56(11): 1398-1405, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34388283

RESUMEN

As dogs experience oestrus only once or twice a year, it is necessary to establish an effective method of oestrous induction for efficient breeding. In the present study, we evaluated inhibin antiserum (IAS) on oestrous induction in anoestrous females. Bitches were administered 0.5 ml/kg IAS or a mixture of 50 IU/kg equine chorionic gonadotropin (eCG) and 0.5 ml/kg IAS and 500 IU human chorionic gonadotropin (hCG) administered 7 days after the mixture injection. As a control, bitches received 50 IU/kg eCG, with 500 IU hCG administered 7 days after eCG injection. Blood-tinged vaginal discharge, vulvar swelling, plasma progesterone concentrations and ovarian follicular development were assessed from day 0 to day 14. IAS alone injection did not induce oestrus in bitches at the anoestrous stage. Conversely, vulvar swelling, blood-tinged vaginal discharge and an estimated luteinizing hormone (LH) surge appeared on days 3-7, days 3-6 and days 7-9 after the IAS+eCG mixture injection, respectively, in all five bitches at the anoestrous stage. The average number of developing and ovulated follicles in bitches administered IAS+eCG was 8.8 and 9.6 respectively. A single eCG injection followed by hCG induced oestrous signs, with an average of 8.3 developing follicles and 4.5 ovulated follicles. This study revealed that IAS alone did not induce oestrus, but when IAS was used in combination with eCG, it induced oestrus and promoted a considerable number of ovulations in anoestrous dogs.


Asunto(s)
Gonadotropinas Equinas/farmacología , Sueros Inmunes/administración & dosificación , Inhibinas/inmunología , Inducción de la Ovulación/veterinaria , Animales , Gonadotropina Coriónica/farmacología , Perros , Estro/efectos de los fármacos , Femenino , Inducción de la Ovulación/métodos
13.
Reprod Domest Anim ; 56(11): 1369-1376, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34370879

RESUMEN

Based on different surveys, dairy farmers are concerned about extensive use of exogenous oxytocin in buffaloes, which is being held responsible for reproductive problems including irregular oestrous cycle and delayed ovulation. For these concerns, effects of oxytocin injection on postpartum follicular dynamics, postpartum oestrous interval (PEI), oestrous length, the interval from onset of estrus to ovulation and blood progesterone (P4) were studied in Nili-Ravi buffaloes. For this purpose, 23 animals within 1 week after calving were randomly divided into three groups: without oxytocin (CON; n = 7), 10 i.u. oxytocin (LOW; n = 8), 30 i.u. oxytocin - (HIGH; n = 8) and used to record the PEI for the study period of 154 days. At subsequent estrus, three buffaloes from each group (not served) were selected randomly to monitor two cycles for 6 weeks. Transrectal ultrasonography was performed to evaluate follicular and corpus luteum (CL) development, and blood sampling was done for progesterone (P4) analysis. These results revealed that postpartum oestrous interval (PEI) decreased significantly in oxytocin-treated groups. The number of small, medium and total follicles on the left ovary was significantly higher in the HIGH group. However, an overall number of small and total follicles on both right and left ovaries was significantly higher in CON and HIGH groups. On the other hand, there was no difference in the number of follicles on the right ovary among all treatment groups. The same was true for the size of pre-ovulatory follicles, CL, P4 concentrations and oestrous cycle length. The intervals from onset of estrus to ovulation and from standing estrus to ovulation were increased considerably in the HIGH group. It is concluded that exogenous oxytocin administration resulted in the shortening of PEI but triggered a delay in ovulation. Moreover, a higher dose of oxytocin could stimulate the growth of small, medium, and total follicles in postpartum Nili-Ravi buffaloes.


Asunto(s)
Estro/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Oxitocina/farmacología , Animales , Búfalos , Industria Lechera/métodos , Femenino , Ovario/diagnóstico por imagen , Oxitocina/administración & dosificación , Periodo Posparto/fisiología , Progesterona/sangre
14.
Reprod Toxicol ; 104: 8-15, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34182086

RESUMEN

Malathion is a high-efficiency organic phosphorus broad-spectrum insecticide which is commonly used in agricultural production, sanitation and epidemic prevention. Although the toxic effects of malathion on animal reproduction have been partially evaluated, its function, regulatory mechanism and antidote in estrus cycle and reproductive damage remain generally unclear. Here, the results showed that malathion disrupted the normal estrus cycle in mice, reduced the secretion of ovarian hormones, increased the amount of reactive oxygen species (ROS), and promoted autophagy and apoptosis in the ovary. Interestingly, we found that an antioxidant resveratrol could inhibit the disorders of estrus cycle and steroid hormone synthesis, reduced the abnormality of ROS accumulation, autophagy and apoptosis in malathion-exposed ovarian tissue. Furthermore, compared with those of the control group, malathion induced autophagy and apoptosis in the granular cells, whereas resveratrol attenuated these effects of malathion. Therefore, disadvantages of malathion exposure on estrus cycle disorder could partly reverse by resveratrol supplement. Overall, resveratrol may be a potential drug to prevent malathion-induced ovarian damages and estrus cycle disorder. Our findings provide new insights into ovarian response to malathion and resveratrol exposure.


