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1.
Cryo Letters ; 40(6): 352-356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33966062

RESUMO

BACKGROUND: Cryopreservation induces spermatic cryo capacitation, which can decrease thawed sperm fertilizing capability. OBJECTIVE: To evaluate the effect of uterus-vaginal union protein factors to inhibit sperm cryo capacitation and maintain viability and fertilizing capability of rooster spermatozoa. MATERIALS AND METHODS: Rooster spermatozoa was cryopreserved using Lake extender supplemented with different hen's uterus-vaginal junction protein concentrations, to determine spermatic viability, sperm physiological condition and fertilizing capability in vivo. RESULTS: It was possible to induce spermatic decapacitation in vitro, inhibiting cryo capacitation and allowing fertility results comparable to those obtained with fresh semen. CONCLUSION: Uterus-vaginal protein extracts induce spermatic decapacitation in vitro.

2.
Theriogenology ; 68(4): 646-53, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17602731

RESUMO

The enzyme P450-aromatase (P450-Aro) is essential for the conversion of androgens to estrogens. The objective was to study the expression and distribution of P450-Aro in goat placentae throughout pregnancy. For this purpose, we used reverse transcription-polymerase chain reaction (RT-PCR) with primers derived from the ovarian cDNA sequence found by our group. The expression of P450-Aro mRNA was first detected by in vitro RT-PCR in cotyledons at 4 months and was still present at term. Based on in situ RT-PCR, cotyledon microvilli expressed P450-Aro mRNA early in pregnancy; the signal was detected in the syncytiotrophoblast and in non-fused cytotrophoblasts inside the microvilli, but was scarce in the interstitial cells of the villous core. In the last 2 months of pregnancy (including at term), the expression of P450-Aro mRNA was still detected in the syncytiotrophoblast. However, P450-Aro was never detected in the caruncule (regardless of stage of pregnancy). In conclusion, P450-Aro was expressed in the goat placenta microvilli starting early in pregnancy; the expression and distribution of the enzyme increased throughout pregnancy and was still present at term.


Assuntos
Aromatase/biossíntese , Cabras/metabolismo , Placenta/enzimologia , Animais , Aromatase/genética , Aromatase/metabolismo , Feminino , Cabras/genética , Histocitoquímica/veterinária , Gravidez , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
3.
J Mater Chem B ; 4(6): 1035-1039, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27127630

RESUMO

We present a versatile and facile method to enhance user-control of small molecule drug release from a poly(ethylene glycol)-based hydrogel using the host/guest complex formed between an azobenzene derivative guest and a ß-cyclodextrin host. A model drug is formed from a short peptide containing a fluorophore and an azobenzene functional group on one terminus. Upon irradiation with UV light, azobenzene isomerization leads to decreased complex formation and an on-demand acceleratation of the release rate of an entrapped model drug.

4.
Theriogenology ; 64(9): 1889-97, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15963559

RESUMO

Oxytocin and vetrabutin chlorhydrate (VC) are used to reduce the duration of farrowing in swine. The objective of the present study was to evaluate the use of these products on intra-partum stillbirth (IPS) rate and asphyxia. At the onset of parturition, sows (n=180) were allocated to receive 2 mL of saline (control group), oxytocin (40 IU i.m.) or 100mg of VC per 60 kg of body weight, with all treatments given i.m. Oytocin-treated sows had a higher number of IPS than the VC and Control groups (means, 1.2, 0.8 and 0.6, respectively; P<0.001), and the highest percentage of ruptured umbilical cords (76.0, 9.4 and 37.5%; P<0.003). There were differences among groups for duration of farrowing (means, 163.0, 211.2 and 306.9 min in the oxytocin, VC and control groups; P<0.001), interval between piglets (13.9, 19.2 and 28.1 min; P<0.001), and in IPS, the incidence of ruptured umbilical cords was 76.0, 9.4 and 37.5% (P<0.003) and absence of a fetal heartbeat was 53.3, 16.9 and 12.5% (P<0.05). Although oxytocin decreased both duration of farrowing and interval between piglets by approximately 50% relative to control sows, it resulted in a significantly higher rate of IPS, in association with a much higher incidence of ruptured umbilical cord and absence of a fetal heartbeat. Treatment with VC reduced farrowing duration by approximately 1.5h, with an IPS rate that was not significantly different from controls but significantly lower than that of oxytocin-treated sows.


