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41.
Gabriela Halik Andrzej ozicki Agata Koziorzbska Ewa Arkuszewska Kamila Puppel 《Journal of animal physiology and animal nutrition》2019,103(1):1-7
Forty Simmental cows were divided into four groups with 10 per group to investigate the effect of a transition diet supplemented with synthetic β‐carotene and natural carotenoid‐rich feed (pumpkin silage) on chemical composition of the colostrum. The control group (I) was fed grass and maize silage and supplemental concentrates, group II additionally received 400 mg/day/cow of synthetic β‐carotene, in group, III 40% DM of maize silage was replaced with pumpkin silage to increase β‐carotene intake by 400 mg in relation to group I, and in group IV 60% DM of maize silage was replaced with pumpkin silage without adjusting for β‐carotene. Colostrum was collected from the cows within 5 hr of calving to determine colostrum composition, the content of immunoglobulins and carotenoids, total antioxidant status (TAS), the content of some bioactive proteins and the composition of fatty acids. The study showed that the experimental diets had no effect on the gross composition of colostrum. The content of α‐carotene, β‐carotene and violaxanthin was significantly higher in group IV than in group I and that of lutein higher in group IV than in groups I and II. Total antioxidant status of colostrum in group IV was significantly higher than in group I. Groups III and IV were characterized by a higher concentration of immunoglobulin IgG in relation to group I. IgM level in groups II, III and IV was significantly higher than in group I and that in groups III and IV was also higher than in group II. The highest IgA concentration was observed in group IV and the lowest in group I. Lysozyme concentration was higher in group IV compared to groups I and II. The diets had no effect on the total content of SFA, MUFA and PUFA in colostrum. 相似文献
42.
Pharmacokinetic profiles of metamizole (dipyrone) active metabolites in goats and its residues in milk 下载免费PDF全文
Tae Won Kim Andrejs Sitovs Amnart Poapolathep Helen Owen Andrzej Lisowski Zulkyya Abilova Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2018,41(5):699-705
Metamizole (dipyrone, MET) is a nonopioid analgesic drug commonly used in human and veterinary medicine. The aim of this study was to assess two major active metabolites of MET, 4‐methylaminoantipyrin (MAA) and 4‐aminoantipyrin (AA), in goat plasma after intravenous (IV) and intramuscular (IM) administration. In addition, metabolite concentration in milk was monitored after IM injection. Six healthy female goats received MET at a dose of 25 mg/kg by IV and IM routes in a crossover design study. The blood and milk samples were analyzed using HPLC coupled with ultraviolet detector and the plasma vs concentration curves analyzed by a noncompartmental model. In the goat, the MET rapidly converted into MAA and the mean maximum concentration was 183.97 μg/ml (at 0.08 hr) and 51.94 μg/ml (at 0.70 hr) after IV and IM administration, respectively. The area under the curve and mean residual time values were higher in the IM than the IV administered goats. The average concentration of AA was lower than MAA in both groups. Over 1 μg/ml of MAA was found in the milk (at 48 hr) after MET IM administration. In conclusion, IM is considered to be a better administration route in terms of its complete absorption with long persistence in the plasma. However, this therapeutic option should be considered in light of the likelihood of there being milk residue. 相似文献
43.
Janina Skipor Marta Kowalewska Aleksandra Szczepkowska Anna Majewska Tomasz Misztal Marek Jalynski Andrzej P.Herman Katarzyna Zabek 《畜牧与生物技术杂志(英文版)》2018,(1)
Background: Interleukin-1β(IL-1β) is important mediator of inflammatory-induced suppression of reproductive axis at the hypothalamic level. At the beginning of inflammation, the main source of cytokines in the cerebrospinal fluid(CSF) is peripheral circulation, while over time, cytokines produced in the brain are more important. Melatonin has been shown to decrease pro-inflammatory cytokines concentration in the brain. In ewes, melatonin is used to advance the onset of a breading season. Little is known about CSF concentration of IL-1β in ewes and its correlation with plasma during inflammation as well as melatonin action on the concentration of IL-1β in blood plasma and the CSF, and brain barriers permeability in early stage of lipopolysaccharide(LPS)-induced inflammation.Methods: Systemic inflammation was induced through LPS administration in melatonin-and sham-implanted ewes. Blood and CSF samples were collected before and after LPS administration and IL-1β and albumin concentration were measured. To assess the functions of brain barriers albumin quotient(QAlb) was used.Expression of IL-1β(Il1B) and its receptor type Ⅰ(Il1r1) and type Ⅱ(Il1r2) and matrix metalloproteinase(Mmp) 3 and 9 was evaluated in the choroid plexus(CP).Results: Before LPS administration, IL-1β was on the level of 62.0 ± 29.7 pg/mL and 66.4 ± 32.1 pg/mL in plasma and 26.2 ± 5.4 pg/mL and 21.3 ± 8.7 pg/mL in the CSF in sham-and melatonin-implanted group, respectively.Following LPS it increased to 159.3 ± 53.1 pg/mL and 197.8 ± 42.8 pg/mL in plasma and 129.8 ± 54.2 pg/mL and139.6 ± 51.5 pg/mL in the CSF. No correlations was found between plasma and CSF IL-1β concentration after LPS in both groups. The QAlb calculated before LPS and 6 h after was similar in all groups. Melatonin did not affected m RNA expression of Il1B, Il1r1 and Il1r2 in the CP. The m RNA expression of Mmp3 and Mmp9 was not detected.Conclusions: The lack of correlation between plasma and CSF IL-1β concentration indicates that at the beginning of inflammation the local synthesis of IL-1β in the CP is an important source of IL-1β in the CSF. Melatonin from slow-release implants does not affect IL-1β concentration in plasma and CSF in early stage of systemic inflammation. 相似文献
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Background
Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species’ ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations.Results
We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten.Conclusions
Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and structure in stone marten. Analysis of local barriers that reduced dispersal and large scale analyses of genetic structure and demographic history highlight the importance of isolation by distance and forest cover for the past colonization of central Europe by stone marten. This confirmed the hypothesis that human-landscape changes (deforestation) accelerated stone marten expansion, to which climate warming probably has also been contributing over the last few decades.47.
