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1.
Anim Reprod Sci ; 216: 106467, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32414472

RESUMO

The aim of the present study was to determine the most suitable embryonic stage and embryo freezing technique for commercial implementation of frozen embryo trading by small-scale sheep producers. There was a 2 × 2 factorial design utilized for conducting the study consisting of two embryo stages (2-8 cells or morula/blastocyst) and two cryopreservation protocols (vitrification or slow-freezing). For the in vivo produced embryos, there were treatments of crossbred donor ewes to induce superovulation. Embryos were recovered surgically on either Day 2 or 5.5 after estrous onset. The embryos were cryopreserved using either a vitrification or slow-freezing method before there was transfer to recipients. Ovarian response, embryo survival and lambing outcomes were analyzed. There were no differences in number of recovered and fertilized embryos at the two embryonic developmental stages. There were no effects of embryonic stages and cryopreservation methods on pregnancy rate, twinning rate, fetal birth weights and lamb weight at 1 month of age. When there was use of vitrified embryos for transfers, there was a greater lamb weight at 2 months of age (8.38 ± 0.20 compared with 7.78 ± 0.21 kg; P = 0.044) than when there was transfer of embryos cryopreserved using slow freezing procedures. Considering economic and practical benefits to small-scale sheep farms, morula/blastocyst stage-embryo collection and transfer into the uterus is more efficacious than transferring 2-8 cells embryos into the oviduct. Results of this study may contribute to the genetic improvement in the flocks of small-scale sheep producers.


Assuntos
Transferência Embrionária/veterinária , Parto , Ovinos/embriologia , Vitrificação , Animais , Criopreservação/veterinária , Embrião de Mamíferos , Desenvolvimento Embrionário , Congelamento , Ovinos/fisiologia , Preservação de Tecido/métodos , Preservação de Tecido/veterinária , Coleta de Tecidos e Órgãos
2.
Res Vet Sci ; 111: 9-13, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28266317

RESUMO

The genetics of patellar luxation (PL) were investigated in Pomeranian dogs presented at the Small Animal Hospital, Faculty of Veterinary Science, Chulalongkorn University. A cohort of 339 Pomeranian dogs, part of a four-generation pedigree of 842 Pomeranians, was screened for PL from 2006 to 2013. PL was present in 77% of the screened dogs, with 84% having bilateral and 16% unilateral luxation. Medial PL was more common (95%) than lateral PL (2%) or bidirectional PL (3%). The risk of PL was similar in male and female dogs (female:male relative risk 1.11, 95% CI 0.98-1.25). The heritability of PL in the screened population was 0.44±0.04 using a threshold model. A genome-wide association study of PL (48 cases and 48 controls) using a high-density SNP array indicated the possible involvement of 15 chromosomal regions, of which CFA05 and CFA32 remained associated in a larger study involving an additional 128 cases and 7 controls. Candidate genes in these regions may be involved in the pathogenesis of PL in Pomeranian dogs.


Assuntos
Doenças do Cão/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Luxação Patelar/veterinária , Animais , Doenças do Cão/epidemiologia , Cães , Feminino , Masculino , Luxação Patelar/epidemiologia , Luxação Patelar/genética , Linhagem , Tailândia/epidemiologia
3.
Cryo Letters ; 35(4): 336-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25282502

RESUMO

BACKGROUND: The addition of a metal chelator, ethylenediaminetetraacetic acid (EDTA), to semen extender has the purpose of capturing trace element ions. OBJECTIVE: This study was conducted to evaluate the effects of EDTA on the quality and in vitro fertilisability of liquid-preserved boar spermatozoa. METHODS: In Experiment 1, semen samples were preserved in the semen extender supplemented with 0, 3, 6, or 12 mM of Na-EDTA at 5 degree C for 4 weeks. In Experiment 2, semen samples were preserved in the extender supplemented with 3 mM of Na-EDTA, Ca-EDTA, or Zn-EDTA and without chelator EDTA. RESULTS: When Na-EDTA was used as a chelating substance in the extender, 3 mM was a most suitable concentration for sperm motility and viability after cold preservation. The supplementation of 3 mM Ca-EDTA had advantages regarding sperm motility, viability and plasma membrane integrity. CONCLUSION: Our findings indicate that 3 mM Ca-EDTA is the most suitable metal-chelating substance for the liquid preservation of boar semen.


