Significant Species Effect Research Articles

Seroprevalence of Bovine ephemeral fever virus in Gujarat State of India.

Bovine ephemeral fever (BEF) virus (BEFV) is an arthropod borne virus that causes bovine ephemeral fever or three‑day sickness in cattle and buffaloes. This is the first report on seroprevalence of BEF in cattle and buffaloes in Gujarat, India. Total of 92 animals, 78 cattle and 14 buffaloes from three regions (districts) of Gujarat state of India, were screened for the presence of anti‑BEF antibodies. A total of 27 out of 92 animals were found positive and overall seroprevalence detected was 29.34% (95% CI 20.0‑38.6%). A total of 19 out of 78 cattle and 8 out of 14 buffalo's samples were found positive BEFV antibodies. Species‑wise seroprevalence in cattle and buffaloes was 24.35% (95% CI 14.8‑33.8%) and 57.1% (95% CI 31.2‑83.0%), respectively. There was a statistically significant (p < 0.05) species effect based on the seroprevalence. In cattle, location‑wise seroprevalence was observed to be 26.82% (95% CI 13.2‑40.3%) and 21.62% (95% CI 8.3‑34.8%) in Navsari and Banaskantha districts, respectively. The effect of location is not statistically significant (p < 0.05). Cytopathic effect of Vero cells was characterized by rounding, granulation of the cytoplasm within 48‑72 hrs of post infection. This was the first report demonstrating the presence of BEFV in Gujarat state.

Comparison of True Ileal Amino Acid Digestibility between Adult Humans and Growing Pigs

It is not feasible to determine the true ileal amino acid (AA) digestibility of protein sources in humans on a routine basis, and the growing pig has been recommended as an animal model for this purpose but requires further validation. To determine and compare true ileal AA digestibility between adult human ileostomates and growing cannulated pigs for a range of food proteins. Seven protein sources (black beans, bread, collagen, pigeon peas, wheat bran, whey protein isolate, and zein) that spanned the range of digestibilities typically seen in foods were evaluated. Six female growing pigs received each of the protein sources, as well as a protein-free diet, and digesta were collected via ileal T-cannula. Adult human ileostomates consumed the same protein sources (5-8 ileostomates, depending on the protein source), as well as a protein-free diet, and digesta were collected. Titanium dioxide and celite were included in the diets as indigestible markers. True ileal AA digestibility coefficients were determined. There was a significant effect of protein source (P≤0.001) for all AAs. The effect of species was not significant (P>0.05) except for total lysine (but not for available lysine). When analyzed within diets, the statistically significant species effect for true lysine digestibility was found for black beans only. Pig and human digestibility values were generally highly and significantly (P≤0.05) correlated. A linear regression equation derived for true ileal AA digestibility (given as coefficients) determined in the human and pig for the overall mean of all AAs was (y=human, x=pig) y=1.00x - 0.010, with the slope not statistically significant (P>0.05) from unity and the intercept not different (P>0.05) from zero. True ileal AA digestibility values determined in the growing pig can be directly used for predicting digestibility in adult humans.

Early evaluation of genetic parameters in clonal propagation of bamboo species

Bamboo plantation has gained great attention in Brazil due to its useful production provided to the society and the ecological, economic, social and cultural functions of these plantations. For the establishment of high productivity plantations, evaluation of germplasm and selection of superior genotypes is necessary. This work aimed at early evaluation of the genetic parameters of potential bamboo species for planting in Brasília/DF. For this purpose, a clonal test consisting of seven species was established: Bambusa oldhamii, Bambusa vulgaris, Bambusa vulgaris var. vittata, Dendrocalamus asper, Dendrocalamus latiflorus, Guadua angustifolia and Guadua chacoensis. The experiment was planted in a completely randomized block design, with three replications and fifteen plants per plot. At 360 days after planting, all individuals were evaluated for their characteristics: height of aerial part, number of sprouts, clump base area, clump coverage area and density of stalks per clump. The statistical analyses were carried out through the procedure of mixed models: Maximum Residual Likelihood/Better Non-Victimised Linear Prediction. There were significant species effects on the characteristics of the aerial part height and number of shoots, as well as high estimates of selective accuracies. Genetic parameters and genotypic values demonstrate genetic variability between species and the possibility of future gains from selection. New evaluations will be carried out annually to aim a greater knowledge of the behavior of germplasms at different ages. At the age of five (commercial court), the best genotypes will be selected for the experimental environmental conditions.

