Human placental villi are covered by a layer of trophoblast epithelia in direct contact with maternal blood, which exist in a constant steady-state of turnover and renewal ensuring both maternal and fetal health. The process of trophoblast turnover involves proliferation, differentiation and fusion of cytotrophoblast cells to form a terminally differentiated outer syncytiotrophoblast layer which functions as the active transport compartment between mother and fetus. Alterations in the balance between these three processes are thought to diminish both the structural and functional integrity of the syncytiotrophoblast, potentially leading to placental insufficiency associated with severe complications of pregnancy such as pre-eclampsia (PET), intrauterine growth restriction (IUGR) and sudden infant death syndrome (SIDS). Placentas from early (<32 weeks) and late-onset (>33 weeks) pregnancies complicated by PET, IUGR, SIDS and gestational age-matched controls were systematically uniform randomly sampled to assess the morphological basis of placental villous structure and trophoblast turnover (villi, cytotrophoblast, syncytiotrophoblast, apoptotic syncytial knots) using unbiased stereological techniques (volumes and numbers). Villous cytotrophoblast proliferation was assessed using double immunohistochemistry for Ki67 and cytokeratin 7 (CK-7). Severe early-onset IUGR placentas (n=5) were smaller displaying significant reductions in the total number of CT cells, within which the density of proliferating CT was further reduced by 50%. Syncytiotrophoblast volume and number was significantly reduced with an increase in apoptotic syncytial knots. Late-onset IUGR placentas (n=4) also displayed significant reductions in the total number of CT and proliferating CT, but were not associated with changes in the density of proliferating CT. SCT numbers were significantly reduced with an increase in apoptotic knots. Placentas from severe early-onset PET (n=11) were similar to preterm controls, except for a significant increase in apoptotic syncytial knots. However, late-onset PET (n=6) displayed a significant decrease in total CT number, the percentage of which undergoing proliferation was significantly increased for structural villi. There were increased numbers of apoptotic syncytial knots in peripheral villi.

Made available in DSpace on 2014-06-11T19:35:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-08Bitstream added on 2014-06-13T20:26:13Z : No. of bitstreams: 1 privadofilho_jr_dr_jabo.pdf: 801638 bytes, checksum: d98f692fdecb81ee726aeb25f6e86da4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram acompanhados 2.514 partos de fêmeas suínas de ordem de parto um e dois, com o objetivo de avaliar as taxas de leitões nascidos totais, vivos, natimortos e mumificados. Foram agrupadas as parições em dois períodos denominados, quente (1º e 4º trimestres) e ameno (2º e 3º trimestres). Dos 28.617 leitões nascidos, a ordem de parto um apresentou 4,7% de natimortos e 2,9% mumificados, e a ordem de parto dois teve uma ocorrência de 5% de natimortos e 2,5 de mumificados. O percentual de natimortos e mumificados foi maior no período quente, nas duas ordens de parição, a maior taxa de natimortalidade foi 6,2% e 7,4% nas duas ordens de parição respectivamente. As maiores médias de leitões nascidos totais também ocorreram no período quente (4º trimestre) 12,35 leitões/leitegada na ordem de parto um e 11,38 leitões/leitegada na ordem de parto dois / The objective of the paper was to follow 2.514 farrows in sows in one and two parity order to evaluate the total piglets born, piglets born alive, stillbirths and mummifies. The farrows were putted together in two periods named: hot season (1th and 4th quarters) and mild season (2th and 3th quarters). The 28.617 piglets born, the parity order one showed 4,7% of stillbirths and 2,9% of mummifies and the parity order two showed 5,0% of stillbirths and 2,5% of mummifies. The percentage of stillbirths and mummifies were higher in the hot season comparing with the mild season, in both parity orders. The highest stillbirth rate was 6,2% and 7,4% in the two parity orders, respectively. The highest average of total piglets born also occurred in the hot season (4th quarter) 12,35 piglets /litter in the parity order one and 11,38 piglets / litter on the parity order two

