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R F Mumm - One of the best experts on this subject based on the ideXlab platform.
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effect of calcium source dietary calcium concentration and Gestation Phase on various bone characteristics in gestating gilts
Journal of Animal Science, 1993Co-Authors: G L Walker, D M Danielson, E R Peo, R F MummAbstract:Sixty gravid crossbred gilts were allotted to a 2 x 3 x 2 factorial arrangement of treatments: two Ca sources (sun-cured alfalfa meal and CaC03), three dietary concentrations of Ca (50, 75, and 100% of NRC requirements), and two Phases of Gestation (55 and 105 d). The objectives were to determine the effect of Ca source, dietary Ca concen- tration, and Gestation Phase on bone characteristics (bone breaking strength, bone ash percentage, bone density, and bone ash density in the rib, thoracic, and coccygeal bones), to correlate bone responses to determine relative bone activity, and to determine reliability of the coccygeal bones as indicators of Ca status in the body. At 55 d, rib strength and coccygeal ash content were lower (P < .01) than at 105 d of Gestation. A Gestation Phase x Ca concentration (P < .0 5 ) interaction occurred. As Ca concentration in- creased, thoracic strength and rib ash responded quadratically during each Gestation Phase, for which at 55 d a minima and at 105 d a maxima was produced at 75% of NRC. A Ca source x Ca concentra- tion (P < .05) interaction occurred. Gilts fed alfalfa had the lowest rib bone and ash density when fed 75% of NRC for Ca, whereas gilts fed CaC03 were highest at this level of Ca compared with the other concentra- tions. Generally, all bones were positively correlated with respect to their response to dietary Ca concentra- tion. Few negative correlations were observed. At this level of physiological maturity, there was no effect of Ca source and little effect of Gestation Phase on the bone variables measured at the dietary Ca concentra- tions used in this experiment. The rib and thoracic bones seem to be the most responsive to dietary Ca concentration.
Gomes, Dayane Olímpia - One of the best experts on this subject based on the ideXlab platform.
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Production of IL-6 and IL-1β in ex vivo bovine endometrial cultures inoculated with Leptospira interrogans serovar Hardjoprajitno
'EDUFU - Editora da Universidade Federal de Uberlandia', 2020Co-Authors: Gomes, Dayane OlímpiaAbstract:Leptospirosis is a zoonosis caused by a bacteria belonging to genus Leptospira spp. There are reports of this bacteria isolation in the female reproductive tract with are related to abortion and subfertility in bovine herds. It is known that Leptospira presence in reproductive organs of bovines promotes tissue damages especially by vasculitis. Moreover, acute leptospirosis produces high levels of cytokines during the onset of infection. However, few studies were performed about the pathogenesis of this microorganism in the endometrium of cows. The objective of this study was to evaluate the inflammatory cytokines profile after Leptospira interrogans serovars Hardjoprajitno and LPS of Escherichia coli challenges produced by uterine tissue ex vivo of non-pregnant and pregnant cows serologically reactive or not to Microscopic Agglutination Test (MAT). A total of 43 uterus with respective blood samples were collected from crossbred cows, from those 19 were non-pregnant and 24 pregnant, without any clinical disease evidence. To determine the pregnancy Phase, the measurement of fetuses were performed. To analyze previous infection occurrence antibodies against Leptospira were evaluated by MAT. After endometrium exposure, fragments of endometrium tissue (explants) were collected using a punch of 8 mm in intercaruncular region. The processing of endometrial explants were done in a 24-well cell culture plates. The solutions added on explants were: a) Control medium (2 mL of RPMI solution); b) RPMI medium (1μg/mL of LPS from Escherichia coli); c) EMJH medium with inoculum of Leptospira interrogans serovars Hardjoprajitno (108 leptospires/mL). The plates were incubated at 37°C with 5% of CO2 for 24 hours. After this period, uterine explants were weighed and collected and subsequently tested for interleukins (IL-1β and IL-6) production profile by ELISA kits. Considering the challenge with 1μg/mL of LPS, both pregnant and non-pregnant cows build a response due to challenge with a significant increase in IL-1β and IL-6 production compared to control group. Considering the challenge with Leptospira, an increase of IL-6 concentration was verified in the explants of both pregnant and non-pregnant cows related to control. However, only the explants from non-pregnant cows showed an increase of IL-6 production related to control. In the individual evaluation of pregnancy Phases, during the initial Phase (first trimester) only occurred significant IL-6 production, differing from IL-1β which significant production increase occurred during late Gestation Phase in the challenge with 1μg/mL of LPS from E.coli. There was no difference in cytokines production according to pregnancy Phase after challenge with Leptospira. In conclusion, a higher stimulation of cytokines production was verified in endometrial tissues of reagent cows after LPS and Leptospira challenges; lower stimulation of IL-6 production in pregnant cows after Leptospira challenge; a higher stimulation during initial and late pregnancy Phases after LPS from