An Outbreak of Gangrenous Syndrome among Buffaloes and Cattle in West Bengal: Clinicopathological Studies

Gangrenous syndrome/Degnala disease was recorded in a large number of buffaloes and cattle in Murshidabad district of West Bengal, India. Fusarium spp. had been isolated from the mouldy paddy straw which were fed to the animals. There was a reduction in the incidence of the disease following withdrawal of the mouldy paddy straw. Histopathological examination showed necrosis and loss of architectural details in the skin.     

Intra-specific patterns of δ13C,growth and wood density variation at sites of contrasting precipitation with implications for modelling carbon sequestration of tropical tree species

Agroforestry Systems - Tropical agroforestry practices play a crucial role in mitigating global climate change by absorbing CO2 from the atmosphere through photosynthesis and storing carbon in...     

A case of habitat complementation in forest pests: Pine processionary moth pupae survive better in open areas

Little attention has been given to the relevance of habitat complementation concept to the population dynamics of insect herbivores. Late instar larvae of the pine processionary moth (PPM) Thaumetopoea pityocampa move in late winter from pine stands, their feeding habitat, to neighbouring habitats where they pupate until next summer. They search for sunny exposed soil which they can find in open areas. We investigated the effect of both forest cover and soil origin, with three matching types (pine stand, broadleaved stand and open area) on the survival of PPM pupae. The microclimatic soil variables which significantly differentiated cover types and soil origins were the maximum temperature and the mean relative humidity in spring, soon after pupation has occurred. A significant effect of the cover type, but not of the soil origin, was detected on the proportion of dead, emerged or diapausing pupae. Open areas were more suitable for pupae survival than forest covers (pine or broadleaved stands), due to warmer and more humid soil conditions. In this study, we provide one of the first examples of habitat complementation for an insect herbivore, as PPM population can benefit from the combination of pine habitats for the feeding of larvae with open habitats for pupation. The presence of broadleaved stands next to pine stands might also represent an ecological trap for PPM pupae, as broadleaved habitats may turn to be less suitable for pupae survival in spring when the apparition of leaves creates cooler conditions.     

Guest-dependent spin crossover in a nanoporous molecular framework material

The nanoporous metal-organic framework Fe2(azpy)4(NCS)4.(guest) (azpy is trans-4,4'-azopyridine) displays reversible uptake and release of guest molecules and contains electronic switching centers that are sensitive to the nature of the sorbed guests. The switching of this material arises from the presence of iron(II) spin crossover centers within the framework lattice, the sorbed phases undergoing "half-spin" crossovers, and the desorbed phase showing no switching property. The interpenetrated framework structure displays a considerable flexibility with guest uptake and release, causing substantial changes in the local geometry of the iron(II) centers. The generation of a host lattice that interacts with exchangeable guest species in a switchable fashion has implications for the generation of previously undeveloped advanced materials with applications in areas such as molecular sensing.     

Butterfly dispersal in farmland: a replicated landscape genetics study on the meadow brown butterfly (<Emphasis Type="Italic">Maniola jurtina</Emphasis>)

Context

Anthropogenic activities readily result in the fragmentation of habitats such that species persistence increasingly depends on their ability to disperse. However, landscape features that enhance or limit individual dispersal are often poorly understood. Landscape genetics has recently provided innovative solutions to evaluate landscape resistance to dispersal.

Objectives

We studied the dispersal of the common meadow brown butterfly, Maniola jurtina, in agricultural landscapes, using a replicated study design and rigorous statistical analyses. Based on existing behavioral and life history research, we hypothesized that the meadow brown would preferentially disperse through its preferred grassy habitats (meadows and road verges) and avoid dispersing through woodlands and the agricultural matrix.

Methods

Samples were collected in 18 study landscapes of 5 × 5 km in three contrasting agricultural French regions. Using circuit theory, least cost path and transect-based methods, we analyzed the effect of the landscape on gene flow separately for each sex.

Results

Analysis of 1681 samples with 6 microsatellites loci revealed that landscape features weakly influence meadow brown butterfly gene flow. Gene flow in both sexes appeared to be weakly limited by forests and arable lands, whereas grasslands and grassy linear elements (road verges) were more likely to enhance gene flow.

Conclusion

Our results are consistent with the hypothesis of greater dispersal through landscape elements that are most similar to suitable habitat. Our spatially replicated landscape genetics study allowed us to detect subtle landscape effects on butterfly gene flow, and these findings were reinforced by consistent results across analytical methods.

