Records 1 - 20 / 1681
Relative brain size is predicted by the intensity of intrasexual competition in frogs
Mai, Chun Lan ; Liao, Wen Bo ; Lüpold, Stefan ; Kotrschal, Alexander - \ 2020
American Naturalist 196 (2020)2. - ISSN 0003-0147 - p. 169 - 179.
Anurans - Cognitive abilities - Male-male competition - Operational sex ratio - Spawning-site group size
Competition over mates is a powerful force shaping trait evolution. For instance, better cognitive abilities may be beneficial in male-male competition and thus be selected for by intrasexual selection. Alternatively, investment in physical attributes favoring male performance in competition for mates may lower the resources available for brain development, and more intense male mate competition would coincide with smaller brains. To date, only indirect evidence for such relationships exists, and most studies are heavily biased toward primates and other homoeothermic vertebrates. We tested the association between male brain size (relative to body size) and male-male competition across N = 30 species of Chinese anurans. Three indicators of the intensity of male mate competition—operational sex ratio (OSR), spawningsite density, and male forelimb muscle mass—were positively associated with relative brain size, whereas the absolute spawning group size was not. The relationship with the OSR and male forelimb muscle mass was stronger for the male than for the female brains. Taken together, our findings suggest that the increased cognitive abilities of larger brains are beneficial in male-male competition. This study adds taxonomic breadth to the mounting evidence for a prominent role of sexual selection in vertebrate brain evolution.
Live Imaging of embryogenic structures in Brassica napus microspore embryo cultures highlights the developmental plasticity of induced totipotent cells
Corral-Martínez, Patricia ; Siemons, Charlotte ; Horstman, Anneke ; Angenent, Gerco C. ; Ruijter, Norbert de; Boutilier, Kim - \ 2020
Plant Reproduction (2020). - ISSN 2194-7953
Brassica napus - LEAFY COTYLEDON1 - Microspore embryogenesis - Suspensor - Time-lapse imaging - Totipotency
Key message: In vitro embryo development is highly plastic; embryo cell fate can be re-established in tissue culture through 17 different pathways. Abstract: In most angiosperms, embryo development from the single-celled zygote follows a defined pattern of cell divisions in which apical (embryo proper) and basal (root and suspensor) cell fates are established within the first cell divisions. By contrast, embryos that are induced in vitro in the absence of fertilization show a less regular initial cell division pattern yet develop into histodifferentiated embryos that can be converted into seedlings. We used the Brassica napus microspore embryogenesis system, in which the male gametophyte is reprogrammed in vitro to form haploid embryos, to identify the developmental fates of the different types of embryogenic structures found in culture. Using time-lapse imaging of LEAFY COTYLEDON1-expressing cells, we show that embryogenic cell clusters with very different morphologies are able to form haploid embryos. The timing of surrounding pollen wall (exine) rupture is a major determinant of cell fate in these clusters, with early exine rupture leading to the formation of suspensor-bearing embryos and late rupture to suspensorless embryos. In addition, we show that embryogenic callus, which develops into suspensor-bearing embryos, initially expresses transcripts associated with both basal- and apical-embryo cell fates, suggesting that these two cell fates are fixed later in development. This study reveals the inherent plasticity of in vitro embryo development and identifies new pathways by which embryo cell fate can be established.
Social paper wasp (Agelaia pallipes) predates songbird nestling
Frankhuizen, Sjoerd ; Esteves Lopes, Leonardo ; Cunha, Filipe C.R. - \ 2020
Ethology (2020). - ISSN 0179-1613
Agelaia pallipes - insect predator - nest predation - Sporophila lineola
The social paper wasp Agelaia pallipes is known to eat carrion and scavenge on vertebrates. There are few records of wasps predating vertebrates, including an attack on an adult hummingbird and the predation of bird nestlings. During a project monitoring reproductive behaviour of a neotropical songbird, the Lined Seedeater Sporophila lineola in south-eastern Brazil, we recorded the predation of a four-day-old nestling by a social paper wasp. In the video, the adult female bird attempted to visit the nest prior to the predation. The male could be seen with its crest feathers erect after a wasp left the nest, when the nestling was presumably already dead. When we arrived at the nest to remove the camera, we found the nestling dead, and did not observe the parents in the vicinity. We also registered two other dead nestlings in a different nest with similar wounds. However, the conclusive cause of death of those nestlings is unknown. Nest predation is a major selective pressure in birds, and insects are rarely assumed to play a notable role in this process. Further research is needed to better understand the nature of the relationship between wasps and birds.