Asunto(s)
Insecticidas/toxicidad , Malatión/toxicidad , Sustancias Protectoras/farmacología , Resveratrol/farmacología , Animales , Antioxidantes , Apoptosis , Autofagia , Estro/efectos de los fármacos , Femenino , Ratones , Ovario , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno
15.
Anim Reprod Sci ; 230: 106769, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34090093

RESUMEN

This study was conducted to determine whether exogenous melatonin affected gilt fertility when there were different housing temperature and lighting conditions. Prepubertal gilts (n = 72) were fed (MEL, 5 mg/day) or not fed (CON) melatonin while housed in rooms where temperatures (31.0 ± 1 °C) and daily lighting (240 lx) duration differed: 8 (8 H); 16 (16 H); or 24 (24 H) h in winter and summer replicates. Gilts were moved into rooms (day 1) and administered PG600 on day 6. Gilts detected in estrus were inseminated and slaughtered on day 33 of gestation to determine pregnancy and litter responses. There was no treatment x room effect on estrus (77.8 %), follicle sizes, or number of corpora lutea, but MEL-treated gilts had a longer (P = 0.02) estrous duration (2.0 d) than gilts of the CON (1.7 d) group. Pregnancy rate (92.6 %) and embryo number (13.5) were not affected by treatment or room conditions. There was a treatment x room effect, however, with embryo survival being less (P = 0.01) by ∼23 % in gilts of the CON-24H than CON-16H, MEL-8H, and MEL-24H groups. In the summer replicate, there were also fewer large follicles, a lesser estrous detection percentage, viable embryos, and embryo survival rate than during the winter (P < 0.05). Overall, MEL treatment had positive effects on estrous duration and embryo survival, especially in the summer when there were varying lighting regimens and room temperatures in which gilts were housed.


Asunto(s)
Cuerpo Lúteo/fisiología , Vivienda para Animales , Melatonina/farmacología , Folículo Ovárico/fisiología , Porcinos/fisiología , Temperatura , Animales , Antioxidantes/farmacología , Estro/efectos de los fármacos , Femenino , Respuesta al Choque Térmico/efectos de los fármacos , Fotoperiodo , Estaciones del Año
16.
Anim Reprod Sci ; 228: 106751, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33866258

RESUMEN

Effects were evaluated in Bos indicus cows of eCG and FSH on follicular growth, estrous expression, and pregnancy per artificial insemination (P/AI) as a result of fixed-time artificial insemination (TAI). In Experiment 1, extent of timing-of-ovulation synchronization among cows was evaluated after imposing an estrogen/progesterone-based treatment regimen. At progesterone device removal (D8), cows were administered: eCG, or FSH or served as untreated Controls. In Experiment 2, percentage of cows P/AI was evaluated when the Experiment 1-treatment regimen was imposed. On D10, all cows were artificially inseminated. In Experiment 3, cows were assigned to two treatment groups (Control and eCG) on D8 to evaluate percentage of cows P/AI and estrous expression. In Experiment 1, follicular dynamics were similar among treatment groups. In Experiment 2, follicular growth was greater (P = 0.0001) with the eCG treatment. There was an interaction of treatment × parity (P = 0.007) on percentage of cows P/AI. There was a greater percentage of primiparous cows P/AI in the eCG-treated than Control and FSH-treated cows. There was a greater percentage of eCG-treated multiparous cows pregnant as a result of TAI than Control cows. There was an interaction of treatment × parity (P = 0.005) on P/AI in Experiment 3, in which the eCG effect was more pronounced in primiparous cows. Treatment with FSH, therefore, was not as effective as eCG in stimulation of follicular growth or enhancing percentage of cows pregnant as a result of TAI. Physiological effects of eCG, however, were also more evident in primiparous cows.