Vigilance strategy differentiation between sympatric threatened and common crane species

Studies have indicated that threatened species may show reduced or elevated antipredator behavior compared with their close common relatives, but remarkably few studies revealed such differences in behavior among populations. Exploring factors affecting behavior between phylogenetically related common and threatened species could help understand such discrepancy. We tested for effects of external and internal variables including month, time of day, habitat type, distribution area, group composition status and group size on vigilance behavior (including group scan frequency and level) of two sympatric common Grus grus and threatened G. nigricollis cranes with generalized linear models. We detected significant species effect on group scan level, and grus was more vigilant than nigricollis. Model tests also indicated that group size had common effect on group scan frequency for both species, and distribution area significantly correlated with the vigilance of nigricollis, while grus was more affected by time of day and group composition status in areas of sympatry with nigricollis. But when nigricollis was absent, time had no effects on behavior by individuals belonging to grus, implying existence of inter-specific competition. We also found that grus decreased individual vigilance efforts by foraging with other species (e.g., Bar-headed Goose Anser indicus) to share large group alertness benefits (collective vigilance). As our results demonstrated, we argued that, with diverse antipredation tactics e.g., foraging with other species, alternating time rhythm or partitioning spatial utilization to mitigate inter-specific competition, reducing time allocation to preening while maintaining foraging efforts, common grus could maintain high level of vigilance, which may benefit their survival and population increase. Whereas less time spent vigilant antipredation strategy adopted by threatened nigricollis, this may have negative effects on their populations.

Origins of the sweetness derived from the aging of dry wines: the role of oak triterpenoids

Aging in barrel affects the sensory characteristics of wines and modifies the sweet taste in particular. Using an inductive approach, several sweet triterpenes, QTTs, have been identified in oak. Quantitative analysis has shown a significant species effect: sessile oak releases more sweet triterpenes while pedunculate oak is richer in bitter triterpenes. It is now possible to differentiate the two species on the basis of their triterpene composition.

Seeking stable traits to characterize the root system architecture. Study on 60 species located at two sites in natura.

In several disciplines, identifying relevant root traits to characterize the root system architecture of species or genotypes is a crucial step. To address this question, we analysed the inter-specific variations of root architectural traits in two contrasting environments. We sampled 60 species in natura, at two sites, each presenting homogeneous soil conditions. We estimated for each species and site a set of five traits used for the modelling of the root system architecture: extreme tip diameters (Dmin and Dmax), relative diameter range (Drange), mean inter-branch distance (IBD) and dominance slope between the diameters of parent and lateral roots (DlDm). The five traits presented a highly significant species effect, explaining between 77 and 98 % of the total variation. Dmin, Dmax and Drange were particularly determined by the species, while DlDm and IBD exhibited a higher percentage of environmental variations. These traits make it possible to confirm two main axes of variation: 'fineness-density' (defined by Dmin and IBD) and 'dominance-heterorhizy' (DlDm and Drange), that together accounted for 84 % of the variations observed. We confirmed the interest of these traits in the characterization of the root system architecture in ecology and genetics, and suggest using them to enrich the 'root economic spectrum'.

