Abstract Radiotherapy causes destruction of tumor cells, but also threatens the integrity and survival of surrounding normal cells. Then, woman submitted to irradiation for cancer treatment may present permanent ovary damage, resulting in impaired fertility. The objective of this study was to investigate the effects of therapeutic doses of ionizing radiation (IR), used for ovarian cancer treatment in humans, on bovine cumulus-oocyte complexes (COCs) as experimental model. Bovine ovaries were exposed to 0.9 Gy, 1.8 Gy, 3.6 Gy or 18.6 Gy IR, and then COCs were collected and used to evaluate: (a) oocyte nuclear maturation; (b) presence of phosphorylated H2A.X (γH2AX), as an indicator of DNA double-strand breaks (DSBs); and (c) expression of genes involved in DNA repair (TP53BP1, RAD52, ATM, XRCC6 and XRCC5) and apoptosis (BAX). The radiation doses tested in this study had no detrimental effects on nuclear maturation and did not increase γH2AX in the oocytes. However, IR treatment altered the mRNA abundance of RAD52 (RAD52 homolog, DNA repair protein) and BAX (BCL2-associated X protein). We conclude that although IR doses had no apparent effect on oocyte nuclear maturation and DNA damage, molecular pathways involved in DNA repair and apoptosis were affected by IR exposure in cumulus cells.

Abstract The transforming growth factors beta (TGFβ) are local factors produced by ovarian cells which, after binding to their receptors, regulate follicular deviation and ovulation. However, their regulation and function during corpus luteum (CL) regression has been poorly investigated. The present study evaluated the mRNA regulation of some TGFβ family ligands and their receptors in the bovine CL during induced luteolysis in vivo. On day 10 of the estrous cycle, cows received an injection of prostaglandin F2α (PGF) and luteal samples were obtained from separate groups of cows (n= 4-5 cows per time-point) at 0, 2, 12, 24 or 48 h after treatment. Since TGF beta family comprises more than 30 ligands, we focused in some candidates genes such as activin receptors (ACVR-1A, -1B, -2A, -2B) AMH, AMHR2, BMPs (BMP-1, -2, -3, -4, -6 and -7), BMP receptors (BMPR-1A, -1B and -2), inhibin subunits (INH-A, -BA, -BB) and betaglycan (TGFBR3). The mRNA levels of BMP4, BMP6 and INHBA were higher at 2 h after PGF administration (P<0.05) in comparison to 0 h. The relative mRNA abundance of BMP1, BMP2, BMP3, BMP4, BMP6, ACVR1B, INHBA and INHBB was upregulated up to 12 h post PGF (P<0.05). On the other hand, TGFBR3 mRNA that codes for a reservoir of ligands that bind to TGF-beta receptors, was lower at 48 h. In conclusion, findings from this study demonstrated that genes encoding several TGFβ family members are expressed in a time-specific manner after PGF administration.

O objetivo do presente estudo foi avaliar a eficiência de dispositivos intravaginais (DIVs) contendo progestágeno na prevenção do parto e determinar o efeito do atraso do parto sobre a proporção de leitões vivos/nascidos totais. DIVs contendo 0,5, 1,0 ou 1,5g de progesterona (P4) não foram eficientes na prevenção do parto em nenhuma das doses. No experimento 2, setenta e cinco porcas aos 112 dias de gestação foram equilibradamente distribuídas (n=15 por grupo) nos seguintes tratamentos: prostaglandina (PGF2α; 250µg cloprostenol sódico; grupo controle) ou PGF2α e simultânea inserção de DIV contendo acetato de medroxiprogesterona (MAP) por 48h. Fêmeas do grupo controle iniciaram o parto 27,7±1,6h após injeção de PGF2α. O tempo médio entre a administração de PGF2α e início do parto foi 72,1±8,8h, 72,7±3,8h, 82,7±7,1h e 81,8±3,5h para os grupos MAP 100, 200, 400 e 800mg, respectivamente, diferindo do grupo controle (P<0,05). Para avaliar o efeito da inibição do parto sobre a proporção de leitões nascidos vivos, porcas entre 109 e 112 dias de gestação receberam DIVs contendo 800mg MAP (quintas-feiras) por 72h para prevenir o parto aos finais de semana e foram tratadas com PGF2α no momento da retirada dos DIV (aos domingos). A razão leitões vivos/nascidos totais foi 89,0±1,6, 90,1±1,2 e 89,0±1,5% nos grupos controle (Normal; n=57 porcas), induzido com PGF2α (Induzido; n=57 porcas) e PGF2α+DIV (MPA800; n=56 porcas), respectivamente (P>0,05). Esses resultados confirmam que DIVs contendo MAP podem efetivamente inibir o início do parto em porcas sem afetar a proporção de leitões nascidos vivos e, portanto, representam uma alternativa para evitar partos aos finais de semana.

