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1.
During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.  相似文献   
2.
Non‐steroidal anti‐inflammatory drugs may potentiate the opioid induced reduction in volatile anaesthetic requirements ( Gomez de Segura et al. 1998 ). This study determined the reduction in the MAC of isoflurane (ISO) produced by ketoprofen (KETO) in dogs anaesthetized with fentanyl (FENT) and ISO. Six healthy female crossbred dogs, weighing 13.5 ± 1.3 (mean ± SD) kg and aged 3.0 ± 0.9 years were studied. Approval of the study was obtained from the institutional ethics committee. Anaesthesia was induced in all dogs via a facemask with 5% ISO in 5 L minute?1 oxygen. The dogs' trachea were intubated and lungs were ventilated to maintain normocapnia (Pe ′CO2 4.7–6 kPa, 35–45 mm Hg). A heating pad was used to maintain body temperature. The animals were anaesthetized four times at one week intervals with the following anaesthetic and analgesic protocols randomly administered. Study 1, MAC (ISO); Isoflurane MAC. Study 2, MAC (ISO + FENT); dogs anaesthetized with ISO received a loading dose of 30 µg kg?1 FENT IV over 20 minutes followed by a maintenance infusion of 0.2 µg kg?1 minute?1 FENT. Study 3, MAC (ISO + FENT + KETO1); as study 2 plus 1 mg kg?1 KETO. Study 4, MAC (ISO + FENT + KETO2); as study 2 plus 2 mg kg?1 KETO. The MAC was determined in duplicate by applying a standard electrical stimulus (50 V, 50 H2 over 60 seconds via two needles placed SC over the tarsus). The stimulus was applied 15 minutes after every step change in anesthetic concentration. The Wilcoxon test was applied to data to determine significant differences among MAC measurements. Fentanyl significantly decreased MAC (ISO) from 1.27% ± 0.02% to 0.73% ± 0.08%, a reduction of 42% (p < 0.05). Ketoprofen 1 mg kg?1 further decreased the MAC value (although not statistically significantly) with a reduction of 47% from MAC (ISO) (0.67% ± 0.13%) and 8% from MAC (ISO + FENT). When KETO 2 mg kg?1 was given, the reduction in MAC was 50% compared to MAC (ISO) (0.63% ± 0.08%; p < 0.05) and 14% compared to MAC (ISO + FENT) p < 0.05. Administration of KETO further reduces MAC (ISO) compared to levels observed with FENT alone. The observed reduction may have clinical advantages.  相似文献   
3.
An experiment was done to determine manure output, N and P excretion, and apparent digestibilities of AA, CP, P, and DM in growing pigs fed barley-based diets containing micronized or raw peas with or without supplementation with enzyme containing primarily beta-glucanase and phytase (Biogal S+). Eight barrows (21.5 +/- 1.2 kg of initial BW) fitted with T-cannulas at the distal ileum were used in a 40-d trial and housed in metabolism cages. Pigs were assigned in a replicated 4 x 4 Latin square design to 4 experimental diets: 1) barley-raw peas control (BRP), 2) barley-micronized peas (BMP), 3) BRP plus enzyme, and 4) BMP plus enzyme (BMP+E). Pigs received 2.6 times maintenance energy requirements based on BW at the beginning of each experimental period. During each experimental period, pigs were acclimatized to their respective diets for 5 d followed by a 3-d period of total fecal and urine collection and another 2-d period of ileal digesta collection. Samples were analyzed for DM, AA (diets and digesta only), N, and P. Wet fecal output of BRP plus enzyme-fed pigs tended to be lower (P = 0.07) than the amount produced by BMP-fed pigs. The amounts of dry feces and urine produced were not different among treatments (P > 0.10). Supplementing the BRP and BMP diet with enzyme increased (P = 0.002) the daily P retained per pig. Pigs fed the enzyme-supplemented diets tended to have lower (P = 0.06) fecal P excretion and greater urinary P excretion (P = 0.001) compared with pigs fed the nonsupplemented diets, but total P excretion was not influenced by diet (P > 0.10). Pigs fed the BMP+E diet retained more (P = 0.006) N per day than pigs fed the BMP diet. However, N excretion was not influenced by dietary treatment (P > 0.10), although BMP+E-fed pigs excreted 13.2% less N in the feces compared with those fed the nonenzyme supplemented controls. Inclusion of micronized peas with or without enzyme supplementation did not affect urinary or fecal N excretion (P > 0.10) compared with the BRP. Dietary treatment had no effect (P > 0.10) on ileal or fecal DM or CP digestibilities. Apparent ileal digestibilities of AA were usually lower (P < 0.05) in the BRP diet compared with the other diets. Enzyme supplementation improved P digestibility at the ileal and fecal level. The current results indicate that utilizing micronized peas in barley-based pig grower diets enhances P retention.  相似文献   
4.