     

Multiscale spatial variation of the bark beetle Ips sexdentatus damage in a pine plantation forest (Landes de Gascogne,Southwestern France)

Bark beetles are notorious pests of natural and planted forests causing extensive damage. These insects depend on dead or weakened trees but can switch to healthy trees during an outbreak as mass-attacks allow the beetle to overwhelm tree defences. Climatic events like windstorms are known to favour bark beetle outbreaks because they create a large number of breeding sites, i.e., weakened trees and for this reason, windthrown timber is generally preventively harvested and removed. In December 1999, the southwest of France was struck by a devastating windstorm that felled more that 27 million m³of timber. This event offered the opportunity to study large-scale spatial pattern of trees attacked by the bark beetle Ips sexdentatus and its relationship with the spatial location of pine logs that were temporally stored in piles along stand edges during the post-storm process of fallen tree removal. The study was undertaken in a pure maritime pine forest of 1300 ha in 2001 and 2002. We developed a landscape approach based on a GIS and a complete inventory of attacked trees. During this study more than 70% of the investigated stands had at least one tree attacked by I. sexdentatus  . Spatial aggregation prevailed in stands with n≥15$n\ge 15$ attacked trees. Patches of attacked trees were identified using a kernel estimation procedure coupled with randomization tests. Attacked trees formed patches of 500–700 m² on average which displayed a clumped spatial distribution. Log piles stemming from the sanitation removals were mainly distributed along the large access roads and showed an aggregated spatial pattern as well. The spatial relationship between patches of attacked trees and log pile storage areas was analyzed by means of the Ripley’s statistic that revealed a strong association at the scale of the studied forest. Our results indicated that bark beetle attacks were facilitated in the vicinity of areas where pine logs were stored. The spatial extent of this relationship was >1000 m. Similar results were obtained in 2001 and 2002 despite differences in the number and spatial distribution of attacked trees. The presence of a strong “facilitation effect” suggests that log piles should be removed quickly in order to prevent outbreaks of bark beetles.     

Effects of Presprouting, Planting Date, Plant Population and Configuration on Late Blight and Yield of Organic Potato Crops Grown with Different Cultivars

In organic systems of agriculture, integrated control strategies are necessary for the management of late blight. Agronomic treatments such as presprouting of seed tubers, planting early and in different populations and spacings should be considered for inclusion. They may delay and/or decrease infection and help to ensure that acceptable marketable yields are achieved before the disease prevails. Individually, their efficacy may be limited, but in combination with other components the integrated strategy may be more successful. Experiments in the UK and the Netherlands tested some potential components of such a strategy: presprouting (chitting) and early planting of seed tubers, which should encourage early bulking and evasion of the disease; choice of plant population and configuration to make the crops’ microclimate less favourable for infection. Both early planting and presprouting (chitting) gave higher yields earlier in the season, before late blight put an end to crop growth, and were most effective in years with a short growing season (e.g., when the disease started early). Plant population and spacings within commercially acceptable limits had marked effects on canopy architecture but no effects on late blight infection. However, the effects on tuber size grading were large. At lower densities, tubers were larger on average. This was an advantage when blight infection was early, but could result in the production of too many oversized tubers if it was delayed or absent, unless the crop was defoliated.     

Non-Host Volatiles Disrupt the Response of the Stenographer Bark Beetle, Ips sexdentatus (Coleoptera: Scolytidae), to Pheromone-Baited traps and Maritime Pine Logs

Non-host volatiles (NHV) were tested on antennae of Ips sexdentatus with coupled gas chromatographic-electroantennographic detection (GC-EAD). Significant antennal responses were found to aggregation pheromone components, ipsdienol and amitinol, an attraction inhibitor, verbenone, and non-host bark volatiles extracted from Betula pendula, including trans-conophthorin (tC) and alcohols. The tC, a blend of three green leaf alcohols (C6-alcohols), and a blend of two bark alcohols (C8-alcohols) were tested in combination for their ability to disrupt the attraction of the stenographer bark beetle to pheromone-baited traps, unbaited and pheromone-baited maritime pine logs. The strongest disruptive effect resulted from the addition of the tC combined with the blends of NHV alcohols at high release rate, achieving an 83% reduction in trap catches, 89% reduction of attacks on unbaited pine logs, and 60% on baited logs. It is proposed that the two types of NHV have an additive effect, tC playing a major role in pheromone disruption while the alcohols would interrupt host specific signals. The results suggest that I. sexdentatus uses both bark and green leaf volatiles from non-host tree species in the host selection process. These NHV are promising disruptants, which could be used to prevent stenographer bark beetle attacks on log piles or standing trees in forest. A mixture of conifers and broad-leaved species would also disturb olfactory guided host selection supporting the assumption that more diverse forests are less prone to pest insect outbreaks.     

Bovine brucellosis – a comprehensive review

Brucellosis is a zoonotic disease of great animal welfare and economic implications worldwide known since ancient times. The emergence of brucellosis in new areas as well as transmission of brucellosis from wild and domestic animals is of great significance in terms of new epidemiological dimensions. Brucellosis poses a major public health threat by the consumption of non-pasteurized milk and milk products produced by unhygienic dairy farms in endemic areas. Regular and meticulous surveillance is essentially required to determine the true picture of brucellosis especially in areas with continuous high prevalence. Additionally, international migration of humans, animals and trade of animal products has created a challenge for disease spread and diagnosis in non-endemic areas. Isolation and identification remain the gold standard test, which requires expertise. The advancement in diagnostic strategies coupled with screening of newly introduced animals is warranted to control the disease. Of note, the diagnostic value of miRNAs for appropriate detection of B. abortus infection has been shown. The most widely used vaccine strains to protect against Brucella infection and related abortions in cattle are strain 19 and RB51. Moreover, it is very important to note that no vaccine, which is highly protective, safe and effective is available either for bovines or human beings. Research results encourage the use of bacteriophage lysates in treatment of bovine brucellosis. One Health approach can aid in control of this disease, both in animals and man.