The objective of this study was to evaluate the efficiency of progestagen intravaginal devices (IVDs) in preventing parturition in sows by determining the effect of delaying parturition on the alive/total born piglets ratio. Evaluations of IVDs containing 0.5, 1.0 or 1.5g progesterone (P4) showed they were not effective in delaying parturition at any dosage tested. In a second experiment, seventy-five sows at day 112 of pregnancy were equally distributed (n=15 per group) in the following treatments: prostaglandin (PGF2α; 250µg sodium cloprostenol; control group) or PGF2α and simultaneous insertion of an IVD containing medroxyprogesterone acetate (MPA) for 48h. Control sows initiated labor 27.7±1.6h after PGF2α injection. The mean time (±SEM) between PGF2α administration and parturition was 72.1±8.8h, 72.7±3.8h, 82.7±7.1h and 81.8±3.5h for MPA 100, 200, 400 and 800mg, respectively, differing from control group (P<0.05). To evaluate the effect of delaying parturition on the alive/total born piglets ratio at birth, sows between days 109 and 112 of gestation received IVDs containing 800mg MPA (on Thursdays) for 72h to prevent parturition in weekends and then were treated with PGF2α at the time of device withdrawal (on Sundays). The alive/total born piglets ratio was 89.0±1.6, 90.1±1.2 and 89.0±1.5% for control (Normal group; n=57 sows), PGF2α-induced (Induced group; n=57 sows), and IVD+PGF2α-induced (MPA800 group, n=56 sows) groups, respectively (P>0.05). These findings confirm that IVDs impregnated with MPA can effectively prevent parturition in sows without affecting the alive/total born piglets ratio and therefore represent an alternative to avoid weekend farrowing in swine herds.

O objetivo deste trabalho foi avaliar a utilização de dispositivos intravaginais (DIV) para o controle da reprodução em suínos. Porcas aos 112 dias de gestação receberam injeção de PGF2α (controle, n = 15) ou PGF2α com inserção de DIV contendo acetato de medroxiprogesterona (grupo DIV, n = 14) por 48 horas. As fêmeas iniciaram o parto 27,7±1,6 e 82,3±3,8 horas após aplicação de PGF2α nos grupos controle e tratado, respectivamente. Quanto ao controle do estro, dez porcas receberam DIV por 12 dias, iniciando imediatamente após o desmame, e o estro foi confirmado aos 17,25±0,17 dias após o desmame, em comparação a 4±0,25 dias no grupo controle. Dispositivos intravaginais com progestágeno podem ser utilizados no controle da reprodução em suínos.

The objective of this work was to evaluate the use of intravaginal devices (IVD) for the control of reproductive events in swine. Sows at 112 days of pregnancy received an injection of PGF2α (control, n = 15) or PGF2α plus an IVD containing medroxyprogesterone acetate (IVD group, n = 14) for 48 hours. Sows initiated labor 27.7±1.6 and 82.3±3.8 h after PGF2α aplicaction, in control and treated groups, respectively. Regarding control of estrus cycle, ten sows received IVD for 12 days starting immediately after weaning, and estrus was confirmed 17.25±0.17 days after weaning, in comparison to 4.00±0.25 days for the control group. Intravaginal devices with progestagen can be applied for the control of reproduction in swine.

O objetivo deste estudo foi avaliar as causas de infertilidade em vacas de corte repetidoras de serviço, relacionando sinais clínicos com características laboratoriais post-mortem. A identificação dos fatores que afetam o desempenho reprodutivo pode fornecer uma fundamentação científica para auxiliar na decisão quanto ao destino de vacas repetidoras de serviço; tratamento ou descarte. Este estudo tem abordagem diferencial dos trabalhos que contemplam somente a ocorrência de alterações post-mortem do trato genital. A correlação das alterações post-mortem com o histórico clínico dos animais pode auxiliar na determinação da causa de repetição de serviço de animais sem alteração clínica. Foram utilizadas 130 vacas e novilhas cruzas que não conceberam depois de, no mínimo, três serviços. Todos os animais foram identificados e submetidos à exame clínico e coleta de sangue para cariotipagem. Foram incluídos no estudo apenas animais com histórico de falha reprodutiva. Os animais foram encaminhados para um abatedouro e foram realizados exames post-mortem como inspeção macroscópica do trato genital, cultura bacteriológica e estudo histopatológico do útero. Alterações uterinas foram predominantes seguidas de alterações de oviduto e ovário. Foi observada uma maior freqüência de alterações histopatológicas de útero que alterações clínicas. Os animais utilizados no estudo apresentaram alta freqüência de patologia uterina (95%), tanto inflamatórias (42,9%) quanto degenerativas (59,7%). Patologias diagnosticadas somente por exames post-mortem e laboratoriais como oclusão tubária (29,8%) e trissomia do par sexual também foram observadas (1/10 vacas). Portanto, este estudo evidencia a importância do exame laboratorial no diagnóstico das causas de infertilidade de vacas com histórico de repetição de serviço.

