Stikstof- en fosforexcretie van varkens, pluimvee en rundvee in biologische en gangbare houderijsystemen

In dit werkdocument is op verzoek van het Ministerie van Economische Zaken de excretie van stikstof (N) en fosfor (P) van gangbaar en biologisch gehouden varkens, pluimvee en melkkoeien vergeleken.Ten opzichte van gangbaar gehouden dieren zijn de berekende N- en P-excretie per dier per jaar circa 25% hoger bij biologisch gehouden vleesvarkens en respectievelijk circa 60 en 75% hoger voor biologisch gehouden zeugen met bijbehorende biggen. De N- en P-excretie per dier per jaar van biologisch gehouden leghennen zijn respectievelijk 22 en 17% hoger dan in gangbare scharrelsystemen en 35 en 26% hoger dan in gangbare verrijkte kooi / kolonie gehouden leghennen. De N- en P-excretie per vleeskuikenplaats per jaar van biologisch gehouden vleeskuikens zijn in vergelijking met gangbaar gehouden vleeskuikens respectievelijk 62 en 105% hoger.De berekende N- en P-excretie per melkkoe per jaar is bij biologisch gehouden melkvee circa 12% lager dan bij gangbaar gehouden melkvee. De verschillen in excretie tussen gangbaar en biologisch gehouden pluimvee en varkens worden vooral veroorzaakt door de hogere voerconversie en de hogere N- en P-gehalten in het voer bij biologisch gehouden dieren. Bij melkvee is de lagere productie van biologische gehouden dieren van groter gewicht

Streamlining Sporozoite Isolation From Mosquitoes by Leveraging the Dynamics of Migration to the Salivary Glands

Background: Sporozoites isolated from the salivary glands of Plasmodium-infected mosquitoes are a prerequisite for several basic and pre-clinical applications. Although salivary glands are pooled to maximize sporozoite recovery, insufficient yields pose logistical and analytical hurdles; thus, predicting yields prior to isolation would be valuable. Preceding oocyst densities in the midgut is an obvious candidate. However, it is unclear whether current understanding of its relationship with sporozoite densities can be used to maximize yields, or whether it can capture the potential density-dependence in rates of sporozoite invasion of the salivary glands. Methods: This study presents a retrospective analysis of Anopheles stephensi mosquitoes infected with two strains of the rodent-specific Plasmodium berghei. Mean oocyst densities were estimated in the midguts earlier in the infection (11-15 days post-blood meal), with sporozoites pooled from the salivary glands later in the infection (17-29 days). Generalized linear mixed effects models were used to determine if (1) mean oocyst densities can predict sporozoite yields from pooled salivary glands, (2) whether these densities can capture differences in rates of sporozoite invasion of salivary glands, and (3), if the interaction between oocyst densities and time could be leveraged to boost overall yields. Results: The non-linear effect of mean oocyst densities confirmed the role of density-dependent constraints in limiting yields beyond certain oocyst densities. Irrespective of oocyst densities however, the continued invasion of salivary glands by the sporozoites boosted recoveries over time (17-29 days post-blood meal) for either parasite strain. Conclusions: Sporozoite invasion of the salivary glands over time can be leveraged to maximize yields for P. berghei. In general, however, invasion of the salivary glands over time is a critical fitness determinant for all Plasmodium species (extrinsic incubation period, EIP). Thus, delaying sporozoite collection could, in principle, substantially reduce dissection effort for any parasite within the genus, with the results also alluding to the potential for changes in sporozoites densities over time to modify infectivity for the next host

Women\u27s health: Optimal nutrition throughout the lifecycle

Sex differences are an important consideration when researching and establishing policies for nutrition and optimal health. For women\u27s health, there are important physiologic, neurologic, and hormonal distinctions throughout the lifecycle that impact nutritional needs. Distinct from those for men, these nutritional needs must be translated into appropriate nutrition policy that aims to not only avoid overt nutritional deficiency, but also to promote health and minimize risk for chronic disease. Through a series of webinars, scientific experts discussed the advances in the understanding of the unique nutritional needs, challenges and opportunities of the various life stages for women across the life course and identified emerging nutritional interventions that may be beneficial for women. Nevertheless, there is concern that existing nutrition policy intended for women\u27s health is falling short with examples of programs that are focused more on delivering calories than achieving optimal nutrition. To be locally effective, targeted nutrition needs to offer different proposals for different cultural, socio-economic, and geographic communities, and needs to be applicable at all stages of growth and development. There must be adequate access to nutritious foods, and the information to understand and implement proven nutritional opportunities. Experts provided recommendations for improvement of current entitlement programs that will address accessibility and other social and environmental issues to support women properly throughout the lifecycle