Assuntos
Quelantes/farmacologia , Ácido Edético/farmacologia , Substâncias Protetoras/farmacologia , Refrigeração , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/química , Fertilização in vitro , Masculino , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/citologia , Espermatozoides/fisiologia , Suínos , Fatores de Tempo
4.
Animal ; 8(7): 1139-45, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24804579

RESUMO

The world's first cloned swamp buffalo (Bubalus bubalis) derived from adult ear skin fibroblast has been reported. Donor fibroblast cells were produced from biopsies taken from adult male ear skin and in vitro matured oocytes obtained from a slaughterhouse were used as cytoplasts. A total of 39 blastocysts and 19 morulae fresh embryos were transferred into 12 recipient buffaloes. Progesterone assays indicated establishment of pregnancy in 10 of the 12 buffaloes (83.3%) after 45 days, with six animals still pregnant at 3 months. One recipient maintained pregnancy to term and naturally delivered a 40 kg male calf after 326 days of gestation. DNA analysis showed that the cloned calf was genetically identical to the donor cells. Genotype analyses, using 12 buffalo microsatellite markers, confirmed that the cloned calf was derived from the donor cell lines. In conclusion, the present study reports, for the first time, the establishment of pregnancy and birth of the first cloned Thai swamp buffalo derived from adult ear skin fibroblast cells.


Assuntos
Búfalos/embriologia , Clonagem de Organismos , Fibroblastos/citologia , Animais , Blastocisto , Búfalos/genética , Búfalos/crescimento & desenvolvimento , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/fisiologia , Feminino , Técnicas de Maturação in Vitro de Oócitos , Masculino , Técnicas de Transferência Nuclear , Gravidez
5.
Vet Comp Orthop Traumatol ; 26(6): 435-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23800782

RESUMO

In a prospective study, the outcome of surgical correction of medial patellar luxation of 70 stifle joints in 55 Pomeranian dogs was evaluated. Trochlear block recession alone was performed in 46 stifle joints, or in combination with tibial tuberosity transposition in 24 stifle joints in cases with grade II, III or IV medial patellar luxation. Additional procedures were performed to restore lateral and medial retinacular function. The recurrence of patellar luxation and the degree of lameness were evaluated up to at least 16 weeks after surgery. The overall recurrence rate was 10%. The outcome of surgery was considered good for grade II luxation with a 100% success rate. Recurrent medial patellar luxation was diagnosed in approximately 11% of dogs with grade III and in 36% of dogs with grade IV luxation. The postoperative lameness score decreased significantly in comparison with the preoperative score at four weeks and thereafter until the end of the study.


Assuntos
Doenças do Cão/cirurgia , Luxação Patelar/veterinária , Animais , Tamanho Corporal , Cães , Feminino , Masculino , Luxação Patelar/cirurgia , Complicações Pós-Operatórias/veterinária , Resultado do Tratamento
6.
Reprod Domest Anim ; 48(2): 305-10, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22834557

RESUMO

This study was examined whether the species of felid affects synchronization accuracy at the G0/G1 stage of the cell cycle and the occurrence of apoptosis by different protocols, such as serum starvation, confluent and roscovitine treatment. Skin fibroblast cells were obtained from the Asian golden cat, marbled cat, leopard and Siamese cat. The cells from each animal were treated with either serum starvation for 1-5 days, cell confluency-contact inhibition for 5 days or roscovitine at various concentrations (7.5-30 µm). Flow cytometric analysis revealed that serum starvation for 3 days provided the highest cell population arrested at the G0/G1 stage, irrespective of the felid species. In all species, 100% confluency gave a significantly higher percentage of cells arrested at the G0/G1 stage compared with the non-treated control cells. The effects of roscovitine treatment and the appropriate concentration on the rates of G0/G1 cells differed among the felid species. Serum starvation for more than 4 days in the marbled cat and Siamese cat and roscovitine treatment with 30 µm in the Asian golden cat and leopard increased the rates of apoptosis. In conclusion, different felid species responded to different methods of cell cycle synchronization. Asian golden cat and Siamese cat fibroblast cells were successfully synchronized to G0/G1 stage using the serum starvation and roscovitine treatment, whereas only confluency-contact inhibition treatment induced cell synchronization in the leopard. Moreover, these three methods did not successfully induce cell synchronization of the marbled cat. These findings may be valuable for preparing their donor cells for somatic cell nuclear transfer in the future.


