Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Vet Sci ; 11: 1376057, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812559

RESUMO

The purpose of this study was to improve the quality of frozen-thawed Piedmontese bull semen by incorporating MitoTEMPO (MT) in extended semen before cryopreservation. Semen was collected from 4 fertile bulls, using an artificial vagina, once weekly for 6 consecutive weeks. Semen samples were pooled, diluted with Bullxcell® extender, and supplemented with different concentrations of MT (0 as control, 5, 10, 20, 40, and 80 µM) before cooling, equilibration, and freezing procedures. The frozen-thawed semen was assessed for motility, vitality, acrosome intactness, plasma membrane integrity, DNA integrity, apoptosis, mitochondrial membrane potential, intracellular ROS level and in vitro fertilizing capability. The results showed that MT at concentrations of 10, 20, and 40 µM improved the total, progressive, and rapid motility directly after thawing while, at the highest tested concentration (80 µM), it decreased the progressive and rapid motility after 1, 2, and 3 h of incubation. The sperm kinetics including STR and LIN were noticeably increased at concentrations of 10, 20, and 40 µM directly after thawing (0 h), whereas the MT effect was variable on the other sperm kinetics during the different incubation periods. MitoTEMPO improved the sperm vitality at all tested concentrations, while the acrosomal and DNA integrity were improved at 20 µM and the mitochondrial membrane potentials was increased at 80 µM. The cleavage and blastocyst formation rates were significantly increased by using semen treated with 20 µM MT compared with controls. These findings suggest a potential use of MT mainly at a concentration of 20 µM as an additive in the cryopreservation media of bull semen to improve sperm quality.

2.
Animals (Basel) ; 13(11)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37889745

RESUMO

The selection of the recipient mare is one of the most important factors involved in the success of equine embryo transfer. The aim of this study was to determine whether the age of the recipient, the number of transfers and the detection of intrauterine fluid during the follicular phase or after ovulation can affect pregnancy rate at 14 and 45 days (PR 14 and PR 45) or early embryonic loss (EEL). A total of 1222 ETs were included in the study. Mares receiving the first embryo of the year had a higher PR 14 and 45 days compared to mares at the third transfer (78.8% and 70.1% vs. 65.6% and 54.1%, respectively). The detection of intrauterine fluid post ovulation negatively affected PR 14 (60.5% vs. 77.6%) and should therefore be considered an abnormal finding, probably being a sign of uterine inflammation or delayed uterine clearance. On the contrary, the age of the recipient mare and detection of fluid during follicular phase did not affect PR 14. Only the age of the recipient mare influenced the EEL, since mares aged 10-13 years had a higher EEL compared to mares aged 3-5 years (15.6% vs. 6.4%). Embryo size and grade affected PR 14 and 45.

3.
J Equine Vet Sci ; 121: 104222, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623580

RESUMO

Mares' subfertility represents a complex diagnostic and therapeutic challenge and both clinical and subclinical endometritis are considered major causes of impaired fertility. Thanks to its properties, ozone has a big potential as a treatment for equine endometritis. Therefore, the aim of this study is to describe the safety and the effects on endometrium and reproductive parameters of mares of a commercial ozone foam preparation (Riger Spray®). Twenty-four mares were treated during estrus: ozone group with an intrauterine instillation of ozone foam preparation (OG, n=16) and control group with 20 ml of lactated Ringer's solution (CG, n=8). Samples for endometrial cytology were collected before the ozone treatment (T0), after 24 h (T1), after one week (T2), two weeks (T3), and when the subsequent estrous phase was detected (T4). Furthermore, samples for histological examination and uterine swab for bacteriological examination were collected at T0 and T4. At T1, a statistically significant increase of endometrial inflammation in the OG mares compared to T0 (P<.05) and to CG at same time point (P<.05) was observed, but it was already resolved at T2. No differences in endometrial inflammation in CG, biopsy grade before and after the treatment in the two groups, number of mares pregnant at the end of the season and number of mares pregnant at the first cycle were observed. However, the number of inseminations required for pregnancy tended to be lower (P=.0711) in the OG (1.69±0.06) than in CG mares (2.60±0.89).