Orientador: Gilson Hélio Toniollo / Banca: Paulo Henrique Franceschine / Banca: Antonio Carlos Alessi / Banca: Karen Martins Leão / Banca: Fabiana Ferreira Souza / Resumo: Foram acompanhados 2.514 partos de fêmeas suínas de ordem de parto um e dois, com o objetivo de avaliar as taxas de leitões nascidos totais, vivos, natimortos e mumificados. Foram agrupadas as parições em dois períodos denominados, quente (1º e 4º trimestres) e ameno (2º e 3º trimestres). Dos 28.617 leitões nascidos, a ordem de parto um apresentou 4,7% de natimortos e 2,9% mumificados, e a ordem de parto dois teve uma ocorrência de 5% de natimortos e 2,5 de mumificados. O percentual de natimortos e mumificados foi maior no período quente, nas duas ordens de parição, a maior taxa de natimortalidade foi 6,2% e 7,4% nas duas ordens de parição respectivamente. As maiores médias de leitões nascidos totais também ocorreram no período quente (4º trimestre) 12,35 leitões/leitegada na ordem de parto um e 11,38 leitões/leitegada na ordem de parto dois / Abstract: The objective of the paper was to follow 2.514 farrows in sows in one and two parity order to evaluate the total piglets born, piglets born alive, stillbirths and mummifies. The farrows were putted together in two periods named: hot season (1th and 4th quarters) and mild season (2th and 3th quarters). The 28.617 piglets born, the parity order one showed 4,7% of stillbirths and 2,9% of mummifies and the parity order two showed 5,0% of stillbirths and 2,5% of mummifies. The percentage of stillbirths and mummifies were higher in the hot season comparing with the mild season, in both parity orders. The highest stillbirth rate was 6,2% and 7,4% in the two parity orders, respectively. The highest average of total piglets born also occurred in the hot season (4th quarter) 12,35 piglets /litter in the parity order one and 11,38 piglets / litter on the parity order two / Doutor

Thesis (MPH.) -- University of Limpopo, 2022 / Background: Stillbirth rates are a health problem and they cause distractions in the families. There are more than 5 million perinatal deaths occurring each year, ending preventable stillbirths and neonatal deaths continues to form a significant part of the international public health agenda beyond 2015. There are several risk factors which are associated with stillbirths and this could be classified as maternal, foetal and external risk factors. Therefore, the focus of the study was on the prevalence and determinants of stillbirths in Dilokong Hospital of the Limpopo Province. Methods: A retrospective descriptive study was conducted which followed a quantitative approach. This study used secondary data from patient clinical records from the maternity ward in Dilokong Hospital. Comparison between groups for continuous and categorical variables was performed using student t-test, and chisquare test, respectively. P-value less than 0.05 at 95% confidence level was regarded as significant. Findings: The prevalence of stillbirth amongst women who delivered at Dilokong hospital between period 2016 and 2019 was 13.5 % (CI: 0.12 – 15.2). The prevalence of stillbirth is stratified by year and it shows that highest prevalence was in 2018 at 42.5% followed by 2017, 2019 and 2016 at 23.2%, 19.7% and 14.6 respectively. The prevalence of stillbirth increased with increasing maternal age from 0.4% in the age group ≤14 years to 26.2% then decreased to 21.5% in the age group 30 – 34 years. The prevalence of macerated stillbirth between period 2016 and 2019 was 11.0%, for fresh stillbirth was 2.6 %. There was significant association of age, marital status of pregnant women, level of education, parity, gravidity, syphilis and HIV status. Older women at age 18 years and above were 1.4 times more likely to have stillbirth and 1.9 times more likely to have fresh stillbirth at p<0.05. Single women were 3.3 times more likely to have stillbirth and 3 times more likely to have macerated stillbirth as compared to married women. Fresh stillbirth was not significantly associated with marital status of pregnant women. Educational level was significantly associated with both stillbirth and macerated stillbirth as those women with no education or having primary educational level were 12.3 times more likely to have stillbirth and 14 times more likely to have macerated stillbirth as compared to women with tertiary educational level. vi Women who had pregnancies that have each resulted in the birth of an infant capable of survival (parity) for four or more times were 2.4 times more likely to have stillbirth and women who were in their fifth or more pregnancies (gravida) were 1.8 times more likely to have stillbirth and 3 times more likely to have fresh stillbirth. Lastly, women who had tested positive for syphilis were 4.1 times more likely to have stillbirth and 3.7 times more likely to have macerated stillbirth and women who were HIV positive were 3.1 times more likely to have stillbirth and 2.3 times more likely to have macerated stillbirth. CONCLUSION: The prevalence of stillbirth was very high in the current study and there is a need for studies on stillbirth and related factors in rural areas of Limpopo Province. This study showed that maternal age, low educational level, marital status of pregnant women, high parity, gravidity, syphilis and HIV status were statistically associated with stillbirth. The factors associated with stillbirth in the current study are preventable if quality focused antenatal care, intrapartum care is provided. Therefore, identification of pregnancy complications and facilitation of proper method of delivery is key to improve quality of care. Efforts to reduce unacceptably high stillbirth in the current study are needed. This study recommends that pregnant mothers need to be educated about the dangers in pregnancy and importance of antenatal visits.

