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1.
Vet Clin North Am Equine Pract ; 35(3): 607-642, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31672204

RESUMO

Donkeys are nonseasonal, polyestrous, territorial, and nonharem breeders. Although there are many similarities between horses and donkeys, there are also reproductive features that differ, from the longer cervix in the jenny to spermatogenic efficiency in the jack. Mules display reproductive cyclic activity but are rarely fertile. Frozen donkey semen has high pregnancy rates in mares, but lower rates in jennies. This article reviews key aspects of donkey and mule reproductive physiology, reproductive medicine, and assisted reproductive techniques that are useful for practitioners offering assisted reproductive techniques, and also for practitioners with the occasional client with a basic reproductive question.


Assuntos
Equidae/fisiologia , Reprodução/fisiologia , Técnicas de Reprodução Assistida/veterinária , Animais , Feminino , Cavalos , Masculino , Gravidez
2.
Reprod Domest Anim ; 54 Suppl 3: 38-45, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31512315

RESUMO

The air-liquid interface (ALI) approach is primarily used to mimic respiratory tract epithelia in vitro. It is also known to support excellent differentiation of 3D multilayered skin models. To establish an ALI culture, epithelial cells are seeded into compartmentalized culture systems on porous filter supports or gel substrata. After an initial propagation period, the culture medium is removed from the apical side of the epithelium, exposing the cells to the surrounding air. Therefore, nutritive supply to the cells is warranted only by the basolateral cell pole. Under these conditions, the epithelial cells differentiate and regain full baso-apical polarity. Some types of epithelia even generate in vivo-like apical fluid or mucus. Interestingly, the ALI culture approach has also been shown to support morphological and functional differentiation of epithelial cells that are not normally exposed to ambient air in vivo. This review aims at giving a brief overview on the characteristics of ALI cultures in general and ALI models of female reproductive tract epithelia in particular. We discuss the applicability of ALI models for the investigation of the early embryonic microenvironment and for its implications in assisted reproductive technologies.


Assuntos
Técnicas de Cultura de Células , Genitália Feminina/citologia , Animais , Desenvolvimento Embrionário , Células Epiteliais/citologia , Feminino , Humanos , Modelos Biológicos , Técnicas de Reprodução Assistida/veterinária , Mucosa Respiratória/citologia
3.
Reprod Domest Anim ; 54 Suppl 3: 22-28, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31512320

RESUMO

The biological nature of age-related declines in fertility in males of any species, including stallions, has been elusive. In horses, the economic costs to the breeding industry are frequently extensive. Mitochondrial function in ejaculated sperm, which is essential for sperm motility, is reflected by adenosine triphosphate production, mitochondrial oxidative efficiency and production of reactive oxygen species, and that this balance may become compromised in ageing stallions and during the process of cryopreservation. This presentation will focus on mitochondrial integrity and function as an avenue for understanding the pathophysiology of sperm when undergoing cryopreservation and male ageing. We discuss the importance of understanding the differences and similarities of sperm mitochondria to that of somatic cells regarding structure and mitochondrial biochemistry relating to sperm function. The roles of oxidative phosphorylation and glycolysis in sperm mitochondria are outlined as is the method of determining oxygen consumption and calcium homoeostasis in sperm mitochondria. Further, we outline the role of oxidative stress and reactive oxygen species.


Assuntos
Cavalos/fisiologia , Mitocôndrias/fisiologia , Espermatozoides/fisiologia , Envelhecimento/fisiologia , Animais , Criopreservação/veterinária , Fertilidade/fisiologia , Glicólise , Masculino , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Técnicas de Reprodução Assistida/veterinária , Motilidade Espermática/fisiologia , Espermatozoides/citologia , Espermatozoides/metabolismo
4.
Adv Exp Med Biol ; 1200: 413-463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31471805

