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1.
Animals (Basel) ; 13(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37958160

RESUMO

Spirulina platensis (SP) is a protein-rich dietary supplement that improves animal reproductive traits. This study investigated the effect of SP supplementation on puberty onset, semen characteristics, scrotal circumference (SC), libido, and hormone concentrations in Sahrawi and Jabbali bucks. The study was conducted in 36 bucks, divided into three groups (n = 6/group), for 70 days. The rations included the following: (1) Control feed (Con) with 14% crude protein and 11.97% MJ/kg DM energy; (2) Con with 2 g SP/head/day SP treatment (T1) and (3) Con with 4 g SP/head/day treatment (T2). The mean (±SEM) SC of both SP groups in the Sahrawi breed was significantly higher (p ≤ 0.05) compared to the Con. The mean of the semen volume significantly increased (p ≤ 0.05) in the SP group than in the Con group in both breeds. SP groups vs. Con groups had increased sperm concentration in Sahrawi bucks than Jabbali bucks. Mean serum luteinizing hormone (LH) and testosterone (Tes) concentrations in Jabbali bucks were significantly higher (p ≤ 0.05) in the SP groups compared to Sahrawi bucks. SP improved the SC, semen quality, libido, sperm concentration, and LH and Tes concentrations in both breeds. The results of the current study suggest that adding SP to the diet may have the ability to improve the semen quality of the local Omani bucks.

2.
Theriogenology ; 179: 230-236, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34896745

RESUMO

This study examines the effect of advancing the breeding season on the reproductive performance of dromedary camels under an intensive management system. Using a synchronization protocol, timed natural mating in female camels was carried out either in September (2 months ahead of the natural breeding season, n = 182) or December (peak breeding season, n = 115). The ovarian responses (size of the dominant follicle at the time of mating and ovulation), pregnancy rate, and pregnancy losses were evaluated using ultrasonography. Blood samples were collected after mating to assess progesterone concentrations by RIA. The libido of male camels (n = 13) was evaluated objectively. Results showed that the percentage of female camels with an optimal sized follicle (11-17 mm) for breeding at the time of mating was lower in September compared to December (81.9 vs 91.3%, P = 0.03). The libido of male camels was lower in September than in December (P <0.001). The ovulation rate (86.3 vs 93.9%, P = 0.04), size of the ovulated follicle (12.7 ± 0.1 vs 13.7 ± 0.2 mm, P <0.001), pregnancy rates on Day 14 (47.8 vs 72.2%, P <0.001) and Day 90 (38.5 vs 60.9%, P <0.001) after mating was lower in September compared to December. However, pregnancy loss was not affected between months (15.7 vs 19.5%, P = 0.3). Among pregnant camels, the progesterone concentrations on Days 6, 8, 10, 12 and 14 after mating were lower in September as compared to December (P <0.001). In non-pregnant camels, the progesterone concentrations on Days 6, 8 and 10 after mating were also lower in September as compared to December (P <0.001). In conclusion, advancing the breeding season by two months, significantly affects the reproductive performance of dromedary camels, yet, acceptable pregnancy rates can be achieved.


Assuntos
Aborto Animal , Camelus , Animais , Feminino , Masculino , Folículo Ovariano , Gravidez , Progesterona , Reprodução , Estações do Ano
3.
Saudi J Biol Sci ; 29(3): 1577-1584, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35280569

