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1.
The presented study was designed to elucidate whether the cholinergic mechanisms control ovine antral slow waves in various physiological conditions, including feeding and various phases of migrating myoelectric complex (MMC). The investigations were carried out on six adult sheep of Polish Merino breed with seven bipolar electrodes surgically implanted onto the antral and small intestinal wall. In the course of chronic experiments, the myoelectric activity was recorded from these regions using the multichannel electroencephalograph. Experiments were performed on 48 h fasted and non-fasted animals. During some of these experiments, sheep were fed with standard fodder. During control experiments 0.15 M NaCl was slowly administered i.v. through the indwelling catheter and during other experiment, hexamethonium bromide (2.0 and 5.0 mg/kg). atropine sulfate (0.02; 0.1; 0.5 and 1.5 mg/kg) and pirenzepine dihydrochloride (0.02; 0.5 and 2.0 mg/kg) were administered i.v. during phase 1-2a or 2b MMC. The drugs were also given in combinations. The recordings were analysed and the antral slow wave amplitudes and frequencies were calculated. Unlike the slow wave amplitude, either feeding or the anticholinergic drugs significantly increased slow wave frequency, especially when the given procedure was started during phase 2b MMC. The most pronounced effects were observed after hexamethonium given alone or in combinations. Thus, the cholinergic system modulates antral slow wave frequency in sheep.  相似文献   
2.
We investigated the influence of heparin, one of the extracellular matrix (ECM) components, on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by bovine peripheral blood mononuclear cells (PBMC) and monocytes left to adhere for 2 (freshly adherent monocytes) and 48 h (resting monocytes), activated with Salmonella typhimurium lipopolysaccharide (LPS). After 24-h stimulation with LPS, heparin (100 microg/ml) increased (by about 40%) NO production by peripheral blood mononuclear cells and by freshly adherent monocytes. However, it did not change NO synthesis by the resting monocytes. Unlike its influence on NO level, heparin diminished TNF-alpha production by PBMC and monocytes stimulated with LPS. Microscopical examination of PBMC stained with biotin-labeled heparin, showed that both lymphocytes and monocytes were able to bind this glycosaminoglycan. We suggest that heparin, as a component of ECM, modulates the early response of monocytes to exogenous stimuli.  相似文献   
3.
The effects of exposure of human erythrocytes to different concentrations of 4-chloro-2-methylphenoxyacetic acid (MCPA) and its metabolite—2,4-dimethylphenol (2,4-DMP) were studied. The investigations concerned mainly the content of glutathione (GSH and GSSG), glutathione peroxidase (GSH-Px), glutathione transferase (GST), and the level of adenine energy charge (AEC). Reactive oxygen species (ROS) such as hydroxyl radical, superoxide anion, hydrogen peroxide, and nitric oxide are produced during normal processes in the cell. Under normal conditions, antioxidant systems of the cell minimize damage caused by ROS. When ROS generation increases to an extent that it overcomes the cellular antioxidant systems, the result is oxidative stress. We observed that MCPA and 2,4-DMP decreased the level of GSH in erythrocytes in comparison with control. MCPA did not affect glutathione peroxidase and glutathione transferase activity, while 2,4-DMP increased their activity. 2,4-DMP decreased the level of ATP and increased the content of ADP and AMP, leading to the fall of the level of AEC. MCPA and 2,4-DMP transform hemoglobin into methemoglobin, thus preventing oxygen transport. Comparison of the toxicity of MCPA and 2,4-DMP revealed that the most prominent changes occurred in human erythrocytes incubated with 2,4-DMP.  相似文献   
4.
The aim of this study was to assess the influence of growth on the pharmacokinetics of sodium salicylate (SS) in male turkeys. SS was administered intravenously at a dose of 50 mg/kg. Plasma drug concentrations were assessed by high‐performance liquid chromatography, and pharmacokinetic parameters were calculated by noncompartmental analysis. As the age increased from 6 to 13 weeks (body weight increase from 2.35 to 9.43 kg), median body clearance decreased from 1.34 to 0.87 ml/min/kg. This caused a significant increase in the median mean residence time from 3.42 to 4.44 hr. Elimination phase proved to be biphasic and two elimination half‐lives (T1/2el) were distinguished. Whereas T1/2el1 was found to increase with age by 128%, T1/2el2 represented a later but faster and less age‐dependent phase of elimination (increase by 56% in the respective groups). Volume of distribution decreased with age. These effects may lead to different therapeutic response to SS in turkeys of different age and body weights.  相似文献   
5.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non‐manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non‐manipulated way.  相似文献   
6.
