Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids in feed and food, in particular in lupins and lupin-derived products
    Schrenk, Dieter ; Bodin, Laurent ; Chipman, James Kevin ; Mazo, Jesús del; Grasl-Kraupp, Bettina ; Hogstrand, Christer ; Hoogenboom, Laurentius ; Leblanc, Jean Charles ; Nebbia, Carlo Stefano ; Nielsen, Elsa ; Ntzani, Evangelia ; Petersen, Annette ; Sand, Salomon ; Schwerdtle, Tanja ; Vleminckx, Christiane ; Wallace, Heather ; Alexander, Jan ; Cottrill, Bruce ; Dusemund, Birgit ; Mulder, Patrick ; Arcella, Davide ; Baert, Katleen ; Cascio, Claudia ; Steinkellner, Hans ; Bignami, Margherita - \ 2019
    EFSA Journal 17 (2019)11. - ISSN 1831-4732
    feed - food - lupanine - Lupin - margin of exposure (MOE) - quinolizidine alkaloid - sparteine

    The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids (QAs) in feed and food. This risk assessment is limited to QAs occurring in Lupinus species/varieties relevant for animal and human consumption in Europe (i.e. Lupinus albus L., Lupinus angustifolius L., Lupinus luteus L. and Lupinus mutabilis Sweet). Information on the toxicity of QAs in animals and humans is limited. Following acute exposure to sparteine (reference compound), anticholinergic effects and changes in cardiac electric conductivity are considered to be critical for human hazard characterisation. The CONTAM Panel used a margin of exposure (MOE) approach identifying a lowest single oral effective dose of 0.16 mg sparteine/kg body weight as reference point to characterise the risk following acute exposure. No reference point could be identified to characterise the risk of chronic exposure. Because of similar modes of action for QAs, the CONTAM Panel used a group approach assuming dose additivity. For food, the highest mean concentration of Total QAs (TotQAs) (i.e. the 6 most abundant QAs) was found in lupin seed samples classified as ‘Lupins (dry) and similar-’. Due to the limited data on occurrence and consumption, dietary exposure was calculated for some specific scenarios and no full human health risk characterisation was possible. The calculated margin of exposures (MOEs) may indicate a risk for some consumers. For example, when lupin seeds are consumed without a debittering step, or as debittered lupin seeds high in QA content and when ‘lupin-based meat imitates’ are consumed. For horses, companion and farm animals, other than salmonids, the available database on adverse effects was too limited to identify no-observed-adverse-effect levels and/or lowest-observed-adverse-effect levels and no risk characterisation was possible. For salmonids, the CONTAM Panel considers the risk for adverse effects to be low.

    Food Safety Issues Related to Uses of Insects for Feeds and Foods
    Fels-Klerx, H.J. van der; Camenzuli, L. ; Belluco, S. ; Meijer, N. ; Ricci, A. - \ 2018
    Comprehensive Reviews in Food Science and Food Safety 17 (2018)5. - ISSN 1541-4337 - p. 1172 - 1183.
    edible insects - feed - food - review - safety

    Edible insects are expected to become an important nutrient source for animals and humans in the Western world in the near future. However, before insects can be put on the market, the safety of their use for feed and food is warranted. This literature study was prepared to provide an overview of the actual knowledge of possible food safety hazards, including chemical, microbiological, and allergenic agents and prions, to human and animal health upon the use of insects for food and feed, and to highlight data gaps and suggest the way forward. From the data available, heavy metals of concern are cadmium in black soldier fly and arsenic in yellow mealworm larvae. Investigated mycotoxins do not seem to accumulate. Residues of pesticides, veterinary drugs, and hormones, as well as dioxins and PCBs, are sometimes found in insects. Contamination of insects with pathogens to human health is a consequence of a combination of the substrates used and the farming and processing steps applied. Insects harbor a wide variety of microorganisms, and some human pathogenic bacteria may be present. In addition, insects may harbor and transmit parasites. There is no evidence so far insects may harbor pathogenic viruses or prions, but they may act as vectors. Insects and insect-derived products may have allergenic potential. In this review, evidence on some safety aspects is displayed, and data gaps are identified. Recommendations are given for future research to fill the most relevant data gaps.

