Relating genetic variation of ecologically important tree traits to associated organisms in full-sib aspen families

Knowledge on phenological, morphometric, and phytochemical variation of local progenies of European aspen (Populus tremula, L.) is limited. The goal of this study was to characterize variation in growth and ecologically important leaf properties in aspen full-sib families in relation to interacting organisms (mycorrhiza, endophytes, and insects) and to determine whether these interactions were affected by soil application of a systemic fungicide. In local progenies, within-family variation of neutral molecular genetic markers (nuclear microsatellites) was higher than between families. Significant variation in growth, production of phenolic defensive compounds and other phytochemical leaf traits was found between families. Phenolic compounds showed clear negative correlation with generalist herbivores, but did not result in negative trade-off with biomass production. Differences in mycorrhizal colonization were not found among full-sib families and application of a systemic fungicide suppressed neither mycorrhizal colonization nor infestation with insects. However, a strong suppression of endophytes occurred, whose long-term consequences may require attention when fungicides are used in agroforestry plantations.     

The influence of gel strength on aroma release from pectin gels in a model mouth and in vivo, monitored with proton-transfer-reaction mass spectrometry

The course of events from taking a food into the mouth to the perception of the food's flavor involves many steps, from dilution with saliva, mastication, and transportation of the compounds to the olfactory epithelium to transformation into signals that go to the brain. In addition, there are also the effects of the food's structure and properties. In this study, a proton-transfer-reaction mass spectrometer (PTR-MS) was used to investigate how four pectin-containing systems with different structures and strengths affected the release of aroma compounds in a model mouth and in the nose of an assessor. Both the model mouth and the in-nose measurements showed that the strength and structure of pectin-containing systems are important with regard to the quantity of aroma compounds that are released. Mastication and saliva were also shown to have a large influence on how much of the aroma compound is released from the mouth to the nose.     

Oxygen deficiency in barley (Hordeum vulgare) grain during malting

The steep water is generally aerated in industrial barley malting. However, it is questionable whether oxygen actually reaches the embryo, which remains entrapped under the husk, testa, and pericarp until chitting occurs. The aim of our study was to investigate whether barley embryos experience oxygen deficiency during steeping, and whether various steeping conditions affect the oxygen deficiency. Alcohol dehydrogenase Adh2 was induced in all steeping conditions studied. Therefore, oxygen deficiency occurred regardless of the steeping conditions. However, steeping conditions affected the rate of recovery from oxygen deficiency, germination rate, and onset of alpha-amylase production. When barley was subjected to oxygen deficiency by applying N(2) gas during steeping, the timing of the treatment determined its effects. The importance of aeration increased as the process proceeded. Oxygen deprivation at the beginning of the process had little effect on malt quality. Therefore, the timing of aeration is important in the optimization of germination during the steeping stage of malting.     

Postprandial glycemia, insulinemia, and satiety responses in healthy subjects after whole grain rye bread made from different rye varieties. 1

Rye products typically induce low insulin responses and appear to facilitate glucose regulation. The objective of this study was to investigate differences in postprandial glucose, insulin, and satiety responses between breads made from five rye varieties. Breads made from whole grain rye (Amilo, Rekrut, Dankowski Zlote, Nikita, and Haute Loire Pop) or a white wheat bread (WWB) were tested in a randomized cross-over design in 14 healthy subjects (50 g available starch). Metabolic responses were also related to the composition of dietary fiber and bioactive compounds in the breads and to the rate of in vitro starch hydrolysis. The Amilo and Rekrut rye breads induced significantly lower insulin indices (II) than WWB. Low early postprandial glucose and insulin responses (tAUC 0-60 min) were related to higher amounts of caffeic, ferulic, sinapic, and vanillic acids in the rye breads, indicating that the phenolic acids in rye may influence glycemic regulation. All rye breads induced significantly higher subjective feelings of fullness compared to WWB. A low II was related to a higher feeling of fullness and a lower desire to eat in the late postprandial phase (180 min). The data indicate that some rye varieties may be more insulin-saving than others, possibly due to differences in dietary fiber, rate of starch hydrolysis, and bioactive components such as phenolic acids.     

