Shoot zinc (Zn) concentration varies widely within Brassica oleracea L. and is affected by soil Zn and phosphorus (P) levels

Summary

The low availability of zinc (Zn) in soils and crops affects dietary Zn intake worldwide. This study sought to determine if the natural genetic variation in shoot Zn concentrations ([Zn]shoot) is sufficient to pursue a crop improvement breeding strategy in a leafy vegetable crop. The gene-pool of Brassica oleracea L. was sampled using a large (n = 376) diversity foundation set (DFS), representing almost all species-wide common allelic variation, and 74 commercial varieties (mostly F₁). The DFS genotypes were grown at low and high soil phosphorus (P) levels under glasshouse and field conditions, and also in a Zn-deficient soil, with or without Zn-fertilisation, in a glasshouse. Despite the large variation in [Zn]shoot among genotypes, environment had a profound effect on [Zn]shoot. The heritability of [Zn]shoot was significant, but relatively low, among 90 doubled-haploid (DH) lines from a mapping population. While several quantitative trait loci (QTL) associated with [Zn]shoot occurred on chromosomes C2, C3, C5, C7, and C9, these were generally weak and conditional upon growth conditions. Breeding for [Zn]shoot in B. oleracea is therefore likely to be challenging. Shoot P concentrations increased substantially in all genotypes under low soil Zn conditions. Conversely, only some genotypes had increased [Zn]shoot at low soil P levels. Sufficient natural genetic variation may therefore exist to study some of the interactions between Zn and P nutrition.     

Evaluation of the impact and control of enzootic abortion of ewes

Despite the availability of effective management and treatment strategies, Chlamydia abortus remains the single most frequently diagnosed cause of infectious ovine abortion (enzootic abortion of ewes, EAE) in the UK and one of the most significant causes of lamb mortality world-wide. In 2007, a survey of UK farmers, veterinarians and other farm animal holders was conducted to gather information on their perceptions of the risk of acquiring infection and the management practices employed to control the disease. The survey indicated that the preferred options for controlling EAE are either through vaccination and/or keeping flocks closed. However, further analysis of data indicates that implementation of these strategies does not provide a guarantee of exclusion of disease from flocks and thus further work is required to improve on current intervention strategies.     

Evaluation of the GrazeIn model of grass dry‐matter intake and milk production prediction for dairy cows in temperate grass‐based production systems. 2 – Animal characteristics

This study evaluated the prediction accuracy of grass dry‐matter intake (GDMI) and milk yield predicted by the GrazeIn model using a large database representing 8787 per cow GDMI measurements. In this study, the animal input variables (age, parity, week of lactation, potential peak milk yield, milk fat content, milk protein content, bodyweight, body condition score (BCS), week of conception, BCS at calving and calf birth weight) were investigated. The mean actual GDMI of the database was 15·9 kg DM per cow d^?1 and GrazeIn predicted a mean GDMI for the database of 15·5 kg DM per cow d^?1. The mean bias was ?0·4 kg DM per cow d^?1. GrazeIn predicted GDMI for the total database with an RPE of 15·5% at cow level. The mean actual daily milk yield of the database was 21·3 kg per cow d^?1 and GrazeIn predicted a daily milk yield for the database of 22·2 kg per cow d^?1. The mean bias was +0·9 kg per cow d^?1. GrazeIn predicted milk yield for the total database with an RPE of 16·7% at cow level. From the evaluation, GrazeIn predicted milk yield of all cows in late lactation with a larger level of error than in early and mid‐lactation. This error appears to be due to the persistency of the lactation curve used by the model, which results in a higher predicted milk yield in late lactation compared with the actual milk yield.     

Anti-inflammatory Properties of Orange Juice: Possible Favorable Molecular and Metabolic Effects

The low-grade inflammation has been recognized as the link between adiposity and the risk of chronic metabolic disorders. Thus, increased concentrations of inflammatory markers, such as interleukins and tumor necrosis factor alpha have been found in obese individuals. In turn, diet can positively or negatively influence on the risk of chronic metabolic diseases by modulating the inflammatory status. In this context, orange juice consumption can play a role in modulation of inflammatory markers through bioactive compounds, such as the flavonoids (hesperidin, naringenin). According to this review, orange juice appears to mediate the inflammatory response in plasma level and gene expression, and in postprandial and chronic (≥7 consecutive days) periods. The current findings suggest that orange juice could be a dietary feature for prevention and treatment of chronic diseases, although more studies are necessary to evaluate the physiological and molecular mechanisms involved.     