RESUMO

Amphibians have experienced a catastrophic decline since the 1980s driven by disease, habitat loss, and impacts of invasive species and face ongoing threats from climate change. About 40% of extant amphibians are under threat of extinction and about 200 species have disappeared completely. Reproductive technologies and biobanking of cryopreserved materials offer technologies that could increase the efficiency and effectiveness of conservation programs involving management of captive breeding and wild populations through reduced costs, better genetic management and reduced risk of species extinctions. However, there are relatively few examples of applications of these technologies in practice in on-the-ground conservation programs, and no example that we know of where genetic diversity has been restored to a threatened amphibian species in captive breeding or in wild populations using cryopreserved genetic material. This gap in the application of technology to conservation programs needs to be addressed if assisted reproductive technologies (ARTs) and biobanking are to realise their potential in amphibian conservation. We review successful technologies including non-invasive gamete collection, IVF and sperm cryopreservation that work well enough to be applied to many current conservation programs. We consider new advances in technology (vitrification and laser warming) of cryopreservation of aquatic embryos of fish and some marine invertebrates that may help us to overcome factors limiting amphibian oocyte and embryo cryopreservation. Finally, we address two case studies that illustrate the urgent need and the opportunity to implement immediately ARTs, cryopreservation and biobanking to amphibian conservation. These are (1) managing the biosecurity (disease risk) of the frogs of New Guinea which are currently free of chytridiomycosis, but are at high risk (2) the Sehuencas water frog of Bolivia, which until recently had only one known surviving male.


Assuntos
Anfíbios , Bancos de Espécimes Biológicos , Conservação dos Recursos Naturais , Técnicas de Reprodução Assistida/veterinária , Animais , Espécies em Perigo de Extinção
5.
Anim Reprod Sci ; 207: 138-145, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31208849

RESUMO

The use of camels for racing, milking and as show animals is growing in popularity, thus there is increased enthusiasm to breed more of the genetically superior animals. This review highlights recent developments in assisted reproductive techniques in camels, such as embryo transfer and artificial insemination, to ensure more rapid genetic progress. This paper discusses the difficulties involved in handling the semen due to its high viscosity and ways to reduce it. It also examines methods for short term liquid storage of fresh semen with and without the use of antioxidants to reduce oxidative stress. The widespread use of AI in camels is hindered by the lack of a reliable method for deep freezing and long term storage but various freezing protocols, cryoprotectants and freezing and thawing methods are discussed as well as different insemination techniques. Embryo transfer requires the donor to be superovulated and the recipients synchronized. This review discusses different protocols used for superovulation of donor animals and the problems involved. It also examines various methods to synchronize recipients, or how to make best use of non-synchronized or non ovulated recipients. Cryopreservation of embryos would greatly improve the wider use of ET and spread of genetics worldwide so methods for slow cooling and new methods of vitrification with promising results are discussed.


Assuntos
Camelus , Técnicas de Reprodução Assistida/veterinária , Animais , Cruzamento/métodos , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Masculino , Gravidez , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária
7.
Anim Reprod Sci ; 207: 171-179, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31227324

RESUMO

Declining fertility in association with declining testicular function is commonly seen as stallions age and can be the cause of significant economic losses in the equine breeding industry. This manuscript describes how to clinically recognize the signs of age-related declining testicular function (testicular degeneration) and also provides mare and stallion management strategies for improving reproductive outcomes. Finally, the current understanding of the pathophysiology of the disease is presented, including the results of recent studies that are beginning to uncover the underlying causes for age-related declines in testicular function in stallions. These new findings provide a basis for possible future treatments that could delay the effects of aging on the testis.


Assuntos
Envelhecimento/fisiologia , Cruzamento , Cavalos/fisiologia , Técnicas de Reprodução Assistida/tendências , Testículo/fisiologia , Animais , Cruzamento/métodos , Feminino , Preservação da Fertilidade/métodos , Preservação da Fertilidade/tendências , Preservação da Fertilidade/veterinária , Masculino , Idade Paterna , Técnicas de Reprodução Assistida/veterinária , Análise do Sêmen/veterinária
8.
Vet Clin North Am Food Anim Pract ; 35(2): 265-276, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31103180

RESUMO

Large offspring syndrome (LOS) is a fetal overgrowth condition in bovines most often observed in offspring conceived with the use of assisted reproductive technologies (ART). Phenotypes observed in LOS include, overgrowth, enlarged tongues, umbilical hernias, muscle and skeleton malformations, abnormal organ growth and placental development. Although LOS cases have only been reported to be associated with ART, fetal overgrowth can occur spontaneously in cattle (S-LOS). S-LOS refers to oversized calves that are born at normal gestation lengths. ART-induced LOS has been characterized as an epigenetic syndrome, more specifically, a loss-of-imprinting condition. We propose that S-LOS is also a loss-of-imprinting condition.


