Characterization of the most odor-active volatiles of orange wine made from a Turkish cv. Kozan (Citrus sinensis L. Osbeck)

The aroma-active compounds of cv. Turkish Kozan orange wine were analyzed by sensory and instrumental analyses. Liquid-liquid extraction with dichloromethane was used for extraction of volatile components. According to sensory analysis, the aromatic extract obtained by liquid-liquid extraction was representative of orange wine odor. A total of 63 compounds were identified and quantified in orange wine. The results of the gas chromatography-olfactometry analysis showed that 35 odorous compounds were detected by the panelists. Of these, 28 aroma-active compounds were identified. Alcohols followed by terpenes and esters were the most abundant aroma-active compounds of the orange wine. Among these compounds, ethyl butanoate (fruity sweet), 3-methyl-1-pentanol (roasty), linalool (floral citrusy), gamma-butyrolactone (cheesy burnt sugar), 3-(methylthio)-propanol (boiled potato, rubber), geraniol (floral citrusy), and 2-phenylethanol (floral rose) were the most important contributors to the aroma of the orange wine because they were perceived by all eight panelists.     

The Effect of Understocking Density of Channel Catfish Stockers in Multiple-Batch Production

A multiple-batch study was conducted using stocker catfish (0.09 kg/fish) and carryover fish (0.39 kg/fish) to look at the effects of different stocker densities on fish production. Twelve 0.1-ha ponds were stocked with 7,400; 11,120; or 14,825 stockers/ha, and equal weights of carryover fish (2,268 kg/ha). Fish were fed once daily to apparent satiation with a 32% protein floating feed and aerated with a single 0.37-kW electric paddlewheel aerator. No significant differences were detected for gross, net, and net daily yields, growth (g/d), or survival. Sub-marketable yield (<0.57 kg) increased as stocking density increased. However, marketable yields (≥0.57 kg) were not affected by density. Carryover fish in high-density ponds had a significantly lower (P < 0.05) mean weight at harvest, but mean stocker weight was not different across densities. Economic analysis found breakeven prices increased and net returns decreased with increased stocking density when sub-marketable fish were not considered as revenue. The study indicated the possibility that stockers compete with large carryover fish, particularly at higher densities.     

Pancreatic Polypeptide and Insulin-Secreting Tumor in a Dog With Duodenal Ulcers and Hypertrophic Gastritis

A 7-year-old spayed female Cocker Spaniel was hospitalized with a history of chronic vomiting, anorexia, and weight loss. Laboratory abnormalities included leukocytosis, metabolic alkalosis, hypoglycemia, hypoproteinemia, and hyperinsulinemia. Gastroscopy and ultrasonography revealed multiple gastric masses and a possible pancreatic mass, respectively. Examination of tissues obtained at necropsy showed a pancreatic adenocarcinoma with hepatic metastasis, gastric hypertrophy, and multiple duodenal ulcers. Immunocytochemical staining of the neoplasia was positive for pancreatic polypeptide (PP) and insulin and negative for gastrin, calcitonin, adrenocorticotropic hormone (ACTH), serotonin, L-enkephalin, chromagranin, glucagon, and somatostatin. Subsequent serum gastrin and PP assays showed a fasting hypergastrinemia with a normal response of gastrin to provocative testing and extremely increased PP values. The high PP values may have resulted in the vomiting and gastrointestinal ulceration. A PP-secreting tumor has not previously been reported in the dog.     

Glycosylated Hemoglobin Concentration for Assessment of Glycemic Control in Diabetic Cats

