Poor maternal nutrition inhibits muscle development in ovine offspring

Background

Maternal over and restricted nutrition has negative consequences on the muscle of offspring by reducing muscle fiber number and altering regulators of muscle growth. To determine if over and restricted maternal nutrition affected muscle growth and gene and protein expression in offspring, 36 pregnant ewes were fed 60%, 100% or 140% of National Research Council requirements from d 31 ± 1.3 of gestation until parturition. Lambs from control-fed (CON), restricted-fed (RES) or over-fed (OVER) ewes were necropsied within 1 d of birth (n = 18) or maintained on a control diet for 3 mo (n = 15). Semitendinosus muscle was collected for immunohistochemistry, and protein and gene expression analysis.

Results

Compared with CON, muscle fiber cross-sectional area (CSA) increased in RES (58%) and OVER (47%) lambs at 1 d of age (P < 0.01); however at 3 mo, CSA decreased 15% and 17% compared with CON, respectively (P < 0.01). Compared with CON, muscle lipid content was increased in OVER (212.4%) and RES (92.5%) at d 1 (P < 0.0001). Muscle lipid content was increased 36.1% in OVER and decreased 23.6% in RES compared with CON at 3 mo (P < 0.0001). At d 1, myostatin mRNA abundance in whole muscle tended to be greater in OVER (P = 0.07) than CON. Follistatin mRNA abundance increased in OVER (P = 0.04) and tended to increase in RES (P = 0.06) compared with CON at d 1. However, there was no difference in myostatin or follistatin protein expression (P > 0.3). Phosphorylated Akt (ser473) was increased in RES at 3 mo compared with CON (P = 0.006).

Conclusions

In conclusion, maternal over and restricted nutrient intake alters muscle lipid content and growth of offspring, possibly through altered gene and protein expression.     

Growth and nutrient accumulation of Brazil nut trees (Bertholletia excelsa) in agroforestry at different fertilizer levels

The Brazil nut tree(Bertholletia excelsa) is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple uses.We investigated the aboveground biomass production(kg dry weight),nutrient uptake and requirements(N,P,Ca,Mg,K) of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different levels.Eight of 70 experimental trees with different size were harvested and stem,branches and leaves were separated.Nutrient contents were determined for three trees of varying size.Average tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important species.The trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high demand.In contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading crowns.To improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are recommended.These measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.     

Temporal variability of the Atlantic meridional overturning circulation at 26.5 degrees N

The vigor of Atlantic meridional overturning circulation (MOC) is thought to be vulnerable to global warming, but its short-term temporal variability is unknown so changes inferred from sparse observations on the decadal time scale of recent climate change are uncertain. We combine continuous measurements of the MOC (beginning in 2004) using the purposefully designed transatlantic Rapid Climate Change array of moored instruments deployed along 26.5 degrees N, with time series of Gulf Stream transport and surface-layer Ekman transport to quantify its intra-annual variability. The year-long average overturning is 18.7 +/- 5.6 sverdrups (Sv) (range: 4.0 to 34.9 Sv, where 1 Sv = a flow of ocean water of 10(6) cubic meters per second). Interannual changes in the overturning can be monitored with a resolution of 1.5 Sv.     

Eco‐efficiency as a strategy for optimizing the sustainability of pest management

Agricultural industrialization and the subsequent reliance on pesticides has resulted in numerous unintended consequences, such as impacts upon the environment and by extension human health. Eco‐efficiency is a strategy for sustainably increasing production, while simultaneously decreasing these externalities on ecological systems. Eco‐efficiency is defined as the ratio of production to environmental impacts. It has been widely adopted to improve chemical production, but we investigate the challenges of applying eco‐efficiency to pesticide use. Eco‐efficiency strategies include technological innovation, investment in research and development, improvement of business processes, and accounting for market forces. These components are often part of integrated pest management (IPM) systems that include alternatives to pesticides, but its implementation is often thwarted by commercial realities and technical challenges. We propose the creation and adoption of an eco‐efficiency index for pesticide use so that the broad benefits of eco‐efficient strategies such as IPM can be more readily quantified. We propose an index based upon the ratio of crop yield to a risk quotient (RQ) calculated from pesticide toxicity. Eco‐efficiency is an operational basis for optimizing pest management for sustainability. It naturally favors adoption of IPM and should be considered by regulators, researchers, and practitioners involved in pest management. © 2019 Society of Chemical Industry     

Cover Image,Volume 73, Issue 11

The cover image, by Nicola K Richards et al., is based on the Research Article Genetic variation within species and haplotypes of the Wiseana (Lepidoptera: Hepialidae) complex and development of non‐sequenced based identification tools to aid field studies, DOI: 10.1002/ps.4620 . Photo Credit: Colin M. Ferguson, AgResearch‐ Invermay.