Histopathological characterization of the reproductive organs of heifers experimentally infected with Campylobacter fetus venerealis / Caracterización histopatológica de los órganos reproductivos de vaquillonas experimentalmente infectadas con Campylobacter fetus venerealis / Caracterização histopatológica em órgãos reprodutores de novilhas infetadas no modo experimental com Campylobacter fetus venerealis

Abstract Background: Bovine campylobacteriosis is a venereal disease due to infection with Campylobacter fetus venerealis. It causes mainly reproductive failures that lead to considerable economic losses. Objective: To perform a histopathological description of the mucosa from reproductive organs of heifers experimentally infected with Campylobacter fetus venerealis. Methods: Twelve 15-18-months-old Aberdeen Angus heifers were treated for estrous synchronization and exposed to natural breeding. They were then randomly divided into two groups: group A (n=9) was inoculated with C. fetus venerealis; group B (n=3, control) was inoculated with a placebo. Ultrasonography was performed at days 29, 38, and 42 post-breeding, and plasmatic progesterone levels were quantified using ELISA to confirm pregnancies. Animals in group A with plasma progesterone levels below 1 ng/mL and/or diagnosed as non-pregnant were further divided into three subgroups: A1 (n=4), euthanized at day 30 post-breeding; A2 (n=3), euthanized at day 40 post-breeding and A3 (n=2), euthanized at day 55 post-breeding. Heifers from group B, all diagnosed as pregnant, were euthanized each at day 30, 40, and 55 days post-breeding as well. Histological sections from every group were taken from oviducts, uterus, and vagina. Results: Lymphocytic inflammation was the most common lesion in all infected heifers. Trophoblast cells were found in the non-pregnant heifers euthanized at days 40, and 55 post-breeding. The inflammatory process with the presence of lymphoid cells probably altered the balance in the activity of maternal lymphoid cells, as well as gene expression of the trophoblast, finally affecting the embryo survival. Conclusion: This work contributes to the understanding of the histopathological process involved in post-mating infection of Campylobacter fetus bovine.

Resumen Antecedentes: La campilobacteriosis bovina es una enfermedad venérea causada por el Campylobacter fetus venerealis, que produce principalmente fallas reproductivas ocasionando grandes pérdidas económicas Objetivo: Describir las características histopatológicas de la mucosa de órganos reproductores de vaquillonas infectadas experimentalmente con Campylobacter fetus venerealis. Métodos: Doce vaquillonas Aberdeen Angus (15 a 18 meses de edad) con celo sincronizado, recibieron servicio natural, e inmediatamente se dividieron aleatoriamente en dos grupos: A (n=9), inoculadas con Campylobacter fetus venerealis; B (n=3; control), inoculadas con placebo. El diagnóstico de preñez se realizó por ultrasonografía a los 29, 38 y 42 días post-servicio; los niveles plasmáticos de progesterona fueron determinados por ELISA. Las vaquillonas del grupo A con niveles de progesterona plasmáticos menores a 1 ng/mL y/o diagnosticadas no preñadas, fueron consideradas para eutanasia y divididas en tres subgrupos: A1-eutanasia día 30 (n=4); A2-día 40 (n=3); y A3-día 55 (n=2) post-servicio. Las vaquillonas del grupo B, diagnosticadas preñadas, fueron eutanasiadas a los 30, 40 y 55 días. Se tomaron muestras de oviductos, útero y vagina. Resultados: Se observó inflamación linfocitaria en la totalidad de muestras del grupo A. Células trofoblásticas fueron encontradas en muestras correspondientes a los grupos A2 y A3. Probablemente, el proceso inflamatorio alteró el equilibrio de las células linfoides maternas y la expresión génica del trofoblasto, afectando la supervivencia embrionaria. Conclusión: Este trabajo contribuye a la comprensión del proceso histopatológico involucrado en la infección poscoital por Campylobacter fetus bovino.

Resumo Antecedentes: A campilobacteriose bovina é uma doença venérea originada pelo Campylobacter fetus venerealis, quem produz principalmente falha reprodutiva e porém grandes perdas económicas. Objetivo: Descrever as características histopatológicas da mucosa dos órgãos reprodutores de novilhas infetadas no modo experimental com Campylobacter fetus venerealis. Métodos: Doze novilhas Aberdeen Angus de 15 até 18 meses com cio sincronizado, receberam serviço natural. Logo após, foram aleatóreamente separados em grupos: A (n=9) inoculados com Campylobacter fetus venerealis e grupo B (n=3; controle) inoculadas com um placebo. O diagnóstico da gestação foi realizado por ultrasom nos dias 29, 38 y 42 pós-serviço. Os níveis plasmáticos da progesterona foram determinados por ELISA. As novilhas do grupo A, com níveis plasmáticos de progesterona menores a 1 ng/mL e/ou diagnosticadas não grávidas, foram consideradas para eutanásia e foram divididas em três subgrupos: A1-eutanásia aos 30 dias pós- serviço (n=4); A2-dia 40 (n=3); A3-dia 55 (n=2). Foram realizada eutanásia ás novilhas do grupo B diagnosticadas prenhadas, aos 30, 40 e 55 dias e a amostragem de ovidutos, útero e vagina. Resultados: A presença de inflamação linfocitária foi observada na totalidade das amostras do grupo A. Foram achadas células trofoblásticas nas amostras correspondente aos grupos A2 e A3. Provavelmente, pelo processo inflamatório tenha sido alterado o equilíbrio das células linfoides maternas, assim também como a expressão gênica do trofoblasto, afetando a supervivência embrionária. Conclusão: Este trabalho contribue á compreensão do processo histopatologico na infecção com Campylobacter fetus bovino pós-acasalamento.