This study was aimed at assessing the changes in sperm motion patterns and the percentage of acrosome reaction (AR) in domestic cat semen after treatment with either ionomycin or progesterone (P4). Ten ejaculates were collected from five tomcats using an artificial vagina, and were diluted, centrifuged and resuspended in a capacitation medium. Samples were evaluated and divided into seven equal aliquots and, after 2 h at 25°C, were incubated for 30 min at 38°C in 5% CO2 and then analyzed. Computer-assisted sperm analysis and a combination of three fluorescent probes were used to assess sperm plasma, acrosomal membrane integrity and mitochondrial transmembrane potential. Thirty minutes after the start of incubation, P4 was added (10 μg/ml) to the P1 group. Groups P2 and P3 were supplemented with P4 (10 and 20 μg/ml, respectively) only after 2 h of incubation, and groups I1 and I2 were supplemented with ionomycin (4 and 8 μ m , respectively) 2 h after incubation. Group E was supplemented with ethanol (0.6%) at 2 h after incubation and group C received no supplementation. Ionomycin and P4 treatments led to a hyperactivation-like sperm motion and an increase (p < 0.05) in the percentage of AR. Although a higher (p < 0.05) percentage of AR was obtained in group I2 when compared with all P4 groups, a decrease (p < 0.05) in total and progressive motility was observed in I2 group. As I1 group was similar to I2 to induce AR without diminishing sperm motility, we can conclude that ionomycin at 4 μ m seems to be more suitable to trigger AR in domestic cat sperm.  相似文献   
5.
Forty piglets (average body weight = 5.32 kg) were used to investigate the effect of dietary crude protein (CP) content on immunological responses following a challenge with enterotoxigenic Escherichia coli (ETEC) K88. Pigs, housed 4 per pen, were randomly allotted to 2 diets: 1) a high, 225 g/kg CP diet (HCP) or 2) a low, 176 g/kg CP diet (LCP) supplemented with crystalline amino acids. Pigs were orally challenged with 6 mL of an ETEC K88 suspension containing 1010 cfu/mL on d 8 after weaning. Blood samples were collected from 10 pigs (1 pig/pen) on d 7 (at weaning), −24 h, 8 h, 72 h and 7 d after the challenge for determination of plasma urea N (PUN) and serum concentrations of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) and haptoglobin (Hp). Tumor necrosis factor alpha, IL-1β and Hp were measured as indicators of inflammatory responses. The concentrations of serum TNF-α at 8 h, 72 h and 7 d after challenge were similar to the level observed at 24 h before challenge but higher (P < 0.05) than the weaning level. Pigs fed the LCP diet had lower (P = 0.032) concentrations of IL-1β (72 vs. 116 pg/mL) at 8 h post-challenge compared with those fed the HCP diet. Likewise, pigs fed the LCP diet tended to have lower (P = 0.088) concentration of Hp (9 vs. 25 mg/dL) compared with those fed the HCP diet at 8 h post-challenge. Compared with the weaning concentration, PUN concentration at 72 h after ETEC challenge was higher (P < 0.05) in pigs fed the HCP diet. The results indicate that the LCP diet supplemented with crystalline amino acids reduced inflammatory responses, as indicated by serum IL-1β, in piglets infected with ETEC K88.  相似文献   
6.
An experiment was conducted to determine growth performance, carcass characteristics, and fat quality of growing-finishing pigs fed diets based on short-season corn hybrids. Twenty-four individually housed, Cotswold, growing pigs with an initial BW of 41.4 (SD = 1.4) kg were blocked by BW and sex and randomly allotted from within block to 1 of 3 diets to give 8 replicate pigs per diet. Experimental diets consisted of a control based on barley and 2 diets based on corn as the main energy sources. A 3-phase feeding program for 20 to 50 kg (phase I), 50 to 80 kg (phase II), and 80 to 110 kg (phase III) of BW was used. Diets for each phase contained approximately 3.5 Mcal/kg of DE, with total lysine of 0.95, 0.75, and 0.64% in phase I, II, and III diets, respectively. Average daily gain, ADFI, and G:F were monitored weekly during each phase. Pigs were slaughtered after reaching a minimum BW of 100 kg to determine carcass characteristics. There were no effects of diet on ADG, ADFI, and G:F (0.45 +/- 0.02, 0.34 +/- 0.02, and 0.31 +/- 0.02 for phase I, II, and III, respectively). Carcass length, dressing percent, LM area, loin depth, backfat thickness, belly firmness, and L*, b*, and a* fat color were not different across dietary treatments. Pigs fed one corn variety had no differences in fatty acid profile with barley-fed pigs, whereas those fed the other variety of corn had a greater (P < 0.05) concentration of PUFA in their backfat. The results indicate that growth performance, carcass characteristics, and fat quality of pigs fed diets based on short-season corn hybrids and those fed the barley-based diet were not different.  相似文献   
7.