Assuntos
Ciclo Celular/fisiologia , Felidae/classificação , Felidae/fisiologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Animais , Meios de Cultura Livres de Soro/farmacologia , Fibroblastos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Roscovitina , Especificidade da Espécie
7.
Theriogenology ; 79(1): 149-58, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23138024

RESUMO

Cryopreservation of testicular tissue associated with intracytoplasmic sperm injection (ICSI) is a critical tool that still needs to be explored for preserving the fertility of endangered species. Using the domestic cat as a model for wild felids, the study aimed at determining the effect of different cryoprotectants and freezing techniques (two-step freezing vs. controlled slow freezing) on the sperm quality (membrane and DNA integrity). Then, spermatozoa were extracted from frozen-thawed testicular tissues and used for ICSI to assess early gamete activation or developmental competence in vitro. The percentage of spermatozoa with intact plasma membrane was not different (P > 0.05) among nonfrozen control, glycerol-, and ethylene glycol-frozen tissues (63.2 ± 2%, 58.2 ± 2.6%, 53.3 ± 2.3%, respectively). However, these percentages were significantly lower (P < 0.05) in groups of dimethyl sulfoxide (46.3 ± 3.3%) and 1,2 propanediol (44.3 ± 2.9%) when compared with control. Conventional freezing combined with 5% (vol/vol) glycerol best preserved sperm membrane integrity (55.0 ± 2.7%) when compared with other freezing techniques. The incidence of DNA fragmentation was found to be low (0.2%-1.1%) in all freezing protocols. After ICSI with frozen testicular spermatozoa, male and female gametes were asynchronously activated and the percentages of normal fertilization at 6, 12, and 18 hours were 11.2%, 20.6%, and 22.1%, respectively. Metaphase II-arrested oocytes containing or not a decondensed sperm head were predominantly found after ICSI with frozen testicular spermatozoa. Although two-pronucleus formation could be observed as soon as 6 hours post ICSI (10%), the rate increased dramatically after 12 and 18 hours post ICSI (17.2% and 19.5%, respectively). ICSI using frozen-thawed testicular spermatozoa yielded cleavage (32.7%), morula (6.5%), and blastocyst (4.4%) percentages similar to nonfrozen control (P > 0.05). It is concluded that conventional freezing technique with glycerol as a principle cryoprotectant is simplified and applicable for cat testicular tissue cryopreservation. We also demonstrate for the first time that feline spermatozoa derived from frozen-thawed testicular tissues retain their fertilizing ability and can be used to produce ICSI-derived embryos.


Assuntos
Desenvolvimento Embrionário/fisiologia , Injeções de Esperma Intracitoplásmicas , Recuperação Espermática , Espermatozoides/citologia , Testículo/citologia , Animais , Gatos , Separação Celular , Células Cultivadas , Criopreservação/métodos , Criopreservação/veterinária , Feminino , Fertilidade/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Injeções de Esperma Intracitoplásmicas/veterinária , Recuperação Espermática/veterinária
8.
Theriogenology ; 77(7): 1415-24, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22225682

RESUMO

The objectives were to: (1) examine the efficiency of intracytoplasmic sperm injection (ICSI) technique, with or without chemical activation of in vitro matured buffalo oocytes, on sperm head decondensation; and (2) compare the subsequent development of embryos after activation of ICSI (ICSI (+) activation group) and sham injection (Sham (+) activation group) oocytes (embryos obtained by in vitro fertilization of IVM oocytes served as a control group). Pronuclear formation rates in ICSI (+) activation and Sham (+) activation groups were higher than that of ICSI without activation (P < 0.05). However, because 90.9% of presumptive zygotes in ICSI (+) activation group demonstrated pronuclear formation with an intact sperm head, we inferred that most were parthenotes. Neither developmental competence (morula and blastocyst formation rates) nor mean total cell number of blastocysts was significantly different among ICSI (+) activation, Sham (+) activation, and IVF groups. To clarify whether blastocysts were derived from syngamy or parthenogenesis, expression of Nnat, a paternally expressed gene in blastocysts derived from IVF, ICSI and oocyte activation without sperm or sham injection was additionally examined using reverse transcription polymerase chain reaction (RT-PCR). Expression of Nnat mRNA was not detected in ICSI (+) activation blastocysts, indicating failure of male genome activation. Although blastocyst development after ICSI combined with chemical activation was similar to IVF oocytes, these blastocysts were generated by parthenogenesis, due to failure of male pronucleus formation.


Assuntos
Búfalos/genética , Injeções de Esperma Intracitoplásmicas/veterinária , Interações Espermatozoide-Óvulo , Animais , Búfalos/fisiologia , Desenvolvimento Embrionário , Feminino , Expressão Gênica , Masculino , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/metabolismo , Injeções de Esperma Intracitoplásmicas/métodos
9.
Theriogenology ; 77(1): 1-11, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21958632

RESUMO

In female swine, PGF2α is an important regulator of corpora luteal (CL) function, uterine contractility, ovulation, and embryo attachment. High affinity PGF2α receptors are present in the CL at all stages of the estrous cycle and they are functional. Therefore, a lack of luteolytic capacity of PGF2α is related to other factors that have not been well identified. In female pigs, a single exogenous PGF2α injection produces a short lasting decrease in plasma progesterone levels but does not induce luteolysis before day 12 of the estrous cycle. However, multiple injections of PGF2α can induce luteolysis before day 12 of the estrous cycle and may be utilized in the development of protocols for ovulation synchronization and timed AI. Most commonly, PGF2α is used for the induction of farrowing and so facilitation of cross fostering. Further, since PGF2α is a smooth muscle stimulant, treatment to stimulate myometrial contractions and uterine evacuation of residual products from parturition or infectious debris, may have beneficial effects on post-weaning fertility. Administration of PGF2α at the moment of insemination has been shown to improve reproductive performances when fertility is otherwise low, such as in sow under summer heat stress.