RESUMO

Diluents and various biological products have been used in different animal species, with promising outcomes in post-thaw sperm quality. Nevertheless, only a few reports are available for the semen of Arabian horses. Edible bird's nest (EBN) - a product of the salivary secretions of swiftlet species is widely known to have both antioxidant and anti-inflammatory properties. Presently, there is no data available on the role of EBN supplemented in different extenders and its effect on semen quality in stallion semen. Two in vitro experiments were conducted to examine the effects of edible bird's nest (EBN) on the quality of chilled and post-thawed cryopreserved Arabian stallion spermatozoa. In experiment one, 10 ejaculates were collected, divided into two equal parts, diluted using EquiPlus® and INRA 96® and supplemented with 0 % (control), 0.12 %, 0.24 % EBN concentrations. The semen samples were stored at 5 ℃ and observed at 0, 24, and 48 h. Sperm kinetics variables (% total motility [TM] and progressive motility [PM], curvilinear velocity; VCL, straightness; VSL, average path velocity; VAP) were analyzed using computerized assisted sperm analysis. For chilled semen, there was no significant difference in any of the sperm quality parameters between control (0 %), 0.12 %, and 0.24 % EBN supplementation either in INRA96® or EquiPlus®. In experiment two, nine ejaculates were diluted and cryopreserved using EquiPlus Freeze® and INRA Freeze® containing 0 %, 2.4 %, and 4.8 % EBN, and evaluated after thawing. Sperm kinetics, DNA integrity and antioxidant capacity - Biological Anti-oxidant Potential (BAP) and Reactive Oxygen Metabolites (d-ROMs) test were evaluated. In chilled semen, there was no significant difference in any of the sperm quality parameters between control (0 %), 0.12 %, and 0.24 % EBN supplementation either in INRA96® or EquiPlus®. For frozen semen supplemented with 2.4 % and 4.8 % EBN had higher sperm motility parameters compared to control in INRA Freeze® and EquiPlus Freeze®, but the values were not statistically significant (P > 0.05). Also, EBN supplementation had no significant effects on the DNA integrity, biological antioxidant potential, and reactive oxygen metabolites. EBN supplementation had no significant effects on sperm quality and antioxidant status in chilled and frozen Arabian Stallion semen. Future studies might consider different methods of EBN preparation and concentrations to elucidate the potential biological impact of EBN in Arabian stallion semen.

4.
Anim Reprod ; 18(2): e20200027, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34221142

RESUMO

The aim of this study was to evaluate the effects of adding different concentrations of edible bird's nest (EBN) which is secreted by swiftlet birds (Aerodramus fuciphagus), into EquiPlus® and E-Z Mixin® extenders on the quality of chilled Arabian stallion semen at various storage times (0, 24 and 48 h). Ten ejaculates were collected from five stallions, and diluted using the two extenders containing 0% (control), 0.12%, 0.24% and 0.24% of EBN + seminal plasma (SP). All the diluted semen samples were then cooled and stored at 5 °C, and examined at 0, 24 and 48 h. Sperm kinetic parameters were assessed using computer assisted sperm analysis (CASA) and viability were assessed using Hoechst33342/PI stain. In both extenders, total motility (TM) and progressive motility (PM) were significantly higher at 0.12% and 0.24% compared to 0.24% + SP at 24 and 48 h. At 0.12%, E-Z mixin® treated semen had significantly higher TM and PM than EquiPlus® at 24 and 48 h. At 0.12% and 0.24%, average path velocity (VAP), straight-line velocity (VSL) and curvilinear velocity (VCL) were significantly higher in E-Z mixin® treated semen compared to EquiPlus® at 24 and 48 h. Comparisons between the two extender types at different concentrations of EBN showed no significant difference in lateral head amplitude (ALH), linearity (LIN), straightness (STR), beat cross frequency (BCF) and viability, irrespective of the storage time. The percentage of viable was significantly higher in E-Z mixin® than EquiPlus® at 0 and 48 h in control and 0.12%. Supplementation of the E-Z mixin® extender with 0.12% and 0.24% EBN concentrations in the absence of SP provided better CASA parameters such as TM, PM, VAP, VSL, and VCL at 24 and 48 h storage time. In conclusion, the results of this study indicated that chilled semen from Arabian stallion that was extended using E-Z mixin® and supplemented with 0.12% and 0.24% EBN concentrations performed better and yielded superior results in sperm kinetic parameters and % viable compared to EquiPlus® at 24 and 48 h storage time.