Assuntos
Doenças dos Bovinos/patologia , Transtornos do Crescimento/veterinária , Técnicas de Reprodução Assistida/veterinária , Animais , Síndrome de Beckwith-Wiedemann/genética , Síndrome de Beckwith-Wiedemann/patologia , Síndrome de Beckwith-Wiedemann/veterinária , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/genética , Feminino , Transtornos do Crescimento/genética , Transtornos do Crescimento/patologia , Humanos , Gravidez , Técnicas de Reprodução Assistida/efeitos adversos
9.
Theriogenology ; 132: 36-44, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30986613

RESUMO

Advancing maternal age is known to negatively affect fertility in the horse. This age-related decrease in fertility has been linked primarily to reduced oocyte quality rather than to impaired uterine function. In the past decade, the use of ovum pick-up (OPU) and ICSI to produce foals has rapidly gaining popularity amongst sport horse breeders. However, it is not yet known how maternal age influences the efficiency of a commercial OPU-ICSI program and whether the age effect is similar to that observed for other ART in the horse. To answer this question, reproductive records of 289 mares bred by natural mating (NM), 328 mares bred by AI, 205 embryo donor mares (AI-EF-ET), and 473 mares submitted for OPU-ICSI and ET were analyzed retrospectively using a regression model to investigate the effects of maternal age and breeding technique on the likelihood of producing a viable pregnancy. The reproductive efficiency (quantified as the proportion of mares that yielded at least one Day 45 pregnancy) of the different breeding techniques NM, AI, AI-EF-ET and OPU-ICSI-ET was 63.3, 43.9, 45.8 and 37.4%, respectively (P < 0.05). However, the frequent production of multiple embryos per ICSI session (up to 10 embryos in one attempt), makes OPU-ICSI-ET as effective as AI-EF-ET when measured in terms of the mean number of Day 45 pregnant recipients per donor mare. Increasing maternal age was associated with a reduction (P < 0.05) in the reproductive efficiency of all breeding techniques (NM, AI, AI-EF-ET) except OPU-ICSI-ET (P > 0.05). In the OPU-ICSI-ET group, increasing maternal age was associated with a lower number of follicles aspirated and oocytes recovered per mare. Nevertheless, the percentage of blastocysts per injected oocyte, and post-ET likelihoods of pregnancy and pregnancy loss were not influenced by the age of the oocyte donor mare (P > 0.05).


Assuntos
Envelhecimento , Cavalos , Idade Materna , Técnicas de Reprodução Assistida/veterinária , Animais , Embrião de Mamíferos/fisiologia , Feminino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
10.
Theriogenology ; 129: 154-159, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30851479

RESUMO

The Asiatic black bear (ABB; Ursus thibetanus ussuricus) is a globally endangered species, and measures to help increase their population are necessary. For the successful restoration of this species, artificial breeding as well as conservation translocation are considered important. The aims of the present study were to evaluate the feasibility and effectiveness of urethral catheterization (UC), which is effectively used in feline species, for semen collection from ABBs and establish the optimal protocol for semen collection via this technique. Seven clinically healthy, adult male ABBs (age, 6-13 years; weight, 130-180 kg) housed at the Species Restoration Technology Institute, Korea were included in this study. All study procedures were performed during the breeding season (June to August) over 3 consecutive years. Semen samples were collected once or three times from all bears by ultrasound-guided UC or electroejaculation (EE) under general anesthesia, and their characteristics, including sperm motility, were evaluated. The day of semen collection was defined as Day 0. The semen collected by the UC method was stored at 4 °C, and sperm motility was evaluated at the same time every day for 16 days. The successful collection rates for the UC and EE methods were 92.3% and 53.8%, respectively. The sperm concentration (4718.9 ±â€¯1526.1 vs. 185.0 ±â€¯34.2 × 106/ml), total sperm count (1196.6 ±â€¯955.5 vs. 100.9 ±â€¯70.0 × 106), sperm motility score (4.39 ±â€¯0.78 vs. 3.00 ±â€¯1.73), viability (98.2 ±â€¯2.3 vs. 82.7 ±â€¯19.6), and the proportion of spermatozoa with intact acrosomes (92.2% ±â€¯9.3% vs. 75.6% ±â€¯10.6%) were higher with the UC method than with the EE method, whereas the proportion of spermatozoa with an abnormal morphology (23.1% ±â€¯4.6% vs. 45.6% ±â€¯19.5%) was lower with the former than with the latter. Over the course of cool storage, there was an overall decrease in the total motility, progressive motility, and viability, although viability was >50% until Day 10. These findings suggest that ultrasound-guided UC is a useful and feasible tool for the collection of high-quality semen from ABBs. The collected semen remains viable for up to 10 days, with high sperm motility maintained for up to 7 days, when stored at 4 °C.