Omega-3 phospholipids from krill oil enhance intestinal fatty acid oxidation more effectively than omega-3 triacylglycerols in high-fat diet-fed obese mice
Kroupova, Petra ; Schothorst, Evert M. van; Keijer, Jaap ; Bunschoten, Annelies ; Vodicka, Martin ; Irodenko, Ilaria ; Oseeva, Marina ; Zacek, Petr ; Kopecky, Jan ; Rossmeisl, Martin ; Horakova, Olga - \ 2020
Nutrients 12 (2020)7. - ISSN 2072-6643 - 20 p.
High-fat diet - Krill oil - Omega-3 index - Omega-3 phospholipids - Small intestine
Antisteatotic effects of omega-3 fatty acids (Omega-3) in obese rodents seem to vary depending on the lipid form of their administration. Whether these effects could reflect changes in intestinal metabolism is unknown. Here, we compare Omega-3-containing phospholipids (krill oil; ω3PL-H) and triacylglycerols (ω3TG) in terms of their effects on morphology, gene expression and fatty acid (FA) oxidation in the small intestine. Male C57BL/6N mice were fed for 8 weeks with a high-fat diet (HFD) alone or supplemented with 30 mg/g diet of ω3TG or ω3PL-H. Omega-3 index, reflecting the bioavailability of Omega-3, reached 12.5% and 7.5% in the ω3PL-H and ω3TG groups, respectively. Compared to HFD mice, ω3PL-H but not ω3TG animals had lower body weight gain (−40%), mesenteric adipose tissue (−43%), and hepatic lipid content (−64%). The highest number and expression level of regulated intestinal genes was observed in ω3PL-H mice. The expression of FA ω-oxidation genes was enhanced in both Omega-3-supplemented groups, but gene expression within the FA β-oxidation pathway and functional palmitate oxidation in the proximal ileum was significantly increased only in ω3PL-H mice. In conclusion, enhanced intestinal FA oxidation could contribute to the strong antisteatotic effects of Omega-3 when administered as phospholipids to dietary obese mice.
Do Locals Have a Say? Community Experiences of Participation in Governing Forest Plantations in Tanzania
Degnet, M.B. ; Werf, E. van der; Ingram, V.J. ; Wesseler, J.H.H. - \ 2020
Forests 11 (2020)7. - ISSN 1999-4907
As large-scale forest plantations expand in developing countries, concerns are rising about their relation to and integration with adjacent local communities. In developing countries with weak enforcement of property rights, private plantations are more likely than state-owned plantations to involve villagers in plantation’s activities in order to secure and guarantee their access to land and labor resources. Certification standards of the Forest Stewardship Council (FSC) and adherence to responsible investment guidelines further strengthen this likelihood by requiring plantations to consult and engage local communities. Using household data from Tanzania, we assess households’ experiences with their participation in plantation activities by comparing the experiences of households in villages adjacent to private, FSC-certified plantations with those of households in villages adjacent to a non-certified, state-owned plantation. Our quantitative analyses show that households in the villages adjacent to the private, certified plantations are more likely to report to participate in plantation activities. Our results show that the certified plantations are more likely to respond to community complaints and grievances. We further find that male-headed households and households of plantation employees are more likely than female-headed households and households without plantation employees to participate in plantations’ activities. Our results imply that forest management certification can complement state policy approaches of sustainable forest management to enhance community participation in forest management
Self-reports of Dutch dog owners on received professional advice, their opinions on castration and behavioural reasons for castrating male dogs
Roulaux, Pascalle E.M. ; Herwijnen, Ineke R. van; Beerda, Bonne - \ 2020
PLoS ONE 15 (2020)6. - ISSN 1932-6203
Male dogs are often castrated based on the thought that it facilitates well-behavedness. However, the causal evidence for this from prospective studies lacks and the existing associative studies present mixed results depending on the studied behaviours. We aimed to gain insight into possible factors driving an owner's decision to castrate their male dog, through a quantitative survey based on a convenience sample. We determined the advice owners received from three types of dog professionals (veterinarian practitioners, behavioural trainers, behavioural therapists) and the owners' assessments of castration's behavioural effects. Data on 491 Dutch owners of castrated and intact male dogs were analysed with Chi-square tests. Results indicate that owners of both castrated and intact dogs received castration advice most often from veterinarian practitioners, with pro-castration at higher frequencies for owners of castrated dogs (Chi-square, P<0.001). Overall, most owners disagreed with or were neutral about statements on castration positively affecting male dog behaviour at a population level. Nevertheless, 58% (N = 145) of the owners of castrated dogs (N = 249) reported that correcting unwanted behaviour was a reason to castrate their own male dog. Unwanted behaviour involved aggression in 50% (N = 70) of the owner-dog dyads. Castrated dog's aggression changes were reported on most as 'no change'. The second most common answer indicated an aggression decrease in dogs castrated to correct unwanted behaviour and an increase in dogs castrated for other reasons (Chi-square, P<0.001). The increase in aggression in a subset of castrated dogs is concerning, as aggression can pose risks to the dog's welfare. We acknowledge the limitations of our study which identifies associations rather than provides causal evidence. Still, we recommend professionals' awareness of possible negative behavioural changes following castration, like increased aggression. Future research on behavioural consequences of castrating dogs needs to build a more solid knowledge base for balanced advice regarding castration.