    Soya bean meal increases litter moisture and foot pad dermatitis in maize and wheat based diets for turkeys but maize and non-soya diets lower body weight
    Hocking, P.M. ; Vinco, L.J. ; Veldkamp, T. - \ 2018
    British Poultry Science 59 (2018)2. - ISSN 0007-1668 - p. 227 - 231.
    Cereal - dermatitis - diet - electrolyte balance - feed - feed intake - litter moisture - protein
    1. A 2 × 2 factorial experiment was conducted to compare the effects of wheat or maize based diets differing in dietary electrolyte balance (DEB) on litter moisture and foot pad dermatitis (FPD) at 4, 8 and 12 weeks of age in heavy-medium turkeys. A second objective was to investigate the effects on foot pad dermatitis of the interaction between dietary composition and artificially increasing litter moisture by adding water to the litter. 2. High DEB diets contained soya as the main protein source whereas low DEB diets did not contain soya bean meal. Diets were formulated to be iso-caloric and iso-nitrogenous in each of 3 successive 4-week phases following recommended dietary compositions. DEB concentrations were 330, 290 and 250 mEq/kg in high DEB diets and 230, 200 and 180 mEq/kg in low DEB diets. 3. Litter moisture and mean FPD score were higher in turkeys fed on high DEB diets compared with low DEB diets whereas there was no difference between maize and wheat. 4. Food intake was similar and body weight was lower after litter moisture was artificially raised in the wet compared with the dry litter treatment and there was no interaction with dietary composition. 5. Mean body weight and feed intake were higher in turkeys fed on wheat compared with maize and in high DEB compared with low DEB diets at 12 weeks of age. 6. Lowering dietary DEB for turkeys may improve litter moisture and lower the prevalence of FPD in commercial turkey flocks.
    The Effect of Different Feed and Stocking Densities on Growth and Survival Rate of Blue Swimming Crablets (Portunus pelagicus)
    Ariyati, Restiana W. ; Rejeki, Sri ; Bosma, R.H. - \ 2017
    feed - stocking density - blue swimming - crablet
    Global animal production and nitrogen and phosphorus flows
    Liu, Qian ; Wang, Jingmeng ; Bai, Zhaohai ; Ma, Lin ; Oenema, Oene - \ 2017
    Soil Research 55 (2017)5-6. - ISSN 1838-675X - p. 451 - 462.
    feed - livestock density - manure management - nitrogen balance - nitrogen use efficiency - phosphorus balance - phosphorus use efficiency - system
    Animal production systems provide nutritious food for humans, income and survivability for numerous smallholder farms and transform residues to valuable products. However, animal production is implicated in human health issues (diet-related diseases, zoonosis, antimicrobial resistance) and environmental burdens (ammonia and greenhouse gas emissions, eutrophication of surface waters, biodiversity loss). This paper reviews changes in global animal production and associated nitrogen (N) and phosphorus (P) flows over the past 50 years, during which time total animal production roughly tripled. Cattle still dominate the world in terms of animal biomass, but the number and total production of pigs and poultry have increased faster. Animal production systems are highly diverse and respond to changes in markets. Specialised systems have become more dominant, especially in developed and rapidly developing countries. The annual production of N and P in manure is similar to the amounts of N and P in synthetic fertiliser produced annually, but manure nutrients are often not recycled effectively and used efficiently by plants. Nutrient losses greatly depend on the system, management and regulations. Nitrogen and P use efficiency (NUE and PUE respectively) at the animal level is in the range 5-45%, depending on animal category, feeding and management. NUE of mixed crop-animal systems may range from 5% to 65% depending on NUE at the animal level, and the utilisation of manure nitrogen and new nitrogen inputs. Potentially, values for PUE are higher than those for NUE. Solutions for improving NUE and PUE in animal production are based on a coherent set of activities in the whole chain of 'feed production-animal production-manure management'. A high efficiency at the system level is achieved through combination of high NUE and PUE at the animal level and effective recycling and utilisation of manure N and P in crop production. Specific regional regulations (low-emission manure storage and application, proper application limits and timing) greatly contribute to high efficiency at a system level.
