PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Eigenheer-Moreira J.F., Fernandes F.T., Queiroz F.J.R, Pinho T.G.& Ferreira A.M.R. 2007. [Comparative study of repeat breeds and healthy mares through endometrial histology and plasmatic progesterone concentrations.] Estudo comparativo de éguas repetidoras ou não de cio através da avaliação histológica do endométrio e das concentrações plasmáticas de progesterona. Pesquisa Veterinária Brasileira 27(12):506-512. Curso de Pós-Graduação em Clínica e Reprodução Animal, Rua Vital Brazil Filho 64, Niterói, RJ 24230-340, Brazil. E-mail: joana.vet@gmail.com.br The study aimed to compare endometrial histology and plasmatic progesterone (P4) concentration of repeat breeds and healthy mares. The hypothesis was that there is a correlation between infertility and endometrial histology and P4 concentration in both groups. A total of 36 Campolina and Mangalarga Marchador mares in reproductive age (3-23 years) were used, 11 of them were healthy mares (Control group, 7 embryo recipient and 4 embryo donors), and 25 repeat breeders (10 embryo recipient and 15 embryo donors), classified as based on their reproductive history. Endometrial and blood samples were collected for respectively histological and plasma progesterone concentration evaluation. The endometrial samples obtained after biopsy were fixed in Bouin’s fluid, processed, included in paraffin, and stained with Hematoxylin-Eosin (HE) for histopathological examination. Plasmatic progesterone concentrations were evaluated by enzyme immunoessay (ELISA). There was no correlation between progesterone concentration and fertility. But there was a positive correlation between age and fertility, as older mares had major tendency of subfertility than younger ones. There was also a correlation between biopsy categories and fertility, as more histological alterations were found, higher were the chances for the mares to be subfertile. However not all mares classified as Category I and II maintained pregnancy until parturition. Other factors could influence pregnancy maintenance. In the same way, not all mares in Category III were infertile. The endometrial biopsy was shown to be an easy and cheap diagnostic technique with minimal discomfort to the animals and, together with other data, to be a very important component in the investigation of mare fertility.

• Mare subfertility endometrial biopsy histopathology progesterone

Abstract in Portuguese:

ABSTRACT.- Eigenheer-Moreira J.F., Fernandes F.T., Queiroz F.J.R, Pinho T.G.& Ferreira A.M.R. 2007. [Comparative study of repeat breeds and healthy mares through endometrial histology and plasmatic progesterone concentrations.] Estudo comparativo de éguas repetidoras ou não de cio através da avaliação histológica do endométrio e das concentrações plasmáticas de progesterona. Pesquisa Veterinária Brasileira 27(12):506-512. Curso de Pós-Graduação em Clínica e Reprodução Animal, Rua Vital Brazil Filho 64, Niterói, RJ 24230-340, Brazil. E-mail: joana.vet@gmail.com.br The study aimed to compare endometrial histology and plasmatic progesterone (P4) concentration of repeat breeds and healthy mares. The hypothesis was that there is a correlation between infertility and endometrial histology and P4 concentration in both groups. A total of 36 Campolina and Mangalarga Marchador mares in reproductive age (3-23 years) were used, 11 of them were healthy mares (Control group, 7 embryo recipient and 4 embryo donors), and 25 repeat breeders (10 embryo recipient and 15 embryo donors), classified as based on their reproductive history. Endometrial and blood samples were collected for respectively histological and plasma progesterone concentration evaluation. The endometrial samples obtained after biopsy were fixed in Bouin’s fluid, processed, included in paraffin, and stained with Hematoxylin-Eosin (HE) for histopathological examination. Plasmatic progesterone concentrations were evaluated by enzyme immunoessay (ELISA). There was no correlation between progesterone concentration and fertility. But there was a positive correlation between age and fertility, as older mares had major tendency of subfertility than younger ones. There was also a correlation between biopsy categories and fertility, as more histological alterations were found, higher were the chances for the mares to be subfertile. However not all mares classified as Category I and II maintained pregnancy until parturition. Other factors could influence pregnancy maintenance. In the same way, not all mares in Category III were infertile. The endometrial biopsy was shown to be an easy and cheap diagnostic technique with minimal discomfort to the animals and, together with other data, to be a very important component in the investigation of mare fertility.

