Identification of chronic stress biomarkers in dairy cows

Stress in dairy herds can occur from multiple sources. When stress becomes chronic because of a long duration and inability of animals to adapt, it is likely to deeply affect the emotional state, health, immunity, fertility and milk production of cows. While assessing chronic stress in herds would be beneficial, no real consensus has emerged from the literature regarding the indicators of interest. The goal of this study was to compare and evaluate potential biomarkers for chronic stress after inducing stress over a 4-week period through severe overstocking, restricted access to feed and isolated unusual events. A total of 30 cows were involved in the experiment and two similar groups were constituted. Over a 4-week period, the 15 cows of the stress group were housed in overstocked conditions, with 4.6 m² per cow, including resting and feeding areas. In this area, only seven individual places at the feeding area were available for the 15 cows to generate competition for feed access. Twice during the trial and over a period of 2 h, an additional stress was induced by moving cows to an unfamiliar barn and diffusion of stressing noises (dog barking). Meanwhile, the 15 cows of the control group stayed in the original barn, with more than 10 m² per cow and more individual places at the feeding area than cow number. On a weekly basis, several variables considered as potential biomarkers for chronic stress were recorded. Collected data were analysed using single trait linear repeated mixed models. No differences were observed regarding milk yield, BW of cows or body condition score but the milk loss was more pronounced in the stress group. The activity was more heterogeneous and the rumination of cows was lower in the stress group. The heart rate was lower in the stress group and showed more heterogeneity at the end of the stress period. No differences were observed regarding salivary cortisol, blood glucose, β-endorphin, thyroxine and leucocyte profile. A higher level of hair cortisol and blood fructosamine were observed in the stress group at the end of the stress period. Regarding the practical use of the highlighted biomarkers, milk loss may be an effective and easy way to detect general problems, including stress. The blood fructosamine and the hair cortisol concentrations are promising indicators to assess chronic stress in commercial farms.

Rummaging through the bin: Modelling marine litter distribution using Artificial Neural Networks

Marine litter has significant ecological, social and economic impacts, ultimately raising welfare and conservation concerns. Assessing marine litter hotspots or inferring potential areas of accumulation are challenging topics of marine research. Nevertheless, models able to predict the distribution of marine litter on the seabed are still limited. In this work, a set of Artificial Neural Networks were trained to both model the effect of environmental descriptors on litter distribution and estimate the amount of marine litter in the Central Mediterranean Sea. The first goal involved the use of self-organizing maps in order to highlight the importance of environmental descriptors in affecting marine litter density. The second goal was achieved by developing a multilayer perceptron model, which proved to be an efficient method to estimate the regional quantity of seabed marine litter. Results demonstrated that machine learning could be a suitable approach in the assessment of the marine litter issues.

Sluggish dorsally-driven inhibition of return during orthographic processing in adults with dyslexia

Dyslexia (D) is a neurodevelopmental reading disorder characterized by phonological and orthographic deficits. Before phonological decoding, reading requires a specialized orthographic system for parallel letter processing that assigns letter identities to different spatial locations. The magnocellular-dorsal (MD) stream rapidly process the spatial location of visual stimuli controlling visuo-spatial attention. To investigate the visuo-spatial attention efficiency during orthographic processing, inhibition of return (IOR) was measured in adults with and without D in a lexical decision task. IOR is the delay in responding to stimuli displayed in a cued location after a long cue-target interval. Only adults with D did not showed IOR effect during letter-string recognition, despite the typical left-hemisphere specialization for word identification. A specific deficit in coherent-dot-motion perception confirmed an MD-stream disorder in adults with D. Our results suggest that adults with D might develop an efficient visual word form area, but a dorsal-attentional dysfunction impairs their reading fluency.