Asian elephants as ecological filters in Sundaic forests

Megaherbivores exert strong top-down influence on the ecosystems they inhabit, yet little is known about the foraging impacts of Asian elephants (Elephas maximus) on the structure of Southeast Asia’s rainforests. Our goal was to document Asian elephants’ dietary composition, selectivity, and foraging impacts in a Sundaic rainforest and test whether these differed between habitats. We conducted controlled direct observations of five wild-born captive elephants feeding on six plant types (bamboo, grass, monocot herbs, palms, lianas, and trees) of different age 2 in two habitats (mature vs. early successional forest) in Krau, Peninsular Malaysia. Palms, trees, and lianas formed the bulk of the elephants’ diet. In the mature forest, elephants showed a strong preference for monocots (preference ratio, PR = 5.1), particularly large palms (PR = 5.4), while trees were negatively selected (PR = 0.14). Conversely, in early successional habitats, large tree saplings were positively selected (PR = 1.6). Elephants uprooted (30%) and broke the main stem (30%) of the dicot trees, mainly large saplings, that they handled. Tree saplings broken by elephants had an average diameter of 1.7 ± 1.1 cm (up to 7 cm), with breaks happening at 1.1 ± 0.5 m of height. We estimated that, in a year, an elephant could damage (i.e., either uproot or break) around 39,000 tree saplings if it fed entirely in mature forest, and almost double the number (73,000) if it fed solely in early successional habitats. Assuming a density of 0.05–0.18 elephants/km2, elephant foraging could damage 0.2–0.6% of the tree sapling population per year. Slow growth rates of understory plants in mature forests could result in negative feedbacks, whereby elephants suppress palms, other monocots, and highly preferred tree species. Alternatively, elephants may initiate positive feedbacks by impeding succession along forest edges and in semi-open environments, thereby increasing the size of gaps and the availability of their preferred foodplants. Overall, our results show that Asian elephants act as ecological filters by suppressing the plants they prefer in Southeast Asia’s rainforests

Asian elephants as ecological filters in Sundaic forests

Megaherbivores exert strong top-down influence on the ecosystems they inhabit, yet little is known about the foraging impacts of Asian elephants (Elephas maximus) on the structure of Southeast Asia’s rainforests. Our goal was to document Asian elephants’ dietary composition, selectivity, and foraging impacts in a Sundaic rainforest and test whether these differed between habitats. We conducted controlled direct observations of five wild-born captive elephants feeding on six plant types (bamboo, grass, monocot herbs, palms, lianas, and trees) of different age 2 in two habitats (mature vs. early successional forest) in Krau, Peninsular Malaysia. Palms, trees, and lianas formed the bulk of the elephants’ diet. In the mature forest, elephants showed a strong preference for monocots (preference ratio, PR = 5.1), particularly large palms (PR = 5.4), while trees were negatively selected (PR = 0.14). Conversely, in early successional habitats, large tree saplings were positively selected (PR = 1.6). Elephants uprooted (30%) and broke the main stem (30%) of the dicot trees, mainly large saplings, that they handled. Tree saplings broken by elephants had an average diameter of 1.7 ± 1.1 cm (up to 7 cm), with breaks happening at 1.1 ± 0.5 m of height. We estimated that, in a year, an elephant could damage (i.e., either uproot or break) around 39,000 tree saplings if it fed entirely in mature forest, and almost double the number (73,000) if it fed solely in early successional habitats. Assuming a density of 0.05–0.18 elephants/km2, elephant foraging could damage 0.2–0.6% of the tree sapling population per year. Slow growth rates of understory plants in mature forests could result in negative feedbacks, whereby elephants suppress palms, other monocots, and highly preferred tree species. Alternatively, elephants may initiate positive feedbacks by impeding succession along forest edges and in semi-open environments, thereby increasing the size of gaps and the availability of their preferred foodplants. Overall, our results show that Asian elephants act as ecological filters by suppressing the plants they prefer in Southeast Asia’s rainforests

Deconvolving molecular signatures of interactions between microbial colonies

Motivation: The interactions between microbial colonies through chemical signaling are not well understood. A microbial colony can use different molecules to inhibit or accelerate the growth of other colonies. A better understanding of the molecules involved in these interactions could lead to advancements in health and medicine. Imaging mass spectrometry (IMS) applied to co-cultured microbial communities aims to capture the spatial characteristics of the colonies’ molecular fingerprints. These data are high-dimensional and require computational analysis methods to interpret