5.
Theriogenology ; 151: 112-118, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32325323

RESUMO

This study was conducted to develop simple superovulation protocols for dromedary camels using eCG. In experiment 1, camels received either 1000, 2000, 3000, 4000, 5000 or 6000 IU eCG. In experiment 2, camels received either 400 mg FSH (Folltropin-V) twice-daily over 5 days or 3000 IU eCG. In experiment 3, camels received 3000 IU eCG either at 2, 3, 4 or 5 days after ovulation induction. Ovarian response and embryo yield were evaluated in all experiments and embryos collected from camels treated with FSH and eCG were transferred to recipients to examine pregnancy rates. The mean number of ovulations (12.6 ± 1.5 and 13.3 ± 1.2 vs 3.4 ± 0.3, 6.2 ± 0.6 and 9.3 ± 1.0, respectively) and transferable embryos (4.6 ± 1.3 and 4.8 ± 1.0 vs 1.6 ± 0.2, 2.2 ± 0.4 and 1.1 ± 0.4, respectively) with 3000 and 4000 IU eCG doses were higher compared to 1000, 2000 and 6000 IU eCG doses (P < 0.05). Doses of 5000 and 6000 IU eCG resulted in a higher number of unovulatory follicles than other doses (P < 0.05). The FSH treatment resulted in higher number of ovulatory follicles (21.8 ± 1.3 vs 14.8 ± 1.7) and ovulations (18.5 ± 1.1 vs 13.9 ± 1.4) compared to eCG (P < 0.05). However, the number of transferable embryos and pregnancy rates were similar in these treatments. The timing of eCG treatment after ovulation induction did not affect the number of ovulatory follicles and transferable embryos but eCG treatment at 5 days after ovulation induction reduced the number of ovulations (P < 0.05). In conclusion, the optimal dose of eCG to induce superovulation is 3000-4000 IU and it produces a comparable embryo yield to FSH, and can be administered at 2-4 days after ovulation induction.


Assuntos
Camelus/fisiologia , Gonadotropina Coriônica/farmacologia , Superovulação/efeitos dos fármacos , Animais , Gonadotropina Coriônica/administração & dosagem , Relação Dose-Resposta a Droga , Transferência Embrionária , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Coleta de Tecidos e Órgãos
6.
Theriogenology ; 126: 214-221, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30583224

RESUMO

This study was conducted to develop simple superovulation protocols in dromedary camels. Using two commercial FSH products, a series of experiments was conducted to evaluate the effect of different superovulation protocols on ovarian response and embryo production. In experiment 1, camels in control group (n = 15) received 400 mg Folltropin-V in a traditional protocol (FSH diluted in saline and given twice daily in decreasing doses over 5 days) and camels in split-injection (2 doses 48 h apart) groups received either 400 (n = 16, first dose: 320 mg, second dose: 80 mg) or 200 mg (n = 16, first dose: 120 mg, second dose: 80 mg) of slow-release (SR) preparation of Folltropin-V [Folltropin-V diluted in hyaluronan (5 mg/mL) solution]. In experiment 2, camels in control group (n = 13) received 2000 IU Pluset in a traditional protocol and camels in split-injection groups received either 2000 (n = 14, first dose: 1600 IU, second dose: 400 IU) or 1000 IU (n = 16, first dose: 600 IU, second dose: 400 IU) of SR preparation of Pluset (Pluset diluted in hyaluronan solution). In experiment 3, camels received SR preparation of 200 mg Folltropin-V (n = 45, first dose: 120 mg, second dose: 80 mg) or 1000 IU Pluset (n = 42, first dose: 600 IU, second dose: 400 IU) in a split-injection protocol. In experiments 1 and 2, the mean number of ovulations, corpora lutea, transferable embryos and unfertilized ova were similar (P > 0.05) between groups. In experiment 3, there was no difference (P > 0.05) between SR preparations of Folltropin and Pluset on the number of ovulatory sized (≥9 mm) follicles (15.8 ±â€¯0.9 vs 16.7 ±â€¯0.9) and transferable embryos (5.0 ±â€¯0.4 vs 5.2 ±â€¯0.5). In conclusion, split-injection of SR preparation of FSH resulted in a similar superovulatory response compared to a traditional protocol and a similar superovulatory response can be achieved with SR preparations of Folltropin-V and Pluset in a split-injection protocol.