Assuntos
Endometrite , Doenças dos Cavalos , Gravidez , Cavalos , Animais , Feminino , Endometrite/tratamento farmacológico , Endometrite/veterinária , Doenças dos Cavalos/induzido quimicamente , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/diagnóstico , Endométrio , Fertilidade , Inflamação/complicações , Inflamação/patologia , Inflamação/veterinária
4.
Theriogenology ; 198: 217-223, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610371

RESUMO

Dairy cows diagnosed with metritis may experience a greater degree of oxidative stress (OS) and a deficit in the antioxidative capacity compared to healthy cows. We aimed to assess circulating OS markers and endometrial cell mitochondrial function, intracellular reactive oxygen species (ROS) production, and mean endometrial nuclear cell area in postpartum cows diagnosed with metritis or as healthy. From an initial pool of 121 Holstein cows, we retrospectively selected 34 cows and balanced for metritis (n = 17) or healthy (n = 17). Metritis was defined as an enlarged uterus with red-brown watery or thick off-white purulent discharge occurring within 21 days postpartum. Cows with no signs of clinical disease (including dystocia or retained placenta) were referred to as healthy. Blood samples for serum reactive oxygen metabolites (d-ROM), antioxidants (OXY), and oxidative status index (OSI) tests, evaluated via photometric determination of plasma thiols, were performed at 7, 14, 21, 28, and 35 days postpartum. Furthermore, from the initial pool, a random subset of 5 cows diagnosed with metritis and 6 diagnosed as healthy we collected (at the same time points as for the blood samples) endometrial cytology samples using the cytobrush technique. From the uterine samples, we evaluated the endometrial cell mitochondrial function, intracellular ROS levels, and the endometrial cell nuclear area using MitoTracker Orange, dichlorodihydrofluorescein diacetate, and Hoechst 33258, respectively. Mixed linear regression models, accounting for repeated measurements, were fitted to assess the effect of metritis versus healthy on circulating and endometrial cell OS parameters and endometrial cell size. The effect of days postpartum and its interaction with uterine health status were forced into each model. Serum concentrations of d-ROMs and OSI were greater in metritis at 7, 14, and 35 days postpartum than in healthy cows. Interestingly, the mean endometrial cell nuclear area was lower in metritis than healthy cows at 14 and 21 days postpartum. We found no differences between metritis and healthy for endometrial cell mitochondrial function and intracellular ROS production. In conclusion, cows diagnosed with metritis experienced greater systemic OS levels than healthy cows, but their OS was not higher in the uterine milieu.


Assuntos
Doenças dos Bovinos , Endometrite , Gravidez , Feminino , Bovinos , Animais , Endometrite/veterinária , Lactação , Espécies Reativas de Oxigênio , Estudos Retrospectivos , Doenças dos Bovinos/diagnóstico , Período Pós-Parto , Antioxidantes/metabolismo , Estresse Oxidativo
5.
Animals (Basel) ; 12(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36428406

RESUMO

The purpose of this study was to determine the effect on fresh and post-thaw beef bull semen quality of the supplementation of epidermal growth factor (EGF) to the semen extender at various concentrations (0-control, 50, 100, 200, and 400 ng/mL). For 8 weeks, sperm was collected from four fertile bulls, yielding a total of 32 ejaculates. Semen samples were pooled, diluted with Bullxcell® extender, and then cooled, equilibrated, and frozen. After thawing, semen was tested for motility and velocity parameters. Furthermore, semen was evaluated for vitality, integrity, mitochondrial and antioxidant (SOD) activities, mucus penetration distance, and in vitro fertilizing capability. The supplementation with EGF prior to cryopreservation improved the total sperm motility at various concentrations over long incubation periods (from 1 to 4 h). Interestingly, EGF addition improved both progressive and rapid motility, particularly at 50, 200, and 400 ng/mL. In addition, EGF, primarily at 200 and 400 ng/mL, significantly increased several velocity parameters after different incubation periods. We can conclude that adding EGF to bull sperm extender before cryopreservation has a positive stimulatory effect on sperm motility without affecting vitality, integrity, or in vitro fertilizing capability.

