Effect of phosphorus concentration of the nutrient solution on the volatile constituents of leaves and bracts of Origanum dictamnus

The chemical composition of the essential oils obtained from the leaves and bracts of hydroponically cultivated Origanum dictamnus were analyzed by GC-MS techniques. Three different concentrations of phosphorus (5, 30, and 60 mg/L) in the nutrient solution were used for the cultivation, using the nutrient film technique (NFT). A total of 46 different compounds were identified and significant differences (qualitative and quantitative) were observed between the samples. Carvacrol and p-cymene were identified as the main compounds in all samples analyzed, whereas thymoquinone was found in higher percentage in the leaves than in bracts. The essential oils were tested for their antibacterial activity against Gram-positive and Gram-negative bacteria. The oils obtained from the bracts were found to be more active. The results obtained from GC-MS analyses were submitted to chemometric analysis.     

3D morphometric study of domestic fowl glomerulus—A scanning electron microscope study of vascular corrosion casts

Microvascularization of domestic fowl kidneys was studied using scanning electron microscopy (SEM) of vascular corrosion casts (VCCs). Two types of nephrons, mammalian-type (MT) and reptilian-type (RT) nephrons and their glomerular structure were analysed quantitatively by 3D morphometry. A significant difference in shape and size between the MT and RT glomeruli was found. The mean diameter of the RT glomeruli was about 56 µm, while that of MT glomeruli was significantly larger, namely about 80 µm. The afferent arterioles in mammalian-type glomeruli usually bifurcated into two lobular branches and formed a complex glomerular capillary network with numerous loops. Reptilian-type glomeruli consisted of a single capillary forming few loops and leaving the glomerulus as efferent arteriole. Diameters of afferent and efferent arteriolar replicas were similar in all three kidney divisions of MT and RT nephrons. The absence of the interconnecting branches between the MT nephron capillaries at the gross inspection suggests that the mammalian-type nephron glomeruli, although more complex than the reptilian type, are not equivalent to those in mammalian kidneys.     

Anatomical variations of the thoracic duct in the dog

Anatomical variations can be frequently found in the lymphatic system, which is also true for the shape and course of the thoracic duct (ductus thoracicus), the biggest lymph vessel in the body. From 2012 to 2019, the thoracic duct was successfully dissected in 43 dog carcasses that were used in the anatomy course at the Faculty of Veterinary Medicine, University of Zagreb. The thoracic duct originated from the cranial border of the cisterna chyli as one lymph vessel in 36 dogs (83.7%), as two vessels in six dogs (14%) and as three vessels in one dog (2.3%). We divided the observed thoracic duct variations into six groups according to their anatomical similarities. Considering the specific embryonic development, we can conclude that all observed variations are the result of minor deviations from the standard ontogenesis. However, the importance of thoracic duct variations is significant in surgical procedures done in the thoracic cavity to prevent or cure the chylothorax. Since this research showed variations in 39 out of 43 dogs (90.7%) throughout the whole course of the thoracic duct, great care must be taken while performing the ligation or embolization of the thoracic duct.     

Thermodynamics and structural features of the yeast Saccharomyces cerevisiae external invertase isoforms in guanidinium-chloride solutions

Recently, four external invertase isoforms (EINV1, EINV2, EINV3, and EINV4) have been isolated from S. cerevisiae. However, there is nothing known about their structural features and thermodynamics of unfolding. Since this information is essential for understanding their functioning at the molecular level as well as applicable in the food industry, we investigated guanidinium-chloride induced structural changes of the isoforms by CD and fluorescence spectroscopy. The resulting unfolding curves measured for each isoform at different temperatures were described simultaneously by a reversible two-state model to obtain the corresponding thermodynamic parameters. Here, we show that they are different for different isoforms and demonstrate that they correlate with the surface charge density of the native isoforms which follows the order EINV1 < EINV2 < EINV3 < EINV4. It appears that at physiological temperatures the thermodynamic stability of the isoforms follows the same order, while above 55 °C, the order is the opposite EINV1 > EINV2 > EINV3 ≈ EINV4. This suggests that increasing the efficiency of the food industry processes involving invertase would require the application of EINV3 and/or EINV4 at physiological temperatures and EINV1 at elevated temperatures.     