Assuntos
Camelus/fisiologia , Hormônio Foliculoestimulante/farmacologia , Indução da Ovulação/veterinária , Técnicas de Reprodução Assistida/veterinária , Superovulação/efeitos dos fármacos , Animais , Cruzamento/métodos , Feminino , Ovário/efeitos dos fármacos , Indução da Ovulação/métodos
7.
Anim Reprod Sci ; 202: 10-20, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30658862

RESUMO

Reproductive seasonality has been reported in numerous species, including male dromedary camels, yet investigations into seasonal changes in camel semen quality have yet to be conducted. The aim of this study was to characterise the seasonal changes in camel semen quantity and quality as well as correlate these changes to testis and accessory sex gland morphology, sexual behaviour, libido and environmental factors such as day length and ambient temperature in Oman. Semen was collected twice a month for a year and testicular and accessory sex organ biometry recorded once a month via ultrasonography (n = 8 bulls). Blood samples were collected monthly to assess testosterone levels. Results indicated that testes and accessory sex glands size increased during October-April, peaking with testosterone concentrations during January (P<0.05). The sexual behaviour and libido of camels was also greater during the months of October-April (P<0.05). Attempts to collect semen were 100% successful during November-February. Semen volume, as well as sperm gross activity, concentration, motility, average path velocity and percentage with intact acrosomes were the greatest during January and decreased from May-September (P<0.05). Changes in values for semen variables, testosterone concentrations and sex organ anatomy were also highly correlated with seasonal changes in day length and ambient temperatures. In conclusion, a clearly defined reproductive season was observed in male camels in Oman ranging from December-March, with peak reproductive function occurring during December-January. To increase the success of breeding programs, matings or semen collections should be timed to occur when reproductive function is maximal.


Assuntos
Camelus/fisiologia , Fertilidade , Reprodução , Estações do Ano , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia , Testículo/fisiologia , Animais , Masculino
8.
PLoS One ; 14(11): e0224992, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31697770

RESUMO

This study was conducted to evaluate various factors affecting fertility following insemination of dromedary camels. In experiment 1, camels were either bred by natural mating (NM) or inseminated in the body of uterus with whole, split (50:50) or 1 mL of undiluted ejaculate. In experiment 2, camels were inseminated with fresh diluted semen either in the body of the uterus or tip of the uterine horn and at either the time of ovulation induction (0 h), 24 or 30 h later. In experiment 3, camels were inseminated at the tip of the uterine horn with different doses of fresh diluted semen (75, 150 or 300 x 106 motile spermatozoa) or with 150 x 106 motile spermatozoa diluted with different extenders (Green buffer, Optixcell or Triladyl). In experiment 4, camels were inseminated in the tip of the uterine horn with diluted (Triladyl or Optixcell) liquid-stored semen or diluted (Triladyl) frozen-thawed semen consisting of either 300 or 500 x 106 motile spermatozoa. The pregnancy rate in camels bred by NM was similar to camels inseminated with whole undiluted ejaculates whereas insemination with 1 mL undiluted ejaculate resulted in lower pregnancy compared to whole and split undiluted ejaculates (P < 0.05). Deposition of semen in the uterine body resulted in lower pregnancy rates compared to deposition in the tip of the horn (35.3% versus 72.2%, P < 0.05) but insemination at the time of ovulation induction and 24 h later resulted in higher pregnancy rate to camels inseminated at 30 h after induction (68.4 and 70.0% versus 23.5%; P < 0.05). Artificial insemination with 75 x 106 motile spermatozoa resulted in lower pregnancy rates compared to 150 and 300 x 106 motile spermatozoa doses (40.9% versus 65.2 and 70.0%, respectively) and pregnancy rate was not affected by extenders. Insemination of chilled motile spermatozoa stored in either Triladyl or Optixcell resulted in similar pregnancy rates, regardless of insemination dose, although an upward trend with increasing sperm number was apparent (Triladyl; 11.1% versus 21.1% and Optixcell; 5.9% versus 12.5%, for 300 x 106 and 500 x 106 groups, respectively; P > 0.05). No pregnancies were obtained with frozen thawed semen. In conclusion, this study demonstrated that the success of camel AI is highly dependent on sperm dose, location of semen deposition, timing of insemination and semen type. Further studies are required to determine the reason for the compromised fertility of preserved semen despite apparent high in vitro quality.