Assuntos
Asfixia/veterinária , Ocitocina/efeitos adversos , Natimorto/veterinária , Doenças dos Suínos/epidemiologia , Animais , Asfixia/epidemiologia , Asfixia/etiologia , Feminino , Parto , Gravidez , Ruptura Espontânea/veterinária , Suínos , Doenças dos Suínos/etiologia , Fatores de Tempo , Cordão Umbilical , Contração Uterina/efeitos dos fármacos , Contração Uterina/fisiologia
5.
Am J Cardiol ; 88(10): 1169-72, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11703965

RESUMO

The causes and significance of postoperative ectopic atrial tachycardia (EAT) remain unknown. To identify factors associated with postoperative EAT in children after cardiac surgery, we retrospectively studied pre-, intra-, and postoperative variables. The median age for postoperative EAT cases was younger than the general population admitted for cardiac surgical procedures (6 vs 17 months old, p = 0.09). Trends for EAT cases included lower preoperative oxygen saturation (84% vs 99%, p = 0.001), more pre- and postoperative inotropic support, and atrial septostomy (24% vs 6%, p = 0.08). EAT cases had longer cardiopulmonary bypass times and clamp times (115 vs 88 minutes, p = 0.08; 63 vs 46 minutes, p = 0.03, respectively) and had a prolonged intensive care unit stay (10 vs 3 days, p <0.001). Deaths were recorded in 2 of 17 EAT cases versus 0 of 36 randomly selected controls (p = 0.10). EAT resolved before discharge in 10 of 16 surviving patients. The etiology of EAT appears to be multifactorial, and may include disruption of atrial septum, longer pump times, need for inotropic support, and potassium depletion. Thus, young, ill, cyanotic patients were most at risk for postoperative EAT. Although EAT was associated with prolonged intensive care, it resolved in most cases over time.


Assuntos
Cardiopatias Congênitas/cirurgia , Complicações Pós-Operatórias , Taquicardia Atrial Ectópica/etiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Estudos Retrospectivos
6.
Arch Med Res ; 27(1): 49-55, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8867367

RESUMO

Large superovulatory doses of gonadotrophins result in reduced fertility in laboratory and large domestic animals and it has been postulated that some of the superovulated oocytes are derived from abnormal follicles which would not ovulate under normal physiological stimuli. Follicular growth, follicular maturation and atresia, ovulation and the nidation of the fertilized oocyte require intense tissue remodelation which can be accomplished only through the action of hydrolytic enzymes. We have studied the activities and sub-cellular distribution of three lysosomal enzymes (acid phosphatase, N-acetyl-beta-D-glucosaminidase and beta-glucuronidase) in the follicular fluid, granulosa and theca cells of preovulatory follicles and in the endometrial tissue of immature Wistar rats injected with 4 (control) or 40 (superovulated) IU of pregnant mare serum gonadotrophin (PMSG). Enzyme activities were from four to ten times higher in theca than in granulosa cells. This difference was particularly important in the case of beta-glucuronidase. Large preovulatory follicles tended to have higher activities of lysosomal enzymes in the free fraction of all the compartments studied. This difference was remarkable in theca cells where free enzymes would be required to help ovulation. Forty IU of PMSG induced higher activities of acid phosphatase in theca and granulosa cells than 4 IU, but in endometrial tissue this latter dose of PMSG was more efficient to induce higher activities of this enzyme. The endometrial bound fraction of N-acetyl-beta-D-glucosaminidase was almost three times higher than the free activity. This behavior was also observed in endometrial beta-glucuronidase but only in the control rats. The results observed in follicular fluid were less homogeneous. The activities of glucosaminidase and acid phosphatase were two to three times higher in rats overstimulated with 40 IU of PMSG than in the control rats, whereas the activities of beta-glucuronidase were lower in the superovulated rats. Our results suggest that alterations in the process of tissue remodeling required for ovulation of mature, normal oocytes and for nidation of the fertilized ovum may be important factors to explain pregnancy failure in the PMSG superovulated female.