Abstract in English:

ABSTRACT.- La Paz M.N., Fonseca V.U., Campos D.B., Artoni L.P., Sousa L.M.M.C. & Papa P.C. 2007. [In vitro progesterone production from bovine corpus luteum throughout gestation.] Produção de progesterona in vitro pelas células do corpo lúteo bovino ao longo da gestação. Pesquisa Veterinária Brasileira 27(9):370376. Setor de Anatomia, Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques Paiva, 87, SP 05508-270, Brazil. E-mail: ppapa@usp.br The aim was to test the hypothesis that cultivated bovine luteal cells from three different thirds of pregnancy behave the same way as in vivo luteal cells relative to P4 production. Corpus luteum samples from days 90 (n=3), 150 (n=3) and 210 (n=3) of pregnancy were obtained at a local slaughterhouse. Under aseptic conditions cells were mechanically dispersed and cultivated in a 96 wells-plate. After 24 hours of culture, cells were washed and the precursor pregnenolone was added. Experiments were conducted eight times for each studied time period (24, 48 and 96 h) and three times for each gestational age. Culture medium and cells were collected after 24, 48 and 96 hours of precursor addition and kept frozen at -20oC until processing. Progesterone was measured by RIA and protein content by Lowry’s method. Results were statistically analyzed and considered different when p <0.05. A higher P4 production was observed on day 90 of gestation (35.277±0.075), then this production was decreased at day 150 (28.820±0.231) and increased again at day 210 (32.777±0.099). After 24 hours of culture, luteal cells P4 production reached maximum values in the group of 90 days (2.912±0.047) when compared to 150 (2.669±0.137) and 210 days (2.741±0.088). At 48 and 96 hours of culture, bovine luteal cells from day 90 of gestation produced more P4 than cells from day 210 (2.934±0.029 and 2.976±0.121 respectively x 2.760±0.059 and 2.695±0.149, respectively; p<0.05), which in turn, produced more P4 than cells from day 150 (2.334±0.084 for 48 h and 2.205±0.136 for 96 h). Luteal cells from day 150 of gestation presented a decreasing P4 production throughout the 96 hours of culture. These differences could be explained by differential gene expression of enzymes and/or factors belonging to the esteroidogenic cascade in accordance to the gestational period. The established luteal cell culture model could be used for further functional studies once P4 secretion pattern in vitro resembled what occurs in vivo.

• Corpus luteum gestation progesterone cell culture

Abstract in Portuguese:

