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1.
Genes (Basel) ; 13(5)2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35627154

RESUMO

The corpus luteum (CL) is a temporary endocrine gland that plays a decisive role in the reproductive physiology of gilts. Recently, it has been suggested that exogenous factors may compromise the normal functioning of the CL. In the present study, we aimed to understand to what extent an acute and systemic challenge with lipopolysaccharide (LPS) on the day of estrus could compromise gene expression of gilts' CLs housed in different welfare conditions. For this, we housed 42 gilts in three different housing systems: crates, indoor group pens, and outdoor housing. Then, we challenged six females from each group with LPS and eight with saline (SAL) on the day of estrus. After slaughtering the gilts on the fifth day after the challenge, ovaries were collected for gene expression analysis by RT-qPCR. Housing system and LPS challenge did not have a significant interaction for any genes evaluated; thus, their effects were studied separately. We identified significant (p < 0.05) downregulation of the angiogenic genes VEGF and FTL1 among LPS-challenged animals. Meanwhile, we also observed upregulation of HSD3B1 gene among LPS-challenged animals. We found that STAR and LHCGR genes were differentially expressed depending on the housing system, which indicates that the environment may affect adaptation capabilities. Our results indicate that an acute health challenge on the estrus day alters CL gene expression; however, the role of the housing system remains uncertain.


Assuntos
Qualidade Habitacional , Lipopolissacarídeos , Animais , Corpo Lúteo/metabolismo , Estro/genética , Feminino , Expressão Gênica , Sus scrofa , Suínos/genética
2.
Trop Anim Health Prod ; 53(2): 328, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34002300

RESUMO

The growth and differentiation factor 9 (GDF9) intervenes in the fecundity and prolificacy of the ewe, which are important variables that participate in the reproductive efficiency of a flock. The objective of this study was to evaluate the influence of FecGE mutation of the gene GDF9 in the natural response of the manifestation to estrus, return to estrus, ovulation rate, pregnancy, lambing, prolificacy, and fecundity rate in Pelibuey ewes, during the anestrus period. The sequences of the exon 2 of the gene GDF9 were obtained from blood samples collected in Whatman™ FTA™ cards from 42 multiparous Pelibuey ewes with reproductive records. For this purpose, the quality of the sequences was analyzed and the polymorphisms and genotypes were searched for. The ewes were grouped according to their group: (a) homozygous or Embrapa (GG), (b) wild (AA), and (c) group without gene (sG). All the ewes studied manifested estrus behavior, but none showed signs of return to estrus after natural mating (p > 0.05); likewise, the pregnancy and lambing rates (p > 0.05) did not show differences between groups. However, the group GG presented higher ovulation rate, prolificacy, and fecundity rate (p < 0.05), compared to groups AA and sG. Although no differences were found in the manifestation of estrus, return to estrus, and percentage of pregnancy and lambing in females from the genotypes studied, the homozygous ewes GG presented 1.22 and 1.72 more corpus luteum (CL, p < 0.05), prolificacy of 0.7 and 0.7, and fecundity rate of 0.8 and 1.0 more lambs per ewe (p < 0.05) than the ones produced by the wild-type AA and sG groups, respectively.


Assuntos
Anestro , Fator 9 de Diferenciação de Crescimento/genética , Reprodução , Animais , Estro/genética , Feminino , Mutação , Gravidez , Reprodução/genética , Ovinos/genética , Carneiro Doméstico/genética
3.
Sci Rep ; 9(1): 8354, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175317

RESUMO

In cattle, conceptus development after elongation relies on well-characterized, paracrine interactions with the hosting maternal reproductive tract. However, it was unrecognized previously that the pre-hatching, pre-implantation bovine embryo also engages in biochemical signalling with the maternal uterus. Our recent work showed that the embryo modified the endometrial transcriptome in vivo. Here, we hypothesized that the embryo modulates the biochemical composition of the uterine luminal fluid (ULF) in the most cranial portion of the uterine horn ipsilateral to the corpus luteum. Endometrial samples and ULF were collected post-mortem from sham-inseminated cows and from cows inseminated and detected pregnant 7 days after oestrus. We used quantitative mass spectrometry to demonstrate that the pre-hatching embryo changes ULF composition in vivo. Embryo-induced modulation included an increase in concentrations of lipoxygenase-derived metabolites [12(S)-HETE, 15(S)-HETE] and a decrease in the concentrations of amino acids (glycine), biogenic amines (sarcosine), acylcarnitines and phospholipids. The changed composition of the ULF could be due to secretion or depletion of specific molecules, executed by either the embryo or the endometrium, but initiated by signals coming from the embryo. This study provides the basis for further understanding embryo-initiated modulation of the uterine milieu. Early embryonic signalling may be necessary to guarantee optimal development and successful establishment of pregnancy in cattle.