Assuntos
Recuperação Espermática/veterinária , Cateterismo Urinário/veterinária , Ursidae , Animais , Cruzamento/métodos , Espécies em Perigo de Extinção , Masculino , Técnicas de Reprodução Assistida/instrumentação , Técnicas de Reprodução Assistida/veterinária , Análise do Sêmen/veterinária , Recuperação Espermática/instrumentação , Cateterismo Urinário/métodos
11.
Theriogenology ; 128: 31-39, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30735916

RESUMO

Heifers have two or three major follicular waves per interovulatory interval (IOI). In mares and women, the ovulatory wave is the only major wave in most (75%) IOI. The beginning of diameter deviation during follicle selection of the future dominant follicle (DF) is followed by continued growth of DF and decreasing growth of the future subordinate follicles. Diameter deviation in Bos taurus heifers, mares, and women begins when the future DF is a mean of 8.5, 22.5, and 10.5 mm, respectively. Selection of the ovulatory follicle occurs more frequently from right ovary (RO) in heifers and women and from left ovary (LO) in nulliparous mares with no difference between ovaries in parous mares. The RO predilection for ovulation is preceded by a predilection for more follicles in RO before the beginning of deviation as indicated by (1) in heifers and women, there were more predeviation follicles in RO than LO and ovulation occurred more frequently from RO whereas in mares there was no difference between ovaries in number of predeviation follicles and ovulation occurred with similar frequency between ovaries and (2) in heifers, the number of ovulatory waves with DF in the ovary that had more predeviation follicles was greater than the number of waves with DF in the ovary that had fewer follicles. In heifers, ovulation from RO occurs more frequently when the regressed CL is also in RO and is attributable to a positive intraovarian effect of the CL on predeviation follicles that were adjacent to the CL. The positive two-way effect between CL and future DF when adjacent is expressed by greater dimensions and vascular perfusion of CL and DF. This phenomenon awaits study in mares and women. An exception to more frequent RO ovulation in heifers occurs in wave 3 owing to a switch during predeviation in future dominance to a smaller follicle when the largest follicle is adjacent to the regressing CL. A preovulatory contralateral relationship (DF and CL in opposite ovaries) during the last wave of an IOI in heifers usually (eg, 88%) converts to an ipsilateral relationship during wave 1 of the next IOI in association with continuity in vascular perfusion and number of predeviation follicles per ovary. Alternating relationships between consecutive ovulations were not found in mares and is controversial in women. Applied potential of ovarian asymmetry is indicated by greater blastocyst rate for RO oocytes in cattle and greater pregnancy rate for RO ovulation in women.


Assuntos
Corpo Lúteo/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Bovinos , Corpo Lúteo/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/sangue , Cavalos , Humanos , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/fisiologia , Técnicas de Reprodução Assistida/veterinária
12.
Theriogenology ; 129: 37-45, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30797138

RESUMO

The porcine industry is of great importance worldwide, and so any technological innovation in one or more of the associated production areas is of interest for meat production. Among such innovations in the reproduction area, post-cervical or intrauterine artificial insemination (PCAI) has emerged as a new approach in artificial insemination (AI). PCAI is gradually replacing traditional cervical insemination (CAI), particularly in countries with intensive pig production industries. This type of insemination, which deposits the semen in the body of the uterus (as opposed to traditional cervical deposition), is increasingly used in the field due to its simplicity and the numerous advantages that it provides at production level (e.g. reduced number of sperm, less time required to perform insemination and faster genetic improvement) and, consequently, from an economic point of view. In addition, since its inception, PCAI has been combined with other reproductive biotechnologies, such as the use of frozen-thawed sperm, fixed-time AI or sperm-mediated gene transfer. However, despite its wide acceptance and application, new approaches for increasing the efficiency of PCAI are constantly being sought, such as the adjustment and standardization in sperm numbers, the conservation of the PCAI semen dose, its association with other biotechnologies (sex-sorted sperm) or its efficacy in young (nulliparous and primiparous) females.