6.
Theriogenology ; 192: 141-149, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36099804

RESUMO

This work aimed to determine the effect of cysteamine (25, 50, 100 and 200 µM) incorporated during dilution on frozen thawed buffalo semen quality. Semen was collected twice weekly for 7 consecutive weeks from three Egyptian buffalo bulls using an artificial vagina. Semen samples were pooled and extended with a Tris-based extender, cooled, equilibrated and finally frozen in liquid nitrogen. The diluted semen was evaluated for motility, viability, morphology, plasma membrane and DNA integrity, in addition to oxidative stress and in vitro fertilizing capability. The post thaw motility and velocity parameters noticeably increased with different concentrations of cysteamine (mainly 100 µM) during different incubation periods. The post thaw sperm viability and normality significantly (p < 0.05) improved with concentrations of 50 and 100 µM. Plasma membrane integrity substantially increased at all concentrations of cysteamine. Cysteamine reduced alanine aminotransferase (at all concentrations), aspartate aminotransferase (at 25-100 µM), and creatine kinase (at 100 and 200 µM). Cysteamine at a concentration of 100 µM noticeably enhanced the total antioxidant capacity and glutathione peroxidase and decreased nitric oxide production. Cysteamine, at concentrations of 100 and 200 µM, increased the DNA intensity in the comet head (%) and decreased the DNA % in the comet tail. The comet tail length and moment substantially decreased at concentrations of 50-200 µM. Cysteamine did not affect the in vitro fertilizing capability of sperm. In conclusion, cysteamine incorporation (mainly at a concentration of 100 µM) in buffalo semen extender showed varying protective effects on different sperm parameters against cryo-damage; however, it did not affect the in vitro fertilizing capacity of sperm.


Assuntos
Bison , Preservação do Sêmen , Alanina Transaminase , Animais , Antioxidantes/farmacologia , Aspartato Aminotransferases , Búfalos , Creatina Quinase , Criopreservação/veterinária , Crioprotetores/farmacologia , Cisteamina/farmacologia , Suplementos Nutricionais , Feminino , Glutationa Peroxidase , Masculino , Óxido Nítrico , Nitrogênio/farmacologia , Sêmen , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
7.
Cryobiology ; 95: 51-59, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32561273

RESUMO

This study aimed to improve the quality of cryopreserved beef bull (Piedmontese) semen by incorporation of relaxin in diluted semen before cryopreservation procedures. Semen samples were collected from 4 proven fertile bulls, using artificial vagina, once per week for 8 consecutive weeks and pooled together then diluted with Bullxcell® extender, and supplemented with different concentrations of relaxin (0 (control), 25, 50 and 100 ng/ml) before cooling, equilibration and freezing procedures. Frozen semen was thawed and assessed for motility by Computer-Assisted Sperm Analysis and vitality parameters such as acrosome, plasma membrane and DNA integrities, apoptosis, mitochondrial membrane potential, mucus penetration and SOD activity. The developmental potential of bovine embryos produced in vitro by using relaxin-treated was also investigated. In the present study, 50 and 100 ng/ml relaxin incorporation in extended bull semen before cryopreservation induced a reduction of sperm motility immediately after thawing (0h), whereas, during long incubation periods (1-2 h), relaxin showed a significant positive effect on sperm quality by improving the sperm motility and velocity parameters. Interestingly, sperm vitality was improved by 25 and 100 ng/ml relaxin and the blastocyst developmental rate was significantly increased in the 25 ng/ml relaxin group compared with controls (52/118, 44.0% vs. 32/116, 27.6%, respectively). These findings suggest a potential use of relaxin at the doses tested in the present study as an additive in the cryopreservation media of bull semen to improve sperm quality.


Assuntos
Relaxina , Preservação do Sêmen , Animais , Bovinos , Criopreservação/métodos , Feminino , Humanos , Masculino , Relaxina/farmacologia , Sêmen , Análise do Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
8.
Anim Reprod Sci ; 216: 106351, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32414467