Seasonal habitat use of alligator gar in a river–floodplain ecosystem at multiple spatial scales

Alligator gar (Atractosteus spatula) populations are declining throughout their range in the United States, even where considered stable. Similar declines in other riverine species are occurring worldwide due to alteration of habitat in river–floodplain systems. Most rivers in the world are highly regulated, resulting in departures from historic hydrology that provides connection to the floodplain habitats used by riverine fishes. Knowledge of the seasonal habitat requirements of alligator gar and similar riverine fishes at a watershed scale is limited, hindering management practices. We used radiotelemetry to monitor movements and habitat use of adult alligator gar (N = 32; 25.0–84.5 kg; 149–224 cm) at macro‐ and microhabitat scales during 2 years of varying hydrology. Fish showed seasonal differences in their use of main channel and floodplain macrohabitats. Floodplain tributaries and their upper reaches were especially important to reproductive ecology. Minimum distance travelled per day varied seasonally. While using the main channel Fourche LaFave River, gar selected low velocity, shallow depth and complex structure along channel margins. The Fourche LaFave River is unique in its connection to floodplain habitats on a relatively predictable basis, with frequent flooding during the spring and summer reproductive period. Our study emphasises the importance of connectivity between the main river channel and floodplain habitats to a floodplain‐obligate riverine species. An intact, heterogeneous riparian zone creates essential microhabitat for the species. Understanding habitat requirements of alligator gar at multiple spatial scales in a river–floodplain system is crucial to management of many other species and river systems.     

Single versus multiple releases of predatory mites combined with spinosad for the management of western flower thrips in strawberry

Western flower thrips, Frankliniella occidentalis (Pergande), is a major pest of strawberry and other horticultural and ornamental crops. Biological control of F. occidentalis with predatory mites is recommended as an additional management strategy to chemical control in glasshouse and protected crops. However, it is not known whether multiple (two or three) species releases of predatory mites are more effective than single species releases. The effect of an application of spinosad followed by mite releases could further increase suppression of F. occidentalis. In a series of trials in the glasshouse, we evaluated three commercially available predatory mite species, Typhlodromips montdorensis (Schicha), Neoseiulus cucumeris (Oudemans) and Hypoaspis miles (Berlese). Strawberry plants were sprayed once with either spinosad at the recommended rate or with water. F. occidentalis adults were released onto plants 24 h after spraying, and mites were released six days later. Spinosad significantly reduced F. occidentalis compared to the control (water). T. montdorensis, N. cucumeris and H. miles significantly reduced F. occidentalis compared to the ‘no mite’ treatment. Spinosad had no effect on T. montdorensis and N. cucumeris, as their numbers did not differ between the spinosad and control treatments; H. miles was not recovered. When mites were released after an application of spinosad, greater suppression of F. occidentalis was achieved than with releases of predatory mites alone. When released as a double species combination, ‘T. montdorensis and H. miles’ was the most effective combination. There was no difference in efficacy between releases of ‘T. montdorensis and H. miles’ or ‘T. montdorensis, N. cucumeris and H. miles’. We conclude that multiple species releases are more effective than single species releases, and that biological control of F. occidentalis with predatory mites can be used together with spinosad.     

Chain length of cereal fructans isolated from wheat stem and barley grain modulates in vitro fermentation

It is well established that inulin-type fructans, such as oligofructose derived from chicory root, improve gastrointestinal health via fermentation and proliferation of desirable bacteria in the large bowel. However, differences in fructan structure may contribute significantly to different fermentation and subsequent metabolic effects. Here we ascertain the chain length of two novel cereal fructans (graminan) isolated from wheat stem and barley grain, and investigate their fermentation capacity in vitro, in comparison to inulin and oligofructose. Fractions, representing three predominant fructo-oligosaccharide (FOS) size ranges from each source, were fermented and short chain fatty acids (SCFA) production was measured after 24 h of batch culture. Graminan FOS when fermented produced similar levels of total SCFA as oligofructose and inulin. The fermentation of high DP FOS fractions of barley grain and wheat stem (DP 5–15) produced more propionate than oligofructose. Graminan fructans may provide a useful alternative source of oligofructose with potential additional health benefits.     

Movement behavior explains genetic differentiation in American black bears

Individual-based landscape genetic analyses provide empirically based models of gene flow. It would be valuable to verify the predictions of these models using independent data of a different type. Analyses using different data sources that produce consistent results provide strong support for the generality of the findings. Mating and dispersal movements are the mechanisms through which gene flow operates in animal populations. The best means to verify landscape genetic predictions would be to use movement data to independently predict landscape resistance. We used path-level, conditional logistic regression to predict landscape resistance for American black bear (Ursus americanus) in a landscape in which previous work predicted population connectivity using individual-based landscape genetics. We found consistent landscape factors influence genetic differentiation and movement path selection, with strong similarities between the predicted landscape resistance surfaces. Genetic differentiation in American black bear is driven by spring movement (mating and dispersal) in relation to residential development, roads, elevation and forest cover. Given the limited periods of the year when gene flow events primarily occur, models of landscape connectivity should carefully consider temporal changes in functional landscape resistance.