Assuntos
Camelus/fisiologia , Criopreservação , Inseminação Artificial , Preservação do Sêmen , Sêmen/fisiologia , Animais , Feminino , Masculino , Ovulação , Gravidez , Taxa de Gravidez , Comportamento Sexual Animal , Espermatozoides
9.
Anim Reprod Sci ; 207: 95-106, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31208848

RESUMO

This study was conducted to assess the effects of commercial extenders and storage temperature on dromedary camel sperm quality during liquid preservation. In Experiment 1, ejaculates (n = five males; replicated seven times) were split and diluted with synthetic (OPTIXcell, EquiPlus, INRA96, Bioxcell or AndroMed; Experiment 1a) or egg-yolk based (Biladyl, Green buffer or Triladyl; Experiment 1b) extenders and stored for 48 h at 4 °C. In Experiment 2, split ejaculates (n = five males; replicated six times) were used to directly compare Green buffer, OPTIXcell and Triladyl extenders over 48 h of storage at 4 °C. Ejaculates collected in Experiment 3 (n = five males; replicated five times) were diluted with Green buffer or Triladyl before chilled storage for 48 h at 4 or 15 °C. Sperm kinematics, viability and acrosome integrity were assessed during liquid storage. In Experiment 1a, there was the greatest total sperm motility (TM) in the OPTIXcell group following 24 and 48 h of storage, while in Experiment 1b, there was the greatest TM after 48 h of storage with Triladyl and Green buffer. In Experiment 2, there were greater TM and viable acrosome intact spermatozoa in the Triladyl and Green buffer than with OPTIXcell group. In Experiment 3, there was a greater TM in the Triladyl than Green buffer group at 24 and 48 h of storage regardless of storage temperature (which had no effect on sperm quality). In conclusion, camel sperm have greater viability when preserved in liquid form for 48 h following dilution with Triladyl and storage at either 4 or 15 °C.


Assuntos
Camelus , Soluções para Preservação de Órgãos/farmacologia , Refrigeração , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Sêmen/efeitos dos fármacos , Animais , Soluções Tampão , Sobrevivência Celular/efeitos dos fármacos , Gema de Ovo/fisiologia , Soluções Isotônicas/farmacologia , Masculino , Soluções para Preservação de Órgãos/química , Refrigeração/métodos , Refrigeração/veterinária , Análise do Sêmen , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Temperatura , Fatores de Tempo
10.
Theriogenology ; 119: 208-213, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031367