Birth weight affects body protein retention but not nitrogen efficiency in the later life of pigs
Peet-Schwering, Carola M.C. van der; Verschuren, Lisanne M.G. ; Hedemann, Mette S. ; Binnendijk, Gisabeth P. ; Jansman, Alfons J.M. - \ 2020
Journal of Animal Science 98 (2020)6. - ISSN 0021-8812
birth weight - growing pigs - nitrogen efficiency - nitrogen retention - nontargeted metabolomics
Exploring factors that might affect nitrogen (N) efficiency in pigs could support the development of precision feeding concepts. Therefore, an experiment was conducted to determine the effects of birth weight (BiW) on N retention, N efficiency, and concentrations of metabolites in plasma and urine related to N efficiency in male pigs of 14 wk of age. BiW of the low BiW (LBW) and high BiW (HBW) pigs was 1.11 ± 0.14 and 1.79 ± 0.12 kg, respectively. Twenty LBW and 20 HBW pigs were individually housed in metabolism cages and were subjected to an N balance study in two sequential periods of 5 d, after an 11-d adaptation period. Pigs were assigned to a protein adequate (A) or protein restricted (R, 70% of A) regime in a change-over design and fed restrictedly 2.8 times the energy requirements for maintenance. Nontargeted metabolomics analyses were performed in urine and blood plasma samples. The N retention in g/d was higher in the HBW than in the LBW pigs (P < 0.001). The N retention in g/(kg BW0.75·d) and N efficiency (= 100% × N retention / N intake), however, were not affected by BiW of the pigs. Moreover, fecal digestibility of N and urinary concentration of N and urea were not affected by BiW of the pigs. The concentration of insulin (P = 0.08) and insulin-like growth factor-1 (IGF-1;P = 0.05) in blood plasma was higher in HBW pigs, whereas the concentration of α-amino N tended to be lower in HBW pigs (P = 0.06). The LBW and HBW pigs could not be discriminated based on the plasma and urinary metabolites retrieved by nontargeted metabolomics. Restricting dietary protein supply decreased N retention (P < 0.001), N efficiency (P = 0.07), fecal N digestibility (P < 0.001), urinary concentration of N and urea (P < 0.001), and concentration of urea (P < 0.001), IGF-1 (P < 0.001), and α-amino N (P < 0.001) in blood plasma. The plasma and urinary metabolites differing between dietary protein regime were mostly amino acids (AA) or their derivatives, metabolites of the tricarboxylic acid cycle, and glucuronidated compounds, almost all being higher in the pigs fed the A regime. This study shows that BiW affects absolute N retention but does not affect N efficiency in growing pigs. Therefore, in precision feeding concepts, BiW of pigs should be considered as a factor determining protein deposition capacity but less as a trait determining N efficiency.
Identification of blood cell transcriptome-based biomarkers in adulthood predictive of increased risk to develop metabolic disorders using early life intervention rat models
Szostaczuk, Nara ; Schothorst, Evert M. van; Sánchez, Juana ; Priego, Teresa ; Palou, Mariona ; Bekkenkamp-Grovenstein, Melissa ; Faustmann, Gernot ; Obermayer-Pietsch, Barbara ; Tiran, Beate ; Roob, Johannes M. ; Winklhofer-Roob, Brigitte M. ; Keijer, Jaap ; Palou, Andreu ; Picó, Catalina - \ 2020
FASEB Journal 34 (2020)7. - ISSN 0892-6638 - p. 9003 - 9017.
