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1.
J Assist Reprod Genet ; 41(5): 1357-1370, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38438770

RESUMEN

PURPOSE: This study aimed to identify a marker for freezability and in vitro fertility of sperm samples before freezing. METHODS: Semen was collected from nine Nelore bulls; half of the ejaculate was used for seminal plasma cell-free DNA (cfDNA) quantification, and the other half was cryopreserved. Evaluation of sperm movement using computer-assisted semen analysis and plasma membrane integrity and stability, acrosomal integrity, apoptosis, and mitochondrial potential using flow cytometry were performed on fresh and frozen/thawed semen at 0, 3, 6, and 12 h after thawing. Frozen/thawed sperm was also used for in vitro embryo production. cfDNA was extracted from each bull, and the total DNA and number of cell-free mitochondrial DNA (cfmtDNA) copies were quantified. Semen from each animal was used for IVF, and cleavage, blastocyst formation, and cell counts were evaluated. RESULTS: Two groups were formed and compared based on the concentrations of cfDNA and cfmDNA present: low-cfDNA and high-cfDNA and low-cfmtDNA and high-cfmtDNA. Up to 12 h post-thawing, there were no differences between the groups in the majority of the sperm parameters evaluated. Cleavage, day 6 and 7 blastocyst rates, and the number of cells were higher in the high cfDNA group than in the low cfDNA group. Similar results were observed for cfmtDNA, except for the number of cells, which was similar between the groups. CONCLUSION: The concentration of cfDNA and the relative number of copies of cfmtDNA in seminal plasma cannot predict the freezability of semen but can be used to predict in vitro embryo production.


Asunto(s)
Ácidos Nucleicos Libres de Células , Criopreservación , Fertilización In Vitro , Análisis de Semen , Preservación de Semen , Semen , Motilidad Espermática , Espermatozoides , Animales , Masculino , Bovinos , Ácidos Nucleicos Libres de Células/genética , Ácidos Nucleicos Libres de Células/sangre , Fertilización In Vitro/veterinaria , Criopreservación/veterinaria , Semen/metabolismo , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Motilidad Espermática/genética , Fertilidad/genética , Biomarcadores , ADN Mitocondrial/genética , Blastocisto/metabolismo
2.
Anim Reprod Sci ; 211: 106226, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31785634

RESUMEN

The aim of this study was to evaluate effects of intra-follicular (i.f.) treatment with lipopolysaccharide (LPS) on follicular and luteal development in cows. There were 18 non-lactating cows assigned to two groups to address this aim: control group (n = 9), which received an i.f. injection of saline; and LPS group (n = 9), which received an i.f. injection of 1 µg of LPS per mL of follicular fluid. Cows were treated with an intravaginal P4 releasing device (IVD) and estradiol benzoate on D0. On D4 and D5 cows were treated with cloprostenol sodium and on D7 the IVD was removed. At 12 h after IVD removal, cows were administered the i.f. injection of LPS or saline. After administration of these treatments, follicular development was evaluated every 12 h until ovulation. The LPS treatment increased blood flow in pre-ovulatory follicles (P = 0.05). Follicle growth was reduced by LPS injection (P < 0.02) resulting a longer period to the time of ovulation for cows in the LPS than control group (P = 0.03). The percentage of cows having ovulations was less for the LPS than control group (P = 0.03). The diameter of the CL, CL blood flow and P4 concentrations 5 and 12 days after ovulation did not differ between groups (P> 0.05). In conclusion, intra-follicular treatment with LPS resulted in a decreased rate of follicle growth, delayed timing of ovulations and a lesser number of cows having ovulations.


Asunto(s)
Bovinos , Lipopolisacáridos/toxicidad , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Animales , Femenino , Inyecciones , Progesterona/sangre
3.
Reproduction ; 158(5): 453-463, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31546231