RESUMO

This study was designed to evaluate the use of resynchronization (Resynch) protocol in dromedary camels. In experiment 1, the effect of initiation of Resynch protocol with GnRH treatment on Day 14 ±â€¯2 after timed breeding (TB) in camels of unknown pregnancy status on pre-established pregnancy and resynchronized fertility, was examined. The camels (n = 201) were divided into two groups after synchronized TB. Control (n = 98) group camels were examined for early pregnancy on Day 21 ±â€¯2 after TB and second mating in nonpregnant camels was done when a dominant follicle of 11-17 mm in diameter was present. Resynch (n = 103) group camels received GnRH treatment on Day 14 ±â€¯2 after TB and PGF2α treatment upon nonpregnancy diagnosis (7 days later) and second mating (resynchronized TB) was done (12 days after GnRH). The pregnancy diagnosis and losses were monitored using ultrasonography. The pregnancy rate on Day 90 (61.2 vs. 59.2%) after TB and pregnancy loss (14.3 vs 11.6%) were similar between control and Resynch groups (P >0.05). There was also no difference in the pregnancy rate (57.1 vs 52.9%) after second mating between the groups (P >0.05). In experiment 2, the reproductive performance following synchronized and resynchronized timed natural services was evaluated in camels under farm (n = 120) and field conditions (n = 214) conditions. Acceptable pregnancy rates were recorded after synchronized TB-1, resynchronized TB-2 and TB-3 under farm and field conditions. After 3 timed services, a cumulative pregnancy rate of 82.5 and 79.7% was recorded under farm and field conditions respectively. In conclusion, the Resynch protocol initiated with GnRH treatment on Day 14 ±â€¯2 after breeding, with unknown pregnancy status, was effective in resynchronizing the follicular wave for subsequent TB, without having any effect on the pre-established pregnancy in dromedary camels.


Assuntos
Camelus , Sincronização do Estro/métodos , Folículo Ovariano/efeitos dos fármacos , Prenhez , Animais , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Gravidez , Distribuição Aleatória
11.
Anim Reprod Sci ; 160: 23-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26164524

RESUMO

This study was conducted to develop a hormone protocol that precisely synchronises follicular development for a timed breeding (TB) programme in dromedary camels. To examine the effect of GnRH treatment at four known stages of follicular development, animals were treated with GnRH when the largest follicle of the wave was 4-7, 8-11, 12-17 and 18-27 mm in diameter. Transrectal ultrasonography was carried out daily up to 20 days after treatment. A hormone protocol (FWsynch) for the synchronisation of follicular wave and TB consisting of GnRH-1 (GnRH) on Day 0, PG-1 (PGF2α) on Day 7, GnRH-2 on Day 10 and PG-2 on Day 17 was initiated at four known stages of follicular development. Ovarian structures were monitored by ultrasonography. The FWsynch protocol was initiated at random stages of follicle development and animals were bred by natural mating at a fixed time at the research facility and in field. The pregnancy was diagnosed by ultrasonography. GnRH treatment in animals with a dominant follicle (DF) of ≥ 11 mm in diameter resulted in synchronous new follicular wave emergence, whereas in animals with a DF ≤ 10 mm, the treatment did not alter the development of the existing follicular wave. The FWsynch protocol was effective in synchronising the follicular wave for TB irrespective of the stage of follicular development at the beginning of the protocol. TB using FWsynch protocol resulted in a pregnancy rate of 60.2% in a research facility and 53.6% and 45.6% in normal and infertile camels respectively under field conditions.


Assuntos
Camelus/fisiologia , Dinoprosta/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Animais , Dinoprosta/administração & dosagem , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Gravidez
12.
Reprod Biol ; 15(3): 188-91, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26370463

RESUMO

The acquisition of ovulatory capacity in the growing dominant follicle (DF) of dromedary camels was examined in the current study. Ovulation occurred in response to hCG (1500 IU) in 27.3%, 58.3% or 100% of camels with follicles of 9, 10 or 11 mm diameter, respectively. A high dose of hCG (4500 IU) resulted in ovulation of 77.8% and 100% of camels with follicles of 9 and 10mm, respectively. In naturally mated animals, ovulation occurred in 36.4% and 92.8% of camels with 10 and 11 mm follicles, respectively.