Faecal N excretion as an approach for estimating organic matter intake by free-ranging sheep and cattle

AbstractThe current study aimed to test whether organic matter intake by free-ranging ruminants could be estimated from the amount of nitrogen (N) excreted in faeces and to compare this approach to conventional techniques. An equation describing the relationship between excreted N and nutrient intake was developed in indoor digestibility trials conducted with male sheep (n= 36) and cattle (n= 24) housed in metabolism cages and solely fed hay harvested from a local rangeland. Faecal N excretion was linearly related to organic matter (OM) intake without a significant animal species effect. To evaluate the linear equation, data from free-ranging trials conducted with sheep and cattle were used. The faecal N approach was compared with eitherin situdigestibility plus external marker (n= 123) orn-alkanes (n= 272) to estimate OM intake and digestible OM intake. Estimates obtained through the faecal N approach did not closely fit those obtained with either conventional technique for any variable. Averaging all individual values, the supply of metabolizable energy (ME) estimated through faecal N was similar to the required level, whereas both thein situandn-alkanes techniques overestimated ME supply. In conclusion, OM intake by free-ranging sheep and cattle can be estimated based on the amount of N excreted in faeces with some advantages over conventional techniques: knowledge about herbage attributes is not required and it accounts for individual variability on selectivity and digestion processes.

Allometric equations of select tree species of the Tibetan Plateau, China

The Tibetan forest is one of the most important national forest zones in China. Despite the potentially important role that Tibetan forest will play in the Earth’s future carbon balance and climate regulation, few allometric equations exist for accurately estimating biomass and carbon budgets of this forest. In the present study, allometric equations, both species-specific and generic, were developed relating component biomass (DW) to diameter at breast height (DBH) and tree height (H) for six most common tree species in Tibetan forest. The 6 species were Abies georgei Orr., Picea spinulosa (Griff.) Henry, Pinus densata Mast., Pinus yunnanensis Franch., Cypresses funebris Endl. and Quercus semecarpifilia Smith.. The results showed that, both DBH-only and DBH2H based species-specific equations showed a significant fit (P<0.05) for all tree species and biomass components. The DBH-only equations explained more than 80% variability of the component biomass and total biomass, adding H as a second independent variable increased the goodness of fit, while incorporating H into the term DBH2H decreased the goodness of fit. However, not all DBH-H combined equations showed a significant fit (P<0.05) for all tree species and biomass components. Hence, the suggested species-specific allometric equations for the six most common tree species are of the form ln(DW) = c + αln(DBH). The generalized equations of mixed coniferous component biomass against DBH, DBH2H and DBH-H also showed a significant fit (P<0.05) for all biomass components. However, due to significant species effect, the relative errors of the estimates were very high. Hence, generalized equations should only be used when there are too many different tree species, or there is no species-specific model of the same species or similar growth form in adjacent area.

Fall and Winter Survival of Brook Trout and Brown Trout in a North‐Central Pennsylvania Watershed

AbstractStream‐dwelling salmonids that spawn in the fall generally experience their lowest survival during the fall and winter due to behavioral changes associated with spawning and energetic deficiencies during this time of year. We used data from Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta implanted with radio transmitters in tributaries of the Hunts Run watershed of north‐central Pennsylvania to estimate survival from the fall into the winter seasons (September 2012–February 2013). We examined the effects that individual‐level covariates (trout species, size, and movement rates) and stream‐level covariates (individual stream and cumulative drainage area of a stream) have on survival. Brook Trout experienced significantly lower survival than Brown Trout, especially in the early fall during their peak spawning period. Besides a significant species effect, none of the other covariates examined influenced survival for either species. A difference in life history between these species, with Brook Trout having a shorter life expectancy than Brown Trout, is likely the primary reason for the lower survival of Brook Trout. However, Brook Trout also spawn earlier in the fall than Brown Trout and low flows during Brook Trout spawning may have resulted in a greater risk of predation for Brook Trout compared with Brown Trout, thereby also contributing to the observed differences in survival between these species. Our estimates of survival can aid parameterization of future population models for Brook Trout and Brown Trout through the spawning season and into winter.Received September 9, 2016; accepted March 6, 2017 Published online May 26, 2017

Fertility-dependent effects of ectomycorrhizal fungal communities on white spruce seedling nutrition.