Asunto(s)
Bovinos , Gonadotropina Coriónica/farmacología , Estradiol/análogos & derivados , Estro/efectos de los fármacos , Hormona Folículo Estimulante/farmacología , Inseminación Artificial/veterinaria , Animales , Gonadotropina Coriónica/administración & dosificación , Esquema de Medicación , Estradiol/administración & dosificación , Estradiol/farmacología , Femenino , Hormona Folículo Estimulante/administración & dosificación , Inseminación Artificial/métodos , Paridad , Embarazo , Índice de Embarazo
17.
Reprod Biol Endocrinol ; 19(1): 47, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33752672

RESUMEN

BACKGROUND: Long-acting, reversible contraceptives (LARC; progestin only) are an increasingly common hormonal contraceptive choice in reproductive aged women looking to suppress ovarian function and menstrual cyclicity. The overall objective was to develop and validate a rodent model of implanted etonogestrel (ENG) LARC, at body size equivalent doses to the average dose received by women during each of the first 3 years of ENG subdermal rod LARC use. METHODS: Intact, virgin, female Sprague-Dawley rats (16-wk-old) were randomized to 1 of 4 groups (n = 8/group) of ENG LARC (high-0.30µg/d, medium-0.17µg/d, low-0.09µg/d, placebo-0.00µg/d) via a slow-release pellet implanted subcutaneously. Animals were monitored for 21 days before and 29 days following pellet implantation using vaginal smears, ultrasound biomicroscopy (UBM), saphenous blood draws, food consumption, and body weights. Data were analyzed by chi-square, non-parametric, univariate, and repeated measures 2-way ANOVA. RESULTS: Prior to pellet implantation there was no difference in time spent in estrus cycle phases among the treatment groups (p > 0.30). Following pellet implantation there was a dose-dependent impact on the time spent in diestrus and estrus (p < 0.05), with the high dose group spending more days in diestrus and fewer days in estrus. Prior to pellet insertion there was not an association between treatment group and estrus cycle classification (p = 0.57) but following pellet implantation there was a dose-dependent association with cycle classification (p < 0.02). Measurements from the UBM (ovarian volume, follicle count, corpora lutea count) indicate an alteration of ovarian function following pellet implantation. CONCLUSION: Assessment of estrus cyclicity indicated a dose-response relationship in the shift to a larger number of acyclic rats and longer in duration spent in the diestrus phase. Therefore, each dose in this model mimics some of the changes observed in the ovaries of women using ENG LARC and provides an opportunity for investigating the impacts on non-reproductive tissues in the future.


Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Desogestrel/administración & dosificación , Implantes de Medicamentos/administración & dosificación , Estro/efectos de los fármacos , Modelos Animales , Progestinas/administración & dosificación , Animales , Anticonceptivos Femeninos/metabolismo , Desogestrel/metabolismo , Relación Dosis-Respuesta a Droga , Implantes de Medicamentos/metabolismo , Estro/metabolismo , Femenino , Humanos , Progestinas/metabolismo , Ratas , Ratas Sprague-Dawley , Roedores
18.
J Reprod Dev ; 67(2): 135-139, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33583915

RESUMEN

Since the 1970s, luteolytic doses used for synchronizing estrus in dairy cattle have remained unchanged. This study aimed to evaluate the dose-response effect of prostaglandin F2α (PGF2α), which is used for synchronizing estrus, and subsequent fertility in cows with two or more corpora lutea (CL). The study population consisted of 1,683 cows with a single CL (1CL), 501 cows with multiple CL receiving a single dose of PGF2α (2CL1), and 252 cows with multiple CL receiving a 1.5 × PGF2α dose (2CL1.5). Cows with a single CL (n = 1,245) showed estrus significantly (P < 0.01) earlier (3.01 ± 1.23 days; mean ± SD) than cows with multiple CL (n = 287; 3.33 ± 1.69 days). Using 1CL cows as reference, the odds ratio (OR) for the estrus response in 2CL1 cows was 0.13 (P < 0.0001), whereas the ORs for estrus response and pregnancy of 2CL1.5 cows were 1.8 (P = 0.0001) and 1.7 (P = 0.001), respectively. Based on the results for only the 2CL1 cows, the OR for the estrus response was 0.7 (P = 0.01) for cows producing ≥ 45 kg of milk at treatment, compared to the remaining cows producing < 45 kg of milk. Our results showed that the presence of multiple CL reduced the estrus response to that induced by a single PGF2α dose and milk production was inversely associated with this response, whereas an increased PGF2α dose improved the estrus response. Therefore, an increase in the standard PGF2α dose is recommended.