Assuntos
Blastocisto/metabolismo , Implantação do Embrião/genética , Desenvolvimento Embrionário/genética , Transcriptoma/genética , Aminoácidos/genética , Animais , Blastocisto/fisiologia , Bovinos , Corpo Lúteo/metabolismo , Implantação do Embrião/fisiologia , Endométrio/crescimento & desenvolvimento , Endométrio/metabolismo , Estro/genética , Estro/fisiologia , Feminino , Parto/genética , Parto/fisiologia , Gravidez , Prenhez , Útero/crescimento & desenvolvimento , Útero/metabolismo
4.
Electron. j. biotechnol ; Electron. j. biotechnol;32: 35-40, Mar. 2018. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1022620

RESUMO

Background: Poor reproductive efficiency of river buffalos hampers the production capabilities of animals. Buffalos are mainly considered poor breeders owing to the constrained expression of estrus behavior. Failure to display heat signs is an indication of improper functionality of signaling peptides to trigger on a series of behavioral changes, which can be detectable by breeders for timely insemination of females. This might cause an animal to be a repeat breeder. Genomic variations underlying synthesis of signaling peptides can be a useful marker to select superior animals with better reproductive efficiency. In this context, the current study was designed to analyze the CYP19A1 gene in Nili-Ravi buffalo. Results: A total of 97 animals were selected and were divided into two groups on the basis of their heat score. PCR amplification and sequencing of the amplicons were performed using the specific sets of primer, and then, sequences were analyzed for novel variants. A total of 11 polymorphic sites were identified illustrating phenotypic variation in the heat score. Most of the loci were found homologous. Single Nucleotide Polymorphisms (SNPs) were analyzed for association with silent estrus. A three-dimensional protein model was also generated to locate the position of exonic SNPs. Conclusion: This study illustrated that polymorphic sites in the CYP19A1 gene provided potential markers for selection of buffalos with better estrus behavior.


Assuntos
Animais , Feminino , Gravidez , Estro/genética , Búfalos/genética , Aromatase/genética , Sistema Enzimático do Citocromo P-450/genética , Paquistão , Seleção Genética , Cruzamento , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Peptídeos e Proteínas de Sinalização Intracelular , Inseminação
5.
Genet Mol Res ; 15(1)2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26909900

RESUMO

Frizzled 3 is an important receptor in the Wnt/ß-catenin pathway, a conserved signaling pathway that regulates gene expression and controls diverse developmental processes. However, the role of this protein during follicular development in the adult ovary is not known. The present study was designed to investigate the expression and localization of Frizzled 3 mRNA and protein during the estrous cycle in the mouse ovary through in situ hybridization (ISH), real-time quantitative polymerase chain reaction, immunohistochemistry and western blot. ISH results showed that in proestrus, high expression of Frizzled 3 was found in the granulosa and stroma with weak levels in the corpus luteum. In estrus and diestrus, the stroma had high Frizzled 3 expression, but levels were low in granulosa cells and corpus luteum. In the metestrus, moderate expression of Frizzled 3 was found in the stroma but low to no expression was found in luteal cells and follicles. The mRNA and protein levels of Frizzled 3 were found to be the highest in proestrus and diestrus compared to estrus and metestrus (P < 0.05), confirming the ISH results. During estrus and diestrus, high Frizzled 3 expression was observed in the stroma and moderate levels in granulosa cells, and during estrus and proestrus, low expression was seen in the oocyte cell membrane. The western blot results further confirmed this change during the estrous cycle. Together, these results indicate that Frizzled 3 is involved in regulating follicular development and oocyte maturation during the estrous cycle.


Assuntos
Corpo Lúteo/metabolismo , Receptores Frizzled/genética , Regulação da Expressão Gênica no Desenvolvimento , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Animais , Corpo Lúteo/crescimento & desenvolvimento , Corpo Lúteo/ultraestrutura , Diestro/genética , Estro/genética , Feminino , Receptores Frizzled/metabolismo , Hibridização In Situ , Camundongos , Camundongos Endogâmicos ICR , Oócitos/crescimento & desenvolvimento , Oócitos/ultraestrutura , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/ultraestrutura , Proestro/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
6.
Mol Hum Reprod ; 22(4): 240-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26786179