    Nutritional composition of black soldier fly (Hermetia illucens) prepupae reared on different organic waste substrates
    Spranghers, Thomas ; Ottoboni, Matteo ; Klootwijk, Cindy ; Ovyn, Anneke ; Deboosere, Stefaan ; Meulenaer, Bruno De; Michiels, Joris ; Eeckhout, Mia ; Clercq, Patrick De; Smet, Stefaan De - \ 2017
    Journal of the Science of Food and Agriculture 97 (2017)8. - ISSN 0022-5142 - p. 2594 - 2600.
    black soldier fly - fatty acid, amino acid - feed - protein - vegetable waste processing
    BACKGROUND: Black soldier fly larvae are converters of organic waste into edible biomass, of which the composition may depend on the substrate. In this study, larvae were grown on four substrates: chicken feed, vegetable waste, biogas digestate, and restaurant waste. Samples of prepupae and substrates were freeze-dried and proximate, amino acid, fatty acid and mineral analyses were performed. RESULTS: Protein content of prepupae varied between 399 and 431 g kg−1 dry matter (DM) among treatments. Differences in amino acid profile of prepupae were small. On the other hand, the ether extract (EE) and ash contents differed substantially. Prepupae reared on digestate were low in EE and high in ash (218 and 197 g kg−1 DM, respectively) compared to those reared on vegetable waste (371 and 96 g kg−1 DM, respectively), chicken feed (336 and 100 g kg−1 DM, respectively) and restaurant waste (386 and 27 g kg−1 DM, respectively). Prepupal fatty acid profiles were characterised by high levels of C12:0 in all treatments. CONCLUSION: Since protein content and quality were high and comparable for prepupae reared on different substrates, black soldier fly could be an interesting protein source for animal feeds. However, differences in EE and ash content as a function of substrate should be considered.
    Pig behaviour linked to sanitary conditions and diets
    Meer, Y. van der; Gerrits, W.J.J. ; Jansman, A.J.M. ; Kemp, B. ; Bolhuis, J.E. - \ 2017
    Pig Progress
    pigs - pig - feed - abnormal behaviour - health - research - housing systems - tail biting
    There is a connection between damaging behaviour in pigs, sanitary conditions and diet formulations. How exactly, was presented by Dutch researchers recently.
    Microscopic recognition and identification of fish meal in compound feeds
    Raamsdonk, L.W.D. van; Prins, Theo ; Rhee, N. van de; Vliege, J.J.M. ; Pinckaers, V.G.Z. - \ 2017
    Food Additives & Contaminants. Pt. A, Chemistry, Analysis, Control, Exposure & Risk Assessment 34 (2017)8. - ISSN 1944-0049 - p. 1364 - 1376.
    alizarin - anosteocytic bones - Determinator - expert system - feed - fish bone structure - Fish meal - gill - scale
    Fish meal is an accepted ingredient in compound feed. Unauthorised application is primarily enforced by visual inspection, i.e., microscopy. In order to document the visually available diversity, fragments of bones and scales of 17 teleost fish species belonging to seven different orders were investigated for their diversity in the presence of structural elements: lacunae and canaliculae in bone fragments and type of growth rings and teeth of scale fragments. Despite the classical division into cellular bones and acellular bones of teleost fish, i.e., whether or not possessing osteocytes, the current examinations revealed patterns of lacunae, in some types accompanied with canaliculae, in all 17 species investigated. In total seven types of bone structures were defined, and six types of scale structures. Profiles with the relative frequency of each bone type per species were established. The share of acellular bone fragments appeared to be related to the evolutionary position of the species. Results of proficiency tests for the detection of fish meal reveal that in most cases the sensitivity and specificity for the detection of fish meal ranges from sufficient to perfect. Only some specified circumstances can hamper proper recognition and identification, most notably salmon bone fragments mimicking bone fragments from terrestrial animals, and pieces of hydrolysed proteins or minerals mimicking acellular fish bone fragments. The expertise gained in this study would help to improve the distinction between fish meal and terrestrial animal material in compound feed, and it supports the application of the species-to-species ban with respect to the valorisation of by-products from fish farms in aquafeed. In a broader perspective, the current expertise might be helpful to detect fraud throughout the feed/food production chain. The matrix of characteristics versus species is implemented in a data model running in the expert system ‘Determinator’ for facilitating identification.