RESUMEN

The aim of this study was to evaluate the effect of exposing bovine oocytes to lipopolysaccharides (LPS) in vivo and in vitro on early embryo development. In experiment 1, cumulus oocyte complexes (COCs, n = 700/group) were challenged with 0, 0.1, 1.0 or 5.0 µg/mL of LPS during in vitro maturation (IVM). Later, in vitro fertilization (IVF) and in vitro culture (IVC) were performed. In experiment 2, COCs (n = 200/group) matured and in vitro fertilized without LPS were subjected to IVC with the same doses of LPS from experiment 1. In experiment 3, heifers received two injections of saline solution (n = 8) or 0.5 µg/kg of LPS (n = 8) 24 h apart, and 3 days later, COCs were recovered and submitted to IVM, IVF, and IVC. In experiments 1 and 3, the expression of TLR4, TNF, AREG and EREG genes in cumulus cells was evaluated. Exposure to 1 and 5 µg/mL of LPS during IVM decreased nuclear maturation (39.4 and 39.6%, respectively) compared with control (63.6%, P < 0.05). Despite that, no effect on cleavage and blastocyst rates were observed. Exposure to LPS during IVC did not affect embryonic development. In vivo exposure to LPS decreased the in vitro cleavage rate (54.3 vs 70.2%, P = 0.032), but cleaved embryos developed normally. Number of cells per embryo and gene expression were not affected by the LPS challenge in any experiment. In conclusion, although in vitro exposure to LPS did not affect early embryo development, in vivo LPS exposure reduced cleavage rate.


Asunto(s)
Desarrollo Embrionario/efectos de los fármacos , Lipopolisacáridos/farmacología , Oocitos/efectos de los fármacos , Animales , Blastocisto/citología , Blastocisto/efectos de los fármacos , Blastocisto/fisiología , Bovinos , Células Cultivadas , Fase de Segmentación del Huevo/efectos de los fármacos , Fase de Segmentación del Huevo/fisiología , Células del Cúmulo/citología , Células del Cúmulo/efectos de los fármacos , Células del Cúmulo/fisiología , Técnicas de Cultivo de Embriones/veterinaria , Embrión de Mamíferos , Femenino , Fertilización In Vitro/veterinaria , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/citología , Oocitos/fisiología , Embarazo
4.
Reprod Domest Anim ; 54(3): 445-455, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30417448

RESUMEN

High-density lipoprotein (HDL) is the main lipoprotein in the follicular fluid, and it has anti-inflammatory, antioxidant and cryoprotectant properties. The anti-inflammatory potential and antioxidant potential are derived from its lipid composition, especially the apolipoprotein AI (ApoAI) and paraoxonase 1 (PON1). The aim of this study was to evaluate the effect of HDL during in vitro maturation (IVM) on oocyte maturation and early bovine embryo development. For this, cumulus-oocyte complexes (COCs) were obtained from bovine ovaries collected at a local slaughterhouse. COCs (n = 2,250) were allocated into three groups (n = 50 COCs/group) according to the addition of HDL protein (HDL-P) during IVM for 22 hr: 0 (control), 50 and 150 mg/dl. After IVM, COCs were inseminated (in vitro fertilization) and cultivated for 7 days. Total cholesterol concentration, total protein, triglycerides and ApoAI concentrations on IVM medium increased proportionally to HDL-P addition. However, PON1 activity was not detected in any treatment. The addition of HDL-P did not affect nuclear maturation rate, endogenous reactive oxygen species and glutathione levels in COCs (p > 0.05). The highest HDL-P concentration (150 mg/dl) decreased cleavage and blastocyst rate (p < 0.05). Moreover, the HDL-P 150 mg/dl group had lower cellular count/blastocyst than the 50 mg/dl group (p < 0.05). However, the addition of HDL-P did not affect relative gene expression of evaluated genes. In conclusion, the complex HDL/ApoAI obtained from human plasma, in the absence of PON1 activity during in vitro oocyte maturation, decreased initial embryo development.


Asunto(s)
Blastocisto/fisiología , Técnicas de Cultivo de Embriones/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Lipoproteínas HDL/farmacología , Oocitos/crecimiento & desarrollo , Animales , Apolipoproteína A-I/farmacología , Arildialquilfosfatasa/farmacología , Bovinos , Células del Cúmulo/efectos de los fármacos , Femenino , Fertilización In Vitro/veterinaria , Expresión Génica , Humanos , Oogénesis
5.
Anim Reprod ; 16(4): 914-922, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-32368271