RESUMO

STUDY HYPOTHESIS: We hypothesize that fertility disorders in patients with aberrant expression of Cysteine-RIch Secretory Protein 2 (CRISP2) could be linked to the proposed functional role of this protein in fertilization. STUDY FINDING: Our in vivo and in vitro observations reveal that Crisp2-knockout mice exhibit significant defects in fertility-associated parameters under demanding conditions, as well as deficiencies in sperm fertilizing ability, hyperactivation development and intracellular Ca(2+) regulation. WHAT IS KNOWN ALREADY: Testicular CRISP2 is present in mature sperm and has been proposed to participate in gamete fusion in both humans and rodents. Interestingly, evidence in humans shows that aberrant expression of CRISP2 is associated with male infertility. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: A mouse line carrying a deletion in the sixth exon of the Crisp2 gene was generated. The analyses of the reproductive phenotype of Crisp2(-/-) adult males included the evaluation of their fertility before and after being subjected to unilateral vasectomy, in vivo fertilization rates obtained after mating with either estrus or superovulated females, in vitro sperm fertilizing ability and different sperm functional parameters associated with capacitation such as tyrosine phosphorylation (by western blot), acrosome reaction (by Coomassie Blue staining), hyperactivation (by computer-assisted sperm analysis) and intracellular Ca(2+) levels (by flow cytometry). MAIN RESULTS AND THE ROLE OF CHANCE: Crisp2(-/-) males presented normal fertility and in vivo fertilization rates when mated with estrus females. However, the mutant mice showed clear defects in those reproductive parameters compared with controls under more demanding conditions, i.e. when subjected to unilateral vasectomy to reduce the number of ejaculated sperm (n = 5; P< 0.05), or when mated with hormone-treated females containing a high number of eggs in the ampulla (n ≥ 5; P< 0.01). In vitro fertilization studies revealed that Crisp2(-/-) sperm exhibited deficiencies to penetrate the egg vestments (i.e. cumulus oophorus and zona pellucida) and to fuse with the egg (n ≥ 6; P< 0.01). Consistent with this, Crisp2-null sperm showed lower levels of hyperactivation (n = 7; P< 0.05), a vigorous motility required for penetration of the egg coats, as well as a dysregulation in intracellular Ca(2+) levels associated with capacitation (n = 5; P< 0.001). LIMITATIONS, REASONS FOR CAUTION: The analysis of the possible mechanisms involved in fertility disorders in men with abnormal expression of CRISP2 was carried out in Crisp2 knockout mice due to the ethical and technical problems inherent to the use of human gametes for fertilization studies. WIDER IMPLICATIONS OF THE FINDINGS: Our findings in mice showing that Crisp2(-/-) males exhibit fertility and fertilization defects under demanding conditions support fertilization defects in sperm as a mechanism underlying infertility in men with aberrant expression of CRISP2. Moreover, our observations in mice resemble the situation in humans where fertility disorders can or cannot be detected depending on the accumulation of own individual defects or the fertility status of the partner. Finally, the fact that reproductive defects in mice are masked by conventional mating highlights the need of using different experimental approaches to analyze male fertility. STUDY FUNDING AND COMPETING INTERESTS: This study was supported by the World Health Organization (H9/TSA/037), the National Research Council of Argentina (PIP 2009-290), the National Agency for Scientific and Technological Promotion of Argentina (PICT 2011, 2023) and the Rene Baron Foundation to P.S.C. and by the MEXT of Japan to M.I. The authors declare that there are no conflicts of interest.


Assuntos
Sequência de Bases , Glicoproteínas/genética , Infertilidade Masculina/genética , Deleção de Sequência , Interações Espermatozoide-Óvulo/genética , Espermatozoides/metabolismo , Adulto , Animais , Cálcio/metabolismo , Moléculas de Adesão Celular , Estro/genética , Éxons , Feminino , Expressão Gênica , Glicoproteínas/deficiência , Humanos , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/cirurgia , Tamanho da Ninhada de Vivíparos , Masculino , Proteínas de Membrana , Camundongos , Camundongos Knockout , Capacitação Espermática/genética , Espermatozoides/patologia , Vasectomia , Zona Pelúcida/metabolismo
7.
Genet Mol Res ; 14(4): 18743-52, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782524

RESUMO

Although RNA-Seq is an effective method for identifying and exploring novel functional genes in mammals, it has rarely been applied to study fertility-related genes in the goat. In this study, RNA-Seq was used to screen the estrus ovaries of uniparous and multiparous Anhui white goats (AWGs). In total, 15,890 genes were identified and 2201 of these were found to be differentially expressed between the genetic libraries from uniparous and multiparous goats. Compared to the uniparous library, 1583 genes were up-regulated and 618 genes were down-regulated in the multiparous library. The FER1L4 gene showed the level of highest up-regulation in the multiparous library, while SRD5A2 expression showed the greatest down-regulation. In order to determine the functions of FER1L4 and SRD5A2 in goats, the expression profiles of the two genes in different tissues from AWGs and Boer goats at diestrus were analyzed by quantitative PCR. FER1L4 and SRD5A2 showed tissue specific expression patterns and were highly expressed in ovaries from both AWGs and Boer goats. FER1L4 was more highly expressed in ovaries from multiparous than uniparous AWGs. In contrast, SRD5A2 was expressed at a lower level in multiparous AWGs. These results indicated that FER1L4 and SRD5A2 may be associated with the high fecundity of AWGs.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Proteínas de Ligação ao Cálcio/genética , Fertilidade/genética , Cabras/genética , Paridade/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Estro/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Biblioteca Gênica , Masculino , Especificidade de Órgãos , Ovário/metabolismo , Gravidez
8.
Anim Reprod Sci ; 151(3-4): 169-81, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25465360