Ectomycorrhizal fungi (EcMF) typically colonize nursery seedlings, but nutritional and growth effects of these communities are only partly understood. To examine these effects, Picea glauca seedlings collected from a tree nursery naturally colonized by three dominant EcMF were divided between fertilized and unfertilized treatments. After one growing season seedlings were harvested, ectomycorrhizas identified using DNA sequencing, and seedlings analyzed for leaf nutrient concentration and content, and biomass parameters. EcMF community structure-nutrient interactions were tested using nonmetric multidimensional scaling (NMDS) combined with vector analysis of foliar nutrients and biomass. We identified three dominant species: Amphinema sp., Atheliaceae sp., and Thelephora terrestris. NMDS + envfit revealed significant community effects on seedling nutrition that differed with fertilization treatment. PERMANOVA and regression analyses uncovered significant species effects on host nutrient concentration, content, and stoichiometry. Amphinema sp. had a significant positive effect on phosphorus (P), calcium and zinc concentration, and P content; in contrast, T. terrestris had a negative effect on P concentration. In the unfertilized treatment, percent abundance of the Amphinema sp. negatively affected foliar nitrogen (N) concentration but not content, and reduced foliar N/P. In fertilized seedlings, Amphinema sp. was positively related to foliar concentrations of N, magnesium, and boron, and both concentration and content of manganese, and Atheliaceae sp. had a negative relationship with P content. Findings shed light on the community and species effects on seedling condition, revealing clear functional differences among dominants. The approach used should be scalable to explore function in more complex communities composed of unculturable EcMF.

Molecular and oenological characterization of Touriga Nacional non-Saccharomyces yeasts.

The aim of this study was to evaluate non-Saccharomyces yeasts isolated from spontaneous fermenting musts of Touriga Nacional (TN), one of the most important Portuguese red grape variety, to improve and diversify TN wines. Two hundred and seventy nine isolates were assigned to 11 yeast species by conventional molecular and growth tests. Starmerella bacillaris was the most frequently detected yeast species, followed by Hanseniaspora guilliermondii and Hanseniaspora uvarum. Twenty-three isolates from 10 species were selected for oenological study, namely fermentation performance, physicochemical and quantitative descriptive sensory analysis of the wines produced. A significant species effect was observed for most of the variables evaluated, some species generating wines with quite interesting aromas. Candida diversa and S.bacillaris isolates produced wines with higher overall quality, higher balance and more intense and diverse aroma. Furthermore, S.bacillaris isolates generated wines with enhanced TN typical aroma, such as bergamot, violet and rock-rose, and were thus regarded as the most promising for improving TN wines. This study revealed the diversity of wine aroma profiles generated by non-Saccharomyces yeast isolates. This knowledge is particularly important given the growing trend from industry to use non-Saccharomyces yeasts as a tool for improving and diversifying the sensory characteristics of wine.

Species associations in a species-rich subtropical forest were not well-explained by stochastic geometry of biodiversity.

The stochastic dilution hypothesis has been proposed to explain species coexistence in species-rich communities. The relative importance of the stochastic dilution effects with respect to other effects such as competition and habitat filtering required to be tested. In this study, using data from a 25-ha species-rich subtropical forest plot with a strong topographic structure at Badagongshan in central China, we analyzed overall species associations and fine-scale species interactions between 2,550 species pairs. The result showed that: (1) the proportion of segregation in overall species association analysis at 2 m neighborhood in this plot followed the prediction of the stochastic dilution hypothesis that segregations should decrease with species richness but that at 10 m neighborhood was higher than the prediction. (2) The proportion of no association type was lower than the expectation of stochastic dilution hypothesis. (3) Fine-scale species interaction analyses using Heterogeneous Poisson processes as null models revealed a high proportion (47%) of significant species effects. However, the assumption of separation of scale of this method was not fully met in this plot with a strong fine-scale topographic structure. We also found that for species within the same families, fine-scale positive species interactions occurred more frequently and negative ones occurred less frequently than expected by chance. These results suggested effects of environmental filtering other than species interaction in this forest. (4) We also found that arbor species showed a much higher proportion of significant fine-scale species interactions (66%) than shrub species (18%). We concluded that the stochastic dilution hypothesis only be partly supported and environmental filtering left discernible spatial signals in the spatial associations between species in this species-rich subtropical forest with a strong topographic structure.