Assuntos
Corpo Lúteo/efeitos dos fármacos , Dinoprosta/farmacologia , Reprodução/efeitos dos fármacos , Suínos/fisiologia , Animais , Dinoprosta/administração & dosagem , Ciclo Estral/efeitos dos fármacos , Feminino , Inseminação Artificial/veterinária , Luteólise/efeitos dos fármacos , Período Pós-Parto , Gravidez , Receptores de Prostaglandina/metabolismo
10.
Reprod Domest Anim ; 47 Suppl 6: 305-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23279525

RESUMO

The aim of this study is to produce live kittens from oocytes fertilized by intracytoplasmic sperm injection (ICSI) with frozen/thawed testicular spermatozoa. Spermatozoa were collected from thawed testicular tissue and subsequently injected into in vitro matured cat oocytes. At 24 h post-ICSI, presumptive zygotes/cleaved embryos were treated with 10 µm forskolin for 24 h to reduce intracellular lipid content of embryos (delipidation). At 48 h after oocyte injection, cleaved embryos (2- to 8-cell stage) were frozen in 10% (v/v) ethylene glycol-based medium by a slow controlled rate method and stored in liquid nitrogen. To evaluate in vitro and in vivo developmental competence, frozen embryos were thawed and then cultured for 6 days (n = 155) or cultured for 2 h before transferred (n = 209) to hormonal (equine chorionic gonadotropin/hCG)-treated cat recipients. Cleavage frequency at day 2 after ICSI with frozen/thawed testicular spermatozoa was ~30%. The percentages of frozen/thawed embryos that developed to morula and blastocyst stage (on day 3 and day 6 of in vitro culture, respectively) were significantly lower than that of fresh ICSI embryos (22.6 vs 45.2% and 21.3 vs 38.7%, respectively; p < 0.05). However, no difference was found in the number of blastomeres between frozen/thawed (242.5 ± 43.1) and fresh (320.2 ± 28.1) blastocysts. Three of seven cat recipients were pregnant and one pregnant cat delivered two healthy kittens. This is the first report of the birth of kittens after the transfer of frozen-thawed embryos produced by ICSI with frozen/thawed testicular sperm.


Assuntos
Gatos/embriologia , Injeções de Esperma Intracitoplásmicas/veterinária , Espermatozoides/fisiologia , Testículo/fisiologia , Animais , Criopreservação/veterinária , Transferência Embrionária/veterinária , Feminino , Masculino , Gravidez
11.
Reprod Domest Anim ; 46(5): 824-31, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21749483

RESUMO

This study was designed with the final goal of improving in vitro embryo production in the Thai swamp buffalo (Bubalus bubalis carabensis). Oocytes were collected by ovum pick-up (OPU) from six non-lactating multiparous swamp buffalo twice per week for 10 consecutive sessions followed by once-weekly collection for 10 consecutive sessions without hormone stimulation. In addition, oocytes were collected from slaughterhouse ovaries that were classified as follows: ovaries from non-pregnant cows with a visible corpus luteum (NPCL); pregnant cows with a corpus luteum (P); and non-pregnant cows without a corpus luteum (NP). Follicles in each group of ovaries were categorized as small (2-4 mm), medium-sized (5-8 mm) or large follicles (≥ 9 mm). The quality of the oocytes was assessed by their capacity to undergo in vitro maturation. The total number of observed follicles per session (all sizes combined) was larger in the once-weekly OPU group compared with the twice-weekly OPU group. In particular, the numbers of small and large follicles were higher in the once-weekly OPU group (5.2 ± 0.7 and 0.9 ± 0.2, respectively) than in the twice-weekly OPU group (3.9 ± 0.5 and 0.5 ± 0.1). The number of medium-sized follicles did not differ between the groups. The percentages of oocytes with an abnormal spindle morphology were not different between oocytes from the twice-weekly (30.0%) and the once-weekly (28.6%) OPU groups. A higher percentage of oocytes obtained in vitro (49.5%) exhibited nuclear abnormalities compared with those obtained in vivo (≤34.8%) after in vitro maturation. In conclusion, oocytes can be successfully collected by OPU in the swamp buffalo, without hormonal pretreatment, and per week more good-quality oocytes can be collected by twice-weekly OPU. In addition, oocytes collected from slaughterhouse ovaries can be used with the reproductive status of the cow having no influence on the maturation competence of oocytes.