Blood glycosylated hemoglobin (GHb) concentration was quantified in 84 healthy cats, 9 cats with stress-induced hyperglycemia, 37 cats with newly diagnosed diabetes mellitus, and 122 diabetic cats treated with insulin or glipizide. Diabetic control was classified as good or poor in insulin-treated or glipizide-treated cats based on review of history, physical examination findings, changes in body weight, and measurement of blood glucose concentrations. Blood GHb concentration was determined using an affinity chromatography assay. Mean blood GHb concentration was similar for healthy normoglycemic cats and cats with transient, stress-induced hyperglycemia, but was significantly (P < .001) higher in untreated diabetic cats when compared with healthy normoglycemic cats. Mean blood GHb concentration was significantly (P < .001) higher in 84 cats with poorly controlled diabetes mellitus when compared with 38 cats in which the disease was well controlled. Mean blood GHb concentration decreased significantly (P < .01) in 6 cats with untreated diabetes mellitus after insulin and dietary treatment. A similar significant (P < .01) decrease in mean blood GHb concentration occurred in 7 cats with poorly controlled diabetes mellitus after diabetic control was improved by an increase in insulin dosage from 1.1 ± 0.9 to 1.4 ± 0.6 U/kg/ 24 h and by feeding a diet containing increased fiber content and in 6 cats with transient diabetes mellitus 8.2 ± 0.6 weeks after discontinuing insulin treatment. There was a significant (P< .01) stress-induced increase in mean fasting blood glucose concentration and mean blood glucose concentration for 12 hours after administration of insulin or glipizide but no change in mean blood GHb concentration in 5 docile diabetic cats 12.2 ± 0.4 weeks after the cats became fractious as a result of frequent hospitalizations and blood samplings. Results of this study suggest that evaluation of blood GHb concentration may be a clinically useful tool for monitoring glycemic control of diabetes in cats.     

Pseudomonads as a factor in the growth of winter wheat (Triticum aestivum L.)

Pseudomonads were isolated from the roots of winter wheat plants. Plants produced from direct-drilling of seeds into plots where crop residues had been burnt were larger and appeared healthier than those from plots where crop residues remained. Tests showed that roots from the plants direct-drilled into the plots where crop residues had been burnt were colonized by fewer pseudomonads which could inhibit plant growth than those from plants produced from plots where crop residues remained. The tests were performed by inoculating wheat seedlings with individual bacterial isolates and measuring root growth. When several wheat cultivars were bioassayed against each of two of the inhibitory pseudomonads, they differed greatly in susceptibility to the adverse effects of the bacteria.     

Effects of single-tree and group selection harvesting on the diversity and abundance of spring forest herbs in deciduous forests in southwestern Ontario

Selection harvesting, by mimicking natural disturbance regimes of eastern deciduous hardwood forests, has been applied as a sustainable management practice that combines wood production with biodiversity conservation. However, the effects of this technique on understory herbs are unclear, particularly for spring ephemerals which have been suggested as sensitive to disturbance. Here, we experimentally assess the immediate effects of single-tree and group selection harvesting on spring ephemeral richness, diversity and abundance in deciduous forests of southwestern Ontario, Canada. Spring herbs were quantified in 4 m² plots before and one growing season after harvesting and compared to similar uncut, reference stands. The percent of species lost was significantly higher in reference than harvested plots. Mean species richness significantly increased after harvesting, predominately due to an increase in spring–summer species. Increases in the diversity of early spring flowering species were significantly greater in the group selection plots than reference plots. At the community level, no species appeared to be vulnerable to harvesting, and ordination analysis indicated that post-harvest communities were primarily determined by pre-harvest community composition. Furthermore, no species declined in abundance in response to harvesting, and overall percent cover increased proportionately more in single-tree selection plots than in group selection or reference plots. While harvesting appears to have negligible effects on spring ephemerals immediately following harvest, we recommend additional studies over longer time frames to assess possible successional effects and to discriminate treatment induced changes from naturally high yearly variation in species composition.     

Research needs for restoring seasonal tropical forests in Thailand: accelerated natural regeneration

Accelerated natural regeneration (ANR) is a relatively cheap method of reforestation, which encourages natural establishment of indigenous trees and shrubs. It requires a low input of labour, but a high input of ecological information. In this paper, the knowledge required to predict and manipulate the natural regeneration of seasonal tropical forest is reviewed and areas in need of further research are identified. Regeneration will be influenced by five groups of potentially limiting factors; site resources (soil and microclimate); competition with weeds; site disturbance; occurrence of established woody plants or their propagules; seed dispersal by wild animals and birds. This paper considers each of these, their interactions with seasons, and each other. Collation of existing information on these topics, combined with the suggested further research, should facilitate the creation of tools that will enable practitioners to judge the regeneration potential of sites and to select the most appropriate ANR techniques.