Role of six European tree species and land‐use legacy for nitrogen and water budgets in forests

AbstractWater and nutrient fluxes for single stands of different tree species have been reported in numerous studies, but comparative studies of nutrient and hydrological budgets of common European deciduous tree species are rare. Annual fluxes of water and inorganic nitrogen (N) were established in a 30‐year‐old common garden design with stands of common ash (Fraxinus excelsior), European beech (Fagus sylvatica L.), pedunculate oak (Quercus robur), small‐leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus) and Norway spruce (Picea abies [L.] Karst.) replicated at two sites in Denmark, Mattrup and Vallø during 2 years. Mean annual percolation below the root zone (mm yr−1±SE, n=4) ranked in the following order: maple (351±38)&gt;lime (284±32), oak (271±25), beech (257±30), ash (307±69)≫ spruce (75±24). There were few significant tree species effects on N fluxes. However, the annual mean N throughfall flux (kg N ha−1 yr−1±SE, n=4) for spruce (28±2) was significantly larger than for maple (12±1), beech (11±1) and oak (9±1) stands but not different from that of lime (15±3). Ash had a low mean annual inorganic N throughfall deposition of 9.1 kg ha−1, but was only present at Mattrup. Annual mean of inorganic N leaching (kg ha−1 yr−1±SE, n=4) did not differ significantly between species despite of contrasting tree species mean values; beech (25±9)&gt;oak (16±10), spruce (15±8), lime (14±8)≫ maple (1.9±1), ash (2.0±1). The two sites had similar throughfall N fluxes, whereas the annual leaching of N was significantly higher at Mattrup than at Vallø. Accordingly, the sites differed in soil properties in relation to rates and dynamics of N cycling. We conclude that tree species affect the N cycle differently but the legacy of land use exerted a dominant control on the N cycle within the short‐term perspective (30 years) of these stands.

Within plant resistance to water flow in tomato and sweet melons

Efficient water resource management in relation to water use and crop yields is premised on the knowledge of plant resistance to water flow. However, such studies are limited and for most crops, the within plant resistance to water flow remains largely unknown. In this study, within plant resistance to water transport (hydraulic conductance) was monitored in tomato (Lycopersicum esculuntum) and sweet melon (Citrullus lanatus) using the high pressure flow meter (HPFM) and evaporative flux (EF) methods. In the evaporative flux method, measurements of transpiration flux and leaf water potential were used to calculate the total resistance to water flow using Ohm’s law analogy. Measurements of tranpiration flux (Q) relationship, plant resistance calculated from the slope of their relationship, ranged from 6.57x10-01 to 2.27x10-03 Mpa m-2s-1 for tomato and sweet melon, respectively.The magnitude of whole plant hydraulic conductance calculated by the evaporative flux method and measured on the HPFM were not significantly different. This is probably due to that fact that Kp includes the hydraulic conductance of the root system, which offers the highest resistance to water flow in a plant, and the frictional resistance of the proximal part of the crown. Day time course of water relation parameters were monitored in melon and tomato (predawn, 1100 to 1400 h). The effect of time of day was pronounced on the dynamics of water relations, particularly around mid-day when sharp differences in the magnitudes of the measured water relation parameters were obtained. Minimum (predawn) leaf water potential (øl) ranged from 0.135 to 0.207 MPa for both crops. The greatest conductance was found in the leaf and the lowest in the root in both crops. While the highest within plant resistance to the flow is contained in the root system, the stemcomponent constitutes the least resistance (greatest conductance) to within plant flow of water in tomato. Repeated measurement analysis showed the existence of significant species effects on plant water relations (leaf water potential, evaporative/transpiration flux, xylem hydraulic conductance). Superiority within plant xylem transport and evaporative losses were obtained in tomato, from the relations of EF and Kh; this crop showed a higher hydraulic sufficiency than melon. The expression of hydraulic conductance of the root and shoot systemrelative to plant attributes did not eliminate differences in the magnitudes of conductance elements in tomato and melon. Differences obtained between melon and tomato in whole plant leaf and stem area specific hydraulic conductance (KI) indicate the carbon efficiency and, hence, the cost of resource allocation to areas of root surfaceand leaves for enhanced scavenging for water and mineral nutrients. Thus, application of mineral nutrients to enhance crop productivity should take into consideration the hydraulic conductance for specific plants.