Assuntos
Endométrio/enzimologia , Gonadotropinas Equinas/farmacologia , Lisossomos/enzimologia , Folículo Ovariano/enzimologia , Superovulação/fisiologia , Animais , Feminino , Ratos , Ratos Wistar
7.
Anim Reprod Sci ; 47(3): 211-28, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9329863

RESUMO

Metalloproteinases are an important group of hydrolytic enzymes which participate in interstitial matrix degradation during tissue remodelling processes and therefore may be required during follicular growth and maturation. The activity of metalloproteinases (collagenases, gelatinase, and Pz-peptidase), was measured during growth, maturation and atresia of goat antral follicles. These follicles (n = 67) were separated by size and also classified into four groups: non-atretic (Group I); early atretic (Stage I) (Group II); moderately atretic (Stage II) (Group IIIa); and, late atretic (Stage III) (Group IIIb). Pz-peptidase was greater in granulosa than in thecal cells, and almost absent in follicular fluid. In non-atretic follicles, activity in granulosa cells increased with increasing follicle size, whereas activity peaked in 3-6 mm follicles in thecal cells. Atresia was associated with declining activity in thecal cells from follicles in the 3-6 mm range and in granulosa cells from the > 6 mm range. Interstitial collagenase activity was significant and similar in granulosa and thecal cell extracts and low in follicular fluid from non-atretic follicles. Activity increased significantly in thecal cells, but decreased significantly in granulosa cells from large (> 6 mm) non-atretic follicles. Atresia was associated with declining activity in both types cells and increasing activity in follicular fluid. Gelatinase activity was some times associated with five regions corresponding to molecular weights of 22.1, 30.7, 39.6, 63.8 and 71.4 kDa, and rarely at 91.3 and 81.2 kDa. Overall activity declined with atresia in thecal cells from follicles in the 3-6 mm range, but not in those > 6 mm. In granulosa cells from follicles 3-6 mm, activity varied widely with stage of atresia, while in cells from follicles > 6 mm, activity was greatly increased in atretic follicles.


Assuntos
Atresia Folicular/fisiologia , Cabras/fisiologia , Metaloendopeptidases/análise , Folículo Ovariano/enzimologia , Animais , Colagenases/análise , Colagenases/metabolismo , Densitometria , Feminino , Líquido Folicular/enzimologia , Líquido Folicular/metabolismo , Gelatinases/análise , Gelatinases/metabolismo , Células da Granulosa/enzimologia , Células da Granulosa/metabolismo , Metaloendopeptidases/metabolismo , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , Gravidez , Células Tecais/enzimologia , Células Tecais/metabolismo
8.
Plant Dis ; 81(1): 49-52, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30870946

RESUMO

The potential of antagonistic bacteria from paddy water, rhizosphere soils, sclerotia, and rice plants to control "bakanae" caused by Fusarium moniliforme was assessed. Experiments were conducted to determine the in vitro antibiosis and effect of bacteria on seed germination. Out of 441 isolates, 113 were inhibitory to mycelial growth of the pathogen. Bacterial strains were classified into three groups based on effect on seed germination: (i) those that promoted germination and enhanced seedling vigor; (ii) those that had no effect on germination; and (iii) those that were deleterious and inhibited germination. Bacterization of naturally infected seeds reduced bakanae incidence in seedbox and seedbed tests. In a seedbed experiment with IR 58 seeds soaked in suspensions of bacterial strains, bakanae incidence and disease control ranged from 0.9 to 6.8% and 71.7 to 96.3%, respectively. From the 3 years of field trials, 10 strains reduced bakanae. Five strains consistently reduced bakanae, but the other five exhibited variable effects among trials. Specificity of suppression by antagonistic bacteria against different pathogenic isolates of F. moniliforme from various locations in the Philippines was observed.