gestational calorie restriction - metabolic health - metabolic programing - NPC1 - PBMCs - predictive biomarkers
Calorie restriction during gestation in rats has long-lasting adverse effects in the offspring. It induces metabolic syndrome-related alterations, which are partially reversed by leptin supplementation during lactation. We employed these conditions to identify transcript-based nutrient sensitive biomarkers in peripheral blood mononuclear cells (PBMCs) predictive of later adverse metabolic health. The best candidate was validated in humans. Transcriptome analysis of PBMCs from adult male Wistar rats of three experimental groups was performed: offspring of control dams (CON), and offspring of 20% calorie-restricted dams during gestation without (CR) and with leptin supplementation throughout lactation (CR-LEP). The expression of 401 genes was affected by gestational calorie restriction and reversed by leptin. The changes preceded metabolic syndrome-related phenotypic alterations. Of these genes, Npc1 mRNA levels were lower in CR vs CON, and normalized to CON in CR-LEP. In humans, NPC1 mRNA levels in peripheral blood cells (PBCs) were decreased in subjects with mildly impaired metabolic health compared to healthy subjects. Therefore, a set of potential transcript-based biomarkers indicative of a predisposition to metabolic syndrome-related alterations were identified, including NPC1, which was validated in humans. Low NPC1 transcript levels in PBCs are a candidate biomarker of increased risk for impaired metabolic health in humans.
Poverty or prosperity in northern India? New evidence on real wages, 1590s–1870s†
Zwart, Pim de; Lucassen, Jan - \ 2020
Economic History Review 73 (2020)3. - ISSN 0013-0117 - p. 644 - 667.
This article introduces a new dataset on wages in northern India (from Gujarat in the west to Bengal in the east) from the 1590s to the 1870s. It follows Allen's subsistence basket methodology to compute internationally comparable real wages to shed light on developments in Indian living standards over time. It adjusts the comparative cost-of-living indices to take into account differences in climate and caloric intake due to variances in heights. The article also discusses the male/female wage gap in northern India. It demonstrates that the ‘great divergence’ started in the late seventeenth century, and widened further after the 1720s and especially after the 1800s. It was subsequently primarily England's spurt and India's stagnation in the first half of the nineteenth century that brought about most serious differences in the standard of living. If the British colonial state is to blame—as often suggested by the literature on India's persistent poverty—the fault lies in its failure to improve the situation after the British became near-undisputed masters of India in 1820.
Dynamics of Intersexual Dominance and Adult Sex- Ratio in Wild Vervet Monkeys
Hemelrijk, Charlotte Korinna ; Wubs, Matthias ; Gort, Gerrit ; Botting, Jennifer ; Waal, Erica van de - \ 2020
Frontiers in Psychology 11 (2020). - ISSN 1664-1078
adult sex-ratio - dominance hierarchy - female dominance over males - fierceness of aggression - the winner-loser effect - vervet monkeys
Intersexual dominance relations are important for female mammals, because of their consequences for accessing food and for the degree of sexual control females experience from males. Female mammals are usually considered to rank below males in the dominance hierarchy, because of their typical physical inferiority. Yet, in some groups or species, females are nonetheless dominant over some males (partial female dominance). Intersexual dominance, therefore, also depends on traits other than sexual dimorphism, such as social support, social exchange, group adult sex-ratio, and the widespread self-reinforcing effects of winning and losing fights, the “winner-loser effect.” The importance of sex-ratio and the winner-loser effect remains poorly understood. A theoretical model, DomWorld, predicts that in groups with a higher proportion of males, females are dominant over more males when aggression is fierce (not mild). The model is based on a small number of general processes in mammals, such as grouping, aggression, the winner-loser effect, the initially greater fighting capacity of males than females, and sex ratio. We expect its predictions to be general and suggest they be examined in a great number of species and taxa. Here, we test these predictions in four groups of wild vervet monkeys (Chlorocebus pygerythrus) in Mawana game reserve in Africa, using 7 years of data. We confirm that a higher proportion of males in the group is associated with greater dominance of females over males; a result that remains when combining these data with those of two other sites (Amboseli and Samara). We additionally confirm that in groups with a higher fraction of males there is a relatively higher (a) proportion of fights of males with other males, and (b) proportion of fights won by females against males from the fights of females with any adults. We reject alternative hypotheses that more dominance of females over males could be attributed to females receiving more coalitions from males, or females receiving lowered male aggression in exchange for sexual access (the docile male hypothesis). We conclude that female dominance relative to males is dynamic and that future empirical studies of inter-sexual dominance will benefit by considering the adult sex-ratio of groups.
Effects of eggshell temperature pattern during incubation on tibia characteristics of broiler chickens at slaughter age
Güz, B.C. ; Molenaar, R. ; Jong, I.C. de; Kemp, B. ; Krimpen, M. van; Brand, H. van den - \ 2020
Poultry Science 99 (2020)6. - ISSN 0032-5791 - p. 3020 - 3029.