Assuntos
Camelus/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Gonadotropina Coriônica/farmacologia , Feminino , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Indução da Ovulação/métodos
13.
Theriogenology ; 78(5): 965-73, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819287

RESUMO

Ovarian follicular dynamics was monitored by transrectal ultrasonography, for a period of 60 to 90 days, and its correlation with plasma estradiol-17ß (E2) and progesterone (P4) were studied in seventeen, multiparous, non-lactating, 12 to 20-year-old dromedary camels. The average number of follicles recruited (12.77 ± 0.93) in each wave between animals varied (P < 0.001). The number of follicles recruited during different follicular waves was highly repeatable (0.95) within individual animals. The growth and mature phase periods of the dominant follicle (DF) were 6.10 ± 0.15 and 10.20 ± 0.47 days, respectively with a linear growth rate of 1.17 ± 0.02 mm/day between Day 0 and 10 of the follicular wave. There was an inverse relationship between the diameter of the largest DF and number of follicles (r = -0.95, P < 0.001). The DF development did not regularly alternate between the ovaries and the incidence of codominance was 45%. The mean maximum diameter of DF during its mature phase was 27.30 ± 0.78 mm and oversized follicle was 38.43 ± 1.41 mm. In 73.3% waves, the DF continued its growth for a period of 10.64 ± 1.53 days even after losing its dominance and developed into oversized follicle. The duration of the regression phase of DF and oversized follicle were 24.71 ± 3.79 and 18.50 ± 2.23 days. The mean duration of a complete follicular wave was 47.11 ± 2.94 days with an interwave interval (IWI) of 16.36 ± 0.37 days. The IWI within an individual was repeatable (0.88) and between the animals was variable (P < 0.001). Plasma E2 concentration profiles showed a wave like pattern. The peak plasma E2 concentrations were attained approximately 12 days after beginning of the growth phase, when the largest DF grew to a diameter of 18.7 mm. Plasma concentration of P4 was below 1.0 ng/mL in 85% of waves and above 1.0 ng/mL in 15% of the waves for a period of 3 to 6 days in the absence of spontaneous ovulation. It is concluded that ovarian follicular development and plasma E2 concentrations occurs in a wave like pattern in dromedary camels and the IWI and follicle numbers recruited per wave are variable between the animals and repeatable within an individual animal.


Assuntos
Camelus/fisiologia , Folículo Ovariano/fisiologia , Animais , Estradiol/sangue , Estradiol/metabolismo , Ciclo Estral/fisiologia , Feminino , Progesterona/sangue , Progesterona/metabolismo
14.
Anim Reprod Sci ; 132(3-4): 231-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22727034

RESUMO

The present study was carried out to elucidate the effect of progesterone (P4) from the induced corpus luteum (CL) on the characteristics of the dominant follicle (DF) in dromedary camels (Camelus dromedarius). Ovarian follicular and induced CL dynamics were monitored by transrectal ultrasonography in eight camels during the peak breeding season. The characteristics of the DF were monitored daily from the day of emergence into a wave, until it appeared to lose its dominance and the DF of a subsequent wave grew to a diameter of 13-17 mm. At this stage ovulation was induced by hCG and the DF was monitored every 8 h for 48 h. After ovulation, CL dynamics and follicular development (emergence of a new wave, growth and mature phase of the selected DF) were monitored daily. Blood samples were collected during each ultrasound examination to study the P4 profile in these animals. The CL developed to a maximum size (22.55 ± 3.24 mm) with a peak concentration of P4 (4.60 ± 2.57 ng/ml) 7 days after ovulation. The size of the CL was positively correlated with the P4 concentration (r = 0.612) during the different stages of the CL dynamics. The presence of CL did not affect the linear growth rate, duration of growth and mature phases of the DF. The development of the DF to its maximum size during its mature phase and inter-wave interval were not affected by the P4 secreted by the induced CL. In conclusion, there is no evidence from this study to suggest that P4 from induced CL altered the characteristics of a DF in dromedary camels.


Assuntos
Camelus/fisiologia , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Progesterona/metabolismo , Animais , Corpo Lúteo/metabolismo , Feminino
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