Perdas devido à natimortalidade, mumificação fetal, abortamentos e morte embrionária são responsáveis por uma considerável queda no desempenho da indústria suinícola no Brasil e no mundo. Dentre os agentes mais freqüentemente descritos como causadores de falhas reprodutivas em suínos pode-se citar o Parvovírus suíno, Leptospira spp. O diagnóstico das causas infecciosas de mortalidade embrionária e fetal torna-se muitas vezes inviável pelo estado de autólise do material ou dificuldades inerentes às características de crescimento do vírus ou bactéria envolvido. O presente estudo teve por objetivo avaliar os resultados obtidos no período de oito anos de detecção de Parvovirus suíno e Leptospira spp. em falhas reprodutivas e discutir alguns aspectos relativos ao diagnóstico destas infecções. Foram avaliados 1901 fetos, sendo coletadas de cada animal, uma amostra de pool de órgãos e uma de conteúdo gástrico, perfazendo um total de 3642 análises. Observou-se uma freqüência de 27,6% dos fetos positivos para Parvovirus suíno, 19,8% positivos para Leptospira spp e 1,1% positivos para os dois agentes em associação. Dentre as 339 granjas avaliadas em oito Estados Brasileiros, 48,5% foram positivas para um ou ambos agentes pesquisados. Avaliou-se a freqüência de fetos positivos em casos de abortamento, natimortalidade e mumificação fetal e comparou-se a eficiência da pesquisa dos agentes em amostras de órgãos, conteúdo gástrico e em ambos. Os resultados obtidos indicam a grande importância destes agentes infecciosos nos quadros de falha reprodutiva em granjas de suínos no Brasil, apesar da ampla utilização de vacinas contra os mesmos. . / Losses due to stillbirths, mummification, embryonic death and abortions account for a considerable drop in performance of the pig industry in Brazil and the world. Among the agents most frequently described as causes of reproductive failure in pigs may be mentioned the swine parvovirus, Leptospira spp. The diagnosis of infectious causes of fetal and embryonic mortality it is often impossible for the state of autolysis of the material or the difficulties inherent growth characteristics of the virus or bacteria involved. Present study has the goal evaluate the results obtained in eight year period of Parvovirus and Leptospira spp. detection in reproductive failure and discuss some aspects related to diagnosis of these infections. A total of 1901 fetuses were examined, and from each animal a sample of different tissues and a sample of gastric contents were collected, representing 3642 analysis. A frequency of 27.6% of Parvovirus positive fetuses were observed, followed by 19.8% of Leptospira spp. positive fetuses, and 1.1% positive to both agents. Among 339 swine herds evaluated from eight Brazilian States, 48,5% were positive to one or both infectious agents. The frequency of positive fetuses in abortion, stillbirths and mummification, and the efficiency of virus and bacterial detection from organs and gastric contents were compared. The results obtained indicate the high importance of these infectious agents in reproductive failure in Brazilian swine herds, beside the large utilization of commercial vaccines against then.