RESUMO

The aim of the study was to ascertain effects of different concentrations of relaxin added to extender medium during the pre-freezing incubation periods on quality variables of stallion frozen-thawed spermatozoa. Semen samples collected from three stallions were filtered, diluted with skim milk, and centrifuged at 600g for 10 min. Sperm pellets were suspended in BotuCrio freezing medium to a final concentration of 50 × 106 sperm/mL. The diluted semen was divided into five experimental groups supplemented with 0 (control), 12.5, 25, 50, or 100 ng/mL of relaxin. The semen samples were transferred into 0.5 mL straws, equilibrated at 5 °C for 30 min, and placed in liquid nitrogen (LN2) vapour for 15 min before being plunged into LN2. After thawing, sperm samples were evaluated for motility and velocity variables, mitochondrial membrane potential, apoptosis, and plasma membrane and DNA integrities. For sperm motility variables, there were dose- and time-dependent effects, with the largest values recorded when 12.5 and 25 ng/mL relaxin were used for 0-120 min of incubation. Furthermore, at all of the concentrations at which there were evaluations, relaxin additions to semen diluent led to a marked improvement in sperm mitochondrial membrane potential and a lesser percentage of apoptotic cells compared to the control group. Plasma membranes and DNA integrities were not affected by relaxin supplementations to the diluent. In conclusion, supplementation of relaxin in extender before semen cryopreservation, especially at 12.5 and 25 ng/mL, had a positive effect on the sperm quality variables.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cavalos/fisiologia , Relaxina/farmacologia , Sêmen/fisiologia , Animais , Membrana Celular , Dano ao DNA , Congelamento , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
9.
Theriogenology ; 126: 95-105, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30544000

RESUMO

The aim of this study was to collect and analyze ultrasound measurements of fetal-maternal structures during normal and pathological pregnancies in jennies, a livestock species of growing interest. For two breeding seasons, 38 jennies of different breeds and crossbreeds aged between 3 and 18 years were monitored weekly by transrectal examination using a portable Esaote ultrasound (MyLab™ 30 GOLD VET) with a 5-7.5 MHz probe. The jennies were divided into two groups, < 250 kg and >250 kg body weight, and the dates of conception and parturition/abortion were recorded to calculate pregnancy length. Descriptive statistics were performed for the following variables: pregnancy length and maternal-fetal parameters (measurements of the orbit, gastric bubble, thorax, abdomen, gonads, heart rate, umbilical artery velocimetry, and combined utero-placental thickness). A total of 68 pregnancies were studied, 36 of which ended during the study period. The average pregnancy length was 370.82 ± 16.6 days for full-term pregnancies (N = 28, 77.8%) and 316.13 ± 36.6 days for abortions (N = 8, 22.2%). The season of conception and fetal gender did not affect the pregnancy length. Pregnancy examination can reasonably be performed by two weeks after last service if ovulation date is not known. The orbital diameter was the most reliable parameter for monitoring the physiological development of the embryo and fetus, and it was strongly related to the gestational age. No differences in fetal development were observed in relation to the mother's body weight. The combined utero-placental thickness was not associated with the gestational age and thickening and edema, frequently observed, were not associated with fetal pathologies.


Assuntos
Equidae/fisiologia , Desenvolvimento Fetal , Feto/diagnóstico por imagem , Prenhez , Ultrassonografia Pré-Natal/veterinária , Animais , Peso Corporal , Feminino , Idade Gestacional , Gravidez , Útero/diagnóstico por imagem
10.
Theriogenology ; 89: 338-347, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28341078

RESUMO

Extrafetal tissues are a noncontroversial and inexhaustible source of mesenchymal stem cells that can be harvested noninvasively at low cost. In the veterinary field, as in man, stem cells derived from extrafetal tissues express plasticity, reduced immunogenicity, and have high anti-inflammatory potential making them promising candidates for treatment of many diseases. Umbilical cord mesenchymal cells have been isolated and characterized in different species and have recently been investigated as potential candidates in regenerative medicine. In this study, cells derived from bovine Wharton jelly (WJ) were isolated for the first time by enzymatic methods, frozen/thawed, cultivated for at least 10 passages, and characterized. Wharton jelly-derived cells readily attached to plastic culture dishes displaying typical fibroblast-like morphology and, although their proliferative capacity decreased to the seventh passage, these cells showed a mean doubling time of 34.55 ± 6.33 hours and a mean frequency of one colony-forming unit fibroblast like for every 221.68 plated cells. The results of molecular biology studies and flow cytometry analyses revealed that WJ-derived cells showed the typical antigen profile of mesenchymal stem cells and were positive for CD29, CD44, CD105, CD166, Oct-4, and c-Myc. They were negative for CD34 and CD14. Remarkably, WJ-derived cells showed differentiation ability. After culture in induced media, WJ-derived cells were able to differentiate into osteogenic, adipogenic, chondrogenic, and neurogenic lines as shown by positive staining and expression of specific markers. On polymerase chain reaction analysis, these cells were negative for MHC-II and positive for MHC-I, thus reinforcing the role of extrafetal tissue as an allogenic source for bovine cell-based therapies. These results provide evidence that bovine WJ-derived cells may have the potential to differentiate to repair damaged tissues and reinforce the importance of extrafetal tissues as stem cell sources in veterinary regenerative medicine. A more detailed evaluation of their immunologic properties is necessary to better understand their potential role in cellular therapy.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Geleia de Wharton/citologia , Animais , Bovinos , Técnicas de Cultura de Células/veterinária , Proliferação de Células , Citometria de Fluxo/veterinária
11.
Anim Reprod Sci ; 98(3-4): 350-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16621352