The density dilemma: limitations on juvenile production in threatened salmon populations

Density‐dependent processes have repeatedly been shown to have a central role in salmonid population dynamics, but are often assumed to be negligible for populations at low abundances relative to historical records. Density dependence has been observed in overall spring/summer Snake River Chinook salmon Oncorhynchus tshawytscha production, but it is not clear how patterns observed at the aggregate level relate to individual populations within the basin. We used a Bayesian hierarchical modelling approach to explore the degree of density dependence in juvenile production for nine Idaho populations. Our results indicate that density dependence is ubiquitous, although its strength varies between populations. We also investigated the processes driving the population‐level pattern and found density‐dependent growth and mortality present for both common life‐history strategies, but no evidence of density‐dependent movement. Overwinter mortality, spatial clustering of redds and limited resource availability were identified as potentially important limiting factors contributing to density dependence. The ubiquity of density dependence for these threatened populations is alarming as stability at present low abundance levels suggests recovery may be difficult without major changes. We conclude that density dependence at the population level is common and must be considered in demographic analysis and management.     

Mixing methods – assessment of potential benefits for natural resources planning

Multi-objective forest planning is a multi-methodological endeavor whose success largely depends on how well the combined use of different methods contributes to the goals of the planning. This review assessed the benefits of mixing methods in natural resources planning. A sample of 30 peer-reviewed research articles was analyzed using an evaluation framework, designed based on democracy and planning theories, and participatory planning literature, including four dimensions: transparency, flexibility, consensus building, and operability. According to analyses, mixing different types (i.e. qualitative and quantitative) of methods generally yields greater benefits than the combination of similar methods. The subsample of 12 planning cases that utilized simulation-optimization software (SOS) appeared operable and moderately transparent, whereas flexibility and consensus building were often lacking. In comparison to the wide scholarly discussion on multi-methodology and mixing methods, it was observed that successful mixing examples in natural resource planning are still scarce and there are weaknesses in bridging the methods together. There is an evident need to pursue and to better communicate the benefits of mixing. Some good mixing examples utilizing SOS provided evidence that forest planning processes would make an excellent venue for studying the benefits and caveats of using mixed methods.     

Comparative growth performance of pigs immunised with a gonadotrophin releasing factor vaccine with surgically castrated pigs and entire boars raised under conventionally managed conditions

The objective of this study was to determine the effect of using a gonadotrophin releasing factor (GnRF) vaccine on growth performance of male pigs. Vaccinated pigs were compared with surgically castrated pigs and entire males under conventionally managed farm conditions. Male pigs were randomly assigned to three treatment groups: pigs surgically castrated during the first week of life (group "C", n=274), pigs immunised twice during the fattening period with a GnRF vaccine, the first when 13-14 weeks of age and the second when 20-21 weeks of age (group "V" n=280) and entire males (group "E", n=56). Average daily weight gain (ADG) was measured during the study. Additionally, feed conversion ratio (FCR) as defined by feed intake/weight gain and feed consumption was assessed during the fattening period. No difference in the ADG during the fattening period could be determined between "C" and "V". From the start of the study until slaughter at study day 160/173 the ADG in group "E" was lower (625 g/day; P) than in group "C" (681 g/day; P < 0.001) and group "V" (675 g/day; P < 0.01). The FCR during the fattening period until study day 160, three days before the first batch of pigs were slaughtered at 24-25 weeks of age, was higher in group"C" (2.72 kg feed intake/kg weight gain) compared with group "V" (2.44 kg feed intake/kg weight gain; P < 0.001) and group "E" (2.44 kg feed intake/kg weight gain; P <0.01). Pigs in group "V" performed similarly to those in group "E" until the second vaccination (day 135) after which time they showed a substantial increase in feed intake and ADG, while retaining an FCR advantage over group C.     

Fatal epizootic equine herpesvirus 1 infections in new and unnatural hosts

In a zoological collection, four black bears (Ursus americanus) died from neurological disease within six months. Independently in a geographically different zoo, two Thomson's gazelles (Eudorcas thomsoni) and 18 guinea pigs (Cavia porcellus f. dom.) suffered from neurological disorders. In addition, guinea pigs showed abortions and stillbirths. All affected animals displayed a non suppurative meningoencephalitis with intranuclear inclusion bodies. Immunohistology demonstrated equine herpes virus antigen and ultrastructurally herpes viral particles were detected. Virus isolation and molecular analysis identified neurotropic equine herpesvirus (EHV) 1 strains in both epizootics. There is serological evidence of a possible virus transmission from other equids to the affected animals. Cross-species transmission of EHV-1 should be considered in the management of captive wild equids and ungulates, particularly with respect to fatal disease in irreplaceable species.