Assuntos
Matadouros , Búfalos/fisiologia , Oócitos/fisiologia , Ovário/fisiologia , Coleta de Tecidos e Órgãos/veterinária , Ultrassonografia/veterinária , Animais , Feminino , Ovulação , Coleta de Tecidos e Órgãos/métodos
12.
Theriogenology ; 75(9): 1742-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21458054

RESUMO

Cryopreservation of stallion semen is often associated with poor post-thaw sperm quality. Sugars are among the important components of a freezing extender and act as non-permeating cryoprotectants. This study aimed to compare the quality of stallion sperm frozen with glucose, fructose or sorbitol-containing freezing extenders. Semen was collected from six stallions of proven fertility and cryopreserved using a freezing extender containing different types of monosaccharide sugars (glucose, fructose or sorbitol). After thawing, the semen was examined for sperm motility, viability, acrosome integrity, plasma membrane functionality and sperm longevity. The fertility of semen frozen in the presence of sorbitol was also tested by artificial insemination. Sperm quality was significantly decreased following freezing and thawing (P < 0.05). Fructose was inferior for protecting sperm during cryopreservation when compared to sorbitol and glucose (P < 0.05). Although the viability, motility and acrosome integrity of sperm cryopreserved with a glucose-containing extender did not significantly differ from sperm frozen in the sorbitol-based extender when examined at 2 and 4 h post-thaw, all of these parameters plus plasma membrane functionality were improved for sperm frozen in the sorbitol extender than in the glucose extender when examined 10 min post-thaw. Two of four mares (50%) inseminated with semen frozen with a sorbitol-containing freezing extender became pregnant. It is concluded that different sugars have different abilities to protect against cryoinjury during freezing and thawing of stallion sperm. This study demonstrated that an extender containing sorbitol as primary sugar can be used to successfully cryopreserve equine sperm; moreover, the quality of frozen-thawed sperm appeared to be better than when glucose or fructose was the principle sugar in the freezing extender.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cavalos , Sêmen , Sorbitol/farmacologia , Espermatozoides/fisiologia , Acrossomo/fisiologia , Acrossomo/ultraestrutura , Animais , Membrana Celular/ultraestrutura , Criopreservação/métodos , Crioprotetores/química , Inseminação Artificial/veterinária , Masculino , Análise do Sêmen/veterinária , Sorbitol/química , Motilidade dos Espermatozoides , Espermatozoides/ultraestrutura
13.
Theriogenology ; 75(9): 1708-19, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21396699

RESUMO

Morphology and gene expression are the currently preferred methods for assessing the effect of culture medium and density on embryos of several species. To define their effects on domestic cat embryos, groups of 8-10 embryos were cultured in SOF, modified Tyrode's solution or MK-1 medium in a fixed volume (50 µL) and in different volumes (20, 50 and 100 µL). SOF supplemented with different concentrations of glucose (1.5, 3.0 and 6.0 mM) was used to examine the effect of glucose level on embryo development. Real-time reverse transcriptase polymerase chain reaction was used to determine the relative transcripts of BAX, BCL-2 and GLUT-1 genes in blastocysts derived from various concentrations of glucose. SOF and MK-1 supported feline embryo development better than modified Tyrode's solution. Embryos cultured in 20 µL droplets showed decreased development in all three media (P < 0.05). Increasing the glucose concentration in SOF to 6.0 mM adversely affected embryo development and tended to increase the BCL-2 transcript in blastocysts. In conclusion, type of culture medium, embryo density and glucose concentration affected the development of domestic cat embryos. High culture density and glucose concentration negatively affected embryo development. The increase of anti-apoptotic BCL-2 expression found in blastocysts cultured in 6.0 mM glucose may have prevented an increase in the incidence of apoptosis. In the present study, it was clearly demonstrated that differential gene expression occurred in embryos with similar morphology.