    Origin authentication of distillers' dried grains and solubles (DDGS) - application and comparison of different analytical strategies
    Vermeulen, P. ; Nietner, T. ; Haughey, S.A. ; Yang, Z. ; Tena, N. ; Chmelarova, H. ; Ruth, S.M. van; Tomaniova, M. ; Boix, A. ; Han, L. ; Elliott, C.T. ; Baeten, V. ; Fauhl-Hassek, C. - \ 2015
    Analytical and Bioanalytical Chemistry 407 (2015)21. - ISSN 1618-2642 - p. 6447 - 6461.
    flight mass-spectrometry - geographical origin - calibration transfer - chemometric tools - fatty-acid - feed - transferability - instruments - food - ms
    In the context of products from certain regions or countries being banned because of an identified or non-identified hazard, proof of geographical origin is essential with regard to feed and food safety issues. Usually, the product labeling of an affected feed lot shows origin, and the paper documentation shows traceability. Incorrect product labeling is common in embargo situations, however, and alternative analytical strategies for controlling feed authenticity are therefore needed. In this study, distillers' dried grains and solubles (DDGS) were chosen as the product on which to base a comparison of analytical strategies aimed at identifying the most appropriate one. Various analytical techniques were investigated for their ability to authenticate DDGS, including spectroscopic and spectrometric techniques combined with multivariate data analysis, as well as proven techniques for authenticating food, such as DNA analysis and stable isotope ratio analysis. An external validation procedure (called the system challenge) was used to analyze sample sets blind and to compare analytical techniques. All the techniques were adapted so as to be applicable to the DDGS matrix. They produced positive results in determining the botanical origin of DDGS (corn vs. wheat), and several of them were able to determine the geographical origin of the DDGS in the sample set. The maintenance and extension of the databanks generated in this study through the analysis of new authentic samples from a single location are essential in order to monitor developments and processing that could affect authentication.
    Effects of diet composition and ultrasound treatment on particle size distribution and carbon bioavailability in feces of rainbow trout
    Meriac, A. ; Tilburg, T. van; Eding, E.H. ; Kamstra, A. ; Schrama, J.W. ; Verreth, J.A.J. - \ 2015
    Aquacultural Engineering 65 (2015). - ISSN 0144-8609 - p. 10 - 16.
    recirculating aquaculture systems - activated-sludge - anaerobic-digestion - waste-water - feed - fish - denitrification - digestibility - pretreatment - sonication
    The effect of a high and low non-starch polysaccharide diet (HNSP and LNSP diet) and ultrasound treatment on particle size distribution and carbon bioavailability in fecal waste of rainbow trout (Oncorynchus mykiss) was studied. Feces were collected from four flow-through fish tanks, two tanks fed the HNSP diet and two the LNSP diet. The collected feces were sonicated (disintegrated) in duplicate with high-intensity (0.6 W/ml), low-frequency (f = 20 Hz) ultrasound at five different energy levels (0.6 W/ml for 0, 0.25, 1, 4, and 16 min). The particle size distribution of the treated feces samples was measured by wet sieving (1000, 500, 200, 100, 63, 36, 1.2 µm screen size) and total suspended solids (TSS) measurement. Carbon bioavailability in sonicated fecal waste samples was determined with oxygen uptake rate (OUR) tests. The results showed that: (1) feces from the HNSP diet contained significant more particulate material and bigger particles; (2) carbon bioavailability was almost three times higher in untreated LNSP feces when compared with HNSP feces; (3) almost 50% of HNSP feces could have been recovered on a microscreen of 36 µm after wet sieving, whereas it was only 10% for LNSP feces; (4) the production of small particles (1.2–36 µm), which could pass a drum filter screen and potentially accumulate in RAS, was approximately 50 g/kg feed, showing no significant differences between diets; (5) sonication increased fecal dry matter below 36 µm (p = 0.015), but it had no significant effect on the median particle size; (6) sonication increased carbon bioavailability with 7–10% for the HNSP feces (p = 0.037); (7) fecal particles withstood up to 16 min sonication at an intensity of 0.6 W/ml and a frequency of 20 Hz corresponding to specific energy input of 20,000 kJ/kg DM without major changes in particle size distribution. The results of this study indicate that the applied ultrasound treatment of fecal waste is not an effective method to increase short-term carbon bioavailability.
