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AFC de Andrade RP de Arruda ECC Celeghini J Nascimento SMMK Martins CF Raphael AS Moretti 《Reproduction in domestic animals》2007,42(2):190-194
The purpose of this study was to validate a technique for simultaneous evaluation of the plasma, acrosomal and mitochondrial membranes in boar spermatozoa, using an association of fluorescent probes: Propidium iodide (PI), fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and JC-1. Three ejaculates from each of four different boars, all showing motility >or=80% and abnormal morphology 相似文献
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ECC Celeghini RP de Arruda AFC de Andrade J Nascimento CF Raphael 《Reproduction in domestic animals》2007,42(5):479-488
This experiment was performed to develop and validate practical techniques for simultaneous evaluation of the integrity of plasma and acrosomal membranes, as well as mitochondrial function in bovine spermatozoa using associations of fluorescent probes. Four protocols of fluorescent probes association were defined: protocol 1: propidium iodide (PI), fluorescein isothiocyanate‐conjugated Pisum sativum agglutinin (FITC‐PSA) and rhodamine 123; protocol 2: PI, FITC‐PSA and MitoTracker Green FM (MITO); protocol 3: PI, Hoechst 33342 (H342), FITC‐PSA and CMXRos; and protocol 4: PI, H342, FITC‐PSA and JC‐1. Three ejaculates from each of the four bulls (n = 12) were utilized, showing sperm motility ≥80% and abnormal morphology ≤10%. The semen was diluted in Modified Tyrode’s medium (TALP) (25 × 106 spermatozoa/ml) and split into two aliquots, one sample was flash‐frozen in liquid nitrogen and thawed. Samples for three treatments were prepared with the following ratio of fresh semen : flash‐frozen semen: 100 : 0, 50 : 50 and 0 : 100. Samples were stained in all four protocols and evaluated by epifluorescence microscopy. Protocol 1 did not result in a satisfactory stain, so it could not be validated. Protocols 2, 3 and 4 were validated and showed high determination coefficient to plasma membrane integrity (R2 = 0.95, 0.93 and 0.92, respectively), acrosome integrity (R2 = 0.95, 0.92 and 0.91, respectively) and mitochondrial function (R2 = 0.84, 0.93 and R2 = 0.93, respectively). These techniques are efficient for the simultaneous integrity evaluation of plasma and acrosomal membranes and mitochondrial function in bovine spermatozoa. However, JC‐1 has an advantage over MITO and CMXRos, as it separates two cell populations with high and low mitochondrial membrane potential. 相似文献
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An unexpected three-stage melting transition has been observed in two-dimensional (2D) free-standing liquid-crystal films by in situ electron-diffraction and optical-reflectivity measurements. These data suggest the existence of two phases between the 2D solid and liquid: a hexatic phase and, at a higher temperature, an intermediate liquid phase with hexatic-like positional correlations ( approximately 40 angstroms) but no long-range orientational order. Previous high-resolution heat-capacity measurements have revealed a divergent-like anomaly at the hexatic-liquid transition that sharply contradicts the predictions of 2D melting theories. The observation of an intermediate isotropic phase may alter our understanding of 2D melting and lead to reconciliation between current experiments and theories. 相似文献
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Pait CF 《Science (New York, N.Y.)》1963,142(3598):1422-1424
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ER da Cunha CF Martins CG Silva HC Bessler SN Báo 《Reproduction in domestic animals》2014,49(5):806-812
The objective of this work was to study cellular types that did not participated in the gastrulation process, amniotic fluid cells (AFCs) and umbilical cord cells (UCCs), in conditions of long‐term culture and cryopreserved with different solutions. The AFCs and UCCs were used in a comparative study with ear fibroblast cells (EFCs) that were cultured in vitro until 20 cellular passages and cryopreserved in 10% dimethylsulphoxide (DMSO), 5% dimethyl formamide (DMF) and 7% glycerol (Gly) solutions. The cellular viability, ultrastructure, DNA fragmentation and chromosome stability were evaluated to determine the cellular type most resistant. In all cell types, it was possible to evaluate the AFCs until 15 passages and UCCs until 20 passages with different periods of cellular growth to reach the confluence phase. Solutions containing 10% DMSO ensured viability of 90.33 ± 5.58%, 90.56 ± 4.40% and 81.90 ± 3.31%, respectively for EFCs, AFCs and UCCs, being significantly more efficient and with less variation than other cryoprotectant solutions. The AFCs were more sensitive to cryopreservation and presented low viability rate at the passage 20 (17.2 ± 8.87%). There was no change in karyotype and nuclear fragmentation was low in all cellular passages studied. With the scanning electron analysis was possible the characterization of AFCs and UCCs in suspension. The three cellular types of cells presented different shapes and characteristics on the surface. The results demonstrate that bovine AFCs and UCCs can be isolated, cultured in vitro and cryopreserved in 10% DMSO, not causing damage to DNA and chromosomes. The UCCs were more resistant than AFCs in all aspects. 相似文献