Assuntos
Gatos/embriologia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/genética , Expressão Gênica/efeitos dos fármacos , Animais , Gatos/genética , Meios de Cultura , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Glucose/farmacologia , Transportador de Glucose Tipo 1/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína X Associada a bcl-2/genética
14.
Theriogenology ; 75(6): 1029-38, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21196044

RESUMO

ß-carotene is the main natural precursor of vitamin A and plays an important role in reproductive efficiency and immune function in dairy cows. The objective of this study was to investigate whether a supplement of ß-carotene given during the dry period is able to 1) increase blood concentrations of ß-carotene postpartum, 2) improve ovarian function and progesterone production, and 3) enhance uterine involution and uterine health. This study was conducted using 40 Holstein cows. On the day of drying-off, cows were allocated to one of two dietary treatments: control diet (C, n = 20) or control diet plus 1g/d ß-carotene (BC, n = 20). The ß-carotene supplement was given individually to the cows until calving. Blood samples were obtained regularly before and after calving from the cows to measure the concentrations of ß-carotene. The diameters of the cervix and uterine horns were measured regularly using ultrasonography. Endometrial cytology samples were acquired from the cervix and uterus to determine uterine health. Milk samples were obtained three times per week for progesterone assay. Additional blood samples were taken on the day of calving, 7 and 21 days postpartum to determine the plasma concentrations of amino acids. Blood concentrations of ß-carotene were not different before the start of the experiment (C, 3.03 ± 0.22 mg/L vs BC, 3.12 ± 0.22 mg/L, P > 0.05). Blood concentrations of ß-carotene in the BC group peaked (7.45 ± 0.24 mg/L) 1 month after drying-off while the concentrations in the C group remained constant. ß-carotene concentrations then decreased in both groups. The difference in blood concentrations of ß-carotene between groups became significant 2 weeks after the start of the supplement until 2 weeks postpartum. There was no significant difference in the interval from calving to ovulation between groups (C, 27.8 ± 3.46 d vs BC, 35.8 ± 3.55 d, P > 0.05). The dietary supplement of ß-carotene during the dry period had no effect on ovarian activity, progesterone production, cervix and uterine horn diameters. Plasma concentrations of hydroxyproline in the BC group were higher than in the C group on day 21 postpartum (BC, 20.8 ± 1.33 µmol/L vs C, 15.0 ± 1.33 µmol/L; P < 0.01). On day 28 postpartum the percentage of neutrophils in the BC group was lower than in the C group (cervical smear; C, 21.0 ± 3.22% vs BC, 9.7 ± 3.14%, P < 0.05 and uterine smear; C, 32.0 ± 3.86% vs BC, 20.9 ± 3.76%, P < 0.05). In the present experiment a dietary supplement of ß-carotene had no effect on ovarian activity. However, due to effects of ß-carotene on hydroxyproline profiles and their potential relationship with uterine function we speculate that uterine involution may have been more complete and that uterine inflammation may have been reduced in cows which received the ß-carotene compared to controls.


Assuntos
Colo do Útero/efeitos dos fármacos , Ovário/efeitos dos fármacos , Período Pós-Parto , Progesterona/metabolismo , Útero/efeitos dos fármacos , beta Caroteno/farmacologia , Aminoácidos/sangue , Animais , Bovinos , Colo do Útero/anatomia & histologia , Colo do Útero/citologia , Suplementos Nutricionais , Feminino , Leite/química , Ovário/fisiologia , Útero/anatomia & histologia , Útero/citologia , beta Caroteno/sangue
15.
Reprod Domest Anim ; 46(1): e91-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20546176

RESUMO

This study characterized follicular activity and oestrous behaviour from 5 to 9 days post-calving up to the 4th ovulation postpartum (pp) in 16 multiparous (range 2-7 parities) Thai swamp buffalo cows (Bubalus bubalis), aged 4-12 years and weighing from 432 to 676 kg. Ovarian follicular activity was examined by transrectal ultrasonography (TUS) every morning. Oestrous detection was performed twice daily by direct personal observation of behaviour and for presence of clear cervical mucus discharge and indirectly by video camera recording during 21 h/day. A follicular wave-like pattern was present before the 1st ovulation leading to short oestrous cycles. Growth rates and maximum diameters of the ovulatory follicles did not differ between the 1st and 4th ovulations. However, growth rate for non-ovulatory dominant follicles (DF) before the 1st ovulation was lower than for the ovulatory follicle (p<0.05). In addition, the diameter of all ovulatory follicles (14.3 ± 0.46 mm, n=39) was significantly larger (p < 0.01) than those of the preceding last but one non-ovulatory DF (10.8 ± 0.20 mm, n = 5), but similar to the last preceding non-ovulatory DF diameter (12.92 ± 0.96 mm, n = 14). Short oestrous cycles were most common between the 1st and 2nd ovulations (93.75%, 15/16 cows, 10.2 ± 0.38 days) decreasing in prevalence thereafter (50%, 3/6 buffaloes, 12.0 ± 1.53 days). Oestrous signs were relatively vague around the 1st ovulation pp to become more easily detectable thereafter. This study suggests that properly fed swamp buffaloes could be mated successfully within 2 months pp, at their 2nd spontaneous ovulation, provided oestrous detection is at least performed daily at 06:00-08:00 hour.