Somatic embryogenesis is the preferred method for cell-to-plant regeneration of grapevine. In this study, we tested the embryogenic capacity of anther-derived calli from 59 grape genotypes, representing a diverse group of Vitis vinifera and hybrid varieties, and hybrids and accessions of non-vinifera Vitis species. Most genotypes were tested on two types of media: MST1 medium, which contained plant growth regulators (PGRs) 2,4-dichlorophenoxyacetic acid (2,4-D) and thidiazuron (TDZ), and MSE medium, which contained 2,4-D and 6-benzylaminopurine (BAP). Twenty-four of the grape genotypes produced embryogenic callus on one or both of these media, eighteen of which have not been reported to form somatic embryos before. The results also suggested that the various PGR combinations are differentially effective at inducing somatic embryos in various classes of grape genotypes. For example, seven of the eight V. vinifera conv. occidentalis varieties brought forth somatic embryos on MSE medium, and three out of four American Vitis genotypes produced somatic embryos on MST1 medium. We could not observe any apparent association between frequency of callus formation and embryogenic capacity of the anthers. 相似文献
48.
Ewa PECKA Zbigniew DOBRZAŃSKI Andrzej ZACHWIEJA Tadeusz SZULC Katarzyna CZYŻ 《Animal Science Journal》2012,83(2):162-168
The aim of the study was to determine the changes in composition and physicochemical features (pH, density, thermostability and acidity) of mare colostrum and milk, and of protein fraction contribution (serum albumin, β-casein, γ-casein, α-lactalbumin, G class immunoglobulins) depending on lactation stage. The research material was colostrum and milk samples from 12 Arabian mares. Colostrum samples were collected within 2 h after parturition and milk samples were collected twice, in the 3rd and 6th weeks of lactation. The level of basic milk components decreased significantly (only lactose content increased) as compared to colostrum. Total bacteria count and somatic cell count decreased significantly with an increase in resistance and urea level. The changes observed were connected to differentiated contribution of particular protein fractions and their relative proportions. Lower levels of γ-casein (P ≤ 0.05), β-casein, serum albumin as well as α-lactalbumin were observed in colostrum as compared to those in milk. Any relationship between lactation stage and β-casein content was observed. Serum albumin and α-lactalbumin content increased in subsequent milkings. The level of G class immunoglobulins decreased significantly and its highest level was noted in colostrum. Any significant differences between the 3rd and 6th lactation weeks were obtained. 相似文献
49.
Tree structural diversity is assessed by modelling stand diameter at breast height (DBH) distribution. The aim of this study
was to verify the suitability of a mixture of two- and three-component Weibull and gamma models for describing irregular and
multimodal DBH distributions. Investigations were carried out in natural Abies alba Mill. and Fagus sylvatica L. stands, representing the growing-up stage, in the Świętokrzyski National Park (Central Poland) and in the Pieniny National
Park (Southern Poland). Sample plots (0.25–0.5 ha in area) were selected from a database used for forest dynamics analysis.
The parameters of the mixture model were estimated using maximum likelihood estimation (MLE) and a combination of an expectation–maximisation
(EM) algorithm with a Newton-type (NT) method. The multistart method (MM) of choosing initial values was used. The DBH distributions
in mixed Abies–Fagus forests of complex structure were accurately approximated by two- and three-component mixture models. The root mean square
error (RMSE) values varied from 3.4515 to 7.6682 for the Weibull mixture and from 3.6457 to 7.1419 for the gamma mixture.
The results indicated that the mixture Weibull and gamma models were, in general, equally suitable for modelling irregular
and multimodal DBH distributions. Finite mixture models may be used to characterise tree structural diversity, especially
in uneven-aged stands of complex structure. 相似文献
50.
David Gunnarsson Gunnar Selstam Yvonne Ridderstr?le Lena Holm Elisabeth Ekstedt Andrzej Madej 《Acta veterinaria Scandinavica》2009,51(1):51