Evaluation of potential embryo toxicity of albendazole sulphoxide in CF1 mice

Benzimidazole compounds are used in both humans and animals for controlling helminth parasites. Albendazole has teratogenic effects attributed to its active metabolite albendazole sulphoxide. The aim of this work was to evaluate the effect of the latter compound when administered to pregnant CF1 mice during the preimplantation period. Females were superovulated by intraperitoneal injection of 10 IU of eCG and 10 IU of hCG (48h later) and were paired with males of proven fertility. Albendazole sulphoxide (200 mg/kg) was orally administered by gavages at day 1, 2 or 3 of pregnancy; the control group received only the vehicle (carboxymethylcellulose). Females were killed by cervical dislocation at day 4 of pregnancy and embryos were flushed from uteri with Ham F10 media supplemented with bovine serum albumin (0.4%). Number of collected embryos per female, percentage of morphologically normal embryos, differentiation rate and number of cells per embryos were recorded. The variables were analyzed on a per litter basis by Kruskal-Wallis test. There was no effect of albendazole sulphoxide on parameters evaluated (P>0.05). We conclude that the preimplantation mouse embryo development was not significantly affected by albendazole sulphoxide.

Description of the characteristics of oocytes and zygotes of coypu, myocastor coypus

El objetivo del presente trabajo fue caracterizar morfológicamente los ovocitos y los cigotos de Myocastor coypus. Se utilizaron 17 ovocitos y 24 cigotos obtenidos por lavaje de los oviductos de hembras, a las que se practicó seguimiento colpocitológico diario y apareamiento dirigido. En el análisis de los ovocitos y los cigotos se consideraron aspectos morfológicos y de la polaridad celular y envolturas. Los ovocitos presentaron forma esférica con un diámetro celular de 85,7 ñ 3,1 µm. El espacio perivitelino ocupado, fue del 98 por ciento, con un espesor de la zona pelúcida de 15,9 ñ 1,9 µm. Se determinó la existencia de polaridad ovular. Los cigotos presentaron un diámetro externo a la zona pelúcida de 125 ñ 8,6 µm y un diámetro embrionario de 80,6 ñ 8,1 µm. En el 91,7 por ciento de los casos, se trató del estadio de cigotos de 2 pronúcleos. En todos los cigotos se observó una distribución homogénea de las granulaciones citoplasmática. Los cigotos presentaron a la zona pelúcida como única envoltura completa, obteniéndose pocos especímenes con células granulosas asociadas

Growth factors and embryo development

In this review are cited and discussed the possible roles of growth factors on preimplantation embryo development of different species. In first term, is considered the mRNA detection in early stages of development. The distribution pattern was not uniform for the different peptides evaluated. For some of them, the mRNAs are detected at the oocyte stage and the level declines to the blastocyst stage, which suggests a maternal origin for them. For others, the level increased from 2-4 cells to blastocyst stage. On the other hand, transcripts of growth factor receptors have been detected in preimplantation embryos. This suggests that growth factors of maternal or embryo origin interact with specific receptors on preimplantation embryo surface and regulate the early development. On the other hand, culture media supplemented with different growth factors have been used to study the possible effects on in vitro development. Some investigators have found no effect. Others, however, have demonstrated changes in protein synthesis, cell number, differentiation and hatching processes. Embryo development modulation by growth factors probably involves a balance between stimulatory and inhibitory effects, although works are needed to determine the precise roles played by these polypeptides during early stages of mammalian development.

Effect of embryo density and growth factors on in vitro preimplantation development of mouse embryos

Embryo development depends on maternal and embryonic factors that may regulate genetic programs in early development. Effects of growth factors on proliferation, differentiation and morphogenesis along embryogenesis have been documented. However, studies have not established the role of growth factors in the preimplantational period. The purpose of this study was to investigate the possible effects of growth factors and embryo density on mouse preimplantation development in vitro. Two-and eight-cell CF-1 embryos were cultured individually or in groups of ten in HTF medium, alone or with EGF, TGF-beta1 and IGF-I. Cleavage rate varied greatly with growth factors and increased significantly when eight-cell embryos were cultured in groups. On the other hand, when two-cell embryos were cultured in group, the cleavage rate was slower than that obtained when embryos were individually cultured. The differentiation rate increased significantly in two-cell embryos cultured in groups (p<0.05). EGF, TGF-beta1 and IGF-I increased differentiation rates significantly in two-cell embryos individually cultured for 68 hours. The combination of EGF and TGF-beta1 increased the differentiation rates significantly. The other combinations were not effective in modifying this parameter. Hatching rates increased in embryos cultured in groups (p<0.05). TGF-beta1 decreased this parameter significantly in two-or eight-cell embryos cultured in groups (p<0.05). The data described in this report suggest that preimplantational mouse embryos produce some factor or factors that enhance its development, specially the differentiation and hatching rates. However, a functional role for polypeptide growth factors during preimplantational development has to be determined.