First Report of Buxus rotundifolia Root and Collar Rot Caused by Phytophthora citrophthora in Italy

Boxwood (Buxus spp.) includes several species of popular ornamental shrubs used in traditional and contemporary gardening. In March of 2008, a gradual and irreversible decline was observed on 6-year-old Buxus rotundifolia plants in a garden in central Italy. Of 150 boxwood plants, 70% were symptomatic, and among them, approximately 25% were completely wilted. Aboveground symptoms included stunting, necrotic bark lesions at the base of the stem, reduced growth, and leaf chlorosis. Leaves at first appeared light green, then turned yellow, bronze, or straw colored. Foliar symptoms were restricted to a few branches or extended to the whole crown. Immunological field tests (Pocket Diagnostic, CSL Diagnostics, Milan, Italy) on necrotic rootlets and bark tissues suggested the risk of the presence of Phytophthora spp. One species was consistently isolated on PARHP (2) from necrotic tissues of three symptomatic plants. Recovered isolates were heterothallic and produced aerial mycelium. Star-like compact growth was also observed on potato dextrose agar. Cultures on carrot agar submerged in saline solution (2) developed papillate, noncaducous, and sympodially branched sporangia of different shapes ranging from ovoid to obturbinate. Sporangia were 37.5 to 65.0 × 22.5 to 35.0 μm (average 49.0 × 31.0 μm); L/W ratio from 1.1 to 2.1 (average 1.6). On the basis of morphological features, these isolates belong to P. citrophthora (R.E. Sm. & E.H. Sm.) Leonian (2). The identity was confirmed by sequencing of the internal transcribed spacer region of the rDNA (NCBI Accession No. FJ874794). Inoculum for two isolates of P. citrophthora (3BO and 4BO) was produced for pathogenicity testing on 100 g of autoclaved millet grains moistened with 70 ml of V8 juice. Two, 2-liter aliquots of potting media were each amended with the infested grains (1:20 vol/vol) and five 3-year-old plants of B. rotundifolia per isolate were transplanted into the media. Plants were maintained in a growth chamber at 18 to 22°C, with relative humidity of 80%, and a 12-h photoperiod. Sterile millet grains were used to inoculate five boxwood plants for the control. After 2 months, control plants remained healthy while inoculated plants displayed root necroses and foliar symptoms similar to those observed in the field. The pathogen, consistently reisolated from roots of infected plants, reduced the root weight by an average of 25%. Root rot of boxwood plants is reported to be caused by P. citricola in Poland (4), P. parasitica in Virginia (3), and P. citrophthora in North Carolina (1). To our knowledge, this is the first report of P. citrophthora on B. rotundifolia in Europe. References: (1) Z. G. Abad et al. Plant Dis. 78:830, 1994. (2) D. C. Erwin and O. K. Ribeiro. Page 562 in: Phytophthora Diseases Worldwide. The American Phytopathological Society. St. Paul, MN, 1996. (3) M. A. Hansen. Plant Dis. Fact Sheets. 450-614W, 2000. (4) L. B. Orlikowski. J. Plant Prot. Res. 46:163, 2006.

First Report of Root Rot and Twigs Wilting of Olive Trees in Argentina Caused by Phytophthora nicotianae

In Argentina, olives (Olea europaea) are planted on approximately 90,000 ha located primarily in the northwest continental regions. During a 2005 survey, root rot was recorded at several olive plantations in Catamarca, La Rioja, and San Juan provinces (3). Aboveground symptoms associated with root rot were twigs wilting with or without chlorosis, defoliation, and death. Symptoms were initiated on lateral branches and sometimes affected the entire crown. Even if young (5-year-old) trees displayed root rot, aerial symptoms may or may not be seen until years later. Disease incidence varied from 3 to 30%. Rotted rootlets were associated mainly with the infection of Phytophthora palmivora Butler and less frequently with another Phytophthora species. Isolates of this species were heterothallic, had a fluffy growth on carrot agar, and arachnoid growth on potato dextrose agar. Chlamydospores approximately 36 μm in diameter were also produced. The species developed prominent, papillate, noncaducous sporangia of different shapes ranging from ellipsoid to spherical when submerged in saline solution. Sporangia were 35 to 57 × 25 to 45 μm (average 44 × 33 μm), L:B ratio from 1.1 to 1.7. Isolates formed oogonia and amphyginous antheridia following mating type assays. On the basis of morphological features, these isolates were identified as P. nicotianae Breda de Haan. Identity was confirmed by sequencing the rDNA internal transcribed spacer (GenBank Accession No. FJ746693) (1). One-year-old O. europea seedlings were challenged with P. nicotianae (A1 isolates 306G and 339) through soil infestation assay in a growth chamber at 25°C. Infested and uninfested autoclaved millet grains moistened with V8 juice were used to inoculate 15 olive seedlings per isolate and controls, respectively. Fifty days after inoculation, seedlings showed foliar symptoms similar to those observed in the field and had an average of 50% reduction in the root system. Control plants remained healthy. P. nicotianae was always reisolated from symptomatic roots. P. nicotianae was reported on Citrus aurantium in Argentina in 1947 and is currently associated with several hosts (2). In 2002, the same species was reported associated with olive root rot in southern Italy (4). It is possible that P. nicotianae was recently introduced into Argentina through importation of Mediterranean olive varieties. The demonstrated pathogenicity of P. nicotianae on olive together with the recently reported detection of P. palmivora (3) presents a serious threat to olive cultivation in Argentina. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) M. J. Frezzi. Rev. Investig. Agric. 4:47, 1950. (3) G. Lucero et al. Plant Pathol. 56:728, 2007. (4) F. Nigro and A. Ippolito. Acta Hortic. 586:777, 2002.

