Effect of oral drenching of glycerin as a source of pre-mating energetic supplementation on reproductive response in goats

The availability of glycerol has increased because of the biofuels industry, and glycerol can have a significant effect on reproductive efficiency when used as an alternative energy source in animal feeds. The aim of this study was to investigate the effects of pre-mating oral drenching of glycerin on ovarian and fertility responses in goats. Sixty Anglonubian mixed-breed goats were submitted to estrus synchronization by CIDR-prostaglandin PGF2α treatment and mated. At CIDR removal, onset of estrus, and 24 h after estrus behavior, the animals received 150 ml of saline solution (control group, n = 20), 150 ml of glycerol (150 ml group, n = 20), or 300 ml of glycerol (300 ml group, n = 20). The administration of glycerin increased plasma glucose in the 300 ml group (P < 0.05) and the insulin concentration at 12 h after glycerin drenching in both treated groups. Goats from the 300 ml group showed a lower ovulation rate when compared to the control group (1.15 ± 0.08 vs. 0.89 ± 0.14; P < 0.05) but exhibited larger follicles at 48, 24, and 12 h prior to ovulation (P < 0.05). Administration of 300 ml of glycerol was also associated with a significant reduction in the pregnancy rate (80.00% vs. 38.89%; P < 0.05) and in pregnant animals it was associated with lower growth of embryonic vesicles (1.78 ± 0.07 mm/day vs. 1.31 ± 0.07 mm/day; P < 0.05) compared to the control treatment. Gestational losses in the 300 ml group occurred between mating and the 45th day of pregnancy. No differences were found for the reproductive parameters analyzed in the study between the 150 ml and control groups. In conclusion, the supplementation with glycerol before the mating did not appear to be a viable alternative to increase reproductive efficiency of adult does.(AU)

Effect of oral drenching of glycerin as a source of pre-mating energetic supplementation on reproductive response in goats

The availability of glycerol has increased because of the biofuels industry, and glycerol can have a significant effect on reproductive efficiency when used as an alternative energy source in animal feeds. The aim of this study was to investigate the effects of pre-mating oral drenching of glycerin on ovarian and fertility responses in goats. Sixty Anglonubian mixed-breed goats were submitted to estrus synchronization by CIDR-prostaglandin PGF2α treatment and mated. At CIDR removal, onset of estrus, and 24 h after estrus behavior, the animals received 150 ml of saline solution (control group, n = 20), 150 ml of glycerol (150 ml group, n = 20), or 300 ml of glycerol (300 ml group, n = 20). The administration of glycerin increased plasma glucose in the 300 ml group (P < 0.05) and the insulin concentration at 12 h after glycerin drenching in both treated groups. Goats from the 300 ml group showed a lower ovulation rate when compared to the control group (1.15 ± 0.08 vs. 0.89 ± 0.14; P < 0.05) but exhibited larger follicles at 48, 24, and 12 h prior to ovulation (P < 0.05). Administration of 300 ml of glycerol was also associated with a significant reduction in the pregnancy rate (80.00% vs. 38.89%; P < 0.05) and in pregnant animals it was associated with lower growth of embryonic vesicles (1.78 ± 0.07 mm/day vs. 1.31 ± 0.07 mm/day; P < 0.05) compared to the control treatment. Gestational losses in the 300 ml group occurred between mating and the 45th day of pregnancy. No differences were found for the reproductive parameters analyzed in the study between the 150 ml and control groups. In conclusion, the supplementation with glycerol before the mating did not appear to be a viable alternative to increase reproductive efficiency of adult does.

Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.(AU)

Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.

Transforming growth factor-β (TGF-β) maintains follicular ultrastructure and stimulates preantral follicle growth in caprine ovarian tissue cultured in vitro / Fator de crescimento transformante-β (TGF-β) mantém a ultraestrutura folicular e estimula o crescimento de folículos pré-antrais caprinos inclusos em tecido ovariano cultivado in vitro

The objectives of this study were to investigate whether TGF-β affect the survival, activation and further growth of goat primordial follicles enclosed in ovarian cortex after in vitro culture. Goat ovaries were collected from an abattoir and pieces of ovarian tissues were cultured for one or seven days in a supplemented alpha Minimum Essential Medium, alone or containing TGF-β (1, 5, 10 or 50ng/mL). Ovarian tissues from the fresh control as well as those cultured were processed for histological and ultrastructural studies. The results showed that when compared with fresh control, there was decrease in the percentages of histologically normal follicles in all treatments only after seven days culture. TGF-β did not affect the activation of preantral follicles regardless of its concentration, however, larger follicles diameter (P<0.05) was observed using 10ng/mL TGF-β than in the fresh control and other treatments. Moreover, this concentration maintained the normal ultrastructure after seven days of culture. In conclusion, TGF-β showed additional effect on the follicle growth and the maintenance of ultrastructural integrity of goat preantral follicles enclosed in ovarian tissue when used at 10ng/mL during seven days of culture.(AU)

O objetivo desse estudo foi investigar se o TGF-β afeta a sobrevivência, ativação e crescimento de folículos primordiais caprinos inclusos no córtex ovariano após o cultivo in vitro. Ovários de cabras foram coletados em abatedouro e fragmentos de tecido ovariano foram cultivados por um e sete dias em meio essencial mínimo alfa (α-MEM+) sozinho ou suplementado com TGF-β (1, 5, 10 ou 50ng/mL). Fragmentos ovarianos não cultivados e cultivados foram processados para análise histológica e ultraestrutural. Os resultados mostraram que, comparado ao controle fresco, houve diminuição no percentual de folículos morfologicamente normais em todos os tratamentos somente após sete dias de cultivo. O TGF-β não afetou a ativação folicular independente da concentração testada, contudo, o diâmetro folicular foi superior (P<0.05) no tratamento com 10ng/mL de TGF-β quando comparado ao controle fresco e aos demais tratamentos. Além disso, essa mesma concentração manteve a ultraestrutura normal dos folículos após sete dias de cultivo. Em conclusão, o TGF-β apresentou efeito adicional no crescimento folicular e na manutenção da integridade ultraestrutural de folículos pré-antrais caprinos inclusos no tecido ovariano quando utilizado na concentração de 10ng/mL durante sete dias de cultivo.(AU)