Co-oximetry in clinically healthy dogs and effects of time of post sampling on measurements

Objectives : Co‐oximetry is a complex and valuable laboratory method that measures haemoglobin species and oxygenation status by multi‐wavelength spectrophotometry. The purpose of this study was to establish reference intervals for clinically healthy dogs and to determine the effect of time of analyses and sex of animals on the accuracy of results. Methods : Blood was collected from 27 healthy adult dogs of various breeds and sex. Co‐oximetry was performed on a CCX co‐oximeter that measures eight haemoglobin and oxygen transport related parameters: carboxyhaemoglobin (COHb), deoxyhaemoglobin (HHb), oxyhaemoglobin (O₂Hb), methaemoglobin (MetHb), total haemoglobin (tHb), oxygen saturation (SO₂%), oxygen content (O₂Ct) and oxygen capacity (O₂Cap). Results : Results obtained after 2 and 4 hours were not significantly different from those obtained immediately after sampling. But after 48 hours, the results for total haemoglobin, oxygen saturation, oxyhaemoglobin, oxygen content and oxygen capacity were significantly lower, and carboxyhaemoglobin and deoxyhaemoglobin values were significantly higher than determination immediately after sampling. Gender had no significant impact on co‐oximetry values. Clinical Significance : Co‐oximetry offers several advantages compared with other methods, including ease of use, increased accuracy and greater differentiation among haemoglobin species.     

Influence of P-glycoprotein inhibition on secretion of ivermectin and doramectin by milk in lactating sheep

The aim of to the present study was to evaluate the effects of verapamil (VER) on plasma pharmacokinetics of ivermectin (IVM) and doramectin (DOR) in lactating Istrian Pramenka dairy sheep and to investigate the role of P-glycoprotein (P-gp) in transport of avermectins into milk. Pharmacokinetics of IVM and DOR following subcutaneous administration of 0.2mg/kg b.w. was evaluated in four groups of sheep. They were administered either IVM or DOR alone or in combination with verapamil (VER) at a dose of 3.0mg/kg b.w., 3 times at 12h intervals. Blood plasma and milk samples were collected at defined time intervals over 30 days post-treatment to determine IVM and DOR concentration levels. Pharmacokinetic parameters in sheep injected with IVM or DOR alone corresponded to previously published values. Comparison between sheep injected with IVM only, and sheep injected with IVM in combination with VER (IVM+VER) showed significant difference in pharmacokinetic parameters in blood plasma. Area under the concentration-time curve (AUC) truncated at 2 days (AUC(2)) was 15 and 28 μg day/L for group IVM and IVM+VER, respectively. With co-administration of VER, apparent plasma clearance (Cl/F) and mean residence time (MRT) of IVM decreased from 135 to 116 L/day and from 5.8 to 3.8 days, respectively. Similar trends were observed for DOR (AUC(2) 48 vs. 68 μg day/L, Cl/F 61 vs. 46 L/day, and MRT 5.6 vs. 4.4 days for groups DOR and DOR+VER, respectively). This study confirms that co-administration of VER has a significant effect on pharmacokinetic parameters of subcutaneously administered IVM in blood plasma. The influence on DOR pharmacokinetics is much weaker. This could be either due to the difference in lipophilicity or the difference in affinity towards P-gp as a result of structural differences. No significant influence of VER on AUC ratio of IVM and DOR between milk and plasma was observed suggesting that P-gp does not govern transport of avermectins into milk.     

Antimicrobial susceptibility of Clostridium perfringens isolates of bovine, chicken, porcine, and turkey origin from Ontario

Antimicrobial susceptibilities and toxin types were determined for 275 Clostridium perfringens isolates collected in Ontario in the spring of 2005. Minimal inhibitory concentrations (MICs) of C. perfringens isolates for 12 antimicrobials used in therapy, prophylaxis, and/or growth promotion of cattle (n = 40), swine (n = 75), turkeys (n = 50), and chickens (n = 100) were determined using the microbroth dilution method. Statistical analyses and MIC distributions showed reduced susceptibility to bacitracin, clindamycin, erythromycin, florfenicol, and tetracycline for some isolates. Reduced susceptibility to bacitracin was identified in chicken (64%) and turkey (60%) isolates. Swine isolates had predominantly reduced susceptibility to clindamycin (28%) and erythromycin (31%), whereas bovine isolates had reduced susceptibility to clindamycin (10%) and florfenicol (10%). Reduced susceptibility to tetracycline was spread across all species. No clear reduced susceptibility, but elevated MIC(50) for virginiamycin was found in chicken isolates in comparison with isolates from other species. Toxin typing revealed that C. perfringens type A is the dominant toxin type isolated in this study across all 4 host species.     