broiler chickens - eggshell temperature - incubation - leg health - tibia
This study was designed to determine effects of eggshell temperature (EST) pattern in week 2 and week 3 of incubation on tibia development of broiler chickens at slaughter age. A total of 468 Ross 308 eggs were incubated at an EST of 37.8°C from incubation day (E) 0 to E7. Thereafter, a 2 × 2 factorial arrangement with 2 EST (37.8°C and 38.9°C) from E8 to E14 and 2 EST (36.7°C and 37.8°C) from E15 till hatch was applied. After hatching, chickens were reared until slaughter age with the 4 EST treatments and 8 replicates per treatment. At day 41 and 42, one male chicken per replicate per day was selected, and hock burn and food pad dermatitis were scored. Rotated tibia, tibia dyschondroplasia, epiphyseal plate abnormalities, bacterial chondronecrosis with osteomyelitis, and epiphysiolysis were assessed. Tibia weight, length, thickness, head thickness, and robusticity index were determined. X-ray analyses (osseous volume, pore volume, total volume, volume fraction, mineral content, and mineral density) and a 3-point bending test (ultimate strength, yield strength, stiffness, energy to fracture, and elastic modulus) were performed. A high EST (38.9°C) in week 2 of incubation, followed by a normal EST (37.8°C) in week 3 resulted in higher mineral content (P = 0.001), mineral density (P = 0.002), ultimate strength (P = 0.04), yield strength (P = 0.03), and stiffness (P = 0.05) compared with the other 3 EST groups (week 2 × week 3 interaction). A high EST (38.9°C) in week 2 of incubation, regardless of the EST in week 3, resulted in a higher tibia weight (P < 0.001), thickness (P = 0.05), osseous volume (P < 0.001), and total volume (P < 0.001) than a normal EST (37.8°C). It can be concluded that 1.1°C higher EST than normal in week 2 of incubation appears to stimulate tibia morphological, biophysical, and mechanical characteristics of broiler chickens at slaughter age. Additionally, a 1.1°C lower EST in week 3 of incubation appears to have negative effects on tibia characteristics, particularly in interaction with the EST in week 2 of incubation.
Deep learning for automated detection of Drosophila suzukii : potential for UAV-based monitoring
Roosjen, Peter P.J. ; Kellenberger, Benjamin ; Kooistra, Lammert ; Green, David R. ; Fahrentrapp, Johannes - \ 2020
Pest Management Science (2020). - ISSN 1526-498X
deep learning - Drosophila suzukii - integrated pest management (IPM) - object detection - unmanned aerial vehicle (UAV)
BACKGROUND: The fruit fly Drosophila suzukii, or spotted wing drosophila (SWD), is a serious pest worldwide, attacking many soft-skinned fruits. An efficient monitoring system that identifies and counts SWD in crops and their surroundings is therefore essential for integrated pest management (IPM) strategies. Existing methods, such as catching flies in liquid bait traps and counting them manually, are costly, time-consuming and labour-intensive. To overcome these limitations, we studied insect trap monitoring using image-based object detection with deep learning. RESULTS: Based on an image database with 4753 annotated SWD flies, we trained a ResNet-18-based deep convolutional neural network to detect and count SWD, including sex prediction and discrimination. The results show that SWD can be detected with an area under the precision recall curve (AUC) of 0.506 (female) and 0.603 (male) in digital images taken from a static position. For images collected using an unmanned aerial vehicle (UAV), the algorithm detected SWD individuals with an AUC of 0.086 (female) and 0.284 (male). The lower AUC for the aerial imagery was due to lower image quality caused by stabilisation manoeuvres of the UAV during image collection. CONCLUSION: Our results indicate that it is possible to monitor SWD using deep learning and object detection. Moreover, the results demonstrate the potential of UAVs to monitor insect traps, which could be valuable in the development of autonomous insect monitoring systems and IPM.
Involvement of lactate and pyruvate in the anti-inflammatory effects exerted by voluntary activation of the sympathetic nervous system
Zwaag, Jelle ; Horst, Robter ; Blaženovic, Ivana ; Stoessel, Daniel ; Ratter, Jacqueline ; Worseck, Josephine M. ; Schauer, Nicolas ; Stienstra, Rinke ; Netea, Mihai G. ; Jahn, Dieter ; Pickkers, Peter ; Kox, Matthijs - \ 2020
Metabolites 10 (2020)4. - ISSN 2218-1989
We recently demonstrated that the sympathetic nervous system can be voluntarily activated following a training program consisting of cold exposure, breathing exercises, and meditation. This resulted in profound attenuation of the systemic inflammatory response elicited by lipopolysaccharide (LPS) administration. Herein, we assessed whether this training program affects the plasma metabolome and if these changes are linked to the immunomodulatory effects observed. A total of 224 metabolites were identified in plasma obtained from 24 healthy male volunteers at six timepoints, of which 98 were significantly altered following LPS administration. Effects of the training program were most prominent shortly after initiation of the acquired breathing exercises but prior to LPS administration, and point towards increased activation of the Cori cycle. Elevated concentrations of lactate and pyruvate in trained individuals correlated with enhanced levels of anti-inflammatory interleukin (IL)-10. In vitro validation experiments revealed that co-incubation with lactate and pyruvate enhances IL-10 production and attenuates the release of pro-inflammatory IL-1β and IL-6 by LPS-stimulated leukocytes. Our results demonstrate that practicing the breathing exercises acquired during the training program results in increased activity of the Cori cycle. Furthermore, this work uncovers an important role of lactate and pyruvate in the anti-inflammatory phenotype observed in trained subjects.