The kodkod population is in constant decrease and the somatic cell nuclear transfer (SCNT) might help to preserve the genetic pool of this species. The cell cycle synchronization of donor cells plays a crucial role in SCNT. The objective of this research was to evaluate two different methods for quiescence induction, serum starvation (SS) and contact inhibition (CI), both for 1, 3 and 5 days, on skin fibroblast from domestic cat and kodkod. Flow cytometry analysis revealed that in domestic cat, SS and CI, both at 3 and 5 days, increased the percentage of fibroblasts in G0/G1 compared to growing cells (GC) (p < .05). In kodkod, only SS for 3 and 5 days and CI for 1 and 3 days increased the percentage of fibroblasts in G0/G1 compared to GC (p < .05). Viability analysis by differential staining revealed that SS for 5 days decreased the proportion of live fibroblasts in domestic cat and kodkod (p < .05). Regarding gene expression analysis, in domestic cat fibroblasts, no differences were found in the BAX/BCL2 ratio in SS and CI (both at 1, 3 and 5 days) compared to GC. In kodkod fibroblasts, BAX/BCL2 ratio was increased in CI at 3 and 5 days compared to SS at 3 and 5 days (p < .05). In conclusion, in kodkod fibroblasts SS for 5 days and CI after 3 days might have a negative impact on cellular viability. According to these results, we suggest SS for 3 days for cell cycle synchronization in kodkod fibroblasts.  相似文献   
8.
Stem cells have been postulated as responsible for cell regeneration in highly and continuously regenerative tissues such as the endometrium. Few studies in cattle have identified and specified the presence of stem cells in the endometrium during the oestrous cycle. The aim of this study was to investigate the presence of mesenchymal stem cells (MSCs) in the bovine endometrium during the follicular phase (FP) of the oestrous cycle. Uterine tissue was collected in the time‐frame comprising day 18 of the cycle and ovulation (day 0). We isolated, cultured and expanded four primary cell lines from endometrium and identified byRT‐qPCR the expression of OCT4, SOX2 but not NANOG (undifferentiated/embryonic markers), CD44 (MSCs marker) and c‐KIT (stem cell marker) genes; and the encoded Oct4, Sox2 and Cd44 proteins by Western blot or immunostaining of paraffin‐embedded tissue in endometrium. We demonstrated that cells isolated from bovine endometrium displayed essentially the same gene expression pattern; however, at the protein level, Oct4 and Cd44 were not detected. Besides, they showed typical functional characteristics of MSCs such as fibroblast‐like morphology, plastic adherence, high proliferative capacity, clone formation in vitro and the ability to differentiate into chondrogenic, osteogenic and adipogenic lineages. We obtained for the first time an extensive characterization of undifferentiated cells populations contained in the bovine endometrium during the FP of the oestrous cycle.  相似文献   
9.
Cryopreservation causes damage to spermatozoa, and methods minimizing this damage are therefore needed. Although much discussed, seminal plasma removal has become an alternative to improve sperm quality and viability after freezing and has been applied to different species in attempt to obtain good results. The objective of this study was to evaluate semen quality in buffaloes submitted to two methods for seminal plasma removal (filtration and centrifugation). Semen samples were collected from seven Murrah buffalo bulls (Bubalus bubalis) once a week for 8 weeks. Each ejaculate was divided into three groups: control (presence of seminal plasma), centrifugation and filtration. Sperm kinetics was evaluated with the computer‐assisted sperm analysis (CASA) system. Plasmalemma and acrosomal membrane integrity, mitochondrial membrane potential and reactive oxygen species (ROS) were measured by flow cytometry, and lipid peroxidation was evaluated by the thiobarbituric acid reactive substances (TBARS) assay. Seminal plasma removal did not improve sperm kinetics compared to the control group. Centrifugation increased the number of cells with damaged acrosomal membranes (0.77 ± 0.05) and filtration caused greater plasmalemma and acrosomal membrane damage (22.18 ± 1.07). No difference in the mitochondrial membrane potential was observed between groups. In contrast, ROS production was higher in the centrifugation group compared to the control and filtration groups, although no differences in TBARS formation were detected. In conclusion, seminal plasma removal did not improve the quality of thawed buffalo semen compared to control in terms of sperm kinetics, membrane integrity, mitochondrial membrane potential or lipid peroxidation.  相似文献   
10.
During cryopreservation, sperm was submitted to an increase in reactive oxygen species generation. This work aimed to improve the quality of frozen equine sperm after the addition of antioxidants lactoferrin (Lf) and catalase (Cat) to a freezing extender. Semen from six stallions was frozen with the extenders: F1) control, INRA 82 freezing extender, F2) F1 + 500 μg/ml Lf and F3) F1 + 200 IU/ml Cat. After thawing, sperm motility parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome‐reacted sperm were evaluated with a computer‐assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite, hydroperoxide and iron concentrations of frozen semen were measured with spectrophotometry. The percentage of functional membrane sperm treated with Lf was higher (50.7% ± 11.6%) compared to that of the control (37.6% ± 15.6%), while the iron (61.4 ± 11.6 vs 73.3 ± 13.8 mg/dl) and nitrite concentrations (16.3 ± 7.1 vs 25.9 ± 4.2 μM/μg protein) were lower, respectively (p < .05). Thus, it can be suggested that Lf protect stallion spermatozoon during freezing as it has increased the percentage of sperm with functional membrane and decreased the lipid oxidant agents.  相似文献   
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