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In a field study during two growing seasons in northern Sweden, we assessed meadow fescue (Festuca pratensis Huds.) with and without Neotyphodium uncinatum to determine whether the endophyte affects plant performance regarding tiller and biomass production. In addition, we measured loline alkaloids produced in infected grasses. Approximately 1000 plants grew at two different levels of nitrogen fertilization: the normal amount applied in this region and one-half that amount. Increasing the amount of nitrogen increased the total number of tillers on the plants. Endophyte-infected plants produced more tillers per plant than plants without the endophyte; there was, however, no significant difference in proportion of reproductive tillers, winter survival, or total biomass production between endophyte-infected and noninfected plants. Infected plants produced loline alkaloids in different quantities without indication of being influenced by different nitrogen fertilization levels. Key words: endophyte, forage, nitrogen fertilization. Nous avons evalue la fetuque des pres (Festuca pratensis Huds.) dans une etude sur le terrain realisee au cours de deux saisons de croissance dans le nord de la Suede, en presence ou en absence de Neotyphodium uncinatum, afin de determiner si 'endophyte affecte la performance de la plante sur le plan de la production de talles et de biomasse. Nous avons de plus mesure es alcaloides loline produits par l'herbe infectee. Pres d'un millier de plantes ont pousse sous deux conditions de fertilisation a 'azote : la quantite normale appliquee dans cette region et la moitie de cette quantite. L'augmentation de la quantite d'azote ccroissait le nombre total de talles sur les plantes. Les plantes infectes par l'endophyte produisaient davantage de talles par lante que les plantes sans endophyte; cette difference n'etait toutefois pas significative en proportion des talles reproductives, e la survie a l'hiver ou de la biomasse totale entre les plantes infectes et non infectes. Les plantes infectes produisaient des lcaloides loline en quantites differentes, sans indication que cela ait ete influence par les differents niveaux de fertilisation a 'azote. [Traduit par la Redaction] Mots-cles: endophyte, forage, fertilisation a l'azote., Introduction Meadow fescue (Festuca pratensis Huds.) is a perennial pooid grass that grows widely in Northern Europe and parts of Asia. In the Nordic and Baltic countries, it is an [...]

Whey protein concentrate (WPC) and hydrolysate (WPH) are protein ingredients used in sports, medical and pediatric formulations. Concentration and hydrolysis methods vary for whey sourced from cheese and casein co-products. The purpose of this research was to investigate the influence of whey processing methods on in vitro gastrointestinal (GI) health indicators for colonic motility, epithelial barrier integrity and immune modulation. WPCs from casein or cheese processing and WPH (11% or 19% degree of hydrolysis, DH) were compared for their effects on motility in a 1 cm section of isolated rat distal colon in an oxygenated tissue bath. Results showed that WPC decreased motility irrespective of whether it was a by-product of lactic acid or mineral acid casein production, or from cheese production. This indicated that regardless of the preparation methodology, the whey protein contained components that modulate aspects of motility within the distal colon. WPH (11% DH) increased contractile frequency by 27% in a delayed manner and WPH (19% DH) had an immediate effect on contractile properties, increasing tension by 65% and frequency by 131%. Increased motility was associated with increased hydrolysis that may be attributed to the abundance of bioactive peptides. Increased frequency of contractions by WPH (19% DH) was inhibited (by 44%) by naloxone, implicating a potential involvement of opioid receptors in modulation of motility. Trans-epithelial electrical resistance and cytokine expression assays revealed that the WPC proteins studied did not alter intestinal barrier integrity or elicit any discernible immune response. [ABSTRACT FROM AUTHOR]

Birds and other forms of wildlife are a major issue for airport authorities worldwide, as they can create hazards to operating aircraft. Wildlife "strikes," the majority caused by birds, can cause damage to operating aircraft and in severe cases lead to a loss of human life. Many airfields contain large areas of ground cover herbage alongside their runways that consist of mixtures of grasses, legumes, and weeds that can harbor many invertebrates. Many airfields use insecticides to control insect populations; however, mounting pressure from regional councils and water boards aim to reduce this practice due to ground water runoff and contamination concerns. Avanex Unique Endophyte Technology, a product specifically developed to reduce the attractiveness of airports and surrounding areas to birds, is based on a novel association between a selected strain of Epichloë endophyte and a turf-type tall fescue cultivar. This grass-endophyte association acts through a direct mechanism whereby a negative response in birds is created through taste aversion and postingestion feedback as well as an indirect mechanism by deterring many invertebrates, a food source of many bird species. [ABSTRACT FROM AUTHOR]