Assuntos
Inseminação Artificial/veterinária , Suínos , Animais , Cruzamento/métodos , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/tendências , Técnicas de Reprodução Assistida/tendências , Técnicas de Reprodução Assistida/veterinária
13.
Theriogenology ; 127: 130-136, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30685688

RESUMO

The objective of the present study was to assess the effects on ovulation and reproductive performance of a single injection of either GnRH or hCG applied 9 days before the start of the seasonal breeding period in anovulatory anoestrus cows compared with a 7-day progesterone-Ovsynch protocol. The study was conducted on four grass-based seasonal calving dairy herds in Ireland. The total number of cows in the herds was 2112, of which 488 were diagnosed as anoestrus based on absence of behavioural oestrus during a 30 day period. Ovarian structures and the uterus were examined by transrectal ultrasound on all 488 presumptive anestrus cows 9 days before mating start date (MSD). The number of corpora lutea (CL), number of large follicles (≥10 mm) and uterine reproductive tract score were recorded. Only cows that had no CL, ultrasound reproductive tract score ≤2 and were ≥30 days in milk (DIM) were enrolled in the study (n = 214). Cows were blocked by parity, DIM and body condition score and randomly assigned to one of four treatments: i.m. injection of gonadotropin releasing hormone analogue [GnRH; (n = 57)], i.m. injection of human chorionic gonadotropin [hCG; (n = 48)], 7-day Progesterone-Ovsynch protocol [P4OV; (n = 60)] and Control (no hormonal intervention, n = 49). A second ultrasound examination was performed 7 days after treatment to determine ovulatory response. There was a treatment effect on ovulation rate (P < 0.0001), whereby Control cows had a lesser ovulation rate compared with GnRH-, hCG- and P4OV-treated cows. Submission rate during the first 21 days of the breeding period [SR21; (P = 0.74)], pregnant to first service [P/AI1; (P = 0.24)], pregnant within 42 days after the onset of breeding [P42; (P = 0.73)], and pregnant within 84 days after the onset of breeding were not affected by treatment. A tendency was observed (P = 0.07) for greater likelihood of pregnancy within 21 days after the onset of breeding (P21) for P4OV and Control cows compared with GnRH- and hCG-treated cows. GnRH- and hCG-treated cows tended (P = 0.10) to have greater P/AI1 when first service events occurred after day 21 of the breeding period compared with Control cows. P4OV cows had shorter MSD to first service interval (P = 0.0001) and shorter MSD to conception interval (P = 0.02) compared with Control, GnRH- and hCG-treated cows. In conclusion, treatment of anestrous cows with GnRH or hCG resulted in an increase in ovulation rate compared with untreated Control cows, but did not improve reproductive performance during the first 21 days of the breeding season. The best reproductive performance results were obtained with the P4OV treatment, but this treatment has the greatest cost, and has the greatest number of interventions. The observation of good P/AI1 in hCG- and GnRH- treated cows when the first insemination occurred later than day 21 after MSD warrants further investigation, and suggests that these interventions should be applied earlier than 9 days before the farm MSD.


Assuntos
Anestro , Técnicas de Reprodução Assistida/veterinária , Animais , Cruzamento , Bovinos , Gonadotropina Coriônica/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Ovulação/efeitos dos fármacos , Projetos Piloto , Distribuição Aleatória , Reprodução , Estações do Ano , Útero/diagnóstico por imagem
14.
Trop Anim Health Prod ; 51(2): 473-475, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30121756

RESUMO

We hypothesised that use of reproductive technologies (RTs) would result in increases in economic and genetic gains of a dairy cattle breeding programme. A deterministic approach was used to compare RTs that can be utilised to increase dairy cattle productivity and profitability in Kenya. These were artificial insemination (AI), embryo transfer (ET) using old (ETOB) and young (ETYB) bulls and in vitro fertilisation (IVF). Natural mating (NAm) was assumed to be the standard reproduction practice in Kenya against which the genetic and economic efficiencies of the RTs were compared. A three tiers open nucleus system was assumed to describe the dairy cattle breeding programme in Kenya. It was open to use of imported semen in the nucleus. The nucleus was assumed to be closed to upward movement of live animals. This is the common practice in Kenya where large farms act as the nucleus from which the multipliers (medium-sized farms) buy replacement stock and subsequently sell replacement animals to the commercial sector (smallholder farms). The increase in monetary gain ranged between 11% when AI was used and 184% when utilising either juvenile ET or IVF. The ETYB and IVF resulted in similar economic and genetic responses for all comparison criteria. The generation interval reduced by between 0.8% in AI and 47% in ETYB and IVF technologies. The respective milk yield (MY) and daily weight gain (dWG) responses were between 25 to 150% and 0 to 110% for the AI and ETYB and IVF.