RESUMO

The objective of this study was to compare expression of estrogen receptor alpha (ER-α), ß (ER-ß), progesterone receptor (PR), as well as prostaglandin E2 type 2 (EP2) and 4 (EP4) receptors in the equine myometrium and endometrium during estrus, diestrus and early pregnancy. Tissues were collected during estrus, diestrus, and early pregnancy. Transcripts for ER-α (ESR1), ER-ß (ESR2), PR (PGR), EP2 (PTGER2) and EP4 (PTGER4) were quantified by qPCR. Immunohistochemistry was used to localize ER-α, ER-ß, PR, EP2 and EP4. Differences in transcript in endometrium and myometrium were compared by the ΔΔCT method. Expression for ESR1 (P<0.05) tended to be higher during estrus than diestrus in the endometrium (P=0.1) and myometrium (P=0.06). In addition, ESR1 expression was greater during estrus than pregnancy (P<0.05) in the endometrium and tended to be higher in estrus compared to pregnancy in the myometrium (P=0.1). Expression for PGR was greater (P<0.05) in the endometrium during estrus and diestrus than during pregnancy. In the myometrium, PGR expression was greater in estrus than pregnancy (P=0.05) and tended to be higher during diestrus in relation to pregnancy (P=0.07). There were no differences among reproductive stages in ESR2, PTGER2 and PTGER4 mRNA expression (P>0.05). Immunolabeling in the endometrium appeared to be more intense for ER-α during estrus than diestrus and pregnancy. In addition, immunostaining for PR during pregnancy appeared to be more intense in the stroma and less intense in glands and epithelium compared to estrus and diestrus. EP2 immunoreactivity appeared to be more intense during early pregnancy in both endometrium and myometrium, whereas weak immunolabeling for EP4 was noted across reproductive stages. This study demonstrates differential regulation of estrogen receptor (ER) and PR in the myometrium and endometrium during the reproductive cycle and pregnancy as well as abundant protein expression of EP2 in the endometrium and myometrium during early pregnancy in mares.


Assuntos
Endométrio/metabolismo , Ciclo Estral , Cavalos , Miométrio/metabolismo , Prenhez , Receptores de Prostaglandina E/genética , Receptores de Esteroides/genética , Animais , Diestro/genética , Diestro/metabolismo , Ciclo Estral/genética , Ciclo Estral/metabolismo , Estro/genética , Estro/metabolismo , Feminino , Idade Gestacional , Hormônios Esteroides Gonadais/metabolismo , Cavalos/genética , Cavalos/metabolismo , Ovário/metabolismo , Gravidez , Prenhez/genética , Prenhez/metabolismo , Receptores de Prostaglandina E/metabolismo , Receptores de Esteroides/metabolismo
9.
Anim. Reprod. ; 10(3): 148-159, 2013.
Artigo em Inglês | VETINDEX | ID: vti-8119

RESUMO

This review summarizes those methods - established and emerging of semen assessment whose outcom e intents revealing its potential fertility and, as a carry over concept, that of the sire whose semen we examined. The review does not, however, focus on the wide display of current techn iques designed to explore specific or multiple sets of sperm attributes essential for fertilization but on two basic con cerns present: the heterogeneity of the sperm suspension and the multitude of attributes required for each spermatozoon to be fertile; concepts that shadow our diagnostic capabilities. The review points out advancements in the exploration of the genome, the transcriptome, and the proteome of both spermatozoa and the seminal plasma which unveil how spermatozoa modulate their own survival an d signal to the environment when displaying degenerative changes. Specific seminal plasma components, both among individuals and portions of the ejaculate, not only relate to survival but also signal differential immune tolerance by the female with a previ ously unattended linkage to fertility. Lastly it foresees how Cytomics, combining novel designed motility analyzers, flow cytometers and enhanced digital imaging shall dominate the landscape of andrological laboratories and enable quick determinations on huge sperm numbers for markers highly relevant to sperm function and hence, for fertility.(AU)


Assuntos
Animais , Análise do Sêmen/veterinária , Estro/genética , Espermatozoides/citologia , Bovinos/fisiologia
10.
Anim. Reprod. (Online) ; 10(3): 148-159, 2013.
Artigo em Inglês | VETINDEX | ID: biblio-1461059

RESUMO

This review summarizes those methods - established and emerging of semen assessment whose outcom e intents revealing its potential fertility and, as a carry over concept, that of the sire whose semen we examined. The review does not, however, focus on the wide display of current techn iques designed to explore specific or multiple sets of sperm attributes essential for fertilization but on two basic con cerns present: the heterogeneity of the sperm suspension and the multitude of attributes required for each spermatozoon to be fertile; concepts that shadow our diagnostic capabilities. The review points out advancements in the exploration of the genome, the transcriptome, and the proteome of both spermatozoa and the seminal plasma which unveil how spermatozoa modulate their own survival an d signal to the environment when displaying degenerative changes. Specific seminal plasma components, both among individuals and portions of the ejaculate, not only relate to survival but also signal differential immune tolerance by the female with a previ ously unattended linkage to fertility. Lastly it foresees how Cytomics, combining novel designed motility analyzers, flow cytometers and enhanced digital imaging shall dominate the landscape of andrological laboratories and enable quick determinations on huge sperm numbers for markers highly relevant to sperm function and hence, for fertility.