E.coli challenge, and no significant difference between pregnancy Phases after Leptospira challenge.FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisTese (Doutorado)Leptospirose é uma zoonose causada por bactérias do gênero Leptospira spp. Existem relatos de isolamento desta bactéria no trato genital de fêmeas, relacionado à abortamento e infertilidade no rebanho bovino. Já se sabe que a Leptospira presente nos órgãos reprodutivos de bovinos causa danos teciduais principalmente pela vasculite. Além disso, a leptospirose aguda produz níveis altos de citocinas durante a fase inicial de infecção. Entretanto, faltam estudos sobre a patogênese desse microrganismo no endométrio de vacas. Objetivou-se avaliar o perfil das citocinas inflamatórias após o desafio com Leptospira interrogans sorovar Hardjoprajitno e ao LPS de Escherichia coli produzidas pelo tecido uterino ex vivo coletados de vacas não gestantes e gestantes reativas sorologicamente ou não ao Teste de soroaglutinação microscópica (MAT). Foram utilizados 43 úteros com respectivas amostras de sangue coletadas de vacas mestiças, sendo 19 delas não gestantes (19/43) e 24 gestantes (24/43), todas sem evidência de doença clínica. Para determinação da fase gestacional foi realizada através das medidas dos fetos. Para análise de uma prévia infecção foram avaliados anticorpos anti-Leptospira,por meio do teste de aglutinação microscópica (MAT). Após a exposição do endométrio,com auxílio de um punch de 8 mm foram retirados fragmentos de endométrio (explantes)foram retirados nas regiões intercarunculares. O processamento dos explantes endometriais ocorreu em placas de cultura celular de 24 poços. As soluções adicionadas sobre os explantes foram as seguintes: a) meio controle, contendo 2 mL de solução de RPMI; b) meio RPMI, contendo 1μg/mL de LPS de Escherichia coli; c) meio EMJH com inóculo de Leptospira interrogans sorovar Hardjoprajitno na concentração de 108 leptospiras por mL. Em seguida,as placas foram incubadas em estufa a 37ºC com 5% de CO2 permanecendo por 24 horas. Após esse período, os tecidos endometriais foram pesados e os sobrenadantes foram recolhidos e subsequentemente testados para determinação dos perfis de produção das interleucinas 1β e 6 pelo Kits de ELISA. Em relação ao desafio com 1μg/mL de LPS, tanto explantes das vacas não gestantes como gestantes montaram uma resposta frente ao desafio, com aumento significativo da produção de IL-6 e IL-1β em relação aos controles. No desafio com Leptospira, os explantes de vacas não gestantes e gestantes, houve aumento na concentração de IL-1β. Entretanto, somente explantes das vacas não gestantes houve aumento de IL-6 em relação aos controles. Na avaliação individual das fases de gestação, somente na fase inicial (primeiro trimestre) ocorreu produção de IL-6 significativa, diferente do observado com IL-1β, sendo que ocorreu diferença significativa na produção desta citocina na fase final de gestação, no desafio com 1μg/mL de LPS de E.coli. Já no desafio com Leptospira não houve diferença significativa entre as fases gestacionais. Conclui-se que ocorre maior estimulação da produção de citocinas do endometrio de vacas reagentes, nos desafios ao LPS e à Leptospira; menor estimulação da produção de IL-6 ao desafio com Leptospira em vacas gestantes; e maior estimulação na fase inicial e final de gestação no desafio com LPS de E.coli e nenhuma diferença significativa entre as fases gestacionais no desafio com Leptospira
G L Walker - One of the best experts on this subject based on the ideXlab platform.
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effect of calcium source dietary calcium concentration and Gestation Phase on various bone characteristics in gestating gilts
Journal of Animal Science, 1993Co-Authors: G L Walker, D M Danielson, E R Peo, R F MummAbstract:Sixty gravid crossbred gilts were allotted to a 2 x 3 x 2 factorial arrangement of treatments: two Ca sources (sun-cured alfalfa meal and CaC03), three dietary concentrations of Ca (50, 75, and 100% of NRC requirements), and two Phases of Gestation (55 and 105 d). The objectives were to determine the effect of Ca source, dietary Ca concen- tration, and Gestation Phase on bone characteristics (bone breaking strength, bone ash percentage, bone density, and bone ash density in the rib, thoracic, and coccygeal bones), to correlate bone responses to determine relative bone activity, and to determine reliability of the coccygeal bones as indicators of Ca status in the body. At 55 d, rib strength and coccygeal ash content were lower (P < .01) than at 105 d of Gestation. A Gestation Phase x Ca concentration (P < .0 5 ) interaction occurred. As Ca concentration in- creased, thoracic strength and rib ash responded quadratically during each Gestation Phase, for which at 55 d a minima and at 105 d a maxima was produced at 75% of NRC. A Ca source x Ca concentra- tion (P < .05) interaction occurred. Gilts fed alfalfa had the lowest rib bone and ash density when fed 75% of NRC for Ca, whereas gilts fed CaC03 were highest at this level of Ca compared with the other concentra- tions. Generally, all bones were positively correlated with respect to their response to dietary Ca concentra- tion. Few negative correlations were observed. At this level of physiological maturity, there was no effect of Ca source and little effect of Gestation Phase on the bone variables measured at the dietary Ca concentra- tions used in this experiment. The rib and thoracic bones seem to be the most responsive to dietary Ca concentration.