Rearing unit-level factors associated with bacterial gill disease treatment in two Ontario, Canada government salmonid hatcheries

Early-rearing salmonids in Ontario Ministry of Natural Resources (OMNR) fish hatcheries have been consistently affected by bacterial gill disease (BGD) (causative agent: Flavobacterium branchiophilum) for many years. Separate retrospective epidemiological investigations of BGD treatments at two OMNR fish hatcheries (Hatcheries A and B) for the 1999 production year were conducted using on-site hatchery records. Both investigations were carried out at the rearing unit-level, with early-rearing (<9 months of age) “tank-lot” as the unit of analysis to identify unique fish populations over time. Multivariable repeated measures logistic regression models were created for both hatchery datasets, controlling for lot-level and species effects. For Hatchery A, the species brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) were significantly associated with BGD treatment, as well as lower water exchange rate, and higher feeding and mortality percentages during the 2 weeks previous to BGD treatment. At Hatchery B, the species brook trout (S. fontinalis) and splake (Salvelinus namaycush×S. fontinalis) were significantly associated with BGD treatment, as well as lower individual fish weights and treatment for BGD during the previous week. These results emphasize the importance of water quality, feeding rate, fish size and prior mortality on the development of BGD. Significant hatchery and species effects were evident, and future observational research on BGD must account for these factors in their design and analysis.

Fractionation of silicon isotopes during biogenic silica dissolution

Silicon isotopes have been investigated for their potential to reveal both past and present patterns of silicic acid utilization, primarily by diatoms, in surface waters of the ocean. Interpretation of this proxy has thus far relied on characteristic trends in the isotope composition of the dissolved and particulate silicon pools in the upper ocean, as driven by biological fractionation during the production of biogenic silica (bSiO 2, or opal) by diatoms. However, other factors which may influence the silicon isotope composition of diatom opal, particularly post-formational aging and maturation processes, remain largely uninvestigated. Here, we report a consistent fractionation of silicon isotopes during the physicochemical dissolution of diatom bSiO 2 suspended in seawater under closed conditions. This fractionation acts counter to that occurring during bSiO 2 production and at about half its absolute magnitude, with dissolution discriminating against the release of the heavier isotopes of silicon at an enrichment factor ε DSi–BSi of −0.55‰, corresponding to a fractionation factor α 30/28 of 0.99945. The enrichment factor did not vary with source material, indicating the lack of a significant species effect, or with temperature from 3 to 20 °C. Thus, the dissolution of bSiO 2 produces dissolved silicon with a δ 30Si value that is 0.55‰ more negative than its parent bSiO 2, an effect that must be accounted for when interpreting oceanic δ 30Si distributions. The δ 30Si values of both the dissolved and particulate silicon pools increased linearly as dissolution progressed, implying a measurable (±0.1‰) change in the relative δ 30Si of opal samples whenever the difference in preservation efficiency between them is >20%. This effect could account for ∼10–30% of the difference in diatom δ 30Si values observed between glacial and interglacial conditions. It is unlikely, however, that the inferred maximum possible change in δb 30SiO 2 of +0.55‰ would be manifested in situ, as a high mean percentage of dissolution would include complete loss of the more soluble members of the diatom assemblage.