Gendered species preferences link tree diversity and carbon stocks in Cacao agroforest in Southeast Sulawesi, Indonesia
Sari, Rika Ratna ; Saputra, Danny Dwi ; Hairiah, Kurniatun ; Rozendaal, Danaë M.A. ; Roshetko, James M. ; Noordwijk, Meine Van - \ 2020
Land 9 (2020)4. - ISSN 2073-445X
Cacao agroforestry - Carbon storage - Farmer tree preference - Utility value
The degree to which the maintenance of carbon (C) stocks and tree diversity can be jointly achieved in production landscapes is debated. C stocks in forests are decreased by logging before tree diversity is affected, while C stocks in monoculture tree plantations increase, but diversity does not. Agroforestry can break this hysteresis pattern, relevant for policies in search of synergy. We compared total C stocks and tree diversity among degraded forest, complex cacao/fruit tree agroforests, simple shade-tree cacao agroforestry, monoculture cacao, and annual crops in the Konawe District, Southeast Sulawesi, Indonesia. We evaluated farmer tree preferences and the utility value of the system for 40 farmers (male and female). The highest tree diversity (Shannon-Wiener H index 2.36) and C stocks (282 Mg C ha-1) were found in degraded forest, followed by cacao-based agroforestry systems (H index ranged from 0.58-0.93 with C stocks of 75-89 Mg ha-1). Male farmers selected timber and fruit tree species with economic benefits as shade trees, while female farmers preferred production for household needs (fruit trees and vegetables). Carbon stocks and tree diversity were positively related (R2 = 0.72). Adding data from across Indonesia (n = 102), agroforestry systems had an intermediate position between forest decline and reforestation responses. Maintaining agroforestry in the landscape allows aboveground C stocks up to 50 Mg ha-1 and reduces biodiversity loss. Agroforestry facilitates climate change mitigation and biodiversity goals to be addressed simultaneously in sustainable production landscapes.
Species and sex-specific chemosensory gene expression in Anopheles coluzzii and An. quadriannulatus antennae
Athrey, Giridhar ; Popkin-Hall, Zachary ; Cosme, Luciano Veiga ; Takken, Willem ; Slotman, Michel Andre - \ 2020
Parasites & Vectors 13 (2020)1. - ISSN 1756-3305
Anopheles - Chemosensation - Host seeking - Mating - Olfaction
Background: Olfactory cues drive mosquito behaviors such as host-seeking, locating sugar sources and oviposition. These behaviors can vary between sexes and closely related species. For example, the malaria vector Anopheles coluzzii is highly anthropophilic, whereas An. quadriannulatus is not. These behavioral differences may be reflected in chemosensory gene expression. Methods: The expression of chemosensory genes in the antennae of both sexes of An. coluzzii and An. quadriannulatus was compared using RNA-seq. The sex-biased expression of several genes in An. coluzzii was also compared using qPCR. Results: The chemosensory expression is mostly similar in the male antennae of An. coluzzii and An. quadriannulatus, with only a few modest differences in expression. A handful of chemosensory genes are male-biased in both species; the highly expressed gustatory receptor AgGr33, odorant binding proteins AgObp25, AgObp26 and possibly AgObp10. Although the chemosensory gene repertoire is mostly shared between the sexes, several highly female-biased AgOrs, AgIrs, and one AgObp were identified, including several whose expression is biased towards the anthropophilic An. coluzzii. Additionally, the expression of several chemosensory genes is biased towards An. coluzzii in both sexes. Conclusions: Chemosensory gene expression is broadly similar between species and sexes, but several sex- biased/specific genes were identified. These may modulate sex- and species-specific behaviors. Although the male behavior of these species remains poorly studied, the identification of sex- and species-specific chemosensory genes may provide fertile ground for future work.[Figure not available: see fulltext.]