Anita E Hendrickson - One of the best experts on this subject based on the ideXlab platform.
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development of the primate area of high acuity 3 temporal relationships between pit formation retinal elongation and cone packing
Visual Neuroscience, 2005Co-Authors: Alan D Springer, Anita E HendricksonAbstract:By establishing an avascular, highly elastic, region within the fetal area of high acuity (AHA), the developing primate eye has created a unique substrate on which the mechanical forces of intraocular pressure (IOP) and growth-induced retinal stretch (stretch) can act. We proposed (Springer & Hendrickson, 2004b) that these forces generate both the pit and high cone density found in the adult AHA. In this paper, we use quantitative measures to determine the temporal relationships between nasal and temporal retinal elongation, changes in pit depth, cone packing, and cone morphology over M. nemestrina retinal development. Retinal length increased rapidly to about 105 days postconception (dpc; Phase 1) and then elongation virtually ceased (Phase 2) until just after birth (180 dpc). Retinal elongation due to stretch resumed during Phase 3 until approximately 315 dpc (4–5 months), after which time the retina appeared mature (Phase 4). The pit appeared during the quiescent Phase 2, suggesting that IOP acts, in conjunction with molecular changes in the inner retina, on the highly elastic, avascular, AHA to generate a deep, narrow pit and causes inner retinal cellular displacements. Subsequently (Phase 3), the pit widened, became 50% shallower and central inner retinal lamina thinned slightly due to a small amount of retinal stretch occurring in the AHA. Centripetal movement of cones was minimal until just after birth when the pit reached 88% of its maximal depth. Accelerated cone packing during Phase 3 was temporally correlated with increased stretch. A slight stretching of the central inner retina generates “lift” forces that cause the pit to become shallower and wider. In turn, these “lift” forces draw cones toward the center of the AHA (Springer, 1999). Localized changes in cone morphology associated with packing, included smaller cell body size, a change from a monolayer to a multilayered mound of cell bodies, elongation of inner segments and tilting of the apical portion toward the AHA. These changes began in cones overlying the edges of the pit, not its center. Henle cone axons formed initially in association with centrifugal displacement of the inner retina during pit formation, with an additional subsequent elongation due to cones moving centripetally. An integrated, two-factor model of AHA formation is presented. Initially, during the second half of Gestation (Phase 2), IOP acts on the hyperelastic avascular zone of the AHA to generate a deep pit in the inner retina. In the first 4 months after birth (Phase 3), central retinal stretch generates tensile “lift” forces that remodel the pit and pack cones by drawing them toward the AHA center.
Christine Aurich - One of the best experts on this subject based on the ideXlab platform.
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changes in blood pressure heart rate and blood profile in mares during the last 3 months of Gestation and the peripartum period
Theriogenology, 2016Co-Authors: Christina Nagel, Lisa Trenk, Jorg Aurich, Manuela Wulf, Christine AurichAbstract:In this study, peripartum changes in complete blood count, plasma electrolyte concentrations, blood pressure, heart rate, and heart rate variability (HRV) were determined in pregnant Warmblood mares (n = 10). Blood was collected from Days 245 to 330 of Gestation (Phase A), 2Days 3 to 1 before foaling (Phase B), repeatedly within 12 hours after foaling (Phase C), and on Days 1 to 3 postpartum (Phase D). On the same days as blood collection, blood pressure and cardiac beat-to-beat intervals were measured and time domain HRV variables were calculated. Blood pressure decreased during the past 3 months of Gestation, reached a nadir at foaling and increased rapidly thereafter (P < 0.001). Heart rate increased in Phase A, reached a maximum in Phase B, and decreased directly after foaling (P < 0.001) while HRV increased transiently after foaling (P < 0.001). The number of polymorphonuclear granulocytes was higher during Phases B, C, and D than that during Phase A (P < 0.001) and total leukocyte numbers peaked in Phase C (P < 0.001). Erythrocyte counts and hematocrit increased immediately after foaling with a rapid decrease thereafter (P < 0.001), while plasma total protein was highest 1 hour after foaling (P < 0.001). Sodium and chloride concentrations increased from Phases A to C and decreased in Phase D (P < 0.001). Calcium concentrations were lowest immediately after foaling. In conclusion, changes in cardiovascular function and a transient hemoconcentration occur in peripartum mares. These changes may favor adequate uterine perfusion.