9.
Ginecol Obstet Mex ; 65: 349-56, 1997 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-9324472

RESUMO

Follicular fluid (FF) is of great importance in Assisted Procreation Programmes, because it constitutes the micro-environment of the follicle that regulates the development of the oocyte and participates in the capacitation of the spermatozoa. The biochemical composition of FF is influenced by the state of follicle maturation and reciprocally the content of the fluid predicts the success of the subsequent follicular maturation and pregnancy. In most of the species the high concentrations of estradiol are common in the follicles of intermediate maturity, the progesterone in the mature ones and the androgens in the atresics ones. Estradiol concentration is associated with the fertilizing capacity of the oocytes and its metabolites stimulate the progesterone production. Moreover, the FF regulates the action of the gonadotrophins, because it contains factors that help the union of these with its receptor. The FF contributes providing factors that inhibit and stimulate the meiosis. It contains factors that stimulates oocyte maturation, or that block the ability of the cortical granules to modify the components of the pellucid zone. The exposition of spermatozoons with this fluid helps the acrosomal reaction, the spermatic motility and the ovum penetration.


Assuntos
Líquido Folicular/fisiologia , Fase Folicular , Oócitos/fisiologia , Gonadotropina Coriônica/fisiologia , Feminino , Humanos , Inseminação Artificial , Masculino , Gravidez , Espermatozoides/fisiologia
10.
Theriogenology ; 78(2): 455-61, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22538006

RESUMO

The objective was to measure the effects of VC (a uterotonic drug with vasodilator effects) in eutocic and dystocic sows, on the acid-base balance and some vitality traits of piglets at birth. Farrowing was induced with prostaglandin F2α. Four groups of sows (20 sows/group) were monitored; Groups 1 and 2 were eutocic sows, whereas Groups 3 and 4 were dam-fetal dystocic sows. Groups 1 and 3 (control) were given saline, whereas Groups 2 and 4 were given VC im (1.66 mg/kg of body weight) after the first piglet was born. Piglets' physio-metabolic performance was monitored peripartum. Treatment with VC reduced (P<0.0001) the percentage of intrapartum stillbirths in sows either with eutocic (5.2 vs. 10.0%) and dystocic (7.6 vs. 16.7%) farrowings and increased (P<0.0001) the number of pigs born alive without any evidence of AFS (89.9 vs. 79.9%, eutocic and 81.6 vs. 65.2%, dystocic). In addition, for the group of pigs with no acute fetal suffering (AFS), VC treatment enhanced survival responses with a half point grater vitality score in Group 4; it also reduced the latency to first teat contact by 6 min (P<0.05) in both treated groups compared to controls; and it improved the condition of the pigs' umbilical cord, with more adhered (98 vs. 86% in eutocic and 88 vs. 80% in dystocic; P<0.05) and less ruptured cords. Moreover, VC reduced the severity of adverse physio-metabolic indicators and the acid-base balance of piglets with AFS at birth by lowering blood lactate (89.8 vs. 93.5 mmol/L in eutocic groups and 94.6 vs. 100.2 mmol/L in dystocic groups; P<0.05), PaCO2 and Ca2+, and by increasing blood pH, HCO3 and PaO2 levels (P<0.05).


Assuntos
Equilíbrio Ácido-Base/efeitos dos fármacos , Benzilaminas/uso terapêutico , Distocia/veterinária , Ocitócicos/uso terapêutico , Animais , Animais Recém-Nascidos , Distocia/tratamento farmacológico , Feminino , Gravidez , Natimorto/veterinária , Suínos , Cordão Umbilical
11.
Rev. med. vet. zoot ; 60(2): 79-85, may.-ago. 2013. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-695863