Assuntos
Búfalos/fisiologia , Detecção do Estro , Folículo Ovariano/fisiologia , Período Pós-Parto , Animais , Comportamento Animal , Cruzamento , Muco do Colo Uterino/metabolismo , Ciclo Estral/fisiologia , Detecção do Estro/métodos , Feminino , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/diagnóstico por imagem , Ovulação , Progesterona/sangue , Tailândia , Ultrassonografia
16.
Theriogenology ; 75(5): 897-903, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21167582

RESUMO

Sperm plasma membrane lipids have an important role to play in determining membrane fluidity and sperm motility. The objective of the present study was to determine whether there are differences in the lipid and fatty acid (FA) composition of boar sperm and seminal plasma in the ejaculates of boars having different sperm motilities. Semen was collected from two groups of boars having normal (> 60%; n = 53) or low (< 60%; n = 53) motility sperm and the semen was evaluated for motility, morphology and vitality. The semen was then centrifuged to separate the sperm from the seminal plasma and both were kept at -20 °C until analyzed for lipid content and FA profile by gas chromatography. Total antioxidant status (TAS) of seminal plasma was determined using a commercial kit. There were differences (P ≤ 0.05) in sperm total lipids, cholesterol, saturated fatty acids (SFA), phospholipids, n-3 polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA) and the ratio of n-6:n-3 PUFA between boars with normal and low motility sperm. Total lipids, cholesterol, phospholipids, PUFA, DHA and n-3 PUFA were positively correlated with sperm motility, viability, normal morphology and normal plasma membrane. In contrast, SFA and the ratio of n-6: n-3 PUFA were negatively correlated (P ≤ 0.05) with sperm motility, viability, normal morphology and normal plasma membranes. The TAS of seminal plasma from boars having normal motility sperm was higher (P ≤ 0.05) than that of boars having low motility sperm and TAS was positively correlated (P = 0.0001) with sperm motility, viability, normal morphology and normal plasma membranes. In summary, differences in sperm motility were related to n-3 PUFA content in the sperm plasma membrane and extracellular antioxidants in seminal plasma which protect sperm plasma membranes from lipid peroxidation during periods of oxidative stress.


Assuntos
Lipídeos/análise , Sêmen/química , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/química , Suínos/fisiologia , Animais , Antioxidantes/análise , Membrana Celular/química , Colesterol/análise , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Masculino , Fosfolipídeos/análise , Espermatozoides/anormalidades , Espermatozoides/ultraestrutura
17.
Theriogenology ; 74(8): 1371-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20708229

RESUMO

This study evaluated fertility in swamp buffalo after synchronization of ovulation combined with fixed time artificial insemination. At the start of the study, designated day 0, from a group of 98 female Thai swamp buffalo, 55 buffalo (heifers n° = 20 and cows n° = 35) were selected to be synchronized with GnRH (Day 0) followed by PGF2alpha (Day 7) and a second treatment with GnRH (Day 9). All buffalo were inseminated at two fixed times 12 h and 24 h after the second injection of GnRH (Ovsynch+TAI group); a second group of 43 buffalo (heifers n° = 19 and cows n° = 24) were not treated and were artificially inseminated (AI) at natural estrus (AI group). Blood samples were taken 22 days after insemination to evaluate progesterone plasma levels. In the Ovsynch+TAI group, overall conception rate (CR; i.e. the number of cows with progesterone >4.0 ng/ml on day 22 after AI divided by the number of animals inseminated), was 38.1% and overall pregnancy rate (PR; i.e. the number of cows that were pregnant at day 50-60 after insemination divided by the number of animals inseminated), was 32.7%. In the AI group overall CR and PR was 34.9%. Within the Ovsynch+TAI group, CR and PR were reduced (P < 0.05) in heifers compared with cows (CR 15.0% vs. 51.4% for heifers and cows, respectively; PR 15.0% vs. 42.9% for heifers and cows, respectively). Within the AI group the efficacy of treatment was similar between heifers and cows (CR and PR 31.6% for heifers and 37.5% for cows). In conclusion, this study indicates that in swamp buffalo it is possible to synchronize ovulation and use timed artificial insemination with the Ovsynch+TAI protocol.


Assuntos
Búfalos/fisiologia , Dinoprosta/farmacologia , Fármacos para a Fertilidade/farmacologia , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/veterinária , Indução da Ovulação/veterinária , Animais , Feminino , Masculino , Progesterona/sangue
18.
Anim Genet ; 41(4): 433-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20219068

RESUMO

Y-chromosomal variation in the water buffalo was analysed by sequencing of DBY, ZFY and SRY gene segments. A clear separation of the paternal lineages of the river and swamp types parallels the differences between their maternal lineages and nuclear DNA. Sequence divergence was found to be comparable to the divergence of taurine cattle and zebu, and this divergence predated domestication, confirming that river and swamp buffalo originated from different wild populations. Within a sample of 23 Thai swamp buffaloes, we identified four haplotypes with different geographical distributions, two of which were shared by Thai wild buffaloes.