Assuntos
Cruzamento/métodos , Bovinos/genética , Técnicas de Reprodução Assistida/veterinária , Animais , Cruzamento/economia , Indústria de Laticínios/métodos , Transferência Embrionária , Fazendas , Feminino , Inseminação Artificial/veterinária , Quênia , Masculino , Leite , Modelos Teóricos , Reprodução , Técnicas de Reprodução Assistida/economia , Sêmen
15.
Theriogenology ; 126: 68-74, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30530160

RESUMO

The aim of this study was to evaluate the pattern of expression of LHCGR isoforms in Gir heifers characterized as good (10.3 ±â€¯1.2 ova/embryos per flush, n = 5) or poor responders (1.1 ±â€¯0.3 ova/embryos per flush, n = 5) to superovulation protocols. In both groups, an adapted ultrasound-guided follicular aspiration system was used to collect granulosa cells from 8 mm follicles formed either during a synchronized, non-stimulated follicular wave (no stimulation control, NS) or on the fourth day of a superovulation protocol (SOV) induced with 200 IU of pFSH. The recovered follicular fluid was centrifuged and granulosa cells were washed with NaCl 0.9% and kept in RNAlater®. RNA extraction was performed using a commercial RNeasy Micro Kit and eluted samples were quantified and reverse transcribed using the commercial Superscript III kit. cDNA samples were amplified by real-time PCR using a primer to target LH/hCG receptor gene - not selective for LHCGR isoforms (total LHCGR) - and four sets of isoforms selective primers (S1, S10, S10 + 11, and S11). Analyses were performed using the REST software and expression levels are shown as mean ± SEM. Under physiological conditions (NS), poor responders had a higher expression of total LHCGR (4.9 ± 1.7 fold-change, P < 0.01) as well as isoforms S10, S11 and S10 + 11, compared to good responders. In both phenotypes, superovulation down-regulated total LHCGR expression (-0.5 ± 0.2 and -0.9 ± 0.0 for good and poor responders, respectively; P < 0.05). However, in poor responders the exogenous FSH treatment up-regulated the S10 (2.4 ± 2.0; P < 0.05), S10 + 11 (3.8 ± 3.2; P < 0.01), and S1 isoforms (1.8 ± 1.3; P < 0.05), compared to good responders We conclude that down-regulation of total LHCGR, associated to up-regulation of their inactive isoforms, may have compromised follicle development and thus contributed to the low efficiency of superovulation in heifers with a poor responder phenotype.


Assuntos
Bovinos/fisiologia , Indução da Ovulação/veterinária , Receptores do LH/metabolismo , Técnicas de Reprodução Assistida/veterinária , Superovulação/genética , Animais , Bovinos/metabolismo , Sincronização do Estro , Feminino , Células da Granulosa/metabolismo , Indução da Ovulação/métodos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores do LH/genética
16.
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
17.
Theriogenology ; 126: 36-40, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30513402

RESUMO

Equine embryos tolerate an unusually large degree of negative uterine asynchrony (recipient mare up to 5 days behind the donor mare). By contrast, positive asynchrony of more than 2 days results in a high incidence of early embryonic loss (EEL). Day 8 embryos range in diameter from approximately 130-1300 µm, with embryos smaller than 300 µm reported to suffer an increased incidence of EEL. However, it is not known whether this reduced viability is due to intrinsically poor embryo quality, or to inadvertent recipient uterine stage-embryo (positive) asynchrony. To examine whether small embryos survive better in Day 4-5 recipients than in recipients with a more advanced uterine stage, the likelihood of pregnancy (PR) and EEL for 62 small (<300 µm) and 215 larger Day 8 horse embryos were compared after transfer to recipients at different uterine stages (Days 4-5, 6-7 and 8-9) using logistic regression. Overall, EEL was higher (21.2%; P < 0.05) for small than larger embryos (7.1%). However, neither PR nor EEL were influenced by the recipient's uterine stage at the time of transfer (P > 0.1). The EEL for small embryos transferred into Day 4-5, 6-7 and 8-9 recipients was 20.8, 18.7 and 25.0%, respectively. We conclude that embryos recovered on Day 8 with a diameter <300 µm are at increased risk of EEL due to reasons other than inadvertent positive asynchrony with the recipient mare's uterus.