Grazing and assimilation rate estimates of hydromedusae from a temperate tidal creek system

Previous research implicates gelatinous zooplankton grazing for reducing microzooplankton populations and influencing pelagic carbon fluxes. The principal objective of this study was to determine in situ ingestion rates and assimilation efficiencies for seasonal hydromedusae populations in North Inlet, SC, USA. Hydromedusae collected during July 2005, 2006 and January 2006 were exposed to natural plankton communities that were previously radiolabeled with 14C. Ingestion rates and assimilation efficiencies were calculated from measurements of hydromedusae tissue radioactivity after ingestion and egestion, respectively. Net tows determined that the numerically dominant gelatinous predators in this system were Bougainvillia muscus (July 2005, 2006) and Nemopsis bachei (January 2006). Summer ingestion rates for B. muscus significantly increased with increased temperature, but there was no effect of temperature on winter ingestion rates for N. bachei, suggesting temperature responses are species specific. Moreover, there was a significant species effect on ingestion rates for July 2006. Hydromedusae assimilation efficiencies are relatively constant throughout the year and are not significantly affected by temperature, species, or season. Seasonal differences in grazing are likely a function of the pelagic community and temperature-dependent metabolism. These results coupled with seasonal hydromedusae abundance data imply summer populations of hydromedusae graze more heavily on prey than winter populations, while also assimilating more carbon into predator tissue. Effects of hydromedusae predation may include modification of trophic structure, shifts in algal community composition, and decline in ecosystem stability, leading to impacts on sustainable commercial fisheries.

Vegetative buffers for fan emissions from poultry farms: 2. ammonia, dust and foliar nitrogen

This study evaluated the potential of trees planted around commercial poultry farms to trap ammonia (NH3) and dust or particulate matter (PM). Norway spruce, Spike hybrid poplar, hybrid willow, and Streamco purpleosier willow were planted on five commercial farms from 2003 to 2004. Plant foliage was sampled in front of the exhaust fans and at a control distance away from the fans on one turkey, two laying hen, and two broiler chicken farms between June and July 2006. Samples were analyzed for dry matter (DM), nitrogen (N), and PM content. In addition, NH3 concentrations were measured downwind of the exhaust fans among the trees and at a control distance using NH3 passive dosi–tubes. Foliage samples were taken and analyzed separately based on plant species. The two layer farms had both spruce and poplar plantings whereas the two broiler farms had hybrid willow and Streamco willow plantings which allowed sampling and species comparisons with the effect of plant location (control vs. fan). The results showed that NH3 concentration h− 1 was reduced by distance from housing fans (P ≤ 0.0001), especially between 0 m (12.01 ppm), 11.4 m (2.59 ppm), 15 m (2.03 ppm), and 30 m (0.31 ppm). Foliar N of plants near the fans was greater than those sampled away from the fans for poplar (3.87 vs. 2.56%; P ≤ 0.0005) and hybrid willow (3.41 vs. 3.02%; P ≤ 0.05). The trends for foliar N in spruce (1.91 vs. 1.77%; P = 0.26) and Streamco willow (3.85 vs. 3.33; P = 0.07) were not significant. Pooling results of the four plant species indicated greater N concentration from foliage sampled near the fans than of that away from the fans (3.27 vs. 2.67%; P ≤ 0.0001). Foliar DM concentration was not affected by plant location, and when pooled the foliar DM of the four plant species near the fans was 51.3% in comparison with 48.5% at a control distance. There was a significant effect of plant location on foliar N and DM on the two layer farms with greater N and DM adjacent to fans than at a control distance (2.95 vs. 2.15% N and 45.4 vs. 38.2% DM, respectively). There were also significant plant species effects on foliar N and DM with poplar retaining greater N (3.22 vs. 1.88%) and DM (43.7 vs. 39.9%) than spruce. The interaction of location by species (P ≤ 0.005) indicated that poplar was more responsive in terms of foliar N, but less responsive for DM than spruce. The effect of location and species on foliar N and DM were not clear among the two willow species on the broiler farms. Plant location had no effect on plant foliar PM weight, but plant species significantly influenced the ability of the plant foliage to trap PM with spruce and hybrid willow showing greater potential than poplar and Streamco willow for PM2.5(0.0054, 0.0054, 0.0005, and 0.0016 mg cm− 2; P ≤ 0.05) and total PM (0.0309, 0.0102, 0.0038, and 0.0046 mg cm− 2, respectively; P ≤ 0.001). Spruce trapped more dust compared to the other three species (hybrid willow, poplar, and Streamco willow) for PM10 (0.0248 vs. 0.0036 mg cm− 2; P ≤ 0.0001) and PM> 10 (0.0033 vs. 0.0003 mg cm− 2; P = 0.052). This study indicates that poplar, hybrid willow, and Streamco willow are appropriate species to absorb poultry house aerial NH3–N, whereas spruce and hybrid willow are effective traps for dust and its associated odors.