Perdas devido à natimortalidade, mumificação fetal, abortamentos e morte embrionária são responsáveis por uma considerável queda no desempenho da indústria suinícola no Brasil e no mundo. Dentre os agentes mais freqüentemente descritos como causadores de falhas reprodutivas em suínos pode-se citar o Parvovírus suíno, Leptospira spp. O diagnóstico das causas infecciosas de mortalidade embrionária e fetal torna-se muitas vezes inviável pelo estado de autólise do material ou dificuldades inerentes às características de crescimento do vírus ou bactéria envolvido. O presente estudo teve por objetivo avaliar os resultados obtidos no período de oito anos de detecção de Parvovirus suíno e Leptospira spp. em falhas reprodutivas e discutir alguns aspectos relativos ao diagnóstico destas infecções. Foram avaliados 1901 fetos, sendo coletadas de cada animal, uma amostra de pool de órgãos e uma de conteúdo gástrico, perfazendo um total de 3642 análises. Observou-se uma freqüência de 27,6% dos fetos positivos para Parvovirus suíno, 19,8% positivos para Leptospira spp e 1,1% positivos para os dois agentes em associação. Dentre as 339 granjas avaliadas em oito Estados Brasileiros, 48,5% foram positivas para um ou ambos agentes pesquisados. Avaliou-se a freqüência de fetos positivos em casos de abortamento, natimortalidade e mumificação fetal e comparou-se a eficiência da pesquisa dos agentes em amostras de órgãos, conteúdo gástrico e em ambos. Os resultados obtidos indicam a grande importância destes agentes infecciosos nos quadros de falha reprodutiva em granjas de suínos no Brasil, apesar da ampla utilização de vacinas contra os mesmos. . / Losses due to stillbirths, mummification, embryonic death and abortions account for a considerable drop in performance of the pig industry in Brazil and the world. Among the agents most frequently described as causes of reproductive failure in pigs may be mentioned the swine parvovirus, Leptospira spp. The diagnosis of infectious causes of fetal and embryonic mortality it is often impossible for the state of autolysis of the material or the difficulties inherent growth characteristics of the virus or bacteria involved. Present study has the goal evaluate the results obtained in eight year period of Parvovirus and Leptospira spp. detection in reproductive failure and discuss some aspects related to diagnosis of these infections. A total of 1901 fetuses were examined, and from each animal a sample of different tissues and a sample of gastric contents were collected, representing 3642 analysis. A frequency of 27.6% of Parvovirus positive fetuses were observed, followed by 19.8% of Leptospira spp. positive fetuses, and 1.1% positive to both agents. Among 339 swine herds evaluated from eight Brazilian States, 48,5% were positive to one or both infectious agents. The frequency of positive fetuses in abortion, stillbirths and mummification, and the efficiency of virus and bacterial detection from organs and gastric contents were compared. The results obtained indicate the high importance of these infectious agents in reproductive failure in Brazilian swine herds, beside the large utilization of commercial vaccines against then.

Thesis (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2020 / Stillbirth is a trait of high economic importance in dairy cattle and is increasingly being included in dairy cattle breeding objectives worldwide. In South Africa, however, there is limited information on stillbirth that can be used to improve this trait genetically. Currently, there are no estimated breeding values (EBVs) for any measures of calving performance produced under the national genetic evaluation programme. The current study was, therefore, conducted to assess the incidence of stillbirth and estimate the genetic and environmental influences on maternal effects for stillbirth in South African Holstein cattle, to enable estimation of breeding values for the trait. Data used in the study comprised 13 143 calving records of 7 723 Holstein cows, from 41 herds, participating in the National Dairy Animal Recording and Improvement Scheme during the period 2014 to 2018. Incidence of stillbirth was determined using the PROC FREQ procedure and environmental effects were tested by the General Linear Models (GLM) procedure of Statistical Analysis System (SAS 9.4, 2016). Maternal heritability of stillbirth was estimated by the Restricted Maximum Likelihood (REML) procedure, using the ASReml software (Gilmour et al., 2018). The analyses were carried out using a threshold animal model and a repeatability animal model, where the latter considered stillbirth in different parities as repeated measures of the same trait. Environmental effects significantly influencing stillbirth (p<0.05) were herd-year season of calving, dam parity and calf sex, and these were included in the model for variance component estimation. Estimates of maternal heritability effects from the threshold animal model were 0.12±0.04, 0.15±0.08 and 0.14±0.06 for parities 1 to 3, respectively. The repeatability animal model gave a heritability estimate of 0.09±0.03 and a repeatability of 0.18±0.03. The moderate estimates of maternal heritability indicate scope for reducing incidence of stillbirth by selectively breeding cows that are less genetically predisposed to calving dead calves. Stillbirth in different parities should not be considered as the same trait, as indicated by the low repeatability estimate. Results of the current study estimate genetic parameters that are required to compute accurate estimated breeding values (EBVs) for stillbirth, which will enable South African Holstein farmers to select for reduced stillbirths, thus improving calving performance / National Research Foundation (NRF), University of Limpopo (UL) and Department of Agriculture Forestry and Fisheries (DAFF)