Assuntos
Desenvolvimento Embrionário , Cavalos/embriologia , Técnicas de Reprodução Assistida/veterinária , Animais , Tamanho Celular , Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Sincronização do Estro , Feminino , Modelos Logísticos , Útero/fisiologia
18.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 56(1): e143588, jun. 2019. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1005017

RESUMO

The introduction of new strains of mice in specific pathogen-free (SPF) animal facilities should be performed carefully to avoid breaking sanitary barriers. To meet this need, animals should be rederived to reduce infection risk and thus avoid research interference caused by loss of animal health status and welfare. The objective of this study was to implement mice embryo transfer in the laboratory mouse facility of the Department of Immunology at the Institute of Biomedical Sciences/University of São Paulo, Brazil. Embryo transfers were performed to rederive genetically modified mouse strains with undefined sanitary status, received from different research and educational institutions. Fertilized eggs at two-cell stage were obtained by natural means and transferred into the oviducts of SPF pseudo-pregnant female mice. All surgical procedures were performed under aseptic conditions. A total of 625 embryos were transferred into the recipients. 148 pups were born, of which 140 were reared. Viruses, bacteria and intestinal protozoa were eliminated using this technique. The improvement in the microbiological status of mice allowed their expansion in our SPF facility. With these results, we can stimulate the use of embryo transfer technique between rodent facilities in Brazil and thus encourage the distribution of better models to our scientific community.(AU)


A introdução de novas linhagens de camundongos em biotérios livres de patógenos específicos (SPF) deve ser realizada com critérios para evitar a quebra das barreiras sanitárias. Dessa forma, os animais devem ser rederivados para reduzir os riscos de infecção e evitar as interferências provocadas pela perda do status sanitário e do bem-estar dos animais. O objetivo deste estudo foi implementar a transferência de embriões murinos no Biotério do Departamento de Imunologia do Instituto de Ciências Biomédicas da Universidade de São Paulo, Brasil. As transferências embrionárias foram realizadas para rederivar linhagens de camundongos geneticamente modificadas com status sanitário não conhecido, recebidas de diferentes instituições de pesquisa e de ensino. Os embriões em duas células foram obtidos pelos métodos naturais e transferidos para os ovidutos de fêmeas de camundongos SPF pseudoprenhas. Todos os procedimentos cirúrgicos foram realizados sob condições assépticas. Um total de 625 embriões foram transferidos para as receptoras. Foram obtidos 148 filhotes nascidos vivos, destes 140 foram desmamados. Por meio desta técnica, foram eliminados vírus, bactérias e protozoários intestinais. A melhora no status microbiológico dos camundongos permitiu a expansão destes em nossa colônia SPF. Com esses resultados, podemos promover o uso da técnica de transferência de embriões entre os biotérios brasileiros e assim incentivar a distribuição de modelos mais adequados para a nossa comunidade científica.(AU)


Assuntos
Animais , Ratos , Técnicos em Manejo de Animais , Técnicas de Reprodução Assistida/veterinária , Transferência Embrionária/veterinária , Camundongos/genética
19.
Pesqui. vet. bras ; 38(12): 2284-2288, dez. 2018. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976428

RESUMO

The efficiency of a culture system is related to the elaboration and replacement of a medium with conditions suitable for follicular development. Recent investigations suggested that in vitro culture medium should be replaced after specific time periods in various species. However, the suitable interval for the exchange of in vitro culture medium has not yet been established in equine species. The objective of this investigation was to evaluate the effect of medium exchange intervals of 24 hours (T24) or 48 hours (T48) for in vitro culture of preantral follicles at 2 or 6 days. At the end of the culture period, the fragments were processed using classical histology. Equine preantral follicles were classified according to morphological integrity and developmental stage. Data analysis was performed using Fisher's test with a significance level of p<0.05. Out of a total of 399 follicles evaluated, 174 (43.6%) were primordial follicles, 225 (56.4%) were in development, and 63.76% were morphologically intact. In the in vitro culture performed over two days, there was no significant difference in relation to follicular integrity after medium replacement (p>0.05). Compared to the medium replacement at six days of culture, there was a statistically significant difference for T24 (68.9%, p<0.05). Therefore, we suggest changing the medium for equine species at 48 hours after the start of culture followed by subsequent daily replacements.(AU)