Assuntos
Animais , Análise do Sêmen/veterinária , Espermatozoides/citologia , Estro/genética , Bovinos/fisiologia
11.
Reproduction ; 143(2): 183-93, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22080140

RESUMO

Oestradiol (E(2)) is a key hormone in the regulation of reproductive processes. The aims of this work were a) to examine the distributions of oestrogen receptor α (ERα) and ERß in the neurons of the superior mesenteric ganglion (SMG) in the oestrus stage by immunohistochemistry, b) to demonstrate whether E(2) in the SMG modifies progesterone (P(4)), androstenedione (A(2)) and nitrite release in the ovarian compartment on oestrus day and c) to demonstrate whether E(2) in the ganglion modifies the activity and gene expression in the ovary of the steroidogenic enzymes 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and 20α-hydroxysteroid dehydrogenase (20α-HSD). The ex vivo SMG-ovarian nervous plexus-ovary system was used. E(2), tamoxifen (Txf) and E(2) plus Txf were added in the ganglion to measure ovarian P(4) release, while E(2) alone was added to measure ovarian A(2) and nitrites release. Immunohistochemistry revealed cytoplasmic ERα immunoreactivity only in the neural somas in the SMG. E(2) increased ovarian P(4) and A(2) release at 15, 30 and 60 min but decreased nitrites. The activity and gene expression of 3ß-HSD increased, while the activity and gene expression of 20α-HSD did not show changes with respect to the control. Txf in the ganglion diminished P(4) release only at 60 min. E(2) plus Txf in the ganglion reverted the effect of E(2) alone and the inhibitory effect of Txf. The results of this study demonstrate that ERα activation in the SMG has an impact on ovarian steroidogenesis in rats, thus providing evidence for the critical role of peripheral system neurons in the control of ovarian functions under normal and pathological conditions.


Assuntos
Gânglios Simpáticos/metabolismo , Ovário/metabolismo , Receptores de Estrogênio/fisiologia , Esteroides/biossíntese , 20-Hidroxiesteroide Desidrogenases/genética , 20-Hidroxiesteroide Desidrogenases/metabolismo , 3-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Estradiol/farmacologia , Estro/efeitos dos fármacos , Estro/genética , Estro/metabolismo , Estro/fisiologia , Feminino , Gânglios Simpáticos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hormônios Esteroides Gonadais/biossíntese , Mesentério/inervação , Mesentério/metabolismo , Ovário/efeitos dos fármacos , Ovário/inervação , Progesterona/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/agonistas , Receptores de Estrogênio/metabolismo , Tamoxifeno/farmacologia
12.
Rev. bras. reprod. anim ; 35(2): 274-285, abr.-jun. 2011. ilus, tab
Artigo em Francês | VETINDEX | ID: biblio-1491971

RESUMO

L’insémination artificielle chez le chat domestique et les félidés sauvages répond à plusieurs indications. Chez le chat, elle peut notamment permettre d’aider la reproduction lorsque l’accouplement ne se produit pas ou difficilement et de favoriser les échanges géographiques de semence et donc un brassage et une meilleure sélection génétiques. Chez les félins sauvages, elle joue un rôle complémentaire au sein des programmes de conservation. Son utilisation est cependant complexe. L’oestrus et l’ovulation sont le plus souvent induits par l’emploi de gonadotropines qui possèdent cependant des effets indésirables, notamment un risque d’hyperstimulation ovarienne. La semence des mâles est généralement récoltée par électro-éjaculation. Elle peut être congelée. Néanmoins, un problème spécifique aux félins tient à la tératospermie, c'est-à-dire la production de nombreux spermatozoïdes porteurs d’anomalies morphologiques. L’insémination artificielle donne de meilleurs résultats lorsque la semence est déposée par voie intra-utérine. Pendant longtemps, la laparoscopie a été la technique de référence, mais récemment, des techniques de cathétérisme du col utérin par voie vaginale ont été mises au point, aussi bien chez le chat que chez certains félidés sauvages. Les résultats de l’insémination artificielle chez les félidés restent moyens.


Artificial insemination in the domestic cat and in wild felids has several indications. In the cat, it may replace natural reproduction when matings are unsuccessful or difficult, and it may help to perform geographical exchanges of semen and therefore enhance genetic improvement. In wild felids, it plays a complementary role inside conservation programs. However, its use is complex. First, oestrus and ovulation have to be induced. This is most often obtained using gonadotrophins, which unfortunately may induce undesirable effects, like ovarian hyperstimulation. In males, the semen is generally collected by electro-ejaculation. It may be frozen. However, teratospermia, which is the production of numerous spermatozoa showing morphological abnormalities, is a specific problem affecting felids. Intrauterine inseminations give better results. For a long period, laparoscopy was recommended in felids to perform intrauterine inseminations. Recently, new techniques consisting of catheterizing the cervix through a vaginal access have been developed in the cat as in some wild felids species. Altogether, the rate of success of artificial insemination in felids remains moderate.