Papel da Proteína Morfogenética Óssea 15 (BMP-15) e Kit Ligand (KL) na regulação da foliculogênese em mamíferos / Role of Bone Morphogenetic Protein 15 (BMP-15) and Kit Ligand (KL) in the regulation of folliculogenesis in mammalian

A foliculogênese é coordenada por diversos fatores de crescimento e hormônios responsáveis por garantir o sucesso do desenvolvimento folicular e oocitário. Para a obtenção de oócitos competentes, é necessária uma perfeita interação entre as células somáticas foliculares e o oócito, sendo esta potencialmente regulada por fatores parácrinos produzidos no ovário. Dentre estes fatores, destacam-se a BMP-15 e o KL, sintetizados pelo oócito e pelas células da granulosa, respectivamente. Este artigo revisa o importante papel da BMP-15 e do KL na foliculogênese, enfocando suas características, sítios de expressão, receptores e vias de sinalização, bem como a interação entre estas duas substâncias(AU)

Folliculogenesis is coordinated by many growth factors and hormones responsible for ensuring the success of follicular and oocyte development. To obtain competent oocytes is necessary to have a perfect interaction between follicular somatic cells and the oocyte, which is potentially regulated by paracrine factors produced in the ovary. Among these factors, we highlight BMP-15 and KL, synthesized by the oocyte and granulosa cells, respectively. This article reviews the important role of BMP-15 and KL in folliculogenesis, focusing on their characteristics, sites of expression, receptors and signaling pathways, as well as the interaction between these two substances(AU)

Papel da Proteína Morfogenética Óssea 15 (BMP-15) e Kit Ligand (KL) na regulação da foliculogênese em mamíferos / Role of Bone Morphogenetic Protein 15 (BMP-15) and Kit Ligand (KL) in the regulation of folliculogenesis in mammalian

A foliculogênese é coordenada por diversos fatores de crescimento e hormônios responsáveis por garantir o sucesso do desenvolvimento folicular e oocitário. Para a obtenção de oócitos competentes, é necessária uma perfeita interação entre as células somáticas foliculares e o oócito, sendo esta potencialmente regulada por fatores parácrinos produzidos no ovário. Dentre estes fatores, destacam-se a BMP-15 e o KL, sintetizados pelo oócito e pelas células da granulosa, respectivamente. Este artigo revisa o importante papel da BMP-15 e do KL na foliculogênese, enfocando suas características, sítios de expressão, receptores e vias de sinalização, bem como a interação entre estas duas substâncias

Folliculogenesis is coordinated by many growth factors and hormones responsible for ensuring the success of follicular and oocyte development. To obtain competent oocytes is necessary to have a perfect interaction between follicular somatic cells and the oocyte, which is potentially regulated by paracrine factors produced in the ovary. Among these factors, we highlight BMP-15 and KL, synthesized by the oocyte and granulosa cells, respectively. This article reviews the important role of BMP-15 and KL in folliculogenesis, focusing on their characteristics, sites of expression, receptors and signaling pathways, as well as the interaction between these two substances

Desenvolvimento e sobrevivência de embriões no período de pré-implantação: enfoque em ruminantes / Embryo development and survival during preimplantation period: focus in ruminants

O período de pré-implantação é considerado crítico para o desenvolvimento dos embriões em ruminantes, apresentando elevados índices de perda gestacional. Nesse período, uma série de eventos coordena o crescimento e a sobrevivência dos embriões, envolvendo a atuação de citocinas, esteroides, metabólitos e fatores de crescimento, responsáveis por garantir o sucesso da gestação e o subsequente desenvolvimento fetal. Esta revisão destacou os principais mecanismos e hormônios relacionados ao crescimento embrionário, utilizando os ruminantes como foco de estudo.(AU)

Preimplantation is considered a critical period for embryo development in ruminants, characterized by high pregnancy loss rates. In this period, many events coordinate the embryo growth and survival, involving cytokines, steroids, metabolites and growth factors, required to assure the pregnancy success and fetal development. This review aimed to highlight the major mechanisms and hormones related to embryo growth, using the ruminants as study focus.(AU)

Desenvolvimento e sobrevivência de embriões no período de pré-implantação: enfoque em ruminantes / Embryo development and survival during preimplantation period: focus in ruminants

O período de pré-implantação é considerado crítico para o desenvolvimento dos embriões em ruminantes, apresentando elevados índices de perda gestacional. Nesse período, uma série de eventos coordena o crescimento e a sobrevivência dos embriões, envolvendo a atuação de citocinas, esteroides, metabólitos e fatores de crescimento, responsáveis por garantir o sucesso da gestação e o subsequente desenvolvimento fetal. Esta revisão destacou os principais mecanismos e hormônios relacionados ao crescimento embrionário, utilizando os ruminantes como foco de estudo.

Preimplantation is considered a critical period for embryo development in ruminants, characterized by high pregnancy loss rates. In this period, many events coordinate the embryo growth and survival, involving cytokines, steroids, metabolites and growth factors, required to assure the pregnancy success and fetal development. This review aimed to highlight the major mechanisms and hormones related to embryo growth, using the ruminants as study focus.