Comparative changes in color features and pigment composition of red wines aged in oak and cherry wood casks

The color features and the evolution of both the monomeric and the derived pigments of red wines aged in oak and cherry 225 L barriques have been investigated during a four months period. For cherry wood, the utilization of 1000 L casks was tested as well. The use of cherry casks resulted in a faster evolution of pigments with a rapid decline of monomeric anthocyanins and a quick augmentation formation of derived and polymeric compounds. At the end of the aging, wines stored in oak and cherry barriques lost, respectively, about 20% and 80% of the initial pigment amount, while in the 1000 L cherry casks, the same compounds diminished by about 60%. Ethyl-bridged adducts and vitisins were the main class of derivatives formed, representing up to 25% of the total pigment amount in the cherry aged samples. Color density augmented in both the oak and cherry wood aged samples, but the latter had the highest values of this parameter. Because of the highly oxidative behavior of the cherry barriques, the use of larger casks (e.g., 1000 L) is proposed in the case of prolonged aging times.     

Mechanisms of resistance and susceptibility to experimental visceral leishmaniosis: BALB/c mouse versus syrian hamster model

ABSTRACT: Several animal models have been established to study visceral leishmaniosis (VL), a worldwide vector-borne disease affecting humans and domestic animals that constitutes a serious public health problem. BALB/c mice and Syrian hamsters are the most widely used experimental models. In this paper, we summarize the advantages and disadvantages of these two experimental models and discuss the results obtained using these models in different studies of VL. Studies using the BALB/c mouse model have underscored differences between the liver and spleen in the course of VL, indicating that pathological evaluation of the visceral organs is essential for understanding the immune mechanisms induced by Leishmania infantum infection. The main goal of this review is to collate the relevant literature on Leishmania pathogenesis into a sequence of events, providing a schematic view of the main components of adaptive and innate immunity in the liver and spleen after experimental infection with L. infantum or L. donovani. This review also presents several viewpoints and reflections about some controversial aspects of Leishmania research, including the choice of experimental model, route of administration, inoculum size and the relevance of pathology (intimately linked to parasite persistence): a thorough understanding of which is essential for future VL research and the successful development of efficient control strategies for Leishmania spp.     

Neuromuscular disorders in the cat: clinical approach to weakness

PRACTICAL RELEVANCE: Weakness is a relatively common clinical presentation in feline medicine and can be caused by primary neuromuscular disease or by diseases of other body systems affecting the neuromuscular system secondarily. Successful work-up relies on a thorough clinical and neurological examination, and logical problem solving, based on an understanding of the underlying neuroanatomical and pathophysiological mechanisms. CLINICAL CHALLENGES: Feline neuromuscular diseases can be a diagnostic challenge. On initial inspection, the presenting signs can mimic disorders of other body systems, particularly cardiovascular, pulmonary and orthopaedic disease, or may be confused with systemic illnesses. Additionally, because many different pathologies of the feline neuromuscular system converge to a similar clinical phenotype, further diagnostic steps such as electrodiagnostics, cerebrospinal fluid analysis, and muscle and nerve biopsies must be considered even after neuromuscular dysfunction has been identified. AUDIENCE: This review provides a framework for the clinical approach to the weak cat and gives a practical summary of neuromuscular diseases for the general practitioner and specialist alike. EVIDENCE BASE: Many diseases affecting the feline neuromuscular system have been well described in the veterinary literature, mostly based on retrospective case reports and series. The evidence base for the treatment of feline neuromuscular diseases remains very limited.     

Mentor pollen effect on the in-vivo germination of self-incompatible apple pollen

Investigations were carried out to ascertain to what extent “mentor pollen” can influence the performance of self pollen in apple styles. Self-incompatible ‘Starkrimson’ flowers on branches, placed at room temperature or in a growth chamber, were (1) self-pollinated, (2) cross-pollinated with compatible untreated or (3) irradiated (150 krad) ‘Golden Delicious’ pollen, or (4) pollinated with a mixture (2:1 w/w) of irradiated (mentor) pollen and self pollen. After 18 h, nearly the same proportion (> 90%) of the self-incompatible pollen had germinated on the stigma and penetrated the apical part of the style as compatible pollen. However, subsequent growth of the self-pollen tubes was inhibited. After 48 h, less than 1% had reached the stylar base as compared with 21–24% of the compatible pollen tubes. Irradiation strongly impaired pollen vitality: only 1% of the tubes had reached the base of the style after 48 h. The mixture of the irradiated mentor pollen and self pollen performed better. In this case, 6.4–9.9% of the tubes was observed in the basal part of the style, inferring that tube growth of the self pollen was significantly promoted by the mentor pollen.     