ABSTRACT.- La Paz M.N., Fonseca V.U., Campos D.B., Artoni L.P., Sousa L.M.M.C. & Papa P.C. 2007. [In vitro progesterone production from bovine corpus luteum throughout gestation.] Produção de progesterona in vitro pelas células do corpo lúteo bovino ao longo da gestação. Pesquisa Veterinária Brasileira 27(9):370376. Setor de Anatomia, Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques Paiva, 87, SP 05508-270, Brazil. E-mail: ppapa@usp.br The aim was to test the hypothesis that cultivated bovine luteal cells from three different thirds of pregnancy behave the same way as in vivo luteal cells relative to P4 production. Corpus luteum samples from days 90 (n=3), 150 (n=3) and 210 (n=3) of pregnancy were obtained at a local slaughterhouse. Under aseptic conditions cells were mechanically dispersed and cultivated in a 96 wells-plate. After 24 hours of culture, cells were washed and the precursor pregnenolone was added. Experiments were conducted eight times for each studied time period (24, 48 and 96 h) and three times for each gestational age. Culture medium and cells were collected after 24, 48 and 96 hours of precursor addition and kept frozen at -20oC until processing. Progesterone was measured by RIA and protein content by Lowry’s method. Results were statistically analyzed and considered different when p <0.05. A higher P4 production was observed on day 90 of gestation (35.277±0.075), then this production was decreased at day 150 (28.820±0.231) and increased again at day 210 (32.777±0.099). After 24 hours of culture, luteal cells P4 production reached maximum values in the group of 90 days (2.912±0.047) when compared to 150 (2.669±0.137) and 210 days (2.741±0.088). At 48 and 96 hours of culture, bovine luteal cells from day 90 of gestation produced more P4 than cells from day 210 (2.934±0.029 and 2.976±0.121 respectively x 2.760±0.059 and 2.695±0.149, respectively; p<0.05), which in turn, produced more P4 than cells from day 150 (2.334±0.084 for 48 h and 2.205±0.136 for 96 h). Luteal cells from day 150 of gestation presented a decreasing P4 production throughout the 96 hours of culture. These differences could be explained by differential gene expression of enzymes and/or factors belonging to the esteroidogenic cascade in accordance to the gestational period. The established luteal cell culture model could be used for further functional studies once P4 secretion pattern in vitro resembled what occurs in vivo.

Abstract in English:

Plasma concentrations of total estrogen and progesterone were determine d by radioimmunoassay in 49 cows that were brought to the Bovine Obstetrical and Gynecological Clinic, College of Veterinary Medicine of Hanover. Blood samples were taken at parturition and until 36 hours post partum at six hour intervals. At parturition, the average total estrogen concentration in the plasma of animals that underwent cesarian section, forced extration or fetotomy were 5.05 ± 2.88, 4.68 ± 2.44 and 2.34 ± 1.93 nmol/liter, respectively. Large individual variations we"re detected. The average total estrogen concentration detected in cows in the fetotomy treatment group was significantly different from the concentration in cows subjected to cesarian section or force d extraction at the time of parturition (P < 0.01 and P < 0.05, respectively) and 6 hours later (P < 0.001 for both). After delivery, all cows showed a sharp decline in the total estrogen levei in the plasma, with average values of than 1 nmol/1 of plasma being measured at 12 hours and thereafter. No significant differences in progesterone concentrations were detected in the plasma of cows at any time, regardless of the type of obstetrical intervention.

• Hormones estrogen progesterone radioimmunoassay cattle parturition obstetrical intervention

Abstract in Portuguese:

As concentrações de estrógeno total e progesterona foram determinadas pelo método RIE (radiomunoensaio) no plasma sanguíneo de 49 vacas da raça "Holstein Friesien", encaminhadas à Clínica Obstétrica e Ginecológica da Escola Superior de Medicina Veterinária de Hannover. As coletas de sangue foram praticadas no momento do parto e posteriormente, a cada seis horas, até completar 36 horas. As médias das concentrações de estrógeno total, no plasma de animais que sofreram cesariana, tração forçada ou fetotomia, no momento do parto, foram 5,05 ± 2,88, 4,68 ± 2,44 e 2,34 ± 1,93 nmol/1, respectivamente. Observaram-se grandes variações individuais nos valores obtidos. A média de concentração de estrógeno total detectada em animais que sofreram fetotomia, apresentou diferença estatisticamente significante em relação àquela encontrada nas vacas que foram submetidas a cesarias ou a partos tracionados tanto no momento do parto (P < 0,01 e P < 0,05, respectivamente), com 6 horas após (P < 0,001 para ambos). Após o parto houve um declínio brusco de estrógeno total e, em média, 12 horas depois registraram-se valores plasmáticos inferiores a 1 nmol/1. Independentemente das condutas obstétricas, não foi registrada diferença estatisticamente significante nas concentrações de progesterona encontradas durante e após o parto.

• Hormônios estrógeno progesterona radioimunoensaio vaca parto obstetrícia