A inseminação artificial em gatos domésticos e felídeos tem várias indicações. No gato, esta técnica substitui a reprodução natural quando as coberturas são mal sucedidas ou de difícil realização, além disso, auxilia geograficamente na permuta de sêmen contribuindo para aumentar a qualidade genética. Nos felídeos selvagens, esta técnica desempenha um papel complementar nos programas de conservação. Contudo, sua utilização é complexa. Inicialmente, há necessidade da indução do estro e ovulação. Geralmente isto é obtido por meio da utilização de gonadotrofinas que, infelizmente, induz a alguns efeitos indesejáveis, tais como, hiperestimulação ovariana. Nos machos, o sêmen geralmente é coletado por meio de eletroejaculação e este é submetido à congelaçãoAdicionalmente, a teratospermia, que é a produção de um grande número de espermatozóides com anormalidades morfológicas, é um problema específico que afeta os felídeos. Melhores resultados são obtidos com a inseminação intrauterina. Durante muito tempo recomendava-se a laparoscopia para a realização da inseminação intrauterina em felídeos. Recentemente, novas técnicas que consistem na cateterização da cérvix através do canal vaginal foram desenvolvidas no gato e em algumas espécies de felídeos selvagens. De modo geral, o índice de sucesso da inseminação artificial em felídeos ainda é considerado modesto.


Assuntos
Animais , Estro/genética , Indução da Ovulação , Indução da Ovulação/veterinária , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Preservação do Sêmen/veterinária , Técnicas Reprodutivas/tendências , Técnicas Reprodutivas/veterinária , Anestro , Espermatozoides/anormalidades , Espermatozoides/fisiologia , Fertilidade/genética , Hormônio Luteinizante
13.
R. bras. Reprod. Anim. ; 35(2): 274-285, abr.-jun. 2011. ilus, tab
Artigo em Francês | VETINDEX | ID: vti-8695

RESUMO

Linsémination artificielle chez le chat domestique et les félidés sauvages répond à plusieurs indications. Chez le chat, elle peut notamment permettre daider la reproduction lorsque laccouplement ne se produit pas ou difficilement et de favoriser les échanges géographiques de semence et donc un brassage et une meilleure sélection génétiques. Chez les félins sauvages, elle joue un rôle complémentaire au sein des programmes de conservation. Son utilisation est cependant complexe. Loestrus et lovulation sont le plus souvent induits par lemploi de gonadotropines qui possèdent cependant des effets indésirables, notamment un risque dhyperstimulation ovarienne. La semence des mâles est généralement récoltée par électro-éjaculation. Elle peut être congelée. Néanmoins, un problème spécifique aux félins tient à la tératospermie, c'est-à-dire la production de nombreux spermatozoïdes porteurs danomalies morphologiques. Linsémination artificielle donne de meilleurs résultats lorsque la semence est déposée par voie intra-utérine. Pendant longtemps, la laparoscopie a été la technique de référence, mais récemment, des techniques de cathétérisme du col utérin par voie vaginale ont été mises au point, aussi bien chez le chat que chez certains félidés sauvages. Les résultats de linsémination artificielle chez les félidés restent moyens.(AU)


Artificial insemination in the domestic cat and in wild felids has several indications. In the cat, it may replace natural reproduction when matings are unsuccessful or difficult, and it may help to perform geographical exchanges of semen and therefore enhance genetic improvement. In wild felids, it plays a complementary role inside conservation programs. However, its use is complex. First, oestrus and ovulation have to be induced. This is most often obtained using gonadotrophins, which unfortunately may induce undesirable effects, like ovarian hyperstimulation. In males, the semen is generally collected by electro-ejaculation. It may be frozen. However, teratospermia, which is the production of numerous spermatozoa showing morphological abnormalities, is a specific problem affecting felids. Intrauterine inseminations give better results. For a long period, laparoscopy was recommended in felids to perform intrauterine inseminations. Recently, new techniques consisting of catheterizing the cervix through a vaginal access have been developed in the cat as in some wild felids species. Altogether, the rate of success of artificial insemination in felids remains moderate.(AU)