The effect of diflubenzuron upon larvae of the geometrid Boarmia (Ascotis) selenaria on avocado leaves

Small (70 mg) Boarmia selenaria larvae fed for 4 days on avocado leaves or alfalfa dipped in aqueous diflubenzuron suspensions suffered from severe developmental disturbances. Similar results were obtained with leaves sprayed in an avocado orchard, with which, in addition, the considerable persistence of diflubenzuron under field conditions could be demonstrated. The substance was also active by topical application against large (500–600 mg) B. selenaria larvae, whereas by contact it was only moderately toxic. Some other non-conventional control agents, viz., the antifeedant AC-24055 and several juvenile hormone analogues, were of medium and negligible activity, respectively, against this insect.     

Contact activity of diflubenzuron against Spodoptera littoralis larvae

The effect of diflubenzuron as a residue on glass or applied topically to Spodoptera littoralis larvae was investigated. Diflubenzuron was active as a residue on glass against 100 and 200 mg larvae; the toxicity of residues was identical whether a dispersable formulation or a wettable powder or the technical substance were used. By topical application, diflubenzuron had an ED₅₀ for cumulative percentage mortality up to the adult stage of 004 and 0066 μg/larva for 100 and 200mg larvae respectively. Neither the site of the topical application nor whether the larvae were kept singly or in groups of ten after the treatment had an influence on toxicity. The data indicate that diflubenzuron has contact toxicity to at least one insect species as well as the known stomach poison action.     

Long chain alkanes in silk extracts of maize genotypes with varying resistance to Fusarium graminearum

The alkane content of the silks of nine maize genotypes was analyzed to investigate the role of silk wax in resistance to Fusarium graminearum. Silk samples were collected 2, 4, 6, and 8 days after silk emergence and divided into three sections: exposed silk, silk channel silk, and silk that is under the husk and overlying the kernels. Four major unbranched alkanes (C(25), C(27), C(29), and C(31)) and three isoalkanes (C(27i), C(29i), and C(31i)) were identified. Total alkane contents were highest in the exposed silk followed by the silk channel silk, with the lowest in the youngest silk closest to the kernels. In the silk channel and overlying kernel silks, the moderately resistant inbred CO272 consistently had the highest alkane content. None of the other inbreds with improved resistance had as high a level of alkanes as CO272, indicating that alkane content is not a major mechanism of resistance.     

Early-age feed restriction affects viability and gene expression of satellite cells isolated from the gastrocnemius muscle of broiler chicks

Background: Muscle growth depends on the fusion of proliferate satellite cells to existing myofibers. We reported previously that 0-14 day intermittent feeding led to persistent retardation in myofiber hypertrophy. However, how satellite cells respond to such nutritional insult has not been adequately elucidated. Results: One-day-old broiler chicks were allocated to control (Con, ad libitum feeding), intermittent feeding (IF, feed provided on alternate days) and re-feeding (RF, 2 days ad libitum feeding after 12 days of intermittent feeding) groups. Chickens were killed on Day 15 and satellite cells were isolated. When cultured, satellite cells from the IF group demonstrated significant retardation in proliferation and differentiation potential, while RF partly restored the proliferation rate and differentiation potential of the satellite cells. Significant up-regulation of insulin like growth factor I receptor (IGF-IR) (P<0.05) and thyroid hormone receptor α (TRα) (P<0.05), and down-regulation of growth hormone receptor (GHR) (P<0.01) and IGF-I (P<0.01) mRNA expression was observed in freshly isolated IF satellite cells when compared with Con cells. In RF cells, the mRNA expression of IGF-I was higher (P<0.05) and of TRα was lower (P<0.01) than in IF cells, suggesting that RF restored the mRNA expression of TRα and IGF-I, but not of GHR and IGF-IR. The Bax/Bcl-2 ratio tended to increase in the IF group, which was reversed in the RF group (P<0.05), indicating that RF reduced the pro-apoptotic influence of IF. Moreover, no significant effect of T 3 was detected on cell survival in IF cells compared with Con (P<0.001) or RF (P<0.05) cells. Conclusions: These data suggest that early-age feed restriction inhibits the proliferation and differentiation of satellite cells, induces changes in mRNA expression of the GH/IGF-I and thyroid hormone receptors in satellite cells, as well as blunted sensitivity of satellite cells to T3 , and that RF partially reverses these effects. Thus, a moderate nutritional strategy for feed restriction should be chosen in early chick rearing systems.