RESUMEN

The aim of this study was to evaluate the long-term effects of recombinant bovine somatotropin (rbST) on follicle population and ovulatory follicle development in non-lactating dairy cows. Twenty-one Jersey cows were allocated in rbST (n=11) or control (n=10) groups. On day -60, cows in rbST group received 500 mg of somatotropin (s.c. Lactotropin®, Elanco). On day 0, control and rbST cows received an intravaginal progesterone-releasing device (1.9 g, CIDR®, Zoetis) and GnRH (100 mg, IM, Factrel®, Zoetis). On day 8, cows received PGF2α (25 mg, IM, Lutalyse®, Zoetis) and the CIDR® was removed. Twelve hours after device removal (D8), serum, follicular fluid and granulosa cells samples were collected. Serum and follicular concentration of estradiol (E2) and progesterone (P4) were analyzed. Total RNA was extracted from granulosa cells to measure gene expression of LHCGR, STAR, HSD-3B1, CYP11A1, CYP19A1, CYP17A1, IGFR and PAPPA by real-time PCR. Ultrasonography was performed on days -60, -53, -46, -14, -7, 0 and 8 for antral follicle count. Results were analyzed by repeated measures ANOVA and t-test. There was no effect of rbST treatment on the number of follicles during the 60 days period, as well as no effect on serum and follicular fluid E2 and follicular fluid P4 at the moment of follicle aspiration. There was a reduction in PAPPA (P = 0.006), CYP11A1 (P = 0.04) and CYP19A1 (P = 0.002) mRNA levels in granulosa cells of the pre-ovulatory follicle of rbST treated cows. In conclusion, a single dose of rbST did not have long-term effects on antral follicle population, serum and follicular E2/P4 concentrations in non-lactating dairy cows. Despite that, rbST injection decreased granulosa cell expression of genes related to steroidogenesis in the pre-ovulatory follicle.

6.
Anim. Reprod. (Online) ; 16(4): 914-922, 2019. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1461478

RESUMEN

The aim of this study was to evaluate the long-term effects of recombinant bovine somatotropin (rbST) on follicle population and ovulatory follicle development in non-lactating dairy cows. Twenty-one Jersey cows were allocated in rbST (n=11) or control (n=10) groups. On day -60, cows in rbST group received 500 mg of somatotropin (s.c. Lactotropin®, Elanco). On day 0, control and rbST cows received an intravaginal progesterone-releasing device (1.9 g, CIDR®, Zoetis) and GnRH (100 mg, IM, Factrel®, Zoetis). On day 8, cows received PGF2α (25 mg, IM, Lutalyse®, Zoetis) and the CIDR® was removed. Twelve hours after device removal (D8), serum, follicular fluid and granulosa cells samples were collected. Serum and follicular concentration of estradiol (E2) and progesterone (P4) were analyzed. Total RNA was extracted from granulosa cells to measure gene expression of LHCGR, STAR, HSD-3B1, CYP11A1, CYP19A1, CYP17A1, IGFR and PAPPA by real-time PCR. Ultrasonography was performed on days -60, -53, -46, -14, -7, 0 and 8 for antral follicle count. Results were analyzed by repeated measures ANOVA and t-test. There was no effect of rbST treatment on the number of follicles during the 60 days period, as well as no effect on serum and follicular fluid E2 and follicular fluid P4 at the moment of follicle aspiration. There was a reduction in PAPPA (P = 0.006), CYP11A1 (P = 0.04) and CYP19A1 (P = 0.002) mRNA levels in granulosa cells of the pre-ovulatory follicle of rbST treated cows. In conclusion, a single dose of rbST did not have long-term effects on antral follicle population, serum and follicular E2/P4 concentrations in non-lactating dairy cows. Despite that, rbST injection decreased granulosa cell expression of genes related to steroidogenesis in the pre-ovulatory follicle.


Asunto(s)
Femenino , Animales , Bovinos , Bovinos/genética , Expresión Génica , Hormona del Crecimiento/análisis , Hormona del Crecimiento/efectos adversos , Fase Folicular
7.
Anim. Reprod. ; 16(4): 914-922, 2019. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-24190