Assuntos
Búfalos/genética , Cromossomo Y , Animais , Bovinos , Filogenia , Mutação Puntual , Rios , Tailândia , Áreas Alagadas
19.
Theriogenology ; 73(1): 120-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19880167

RESUMO

Intergeneric nucleus transfer (ig-NT) is a promising technique to produce offspring of endangered species. The objectives of this study were to (1) investigate the in vitro development of marbled cat (MC; Pardofelis marmorata) and flat-headed cat (FC; Prionailurus planiceps) ig-NT embryos reconstructed from domestic cat (DC; Felis catus) oocytes (Experiment 1), (2) evaluate the effect of individual FC donor cell lines on NT success (Experiment 2), and (3) assess the developmental ability of FC-cloned and DC-IVF embryos in vitro and in vivo after oviductal transfer (Experiment 3). In Experiment 1, the morula rate of FC-reconstructed embryos was significantly higher than those of MC and DC embryos but lower than that of parthenogenic DC embryos. However, blastocyst rate was not different. In Experiment 2, FC-ig-NT embryos reconstructed from female muscular tissue had significantly higher morula rate in comparison with those derived from other donor cell lines. However, there was no difference in blastocyst rate among cell lines. In Experiment 3, in vitro development of FC-ig-NT embryos was lower than that of DC-IVF embryos. The competency of in vivo development of FC-ig-NT and/or DC-IVF embryos was investigated by assessing pregnancy rate after their transfer into DC recipients. Domestic cat recipients receiving only FC-ig-NT embryos, FC-ig-NT embryos in one side of the oviduct and DC-IVF embryos contralaterally (co-transfer), and only DC-IVF embryos were observed. No pregnancy was detected in all recipients receiving FC-ig-NT embryos. One recipient receiving co-transferred embryos became pregnant, then delivered DC-IVF dead fetuses (n=2) and live kittens (n=6). All recipients receiving DC-IVF embryos became pregnant, and three of six recipients delivered five DC-IVF kittens. These results illustrate the developmental capacity of MC- and FC-ig-NT embryos up to the blastocyst stage. Individual donor cell line affects the developmental success up to the morula stage of FC-ig-NT embryos. Improving the developmental competence and quality of FC-ig-NT embryos may be required for implantation and development to term of FC-ig-NT offspring.


Assuntos
Felidae , Técnicas de Transferência Nuclear , Animais , Gatos , Linhagem Celular , Clonagem de Organismos/métodos , Transferência Embrionária , Desenvolvimento Embrionário , Espécies em Perigo de Extinção , Feminino , Fertilização in vitro , Oócitos/citologia , Gravidez , Resultado da Gravidez/veterinária
20.
Theriogenology ; 73(2): 199-207, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19900701

RESUMO

The developmental competence of cat oocytes matured in vitro is relatively poor when compared with that of in vivo oocytes. The study aimed to investigate the effect of roscovitine on the developmental competence of cat Felis catus oocytes matured in vitro. Cumulus-oocyte complexes (COCs) were classified as Grade I and II to III. Groups of COCs were cultured in 0, 12.5, 25, 50, 100, and 200 microM roscovitine for 24h and were either fixed to assess the stages of nuclear maturation (Experiment 1) or additionally matured in vitro for 24h before fixation (Experiment 2). In Experiment 3, cumulus cells from the COCs treated with roscovitine were examined for apoptosis. Experiment 4 examined the developmental competence of cat oocytes after roscovitine treatment and in vitro fertilization in terms of cleavage and morula and blastocyst formation rates. Roscovitine reversibly arrested cat oocytes at an immature stage in a dose-dependent manner. Roscovitine at 12.5 and 25 microM demonstrated less efficiency compared with that of other doses. However, higher doses of roscovitine induced cumulus cell apoptosis and resulted in a high number of degenerated oocytes after in vitro maturation. Roscovitine at 12.5 and 25 microM were therefore used to evaluate their effect on embryo development. Pretreatment with 12.5 and 25 microM roscovitine prior to in vitro maturation decreased the developmental competence of cat oocytes compared with that of non-roscovitine-treated controls. In conclusion, roscovitine reversibly maintained cat oocytes at the germinal vesicle stage without detrimental effect on nuclear maturation. However, it negatively affected cumulus cell viability and developmental competence.


Assuntos
Apoptose/efeitos dos fármacos , Células do Cúmulo/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Animais , Gatos , Técnicas de Cultura de Células , Feminino , Meiose/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Roscovitina
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