Asunto(s)
Cuerpo Lúteo/fisiología , Dinoprost/metabolismo , Sincronización del Estro/métodos , Inseminación Artificial/veterinaria , Lactancia , Preñez , Animales , Bovinos , Cuerpo Lúteo/metabolismo , Estro/efectos de los fármacos , Femenino , Fertilidad/efectos de los fármacos , Luteólisis , Leche , Oportunidad Relativa , Ovulación , Embarazo , Prostaglandinas/química
19.
J Reprod Dev ; 67(2): 83-88, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33518696

RESUMEN

Estrus synchronization requires multiple treatments of hormonal drugs, requiring considerable time and cost. The aim of the present study was to develop an estrus synchronization protocol using intravaginal administration of estradiol benzoate (EB) capsules in goats. Two types of capsules were prepared: an EB capsule that melted immediately after administration and a sustained-release (SR) EB capsule that dissolved slowly and reached a peak after 24 h. Goats with functional corpus lutea were intramuscularly treated with prostaglandin F2α (PG). At 24 h after PG administration, goats were administered 1 mg of EB solution intramuscularly (PG + 24IM; n = 6) or 1 mg of EB capsule intravaginally (PG + 24EB; n = 6). The SR EB capsule was administered intravaginally at the time of PG administration (PG + SR; n = 6). The control group (n = 6) received only PG. All groups showed estrus within 72 h after PG administration. The onset of estrus did not differ significantly between the PG + 24IM and PG + SR groups but was earlier than in the control group. Estradiol concentration in the PG + SR group peaked at 11.5 ± 6.1 h after EB and PG administration. Peak estradiol concentrations were not significantly different between the PG + 24IM and PG + SR groups (78.0 ± 25.8 and 64.0 ± 38.1 pg/ml, respectively), and were higher than the PG + 24EB and control groups (27.3 ± 8.8 and 14.6 ± 6.1 pg/ml, respectively). These results suggest that intravaginal administration of an EB capsule with a sustained-drug release base is applicable for estrus synchronization, as an alternative to intramuscular administration.


Asunto(s)
Administración Intravaginal , Estradiol/análogos & derivados , Sincronización del Estro/métodos , Estro/efectos de los fármacos , Animales , Preparaciones de Acción Retardada , Estradiol/administración & dosificación , Femenino , Cabras , Inseminación Artificial/veterinaria , Polímeros/química , Pronóstico
20.
Behav Brain Res ; 397: 112952, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33017640

RESUMEN

Low concentrations of ovarian hormones, among other factors, are associated with greater vulnerability to negative effects of environmental stressors and may trigger anxiety symptoms in females. The flavonoid chrysin (5,7-dihydroxyflavone) exerts anxiolytic-like effects in male and ovariectomized female rats, but it is unknown if chrysin could reduce anxiety-like behavior that naturally occurs through the ovarian cycle phases. The present study evaluated the effect of chrysin on anxiety-like behavior associated with the ovarian cycle phases in rats and the participation of γ-aminobutyric acid-A (GABAA) receptors in these actions. The acute effects of chrysin (2 mg/kg) were investigated in female cycling Wistar rats in the elevated plus maze, locomotor activity test, and light/dark test. Diazepam (2 mg/kg) was used as reference anxiolytic drug. The participation of GABAA receptor in the anxiolytic actions of chrysin was explored by pretreating the rats with the noncompetitive GABAA chloride ion channel antagonist picrotoxin (1 mg/kg). Chrysin and diazepam prevented anxiety-like behavior that was associated with the metestrus-diestrus phase in both the elevated plus maze and light/dark test, and these effects were reversed by picrotoxin, with no significant changes in spontaneous locomotor activity. No significant motor effects of chrysin were detected in either behavioral test during proestrus-estrus or metestrus-diestrus phases, whereas diazepam produced motor hypoactivity in the locomotor activity test during proestrus-estrus phase. These results indicate that the flavonoid chrysin prevents anxiety-like behavior that naturally occurs during metestrus-diestrus in two unconditioned models that are used to evaluate anxiety-like behavior, and these effects were mediated by actions on GABAA receptors.


Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Conducta Animal/efectos de los fármacos , Diazepam/farmacología , Ciclo Estral/efectos de los fármacos , Flavonoides/farmacología , Antagonistas de Receptores de GABA-A/farmacología , Animales , Ansiolíticos/administración & dosificación , Diazepam/administración & dosificación , Diestro/efectos de los fármacos , Estro/efectos de los fármacos , Femenino , Flavonoides/administración & dosificación , Antagonistas de Receptores de GABA-A/administración & dosificación , Metestro/efectos de los fármacos , Picrotoxina/farmacología , Proestro/efectos de los fármacos , Ratas , Ratas Wistar
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