A eficiência de um sistema de cultivo está relacionada à elaboração e substituição do meio de cultivo com condições adequadas ao desenvolvimento folicular. Pesquisas recentes sugerem que o meio de cultivo in vitro deve ser substituído após períodos de tempo específicos para várias espécies. No entanto, o intervalo adequado para a troca de meio de cultivo in vitro ainda não foi estabelecido na espécie equina. O objetivo desta investigação foi avaliar o efeito de intervalos de troca média de 24 horas (T24) ou 48 horas (T48) para cultivo de folículos pré-antrais aos 2 ou 6 dias. No final do período de cultivo, os fragmentos foram processados ​​usando histologia clássica. Os folículos pré-antrais equinos foram classificados de acordo com a integridade morfológica e o estágio de desenvolvimento. A análise dos dados foi realizada utilizando o teste de Fisher com um nível de significância de p<0,05. De um total de 399 folículos avaliados, 174 (43,6%) foram folículos primordiais, 225 (56,4%) estavam em desenvolvimento e 63,76% estavam morfologicamente intactos. No cultivo in vitro realizado ao longo de dois dias, não houve diferença significativa em relação à integridade folicular após a substituição do meio (p>0,05). Comparado com a substituição média aos seis dias de cultivo, houve diferença estatisticamente significativa para T24 (68,9%, p<0,05). Portanto, sugerimos alterar o meio para as espécies equinas às 48 horas após o início da cultura, seguindo as subsequentes substituições diárias.(AU)


Assuntos
Animais , Feminino , Técnicas de Reprodução Assistida/veterinária , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , Cavalos/anatomia & histologia , Cavalos/embriologia , Cavalos/fisiologia
20.
Theriogenology ; 121: 188-195, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30172130

RESUMO

The objective of the current study was to investigate the effect of subluteal progesterone environment on the efficacy of the ovarian responses in goats passively immunized against endogenous inhibin. Twelve cycling female Shiba goats were synchronized using two doses of prostaglandin F2α 11 days apart. After detection of ovulation (D0, by ultrasonography), goats were randomly assigned into 2 groups: (1) Subluteal P4 group (SLP; n = 6), treated with a previously once-used controlled intravaginal progesterone-releasing device (ou-CIDR) intravaginal from D 6 to D 12 concurrently with a luteolytic dose of PGF2α at D6 (2) Normal Luteal P4 group (NLP; n = 6), had neither ou-CIDR nor PGF2α. In both groups, goats were treated with an intravenous injection of 10 ml of inhibin antiserum at D10. After that, another luteolytic dose of PGF2α was administrated to goats in both groups at D12, and withdrawal of ou-CIDR in the SLP group. Detection of estrous behavior was checked again 24 h following PGF2α administration and or ou-CIDR withdrawal at 8 h intervals with a teaser buck. The follicle populations ≥4 mm in each goat were monitored through transrectal ultrasonography daily from 1 day after inhibin antiserum administration (0 h) and continued until ovulation had been detected (disappearance of large dominant follicles by ultrasonography). In addition, a repeated ultrasonographic scanning was performed 7 days after ovulation, and the ovulation rate had been estimated by counting the number of observed corpora lutea by ultrasonography. Blood samples were collected for measurement of plasma circulating inhibin binding activity, FSH, LH, estradiol (E2), and progesterone (P4) in both groups. Results revealed significant increases in maximum diameter of the preovulatory follicles (5.92 ±â€¯0.17 mm vs 5.31 ±â€¯0.26 mm; P < 0.05), and the mean maximum number of follicles ≥ 4 mm in diameter (18.45 ±â€¯3.40 vs 12.15 ±â€¯6.21; P < 0.05) in the SLP group compared with that of the NPL group. No significant differences were observed between both groups in term of inhibin binding activity %, and FSH. Following immunization, significant increases in the concentrations of circulating LH (at 72 h) and E2 (from 48 to 84 h) were noted in the SLP group as compared with the values obtained from the goats in the NLP group. Moreover, significant increases in ovulation rate (13.85 ±â€¯1.40 vs 5.67 ±â€¯2.10; P < 0.01) and subsequent P4 concentrations (from 192 to 288 h) were found in the SLP group as against those of the NLP group. In conclusion, maintaining a subluteal P4 environment concurrently with passive immunization against endogenous inhibin may improve the superovulatory response in female Shiba goats.


Assuntos
Cabras/fisiologia , Inibinas/imunologia , Indução da Ovulação/veterinária , Técnicas de Reprodução Assistida/veterinária , Animais , Ciclo Estral/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/sangue , Imunização Passiva/veterinária , Hormônio Luteinizante/sangue , Indução da Ovulação/métodos
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