Effects of two probiotic additives containing Bacillus spores on carcass characteristics, blood lipids and cecal volatile fatty acids in meat type chickens

The objective of this study was to evaluate effects of two commercially available probiotic additives, containing Bacillus spores, on carcass and meat characteristics, serum lipids and concentration of cecal volatile fatty acids of meat type chickens. Birds were fed regular corn-soy meal based feed (control), supplemented with additive A, containing 1.6 × 10(6) spores per gram of feed of Bacillus subtilis and Bacillus licheniformis (group A) or additive B, containing the same concentration of Bacillus cereus var. toyoi spores (group B). One hundred and twenty birds (20 per replicate) were slaughtered at the age of 55 days. Results showed that birds in group B had higher (p < 0.05) final body weight compared to birds from group A and higher carcass weights and yield percentages compared with control. Breasts and whole legs were also heavier in group B, compared to control, but not the yield. Group A had higher yield of wings and lower abdominal fat weight compared to group B (p< 0.05), but not compared with control. Total cholesterol was not affected by the dietary treatment, on contrary both probiotics elevated the LDL (p < 0.05) and lowered HDL cholesterol, thus unfavourably changed animal's blood serum cholesterol profile. Both probiotics influenced the cecal fermentation, which was observed as decrease in cecal concentrations of propionic, butyric, n-butyric and n-valeric acids, but the differences compared to control group were statistically significant for group A only. It was established that probiotic additive B was more effective regarding carcass and meat part weights than additive A, however the animals from group B also had more abdominal fat and their meat had significantly higher conductivity than control group, which is not considered as beneficial.     

Hepatoprotective effect of curcumin in lipopolysaccharide/-galactosamine model of liver injury in rats: relationship to HO-1/CO antioxidant system

This work studied a relationship between HO-1/CO system and lipid peroxidation with consequent effects on liver functions and NOS-2. We focused on curcumin pretreatment in rat toxic model of d-galactosamine and lipopolysaccharide. Hepatocyte viability, lipid peroxidation, antioxidant status, ALT and AST were evaluated. HO-1 and NOS-2 expressions and respective enzyme activity were determined. Curcumin caused decreases in ALT and AST levels as well as in lipid peroxidation. Furthermore, curcumin pretreatment increased liver HO-1 (2.4-fold, p = 0.001), but reduced NOS-2 (4.1-fold, p = 0.01) expressions. In conclusion, the tuning of CO/NO pathways is important in shedding light on curcumin's cytoprotective effects in this model.     

Speciation of 90Sr and other metal cations in artificially contaminated soils: the influence of bone sorbent addition

Purpose

The influence of bone sorbent addition onto distribution of ⁹⁰Sr in artificially contaminated soil was preliminary studied to assess the possibility of biogenic apatite utilization for reduction of ⁹⁰Sr mobility and availability. Simultaneously, the disruption of soil micro- (Cd, Zn, Co, Cu, Cr, and Ni,) and macroelements (Al, Fe, Mn, K, Mg, and Ca) upon Sr contamination and sorbent addition was monitored.

Materials and methods

The model soil was contaminated by inactive Sr, in the form of Sr(NO₃)₂ solution. As a soil additive, sorbent obtained by annealing bovine bones at 400 °C (B400) was applied. Both the uncontaminated and Sr-contaminated soils were mixed with 1, 3, 5, and 10 % of sorbent, suspended in distilled water (initial pH?5; solid/solution ratio, 1:2), and equilibrated for 15 days on a rotary shaker. Solid residues were subjected to modified Tessier five-step sequential extraction analysis, and the amounts of chosen metals in each fraction were determined by inductively coupled plasma–optical emission spectroscopy.

Results and discussion

In the original soil, Sr was mainly found in exchangeable (61 %) and carbonate phase (16 %), whereas after contamination, the content of Sr in exchangeable phase raised to 94 %. With the addition of B400, the decrease in Sr amounts in exchangeable fraction was detected, whereas increase occurred mainly in operationally defined carbonate phase and in the residual. High level of Sr contamination caused the increase in Zn, Ni, Co, Cu, Cd, and Mn and decrease in Ca content in exchangeable phase. Sorbent addition resulted in a migration of these cations to less soluble fractions. This effect was observed even for major soil elements such as Fe, Al, and Mn, regardless of the excessive amounts of Sr in the soil.

Conclusions

Mixing the soil with B400 resulted in reduced Sr mobility and bioavailability. B400 acted as a stabilizing agent for heavy metals, as well. Apatite distinguished selectivity towards heavy metals may interfere with the Sr immobilization and disrupt original cation distribution. Further studies should include more realistic (lower) Sr concentrations in the soil, different soil types, pH, and longer incubation times.