RESUMO

Bovine infertility is a major cause of loss in the livestock industry. In the present study bovine oviduct cell cultures were infected with a Chlamydophila abortus strain. A direct evaluation of infection was performed by means of May Grünwald-Giemsa and immunocytochemistry for chlamydial LPS, which revealed inclusion bodies and vacuolisation. SEM and TEM analysis of infected cells showed various degrees of cell damage and conglutination of microvilli. This finding suggests that cattle infertility may result from an alteration of oviduct environment caused by multiplication of C. abortus. This microorganism, among other infectious agents, could be considered a potential causative agent of bovine infertility.


Assuntos
Doenças dos Bovinos , Infecções por Chlamydophila/veterinária , Chlamydophila , Infertilidade/veterinária , Oviductos/microbiologia , Animais , Bovinos , Doenças dos Bovinos/patologia , Células Cultivadas , Infecções por Chlamydophila/patologia , Células Epiteliais/microbiologia , Feminino , Lipopolissacarídeos/análise , Oviductos/citologia
12.
Reprod Nutr Dev ; 42(3): 217-26, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12405450

RESUMO

The aims of this study were to compare glycerol (G) at customary concentrations and ethylene glycol (EG) as cryoprotectants for stallion semen in a skimmed milk (SM) extender, to test different EG concentrations and to compare the results of manual and computerized analysis with the hypoosmotic swelling (HOS) test. Ejaculates from two stallions were collected over 3 weeks (6 ejaculates per stallion), diluted in a SM based extender, divided into 4 fractions, centrifuged and diluted again to a concentration of 100 x 10(6) mL(-1) progressive motile spermatozoa (PMS) in addition with the cryoprotectant (3% G, 3% EG, 6% EG, 9% EG). Sperm motility was assessed both by microscopy (in raw and frozen-thawed semen immediately after thawing) and with an HTM-IVOS analyzer (Hamilton-Thorne Research, MA, USA), at 0, 1, 4, 6, and 12 h after thawing and storage at 21 degrees C. Raw and frozen-thawed (0 h) semen samples for G and EG at 3% were also submitted to the HOS test with a 100 mOsm sucrose solution and were evaluated to detect the presence of swollen tails. The higher EG concentrations (i.e. 6% EG and 9% EG) significantly reduced the percentage of motile and PMS, immediately after thawing. At the same concentration, i.e. 3%, G resulted in a higher percentage of PMS than EG (36.2 vs. 30%, P < 0.05), but at 12 h after thawing and storage at 21 degrees C, no significant differences were detected between G and EG at 3%. The correlations between progressive motility (assessed by direct microscope observation or measured through the HTM analyzer) and the HOS test results for 3%G and EG were r = 0.61 and r = 0.35, respectively. The HOS test confirmed its suitability as a complementary method of analysis for stallion semen. We conclude that with the SM extender used, EG could substitute G as the cryoprotectant for stallion semen if used at the same or lower concentration.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cavalos/fisiologia , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Animais , Criopreservação/métodos , Criopreservação/normas , Etilenoglicol/farmacologia , Glicerol/farmacologia , Masculino , Concentração Osmolar , Sêmen/efeitos dos fármacos , Preservação do Sêmen/métodos , Preservação do Sêmen/normas , Motilidade dos Espermatozoides , Espermatozoides , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...