Amino acid and energy requirements of growing-finishing pigs kept under low and high sanitary conditions
Peet-Schwering, C.M.C. van der; Verheijen, R.G.J.A. ; Binnendijk, G.P. ; Jansman, A.J.M. - \ 2020
Wageningen : Wageningen Livestock Research (Wageningen Livestock Research report 1248) - 51
The present study was performed to evaluate the effects of dietary energy source (starch vs fat) and of increased levels of dietary energy and essential amino acids (EAA), related to the assumed increased EAA and energy requirements in immune stimulated pigs, on the growth performance of growing-finishing (GF) pigs under low sanitary conditions (LSC), in which the immune system of the pigs was activated, or under high sanitary conditions (HSC) resulting in a lower state of activation of the immune system. The trial was conducted with 408 male pigs (Tempo boar x (York x Dutch Landrace) sow) during the weaner, grower and finisher phase. Piglets were weaned at an age of four weeks and followed till delivery to the slaughterhouse. In a 2 × 2 × 2 factorial design, pigs were allocated to either high sanitary conditions (HSC) or low sanitary conditions (LSC). A contrast in sanitary conditions was generated by imposing to the pigs differences in strategy for vaccination against pathogens, cleaning and hygiene protocol, antibiotic treatment and deworming. During the growing and finishing period, pigs had ad libitum access to one of four experimental diets, a diet with starch as main energy source or a diet with fat and starch as main energy source, each diet having either basal energy and EAA concentrations (B diet) or increased concentrations in energy and EAA (I diet). The levels of supplementation of EAA and energy in the I diets compared to the B diets were based on a model that calculated the effects of low sanitary conditions on the EAA and energy requirements of pigs. At an age of nine weeks, pigs were moved to the rooms for GF pigs. The HSC GF pigs were fed a starter diet during the first five weeks, followed by a grower diet for four weeks and then a finisher diet till delivery to the slaughterhouse. The LSC GF pigs were fed a starter diet during six weeks, followed by a grower diet for four weeks and then a finisher diet till delivery to the slaughterhouse. In all pens, 8 or 9 GF pigs were housed.
Field cricket genome reveals the footprint of recent, abrupt adaptation in the wild
Pascoal, Sonia ; Risse, Judith E. ; Zhang, Xiao ; Blaxter, Mark ; Cezard, Timothee ; Challis, Richard J. ; Gharbi, Karim ; Hunt, John ; Kumar, Sujai ; Langan, Emma ; Liu, Xuan ; Rayner, Jack G. ; Ritchie, Michael G. ; Snoek, Basten L. ; Trivedi, Urmi ; Bailey, Nathan W. - \ 2020
Evolution Letters 4 (2020)1. - ISSN 2056-3744 - p. 19 - 33.
Evolutionary adaptation is generally thought to occur through incremental mutational steps, but large mutational leaps can occur during its early stages. These are challenging to study in nature due to the difficulty of observing new genetic variants as they arise and spread, but characterizing their genomic dynamics is important for understanding factors favoring rapid adaptation. Here, we report genomic consequences of recent, adaptive song loss in a Hawaiian population of field crickets (Teleogryllus oceanicus). A discrete genetic variant, flatwing, appeared and spread approximately 15 years ago. Flatwing erases sound‐producing veins on male wings. These silent flatwing males are protected from a lethal, eavesdropping parasitoid fly. We sequenced, assembled and annotated the cricket genome, produced a linkage map, and identified a flatwing quantitative trait locus covering a large region of the X chromosome. Gene expression profiling showed that flatwing is associated with extensive genome‐wide effects on embryonic gene expression. We found that flatwing male crickets express feminized chemical pheromones. This male feminizing effect, on a different sexual signaling modality, is genetically associated with the flatwing genotype. Our findings suggest that the early stages of evolutionary adaptation to extreme pressures can be accompanied by greater genomic and phenotypic disruption than previously appreciated, and highlight how abrupt adaptation might involve suites of traits that arise through pleiotropy or genomic hitchhiking.
Supplementation of lamb diets with vitamin E and rosemary extracts on meat quality parameters
Leal, Leonel N. ; Beltrán, José A. ; Marc, B. ; Bello, José M. ; Hartog, Leo A. den; Hendriks, Wouter H. ; Martín-Tereso, Javier - \ 2020
Journal of the Science of Food and Agriculture 100 (2020)7. - ISSN 0022-5142 - p. 2922 - 2931.