RESUMEN

The aim of this study was to evaluate the long-term effects of recombinant bovine somatotropin (rbST) on follicle population and ovulatory follicle development in non-lactating dairy cows. Twenty-one Jersey cows were allocated in rbST (n=11) or control (n=10) groups. On day -60, cows in rbST group received 500 mg of somatotropin (s.c. Lactotropin®, Elanco). On day 0, control and rbST cows received an intravaginal progesterone-releasing device (1.9 g, CIDR®, Zoetis) and GnRH (100 mg, IM, Factrel®, Zoetis). On day 8, cows received PGF2α (25 mg, IM, Lutalyse®, Zoetis) and the CIDR® was removed. Twelve hours after device removal (D8), serum, follicular fluid and granulosa cells samples were collected. Serum and follicular concentration of estradiol (E2) and progesterone (P4) were analyzed. Total RNA was extracted from granulosa cells to measure gene expression of LHCGR, STAR, HSD-3B1, CYP11A1, CYP19A1, CYP17A1, IGFR and PAPPA by real-time PCR. Ultrasonography was performed on days -60, -53, -46, -14, -7, 0 and 8 for antral follicle count. Results were analyzed by repeated measures ANOVA and t-test. There was no effect of rbST treatment on the number of follicles during the 60 days period, as well as no effect on serum and follicular fluid E2 and follicular fluid P4 at the moment of follicle aspiration. There was a reduction in PAPPA (P = 0.006), CYP11A1 (P = 0.04) and CYP19A1 (P = 0.002) mRNA levels in granulosa cells of the pre-ovulatory follicle of rbST treated cows. In conclusion, a single dose of rbST did not have long-term effects on antral follicle population, serum and follicular E2/P4 concentrations in non-lactating dairy cows. Despite that, rbST injection decreased granulosa cell expression of genes related to steroidogenesis in the pre-ovulatory follicle.(AU)


Asunto(s)
Animales , Femenino , Bovinos , Bovinos/genética , Hormona del Crecimiento/efectos adversos , Hormona del Crecimiento/análisis , Expresión Génica , Fase Folicular
8.
Ci. Rural ; 48(7): e20170921, July.2018. tab
Artículo en Inglés | VETINDEX | ID: vti-736309

RESUMEN

The aim of this study was to estimate neosporosis seroprevalence and its associated risk factors in milk herds (Bos taurus taurus) located in the northwestern region of Rio Grande do Sul State, Brazil. Three hundred twenty-two blood samples were collected from dairy cows on 18 farms in 17 cities of this region. An epidemiologic questionnaire was completed for each farm. It consisted of questions about the general characteristics of the herd, reproduction, and animal management. Serum samples were tested for Neospora caninum using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Results indicated a seroprevalence of Neospora in 88.9% (16/18) of herds and 31.1% (100/322) of individuals. Risk factor analyses demonstrated that culling by reproductive disorder (OR = 0.6), flooding (OR = 0.5), and commercial sale (OR = 0.4) were associated with seroprevalence. Nevertheless, the purchase of replacement animals in the herd played an important role in disease occurrence (OR = 2.2). Results of this study suggested that Neospora caninum was present in the studied herds under investigation and that there are risk factors associated with its seroprevalence on the farms of the northwestern of Rio Grande do Sul.(AU)


O objetivo desse estudo foi estimar a soroprevalência da neosporose e os possíveis fatores de risco em rebanhos (Bos taurus taurus) localizados na mesorregião Noroeste do Rio Grande do Sul, Brasil. Foram coletadas 322 amostras de sangue de bovinos leiteiros, em 18 propriedades localizadas em 17 munícipios desta mesorregião. Um questionário epidemiológico foi aplicado em cada propriedade, contendo questões relacionadas às características gerais dos rebanhos, dados reprodutivos e manejo animal. As amostras de soro foram testadas através do teste de imunoensaio enzimático (ELISA) para Neospora caninum. Os resultados demonstraram uma soroprevalência de Neospora de 88,9% (16/18) entre os rebanhos e 31,1% (100/322) entre os indivíduos. Entre os fatores de risco analisados foi observado que descarte por problemas reprodutivos (OR=0,6), presença de áreas alagadiças (OR=0,5) e venda comercial (OR=0,4) estavam associados a soroprevalência. No entanto, a compra de animais substituídos no rebanho desempenhou um papel significativo na ocorrência da doença (OR=2,2). Os resultados desse estudo sugerem que o Neospora caninum esteve presente nos rebanhos estudados, bem como, existem fatores associados com a soroprevalência nas propriedades da mesorregião do Noroeste do Rio Grande do Sul.(AU)


Asunto(s)
Animales , Bovinos , Neospora/aislamiento & purificación , Coccidiosis/epidemiología , Coccidiosis/veterinaria , Factores de Riesgo , Brasil
9.
Ciênc. rural (Online) ; 48(7): e20170921, 2018. tab
Artículo en Inglés | LILACS | ID: biblio-1045174

RESUMEN

ABSTRACT: The aim of this study was to estimate neosporosis seroprevalence and its associated risk factors in milk herds (Bos taurus taurus) located in the northwestern region of Rio Grande do Sul State, Brazil. Three hundred twenty-two blood samples were collected from dairy cows on 18 farms in 17 cities of this region. An epidemiologic questionnaire was completed for each farm. It consisted of questions about the general characteristics of the herd, reproduction, and animal management. Serum samples were tested for Neospora caninum using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Results indicated a seroprevalence of Neospora in 88.9% (16/18) of herds and 31.1% (100/322) of individuals. Risk factor analyses demonstrated that culling by reproductive disorder (OR = 0.6), flooding (OR = 0.5), and commercial sale (OR = 0.4) were associated with seroprevalence. Nevertheless, the purchase of replacement animals in the herd played an important role in disease occurrence (OR = 2.2). Results of this study suggested that Neospora caninum was present in the studied herds under investigation and that there are risk factors associated with its seroprevalence on the farms of the northwestern of Rio Grande do Sul.