RESUMO

El objetivo de este estudio fue describir los parámetros hematológicos en 69 polluelos en cautiverio de origen silvestre, clínicamente sanos, menores de tres meses de edad, en cuatro especies de psitácidos: Pionus senilis (n = 18), Amazona albifrons (n = 15), Amazona autumnalis (n = 25) y Amazona oratrix (n = 11), procedentes de la región central de México. Para determinar dichos parámetros, de cada ejemplar se obtuvieron 500 µl de sangre por punción de la vena braquial. En las cuatro especies citadas, el porcentaje del hematocrito fue de 56,4 ± 3,36; 51 ± 6,52; 47,6 ± 6,47 y 53,8 ± 9,26; el VCM en fl fue de 184,6 ± 13,4; 142,0 ± 25,4; 106,3 ± 11,7 y 162,3 ± 71,9; la cuenta eritrocítica fue de 4,7 ± 2,1 x10(6)/µl; 6,1 ± 8,2 x10(6)/µl; 6,9 ± 1,2 x10(6)/µl y 5,4 ± 1,1 x10(6)/µl; y la cuenta leucocitaria de 3,06 ± 0,15 x10³/µl; 3,62 ± 0,24 x10³/µl; 4,48 ± 0,36 x10³/µl y 3,56 ± 0,71 x10³/µl respectivamente para P. senilis, A. albifrons, A. autumnalis y A. oratrix. Se constató tendencia a la heterofilia en A. albifrons y A. oratrix, lo cual puede ser de gran utilidad para un diagnóstico cada vez más preciso en la clínica de aves en cautiverio.


The aim of this study, conducted in central Mexico, was to describe the hematological parameters in 69 wild chicks of psittacine kept in captivity, younger than three months of age of four different species: Pionus senilis (n = 18), Amazona albifrons (n = 15), Amazona autumnalis (n = 25) and Amazona oratrix (n = 11). All parrots were sampled to obtaind 500 µl of blood for quantifying hematological parameters. Hematocrit percentage was 56.4 ± 3.36, 51 ± 6.52, 47.6 ± 6.47 and 53.8 ± 9.26; the MCV (fl) was 184.6 ± 13.4, 142.0 ± 25.4, 106.3 ± 11.7 and 162.3 ± 71.9; the erythrocyte count was, 4.7 ± 2.1x10(6)/μl, 6.1 ± 8.2 x10(6)/μl, 6.9 ± 1.2 x10(6)/μl and 5.4 ± 1.1 x10(6)/μl, and leukocyte count was of 3.06 ± 0.15 x10³/µl, 3.62 ± 0.24 x10³/µl, 4.48 ± 0.36 x10³/µl y 3.56 ± 0.71 x10³/µl respectively for P. senilis, A. albifrons, A. autumnalis y A. oratrix. There was a trend to heterophilia in A. oratrix and A. albifrons, which represents a contribution that may be useful for more precise diagnosis in avian clinical practice.

12.
Pediatr Cardiol ; 20(3): 224-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10089252

RESUMO

The following is a case report of a 1-month-old patient who developed adverse hemodynamic sequelae during the use of nitric oxide (NO) in the postoperative period for pulmonary hypertension after correction of total anomalous pulmonary venous return. At the time of diagnosis, the patient had evidence of systemic right ventricular pressures estimated by continuous-wave Doppler. He was sedated and paralyzed for hyperventilation in preparation for surgery and underwent pulmonary vein confluence to left atrial anastomosis. Postoperative pulmonary hypertension was managed by hyperventilation, sedation, and paralysis until a sudden onset of systemic-level pulmonary pressure required NO therapy. Satisfactory results were obtained in minutes, but a rebound pulmonary hypertension occurred with concomitant systemic hypertension and no radiographic changes. We suspected left atrial hypertension secondary to a sudden increase in pulmonary blood flow to an noncompliant left ventricle. Discontinuation of NO resulted in stabilization of the hemodynamic profile of the patient and he continued to be managed with paralysis, hyperventilation, and sedation. Based on this experience we suggest that NO should be used with caution in patients with obstructive lesions at the atrial level prior to surgery (mitral valve stenosis and cor triatriatum) or in patients with a poorly compliant left ventricle (cardiomyopathy and left ventricular dysfunction). These entities are unable to tolerate a sudden increase in pulmonary blood return thus creating paradoxical pulmonary hypertension.