Early growth and seasonal chemical composition of three indigenous multipurpose tree species (MPTS) in Abeokuta, Nigeria

A study was carried out to evaluate the growth parameters and nutritive qualities of Moringa oleifera, Millettia griffoniana and Pterocarpus santalinoides. The main objective of the study was to assess the potential of the MPTS in supplementing the feed of ruminant animals during the dry season when grasses are scarce and their quality generally fall short of animal requirements. Leaf samples were randomly collected from the trees for estimation of the proximate composition, neutral detergent fibre, acid detergent fibre and gas production using the in vitro technique. Samples were collected three times to represent seasonal variations as follows: November: Early Dry; February: Mid Dry and April: Late Dry seasons. Gas production was recorded at 3, 6, 9, 12, 15, 18, 21, 24, 48, 72 and 96 h of incubation. Mortality rate was less than 5%. M. oleifera recorded the best overall growth respectively followed by P. santalinoides and M. griffoniana. P. santalinoides and M. oleifera retained more leaves in the dry season than M. griffoniana. The dry matter (DM) and ether extract (EE) contents of the MPTS were significantly (P < 0.05) affected by seasons and plant species while there were significant (P < 0.05) species effects on the CP and ADF values. The gas production values and the fermentation parameters indicated the presence of potentially degradable nutrients in the MPTS, which underscores the importance of the tree species as sources of nutrient for ruminant animals during the dry season.

Cure chemistry of wood/polymeric isocyanate (PMDI) bonds: Effect of wood species

The wood-species dependent performance of polymeric isocyanate resin (PMDI) was investigated by fracture analysis and solid-state NMR. The fracture performance of two different woods (yellow-poplar and southern yellow pine) bonded with PMDI was evaluated using mode-I cleavage. The fracture toughness of pine samples was significantly greater than the corresponding yellow-poplar samples. Separately, the cure chemistry of wood/PMDI bondlines was investigated by solid-state NMR with nitrogen-labeled (N 15) resin, and by employing spectral decomposition of the complex resonance arising from protonated nuclei. A small but statistically significant species effect was found in both the cure chemistry and in the proton rotating-frame relaxation for samples cured at lower temperatures. These differences were not found at higher cure temperatures. This suggested that a species effect might arise in the core of commercial wood-based composite panels, where lower cure temperatures are found. Wood acetylation altered the wood-PMDI cure chemistry by reducing the relative signal intensity in the urethane spectral region by 35%. However acetylated wood specimens still exhibited significant N 15 signal in the urethane spectral region. Since little or no urethane was expected from acetylated samples, an unequivocal urethane detection remains elusive, and if it is detected its occurrence was grossly overestimated by the spectral decomposition employed in this work.