all-rac-α-tocopheryl acetate - colour - lipid oxidation - modified-atmosphere packaging - rosemary extract - vitamin E
BACKGROUND: Supranutritional supplementation of lamb diets with α-tocopherol is an effective method to reduce lipid oxidation and colour deterioration in meat products. However, alternative antioxidant sources have been proposed to replace the supranutritional vitamin E applications. RESULTS: Indoor concentrate-fed Rasa Aragonesa male lambs (n = 480) were supplemented with increasing levels of all-rac-α-tocopheryl acetate (0.25, 0.5, 1.0 g kg−1 compound feed), rosemary extract (0.20, 0.40, or 0.80 g kg−1 compound feed), or rosemary extract embedded in a fat matrix (0.20, 0.40, or 0.80 g kg−1 compound feed) for 14 days before slaughter. The longissimus thoracis et lumborum muscle from three lambs per pen (18 lambs per treatment) were modified-atmosphere packaged (70% O2 + 30% CO2) and maintained under retail conditions for 14 days. Supranutritional supplementation with antioxidants had no effect (P > 0.05) on average daily weight gain, feed intake, and feed efficiency. Rosemary extract supplementation (with or without fat embedment) had no effect on lipid oxidation, myoglobin forms, or colour stability parameters, regardless of the dose. All vitamin E supplementation levels significantly affected lipid oxidation, colour stability (L*, C*, and h), myoglobin forms, and meat discoloration parameters compared with non-supplemented lambs. CONCLUSIONS: This study demonstrates that, unlike vitamin E, neither dose nor protection of the rosemary extract had an effect on lipid oxidation or meat colour stability of lambs during the 14 days of storage under retail conditions.
Higher education students’ perceived readiness for computer-supported collaborative learning
Khalifeh, Ghodratolah ; Noroozi, Omid ; Farrokhnia, Mohammadreza ; Talaee, Ebrahim - \ 2020
Multimodal Technologies and Interaction 4 (2020)2. - ISSN 2414-4088
Computer ownership - Computer-supported collaborative learning (CSCL) - Gender - Higher education students - Major of study - Perceived readiness - Technology readiness
The purpose of this research was to study the perceived readiness of higher education students for computer-supported collaborative learning (CSCL). Moreover, the role of important demographic variables, such as gender, major of study, and computer ownership, was examined in students’ perceived readiness and its sub-scales. The data was collected from 326 higher education students of four study groups from a state university in Iran. MANOVA analysis was conducted to explore the possible role of the demographic variables in students’ perceived readiness for CSCL. Most of the participants showed high readiness for CSCL. The male participants demonstrated more online learning aptitude compared to females. A statistically significant difference was found in the online learning aptitude of the respondents majoring in engineering and basic sciences with the rest of the participants. Furthermore, the students with a personal computer, laptop, or tablet demonstrated higher levels of readiness for CSCL and online learning aptitude.
Gut microbiota from persons with attention-deficit/hyperactivity disorder affects the brain in mice
Tengeler, Anouk C. ; Dam, Sarita A. ; Wiesmann, Maximilian ; Naaijen, Jilly ; Bodegom, Miranda Van; Belzer, Clara ; Dederen, Pieter J. ; Verweij, Vivienne ; Franke, Barbara ; Kozicz, Tamas ; Arias Vasquez, Alejandro ; Kiliaan, Amanda J. - \ 2020
Microbiome 8 (2020)1. - ISSN 2049-2618
ADHD - Behavior - DTI - Functional connectivity - Gray and white matter integrity - Microbiota - rs-fMRI
Background: The impact of the gut microbiota on host physiology and behavior has been relatively well established. Whether changes in microbial composition affect brain structure and function is largely elusive, however. This is important as altered brain structure and function have been implicated in various neurodevelopmental disorders, like attention-deficit/hyperactivity disorder (ADHD). We hypothesized that gut microbiota of persons with and without ADHD, when transplanted into mice, would differentially modify brain function and/or structure. We investigated this by colonizing young, male, germ-free C57BL/6JOlaHsd mice with microbiota from individuals with and without ADHD. We generated and analyzed microbiome data, assessed brain structure and function by magnetic resonance imaging (MRI), and studied mouse behavior in a behavioral test battery. Results: Principal coordinate analysis showed a clear separation of fecal microbiota of mice colonized with ADHD and control microbiota. With diffusion tensor imaging, we observed a decreased structural integrity of both white and gray matter regions (i.e., internal capsule, hippocampus) in mice that were colonized with ADHD microbiota. We also found significant correlations between white matter integrity and the differentially expressed microbiota. Mice colonized with ADHD microbiota additionally showed decreased resting-state functional MRI-based connectivity between right motor and right visual cortices. These regions, as well as the hippocampus and internal capsule, have previously been reported to be altered in several neurodevelopmental disorders. Furthermore, we also show that mice colonized with ADHD microbiota were more anxious in the open-field test. Conclusions: Taken together, we demonstrate that altered microbial composition could be a driver of altered brain structure and function and concomitant changes in the animals' behavior. These findings may help to understand the mechanisms through which the gut microbiota contributes to the pathobiology of neurodevelopmental disorders. [MediaObject not available: See fulltext.]