RESUMO: O objetivo desse estudo foi estimar a soroprevalência da neosporose e os possíveis fatores de risco em rebanhos (Bos taurus taurus) localizados na mesorregião Noroeste do Rio Grande do Sul, Brasil. Foram coletadas 322 amostras de sangue de bovinos leiteiros, em 18 propriedades localizadas em 17 munícipios desta mesorregião. Um questionário epidemiológico foi aplicado em cada propriedade, contendo questões relacionadas às características gerais dos rebanhos, dados reprodutivos e manejo animal. As amostras de soro foram testadas através do teste de imunoensaio enzimático (ELISA) para Neospora caninum. Os resultados demonstraram uma soroprevalência de Neospora de 88,9% (16/18) entre os rebanhos e 31,1% (100/322) entre os indivíduos. Entre os fatores de risco analisados foi observado que descarte por problemas reprodutivos (OR=0,6), presença de áreas alagadiças (OR=0,5) e venda comercial (OR=0,4) estavam associados a soroprevalência. No entanto, a compra de animais substituídos no rebanho desempenhou um papel significativo na ocorrência da doença (OR=2,2). Os resultados desse estudo sugerem que o Neospora caninum esteve presente nos rebanhos estudados, bem como, existem fatores associados com a soroprevalência nas propriedades da mesorregião do Noroeste do Rio Grande do Sul.

10.
Zygote ; 25(1): 49-55, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27955714

RESUMEN

Staining with brilliant cresyl blue (BCB) may be used for oocyte selection, but BCB staining itself and the most commonly used selection medium (DMPBS) may compromise the development of porcine oocytes in vitro. This study evaluated DNA fragmentation, nuclear maturation, the area of migration of cortical granules (CG) and embryo development for stained (BCB+) and unstained (BCB-) oocytes incubated in DMPBS and in a modified medium (ReproPel) tested for the first time. Unexposed (UN), BCB+ and BCB- oocytes were incubated composing six groups: DMPBS/UN; DMPBS/BCB+; DMPBS/BCB-; ReproPel/UN; ReproPel/BCB+; and ReproPel/BCB-. There were more BCB+ oocytes in ReproPel than in DMPBS (P < 0.05). The DNA fragmentation was evaluated for oocytes in DMPBS/BCB+, DMPBS/BCB-, ReproPel/BCB+, ReproPel/BCB- and in porcine follicular fluid (control). The frequency of oocytes with no DNA fragmentation was greatest (64.6%) in DMPBS/BCB+ and lowest in ReproPel/BCB+ and ReproPel/BCB- (26.8 and 34.1%, respectively) (P < 0.05). Nuclear maturation rates were greater (P < 0.05) for DMPBS/BCB+ (63.1%), ReproPel/UN (55.1%) and ReproPel/BCB+ (50.2%) than for DMPBS/UN (40.8%) and ReproPel/BCB- (35.5%). The area of CG was greater (P < 0.05) for ReproPel/BCB- (80.7%) and DMPBS/UN (77.6%) than for ReproPel/UN (34.7%). Cleavage rates for DMPBS/BCB+ and ReproPel/BCB+ were greater than for DMPBS/UN (P < 0.05). Blastocyst development rates were greatest (P < 0.05) for ReproPel/UN and ReproPel/BCB+. In both media, BCB staining was apparently unable to select competent oocytes, which likely occurred due to toxicity. Despite the similar nuclear maturation and area of CG compared with DMPBS, oocytes selected in ReproPel presented impaired DNA integrity.


Asunto(s)
Medios de Cultivo/química , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos/fisiología , Oxazinas , Animales , Blastocisto/citología , Células Cultivadas , Colorantes , Fragmentación del ADN , Femenino , Pruebas de Mutagenicidad/métodos , Oocitos/citología , Partenogénesis , Porcinos
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