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Abstract AIM: To compare the efficacy of oxytocin given once daily, either I/V or I/M, on Days 7–14 post-ovulation, on the expression of oestrus in mares through to 65 days post-ovulation. METHODS: Eighteen mares of various breeds that were displaying normal oestrous cycles were randomly assigned to one of three treatment groups on the day of ovulation (Day 0), detected using transrectal ultrasonography. Mares in the control group (n = 6) were given 1 mL saline I/V; mares in the I/V and I/M groups (n = 6 per group) were injected with 10 IU oxytocin I/V and I/M, respectively. All treatments were given once daily on Days 7–14. Mares were teased by a stallion three times per week, up to 65 days post-ovulation, to detect oestrous or dioestrous behaviour. Ovarian follicular and luteal activity were monitored using transrectal ultrasonography three times weekly, and daily when a follicle >30 mm diameter was present until ovulation. Blood samples were collected weekly for analysis of concentrations of progesterone in serum. Prolonged dioestrus was defined as a period of >30 days of dioestrous behaviour after Day 0, confirmed by detection of corpora lutea and concentrations of progesterone in serum >4 nmol/L. RESULTS: Overall, 8/18 (44%) mares showed prolonged dioestrus. These included 2/6 (33%) mares in the control group, compared with 5/6 (83%) and 1/6 (16%) mares in the I/V and I/M groups, respectively (p = 0.11). The median duration of the first dioestrus was longer for the I/V group (64 (min 16, max 66) days) compared with the control group (18 (min 12, max 64) days) (p = 0.05), but was not different between the control group and the I/M group (16 (min 13, max 65) days) (p = 0.57). For all mares there was strong agreement between teasing behaviours, ultrasonographic assessment of ovarian activity, and concentration of progesterone in serum. CONCLUSIONS AND CLINICAL RELEVANCE: This study found that low doses of oxytocin did not increase the proportion of mares with prolonged dioestrus, compared with controls, although I/V oxytocin did increase the median duration of dioestrus. The results must be interpreted with some caution as group numbers were small, and a variety of breeds were used. Further investigation of oxytocin given I/V may be warranted as a potential method of oestrus suppression in mares exhibiting oestrous cycles that is low cost, safe and well-tolerated, and potentially reversible with prostaglandin. 相似文献
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CF Lúcio LCG Silva JA Rodrigues GAL Veiga CI Vannucchi 《Reproduction in domestic animals》2009,44(S2):133-136
There has been limited investigation of parturition in the bitch and there is little information published on clinical and obstetrical examination other than opinion and anecdote. While there are substantial data on haemodynamic and vascular changes during normal parturition in humans, little is known about the physiological events in the dog. This study was aimed at maternal haemodynamic changes occurring during normal parturition and to investigate how these were modified in bitches with dystocia (DYST) treated either medically or via assisted delivery and caesarean operation. Three groups of 10 bitches were investigated; those with normal parturition, those with DYST corrected by manipulative assistance or caesarean operation and those with uterine inertia treated by oxytocin administration. Heart rate, systolic and diastolic blood pressure, electrocardiogram and blood glucose concentration were measured pre-partum, intra-partum, immediately after parturition and 1 h later. Heart rate was high at all times throughout the study and the majority of bitches had normal sinus rhythm. Blood pressure was generally within the normal range, and although systolic and diastolic blood pressure was highest during the intra-partum period and sometimes during the immediate post-partum period, there were no significant differences between groups. All bitches had blood glucose concentrations within the normal range throughout the study although pre-partum concentrations were statistically lower than many of the other time periods. The study provides useful physiological data that will facilitate monitoring and clinical management of bitches throughout normal parturition and DYST. 相似文献