Fast and local assessment of stilbene content in grapevine leaf by in vivo fluorometry

Stilbenes are grapevine phytoalexins. These highly fluorescent molecules are generally analyzed by HPLC. This technique allows accurate assay of different stilbenes, but it is destructive, time-consuming, and neglects their spatial distribution. This is why we have tested a new method based on in vivo fluorescence using commercial spectrofluorometers that allowed fast and local assessment of stilbene content in grapevine leaves. Stilbene synthesis in grapevine Vitis vinifera var. Muscat Ottonel leaves was induced by Plasmopara viticola inoculation or UV-C irradiation. Fluorescence was measured both from the abaxial and adaxial sides of leaves, then stilbene content was analyzed by HPLC. It varied from 0 in control leaves to 15 mg g-1 dry weight in UV-treated leaves. Highly significant regressions were found between HPLC stilbene content and the corresponding leaf UV-induced blue fluorescence. Thus, in vivo fluorescence is a good tool for a rapid study of stilbenes synthesis in grapevine leaves that can potentially be extended to other fluorescent molecules.     

Results of the long-term field experiment IOSDV Rakičan at the beginning of the 21st century

This article presents the results of a long-term field experiment at Raki?an (Eastern Slovenia). Between 1993 and 2010, the temperature increased at a rate of 0.0288°C a^?1, while average annual precipitation did not change, but showed great variation from year to year. In years with a higher average annual temperature, higher crop yields were achieved. Higher amounts of precipitation had a positive impact on yield at higher mineral nitrogen (N) rates, but a negative impact on yield in treatments with no mineral N. In systems with farmyard manure (FYM) and straw incorporation, maize yields increased in accordance with the increase in mineral N. Winter wheat yields increased with increasing mineral N to the N1 mineral N application rate with FYM application, and N2 with straw incorporation. Yields of winter barley increased in accordance with increasing mineral N until the highest N application rate (N3) with FYM application, and until N2 with straw incorporation. With regard to environmental compliance requirements for N and C balances and the crop yields, in FYM the most appropriate rate of fertilization is N1, and with straw incorporation the most appropriate rate is N1 to N2.     

Morphological and physiological evaluation of common carp (Cyprinus carpio L., 1758) fed extruded compound feeds containing different fat levels

The study was carried out to examine morphological and physiological effects of different levels of fat in compound extruded feed for carp. A 90 days experiment was performed in tanks with water flow 0.34 L min^?1, stocked each with 29 specimens of carp, average weight 15.4 ± 4.2 g. The fish was fed 3 diets containing 38 % protein and 8, 12 or 16 % of fat (feed L8, L12, and L16, respectively). Body weight gain, specific growth rate, food conversion ratio, feed efficiency ratio, condition factor, liver and intestine histology and morphometry and some blood biochemical parameters were analysed. At the end of the experiment, a difference was established between the fish fed L8 feed compared to carp fed L12 and L16 feed for all growth parameters. For several other parameters, nuclear area of hepatocytes, nuclear/cytoplasm ratio, enterocytes height and intestinal folds’ length, a difference between carp fed feed L8 compared to feed L16 was found. The histological analysis revealed that normal structure of the liver and intestine prevailed, but changes were observed regardless of the diet type. In the hepatopancreas, more prominent changes were found around pancreatic tissue—particularly, increased number and size of adipocytes. Although blood biochemical parameters were within normal values, a difference between L8 and L16 diet-fed carp was found for plasma levels of triglycerides and total proteins. According to the results obtained in this study, the best results were achieved using a feed with 8 % fat.     

Hyperactivity and alopecia associated with ingestion of valproic acid in a cat

A 1-year-old castrated male cat was evaluated because of alopecia of approximately 4 to 5 months' duration as well as hyperactive behavior. It was later determined that the cat was ingesting valproic acid by eating food to which it had been added for daily administration to a child in the household who had cerebral palsy. The clinical signs slowly resolved after the source of valproic acid was removed. This emphasizes the sensitivity of cats to drugs that are commonly used in humans. It was not determined whether the clinical signs that developed in this cat were caused by an adverse reaction or from toxicosis as a result of prolonged hepatic elimination of valproic acid, which requires glucuronide metabolism for disposition. However, the cat recovered completely following removal of the drug and prevention of further exposure. This report emphasizes the importance of obtaining a careful and complete history from the owner regarding an animal and its environment. In the cat of this report, the owner had not considered the impact of the presence of the drug in the child's food.     

Teratogenic effects of the fungicide benomyl on posterior segmental regeneration in the earthworm,Eisenia fetida

Earthworms, Eisenia fetida, were treated by surface exposure to the fungicide benomyl at various stages of posterior segmental regeneration. Teratogenic effects of benomyl were observed when worms were treated 7–11 days after amputation (i.e. during the normal period of segmental replication), but not during days 1–5, 13–17, or 19–23. Teratogenic effects included a reduction in the number of regenerated segments, an increased frequency of segmental groove anomalies, and a variety of monstrosities. The effects of benomyl treatment on the number of regenerated segments and frequency of anomalies were dose-dependent within a narrow concentration range (approximately 0.2–5.0 mg litre^?1); at higher concentrations (e.g. 25 mg litre^?1) teratogenic effects were less frequent because the onset of segmental delineation was delayed until well after exposure. Non-invasive electrophysiological recordings from treated worms indicated that functional integrity of giant nerve fibre conduction pathways was established in all anomalously regenerated tail segments, except in a two-tailed monstrosity. The evidence supports the hypothesis that these teratogenic effects derive from an antimitotic mode of action of benomyl on segmental regeneration.     

Evidence of an acute phase response in dogs naturally infected with Babesia canis

The erythrocyte sedimentation rate (ESR), white blood cell count (WBC), haematocrit (HCT) and platelet number (PLT) were quantified and compared with the acute phase proteins (APPs) in dogs naturally infected with Babesia canis and healthy dogs. Both groups were treated with imidocarb dipropionate on the day of admission and both groups were monitored for all parameters on the admission day and on the first, second, third, fourth and seventh days in order to determine the presence of an acute phase reaction, to assess the diagnostic value of these markers in uncomplicated canine babesiosis and to evaluate the use of APPs in treatment monitoring. It was demonstrated that an acute phase response occurs in dogs naturally infected with Babesia canis, with significant increases in the concentration of major acute phase proteins. The serum concentration of C-reactive protein (CRP), serum amyloid A (SAA) and the erythrocyte sedimentation rate (ESR) decreased daily after treatment and approached reference range values by the eighth day. PLT and haematocrit (HCT) increased daily after treatment and approached reference range values by the fourth day. WBC and haptoglobin increased after treatment and then decreased from the third and fourth days, respectively, to the eighth day. The diagnostic sensitivity of CRP, SAA and PLT was significantly higher compared to haptoglobin, ESR, HCT and the WBC count. CRP and SAA were of clinical use in monitoring the response to antibabesial treatment.