The in vitro effect of gossypol and its interaction with salts on conidial germination and viability of Fusarium oxysporum sp. vasinfectum isolates

AIMS

To assess the effect of different concentrations of gossypol (0, 2, 4, 10 and 20 mg l(-1)) in combination with NaCl and Na(2)SO(4) (20 mS cm(-1)) on the conidial germination and viability of Fusarium oxysporum f.sp. vasinfectum (Fov).

METHODS AND RESULTS

A multinomial logistic model was developed to estimate the germination probability of Fov. The inhibitory effect was markedly evident at the two highest concentrations of gossypol; it varied among the isolates tested and with time, and it was attenuated by the presence of sodium salts. The inhibition was temporary as the germination probability increased after 8 h. Fluorescent staining revealed that gossypol either killed the conidia or retarded the elongation of the germ tubes.

CONCLUSION

Fov showed the ability to overcome gossypol inhibition over time, and the inhibitory effect is reduced under saline conditions. Differential responses among Fov isolates to the presence of gossypol suggest that gossypol tolerance is genetically determined in the pathogen.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that selecting for high plant gossypol cultivars would have minimal effect on the overall Fov resistance of cotton. A new statistical model was developed to explore the statistical significance of plant-pathogen interactions.

Phenotype and genotype of Candida albicans strains isolated from pregnant women with recurrent vaginitis

Fourteen out of 80 pregnant women receiving prenatal care presented signs and symptoms of recurrent vaginal candidiasis. Candida albicans strains were isolated from 12 patients (85.7%), and these were submitted to morphotyping (morphological characteristics of the colony), antifungal typing (pattern of sensitivity to amphotericin B, 5-fluorcytosine, myconazole, ketoconazole and fluconazole) and genotyping (electrophoretic migration of DNA fragments digested with EcoRI and HinfI). Alteration of morphotype and antifungal type was observed in 50% of the patients, but the genotype of the strains isolated from the same patients at different times was identical in all subjects. The predominant morphotypes presented continuous fringes and the basic changes observed among antifungal types was the emergence of strains resistant to myconazole, which was the drug used for the treatment of the first episode of vaginitis. We conclude that recurrent vaginal candidasis is caused by the persistence of a single yeast genotype that undergoes morphological and behavioral changes in the presence of antifungal agents due to the selective pressure to which it is submitted.

[Preservation at -195 degrees C of trypsinized organs for primary cultures]

Trypsinized cells from rabbit kidney can be kept at -195, 8 degrees C indefinitely. When necessary, propagation in monolayer cultures is readily obtained as primary cultures, provided that some conditions be respected: 1) only glass culture flask must be used. Falcon plastic vessels do not allow cell attachment in this type of primary culture 2) the lag period is particularly long: it taken about 20 days before the beginning of cell multiplication 3) fetal calf serum is toxic for the cells in the 2nd and 3rd change of the culture medium, during the lag period.

[Intestinal secretory IgA and bacterial antigens in oral administration]

The proposed technique for purification and concentration of secretory IgA has been applied to intestinal wash fluids obtained by clisma from 15 patients under bacterial extracts treated (COLOPTENE-DEBAT). The collected data show that the technique is suitable for routinary use and the bacterial extracts do increase the amount of IgA in the intestinal contents.