Establishment of European eel (Anguilla anguilla) hatchery production will rely on selectively bred individuals that produce progeny with the best traits in successive generations. As such, this study used a quantitative genetic breeding design, between four females and nine males (four wild‐caught and five cultured), to investigate the effect of paternal origin (wild‐caught vs. cultured) and quantify the relative importance of parental effects, including genetic compatibility, on early life history (ELH) performance traits (i.e. fertilization success, embryonic survival at 32 hr post‐fertilization, hatch success and larval deformities at 2 days post‐hatch) of European eel. Wild‐caught males had higher (56%) spermatocrit values than cultured males (45%), while fertilization success, embryonic survival, hatch success and larval deformities were not significantly impacted by paternal origin. This demonstrates that short‐term domestication of male eels does not negatively affect offspring quality and enables the consideration of cultured male broodstock in future breeding programmes. Moreover, paternity significantly explained 9.5% of the variability in embryonic survival, providing further evidence that paternal effects need to be taken into consideration in assisted reproduction protocols. Furthermore, maternity significantly explained 54.8% of the variation for fertilization success, 61.7% for embryonic survival, 88.1% for hatching success and 62.8% for larval deformities, validating that maternity is a major factor influencing these “critical” ELH traits. At last, the parental interaction explained 12.8% of the variation for fertilization success, 8.3% for embryonic survival, 4.5% for hatch success and 20.5% for larval deformities. Thus, we conclude that eggs of one female can develop more successfully when crossed with a compatible male, highlighting the importance of mate choice for successful propagation of high‐quality offspring. Together, this knowledge will improve early offspring performance, leading to future breeding programmes for this critically endangered and economically important species.  相似文献   
7.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
8.
Aquaculture production relies on controlled management of gametogenesis, especially in species where assisted reproduction is needed for obtaining gametes in captivity. The present study used human chorionic gonadotropin (hCG) treatments to induce and sustain spermatogenesis in European eel (Anguilla anguilla). The aim was to evaluate effects of strip-spawning timing (12 vs. 24 hr) after weekly administration of hCG and the necessity of a primer dose (in addition to weekly hormonal treatment) prior to strip spawning (primer vs. no-primer) on sperm quality parameters. Sperm parameters included milt production (weight), density and sperm kinematics at Week 9, 11 and 13 after onset of treatment. Spermiation commenced in 11.5% of males in Week 5 and by Week 9, and all males produced milt. Male weight, milt production, sperm density and spermatocrit did not differ among hormonal treatments during the experimental period. Overall, male weight decreased from 106.3 to 93.0 g, milt weight increased from 3.5 to 5.4 g, sperm density counts decreased from 11.7 × 109 to 10.5 × 109 cells/ml, and spermatocrit decreased from 46.5% to 40.5%. Furthermore, spermatocrit was positively related to haemocytometer counts (R2 = .86, p < .001), providing a reliable indicator of sperm density. Differences in sperm kinematics were observed depending on strip-spawning timing after hormonal injection (12 vs. 24 hr) but with no consistent pattern. These sperm quality parameters also did not consistently differ between the no-primer and primer treatments. Considering that each male may be stripped 4–5 times over the 2–3 months spawning season, omitting the primer would reduce animal handling, material costs and labour intensity, while sustaining high-quality sperm production.  相似文献   
9.
Cutaneous leiomyosarcomas are malignant mesenchymal tumors of smooth muscle origin and are reported occasionally in avian species. A 14-y-old male laboratory White Carneau pigeon (Columba livia) was presented for surgical excision of a cervical soft tissue mass. Ultrasonography with color flow Doppler imaging revealed multiple cavitations of mixed echogenicity within the mass and vascularization. Histologically, the dermis and subcutis were expanded by a densely cellular multinodular mass comprised of fusiform cells forming haphazardly arranged broad streams and short interwoven bundles, often surrounding blood vessels and variably sized cavitations. Neoplastic cells were strongly immunopositive for desmin and α–smooth muscle actin, and negative for pancytokeratin, S100, and von Willebrand factor. Based on histopathology and IHC findings, the cutaneous mass was diagnosed as leiomyosarcoma (LMS). The pigeon died 312 d post-operatively. Postmortem examination revealed masses infiltrating the left and right pulmonary airways and one hepatic nodule, but no regrowth at the surgical site. Histologic and IHC evaluation of the pulmonary and hepatic masses were consistent with LMS, representing metastatic foci from the primary cutaneous LMS. Our case highlights the malignant behavior and histomorphologic features of cutaneous LMS in an avian species.  相似文献   
10.
This study aimed to evaluate the effect of micronized pea seeds introduced into feed mixes for broilers on the slaughter yield, blood lipid parameters, content of fatty acids in selected tissues, and meat quality. The studies involved 150 1‐day‐old Ross 308 chicks split into three groups (for 42 days). The feed rations differed in terms of the source of proteins: in the control group (C), it was post‐extraction soybean meal (SBM) 100%; in group I, SBM 50% and micronized peas 50%; and in group II, micronized peas only, 100%. Irradiated pea seeds added to the feed ration for chicks reduced the fattening grade of carcasses (P < 0.05). Additionally, significant improvement of blood lipid indices was recorded. The share of the irradiated pea seeds in feed mixes decreased the share of saturated fatty acids in the muscles and abdominal fat and had a positive effect on the n‐6/n‐3 ratio, hypocholesterolemic / hypercholesterolemic ratio, as well as the atherogenic and thrombogenic indices (P < 0.05).  相似文献   
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