A inseminação artificial em gatos domésticos e felídeos tem várias indicações. No gato, esta técnica substitui a reprodução natural quando as coberturas são mal sucedidas ou de difícil realização, além disso, auxilia geograficamente na permuta de sêmen contribuindo para aumentar a qualidade genética. Nos felídeos selvagens, esta técnica desempenha um papel complementar nos programas de conservação. Contudo, sua utilização é complexa. Inicialmente, há necessidade da indução do estro e ovulação. Geralmente isto é obtido por meio da utilização de gonadotrofinas que, infelizmente, induz a alguns efeitos indesejáveis, tais como, hiperestimulação ovariana. Nos machos, o sêmen geralmente é coletado por meio de eletroejaculação e este é submetido à congelaçãoAdicionalmente, a teratospermia, que é a produção de um grande número de espermatozóides com anormalidades morfológicas, é um problema específico que afeta os felídeos. Melhores resultados são obtidos com a inseminação intrauterina. Durante muito tempo recomendava-se a laparoscopia para a realização da inseminação intrauterina em felídeos. Recentemente, novas técnicas que consistem na cateterização da cérvix através do canal vaginal foram desenvolvidas no gato e em algumas espécies de felídeos selvagens. De modo geral, o índice de sucesso da inseminação artificial em felídeos ainda é considerado modesto.(AU)


Assuntos
Animais , Estro/genética , Indução da Ovulação , Indução da Ovulação/veterinária , Técnicas Reprodutivas/tendências , Técnicas Reprodutivas/veterinária , Preservação do Sêmen/veterinária , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Hormônio Luteinizante , Fertilidade/genética , Anestro , Espermatozoides/anormalidades , Espermatozoides/fisiologia
14.
Horm Behav ; 57(2): 216-21, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19958772

RESUMO

The aim of this investigation was to evaluate overall DNA damage induced by experimental paradoxical sleep deprivation (PSD) in estrous-cycling and ovariectomized female rats to examine possible hormonal involvement during DNA damage. Intact rats in different phases of the estrous cycle (proestrus, estrus, and diestrus) or ovariectomized female Wistar rats were subjected to PSD by the single platform technique for 96 h or were maintained for the equivalent period as controls in home-cages. After this period, peripheral blood and tissues (brain, liver, and heart) were collected to evaluate genetic damage using the single cell gel (comet) assay. The results showed that PSD caused extensive genotoxic effects in brain cells, as evident by increased DNA migration rates in rats exposed to PSD for 96 h when compared to negative control. This was observed for all phases of the estrous cycle indistinctly. In ovariectomized rats, PSD also led to DNA damage in brain cells. No significant statistically differences were detected in peripheral blood, the liver or heart for all groups analyzed. In conclusion, our data are consistent with the notion that genetic damage in the form of DNA breakage in brain cells induced by sleep deprivation overrides the effects related to endogenous female sex hormones.


Assuntos
Dano ao DNA , Hormônios Esteroides Gonadais/metabolismo , Privação do Sono/genética , Privação do Sono/metabolismo , Sono REM , Animais , Sangue/metabolismo , Encéfalo/metabolismo , Corticosterona/metabolismo , Diestro/genética , Diestro/fisiologia , Estro/genética , Estro/fisiologia , Feminino , Fígado/metabolismo , Miocárdio/metabolismo , Ovariectomia , Proestro/genética , Proestro/fisiologia , Progesterona/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Testosterona/metabolismo
15.
Braz. j. vet. res. anim. sci ; 43(6): 816-823, 2006. tab
Artigo em Português | LILACS | ID: lil-463905

RESUMO

Embora a técnica de inseminação artificial (IA) apresente inúmeras vantagens, no Brasil é empregada em apenas 7% das fêmeas de corte. Falhas na detecção de estros constituem o principal fator limitante para a obtenção de êxito no emprego da técnica. Um sistema eletrônico, que se baseia na radiotelemetria, foi desenvolvido para a detecção de estros. Este sistema fornece o registro da data, horário e duração das montas ocorridas. O presente estudo teve como objetivo avaliar, pelo sistema de radiotelemetria, as características comportamentais de estro em novilhas cruzadas de corte (Bos taurus taurus x Bos taurus indicus), criadas em regime extensivo, na região sudoeste do Brasil. A hipótese testada foi que a duração dos estros e o número de montas são bastante variáveis entre as fêmeas e que a maioria das montas ocorre no período noturno. Para a sincronização dos estros as novilhas receberam 0,5mg de MGA/cabeça/dia, uma vez ao dia, durante 8 dias, e uma injeção de 15mg de luprostiol (PG) via IM no último dia da ingestão de MGA. Os estros foram registrados pelo sistema de radiotelemetria "Heat-Watch", durante um período de até 120 horas após a aplicação de PG. A duração média dos estros foi de 10,4 ± 5,7 horas, duração que variou de 45 minutos a 22,7 horas. O número médio de montas foi de 26,2 ± 13,6 e variou de 3 a 81 montas. A duração média das montas foi de 2,7 ± 0,3 segundos. Dransfield et al. classificaram os estros em curta (< 7 horas) e longa (≥. 7 horas) duração e baixa (< 1,5 montas/hora) e alta (≥ 1,5 montas/hora) intensidade. Houve uma maior incidência dos estros de longa duração quando comparados aos de curta duração (72,8% vs. 27,2%; P<0,05) e uma maior incidência dos estros de alta intensidade quando comparados aos de baixa intensidade (70,2% vs. 29,8%; P<0,05). A média geral de montas diurnas foi de 10,0 ± 9,7 (das 7:00 às 19:00 horas) e de montas noturnas de 13,0 ± 12,4 (das 19:00 às 7:00 horas), sendo que não foi observado efeito de ...