The objective of this study was to investigate the causes of the repeat breeder syndrome comparing clinical signs and postmortem findings in beef cows. The identification of factors affecting the reproductive tract can support decisions as to whether treatment of repeat breeder cows is justifiable than culling. Since all animals were submitted to clinical examination before being slaughtered, this study has a differential approach when compared with others, where genital tracts from abattoir were examined. In this study, 130 crossbred cows and heifers that have failed to conceive after three or more services were identified, submitted to a clinical examination and blood collection for karyotyping and sent to an abattoir. postmortem examinations included macroscopic evaluation of the genital tracts, bacteriology and histopathology of the uterus. Uterine alterations were predominant followed by oviduct and ovarian pathologies. Histopathological examination was more sensitive as a diagnostic tool than clinical examination. Repeat breeder cows had a predominance of uterine abnormalities (95%), such as inflammatory (42.9%) and degenerative (59.7%) conditions. Oviduct abnormalities were found in 29.8 % of animals. Furthermore, 1 out 10 karyotyped cows showed aneuploidy. Thus, this study stressed the importance of laboratory exams in the diagnosis of the causes of infertility of repeat breeder cows.

A gonadotrofina coriônica equina (eCG) foi purificada e caracterizada com respeito ao grau de pureza e atividade biológica. A pureza de quatro preparações foi determinada por eletroforese e a atividade biológica pelo incremento do peso ovariano de ratas imaturas (40 - 50g) e pela indução de ovulação em ovelhas e leitoas. A análise eletroforética revelou a presença de três bandas polipeptídicas. A atividade biológica media foi de 313 UI/mg de proteína. Sessenta e cinco (65) ovelhas, fora da estação reprodutiva, foram divididas ao acaso em dois grupos os quais receberam implantes vaginais de esponjas impregnadas com acetato de medroxiprogesterona por um período de l l a 14 dias. No grupo I (55 ovelhas), foram injetadas (IM) 500UI do eCG purificado no momento da retirada das esponjas, enquanto que no grupo II (10 ovelhas) foram injetadas 500UI de eCG comercial. Uma semana após a aplicação do eCG as ovelhas foram submetidas a um exame laparoscópico para avaliar o número de ovulações. Obteve-se uma média de 2,1 ± 0,3 e 1,8 ± 0,3 ovulações (P>0,05) para as ovelhas dos grupos I e II, respectivamente. De 120 leitoas pré-púberes, com peso médio de 87,2 kg, 90 (grupo I) foram injetadas com 500UI do eCG purificado e, às 72 horas, 500UI de hCG (gonadotrofina coriônica humana), e 30 leitoas (grupo II) não receberam injeção hormonal. Observou-se a presença de 25,9 ± 22,2 e 0,0 corpora lutea (P<0,001), nos grupos I e II, respectivamente. Estes resultados demonstraram que o PMSG purificado apresenta pureza e atividade biológica similares ao produto comercial utilizado como controle e que é eficiente para induzir atividade ovariana em ovinos e suínos.

Equine chorionic gonadotrophin (eCG) was purified and characterized with respect to its purity and bionological activity. The purity of four preparations was determined by electrophoresis, and the biological activity by increasing of the ovarian weight ot immature female rats (40-50g) and induction ot ovulation of ewes and gilts. Electrophoretic analysis revealed three polipeptidic bands. The mean biological activity was 313UI/mg of protein. Sixty-five ewes, not in reproductive season, were divided randomly in two groups that received vaginal pessaries impregnated with medroxiprogesterone acetato for 11 to 14 days. In treatment I, ewes (n = 55) were injected (IM) with 500UI of puritied eCG at the moment of pessaries withdraw, while in treatment II, the ewes (n = 10) received 500UI of comercial eCG. The results observed were 2.1 ± 0.3 and 1.8 ± 0.3 ovulations (P > 0.05) for treatments I and II, respectively. One hundred-twenty gilts, with mean weight of 87.2kg, were divided m two treatments. The animals in treatment I (90 gilts) received 500UI of puntied eCG and, 72 hours later, 500UI of hCG (human chorionic gonadotrophin). In treatment II hormones were not injected. The results observed were 25.9 ± 22.2 and 0.0 corpora lutea (P < 0.001) for treatments I and II, respectively. These results demonstrated that the eCG purified has purity and biological activity similar to the comercial product used as control, and that it is efficient in inducing ovarian activity in ewes and gilts.