Assuntos
Átrios do Coração/cirurgia , Hemodinâmica/efeitos dos fármacos , Óxido Nítrico/efeitos adversos , Veias Pulmonares/anormalidades , Veias Pulmonares/cirurgia , Vasodilatadores/efeitos adversos , Administração por Inalação , Anastomose Cirúrgica , Seguimentos , Humanos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/fisiopatologia , Recém-Nascido , Masculino , Complicações Pós-Operatórias , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/cirurgia
13.
Andrologia ; 33(2): 113-21, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11350375

RESUMO

Mammalian spermatozoa maintain precisely regulated ionic gradients that must be modified during capacitation and the acrosome reaction. In other cell types, ionic gradients are mainly regulated by the presence in plasma membranes of three metabolically different types of ATPases. The modifications induced during in vitro capacitation of rabbit spermatozoa by the specific inhibition of V-type H+-ATPases with bafilomycin A were studied. We used chlortetracycline binding to rabbit spermatozoa to monitor capacitation, and the coomassie brilliant blue method to identify acrosome-reacted sperm cells. There was a significant difference between the percentage of epididymal (66 +/- 7%) and ejaculated (43 +/- 11%) spermatozoa capacitated in vitro, after a 6-h incubation period in the presence of Ca2+ without ATPase inhibitor. The presence of bafilomycin significantly reduced these numbers (25 +/- 11 and 16+/- 8%, epididymal and ejaculated spermatozoa, respectively) and eliminated the difference. Ejaculated spermatozoa capacitated in the absence of bafilomycin showed a linear increase in the percentage of acrosome reactions induced by the addition of A23187 (12 +/- 5, 23+/- 6 and 31 +/- 5 after 15, 30 and 45 min). The presence of 0.2 micromol l-1 bafilomycin during the capacitation incubation induced a significant decrease in the acrosome reaction percentages (4 +/- 2, 8 +/- 3 and 14 +/- 4 after 15, 30 and 45 min). The addition of bafilomycin after the capacitating period had no effect upon the induction of the acrosome reaction by A23187. These results indicate that vacuolar ATPases play an important role during rabbit sperm capacitation. However, once the spermatozoa have been capacitated, V-type ATPases do not have a significant participation during the acrosome reaction.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Macrolídeos , Lectinas de Plantas , ATPases Translocadoras de Prótons/antagonistas & inibidores , Capacitação Espermática/efeitos dos fármacos , ATPases Vacuolares Próton-Translocadoras , Reação Acrossômica , Animais , Calcimicina/farmacologia , Clortetraciclina , Ejaculação , Epididimo/citologia , Fertilização in vitro , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Ionóforos/farmacologia , Lectinas , Masculino , Coelhos , Motilidade dos Espermatozoides
14.
Arch Androl ; 48(5): 389-95, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12230825

RESUMO

Modifications of semen quality related to ejaculation frequency is one of the most important and neglected factors from the standpoint of artificial insemination or sperm competition. New Zealand white rabbits (Oryctolagus cuniculus) offer an advantageous experimental model because they have characteristic sexual behavior, they present rapid ejaculation after a single intromission, they have a very short interval between successive ejaculations, and semen can be easily collected. The authors studied the modifications on sperm quality (semen volume, sperm concentration, sperm motility) produced by 14 consecutive ejaculations recovered every 15 min using stimulus females and an artificial vagina. Bucks were exposed every 15 min to a sexually receptive female. After each ejaculation the female was removed and reintroduced 15 min later. Sperm concentration showed a clear biphasic conduct. The amount of spermatozoa per milliliter decreased rapidly until ejaculate number 6, showed a highly significant increase in ejaculates 7-9, and decreased to nil in the last 2 ejaculates. Total number of ejaculated spermatozoa was 557 x 10(6), 76% of which were recovered from the first 4 ejaculates. Ejaculate volume also showed a biphasic conduct. In the first ejaculates the volume decreased linearly until ejaculate number 6, showed a significant increase in ejaculates 7-10, and then decreased. The total semen volume recovered during the experiment was 2.44 mL, 40% of which (0.98 mL) was recovered from the first 2 ejaculates. Individual motility in the first 6 ejaculates was preferentially progressive (60% of the sperms) and turned to random or in situ from the seventh ejaculate up. The proportion of spermatozoa with cytoplasmic droplets increased from ejaculates 6 and 7 up. The results seem to reflect an acceleration of semen transport through the epididymis when the demands for spermatozoa increase.


Assuntos
Sêmen , Espermatozoides/fisiologia , Animais , Ejaculação , Feminino , Masculino , Coelhos , Fatores de Tempo
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