Although artificial insemination (AI) has countless advantages, in Brazil this technique is performed in only 7% of beef cattle. Failures on estrous detection are the main limiting factor to the success of this technique. An electronical system, based on radiotelemetry, was developed for estrous detection. This system provides day, hour and service length. The present study aimed to evaluate by radiotelemetry system the behavioral characteristics of the estrous of crossbred heifers (Bos taurus taurus x Bos taurus indicus) raised at pasture regimen in southwest.


Assuntos
Bovinos , Estro/fisiologia , Estro/genética , Inseminação Artificial/métodos , Telemetria/métodos
16.
Braz. j. vet. res. anim. sci ; 43(6): 816-823, 2006. tab
Artigo em Português | VETINDEX | ID: vti-5561

RESUMO

Embora a técnica de inseminação artificial (IA) apresente inúmeras vantagens, no Brasil é empregada em apenas 7% das fêmeas de corte. Falhas na detecção de estros constituem o principal fator limitante para a obtenção de êxito no emprego da técnica. Um sistema eletrônico, que se baseia na radiotelemetria, foi desenvolvido para a detecção de estros. Este sistema fornece o registro da data, horário e duração das montas ocorridas. O presente estudo teve como objetivo avaliar, pelo sistema de radiotelemetria, as características comportamentais de estro em novilhas cruzadas de corte (Bos taurus taurus x Bos taurus indicus), criadas em regime extensivo, na região sudoeste do Brasil. A hipótese testada foi que a duração dos estros e o número de montas são bastante variáveis entre as fêmeas e que a maioria das montas ocorre no período noturno. Para a sincronização dos estros as novilhas receberam 0,5mg de MGA/cabeça/dia, uma vez ao dia, durante 8 dias, e uma injeção de 15mg de luprostiol (PG) via IM no último dia da ingestão de MGA. Os estros foram registrados pelo sistema de radiotelemetria "Heat-Watch", durante um período de até 120 horas após a aplicação de PG. A duração média dos estros foi de 10,4 ± 5,7 horas, duração que variou de 45 minutos a 22,7 horas. O número médio de montas foi de 26,2 ± 13,6 e variou de 3 a 81 montas. A duração média das montas foi de 2,7 ± 0,3 segundos. Dransfield et al. classificaram os estros em curta (< 7 horas) e longa (≥. 7 horas) duração e baixa (< 1,5 montas/hora) e alta (≥ 1,5 montas/hora) intensidade. Houve uma maior incidência dos estros de longa duração quando comparados aos de curta duração (72,8% vs. 27,2%; P<0,05) e uma maior incidência dos estros de alta intensidade quando comparados aos de baixa intensidade (70,2% vs. 29,8%; P<0,05).(AU)


Although artificial insemination (AI) has countless advantages, in Brazil this technique is performed in only 7% of beef cattle. Failures on estrous detection are the main limiting factor to the success of this technique. An electronical system, based on radiotelemetry, was developed for estrous detection. This system provides day, hour and service length. The present study aimed to evaluate by radiotelemetry system the behavioral characteristics of the estrous of crossbred heifers (Bos taurus taurus x Bos taurus indicus) raised at pasture regimen in southwest.(AU)


Assuntos
Estro/fisiologia , Estro/genética , Inseminação Artificial/métodos , Telemetria/métodos , Bovinos
17.
Transgenic Res ; 7(4): 311-7, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9859219

RESUMO

An understanding of the expression of transgenes in the mammary gland during gestation and lactation is crucial for the use of transgenic mammals as bioreactors. Here we describe the temporal pattern of expression of the endogenous rabbit WAP gene and human erythropoietin (hEPO) transgenes under the control of rabbit WAP promoter and 3' flanking sequences. The endogenous rabbit WAP gene was expressed throughout gestation including the day of mating, as well as during lactation in transgenic rabbits bearing a minigene construct. In non-pregnant cycling females, WAP expression was found independent of transgenic status; however, WAP expression was not detected in non-cycling females. The significance of this new finding is not clear at present. hEPO mRNA was detected in mammary gland biopsies from pregnant transgenic rabbits only on day 28 of gestation. During lactation, transcripts were present in mammary gland biopsy samples taken on days 0, 7, 14 and 21. A sharp decline in the levels of transcripts was found for an hEPOcDNA gene construct at the end of lactation (day 28). Although the levels of hEPO were too low to allow a conclusion to be drawn regarding temporal or position-dependent expression, this finding may reflect an integration position effect.


Assuntos
Eritropoetina/genética , Glândulas Mamárias Animais/metabolismo , Proteínas do Leite/genética , Animais , Animais Geneticamente Modificados , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , Estro/genética , Feminino , Expressão Gênica , Idade Gestacional , Humanos , Lactação/genética , Gravidez , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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