    Sustainability assessment of oilseed fractionation processes: A case study on lupin seeds
    Berghout, J.A.M. ; Pelgrom, P.J.M. ; Schutyser, M.A.I. ; Boom, R.M. ; Goot, A.J. van der - \ 2015
    Journal of Food Engineering 150 (2015). - ISSN 0260-8774 - p. 117 - 124.
    functional-properties - exergy analysis - protein - food - feed - fiber - acid
    Traditional ingredient production focusses on high purity and yield, resulting in energy- and resource-intensive fractionation processes. We explored alternative fractionation routes for oilseeds by focussing on functionality and optimal resource use. Lupin seeds were taken as model material because they are rich in protein and oil and they can be grown in moderate climate conditions. Dry fractionation yields functional protein-enriched flours without using water, consumes the least energy and exergy losses are low. Purer protein fractions are obtained via conventional wet or aqueous fractionation, but these processes require large amounts of water and an energy-intensive drying step. With the use of exergy analysis, we demonstrate that water and energy consumption can be reduced by replacing drying steps with concentration steps and by combining dry and aqueous fractionation processes. Finally, by valorising side streams, the exergetic efficiency of all fractionation processes increases.
    Denitrification on internal carbon sources in RAS is limited by fibers in fecal waste of rainbow trout
    Meriac, A. ; Eding, E.H. ; Kamstra, A. ; Busscher, J.P. ; Schrama, J.W. ; Verreth, J.A.J. - \ 2014
    Aquaculture 434 (2014). - ISSN 0044-8486 - p. 264 - 271.
    recirculating aquaculture systems - single-sludge denitrification - acid-insoluble ash - nitrate removal - digestibility - feed - fish - effluents - digestion - culture
    Denitrification on internal carbon sources offers the advantage to control nitrate levels in recirculating aquaculture systems (RAS) by using the fecal carbon produced within the husbandry system. However, it is not clear to which extent fecal carbon can be utilized by the microbial community within a denitrification reactor. Especially fibers can hamper the bioavailability of carbon in fecal waste. Therefore, this study investigated the nitrogen removal capacity of a denitrification reactor using fecal waste with a high fiber content as the only carbon source in RAS. Furthermore, we investigated to which extent fibers were utilized as a carbon source within the reactor. Four identical small-scale RAS (V = 460 L) were stocked with 25 rainbow trout of ~ 110 g, and operated at a water exchange rate of ~ 200 L/kg of feed DM. Two RAS served as controls without denitrification and two RAS were upgraded with an upflow sludge blanket denitrification reactor (V = 10.5 L). During the six weeks of experiment, we determined COD (chemical oxygen demand, measure for organic carbon) and N balances for all systems and analyzed the composition of the collected solids. The denitrification reactors were able to remove 19 g N/kg of feed DM, or 48% of the metabolic nitrogen waste produced by the fish. Based on the COD balances, 44% of the supplied fecal COD was degraded in the reactor. Hemicellulose and cellulose degradability was ~ 50%, accounting for 45% to the total degraded COD. Under steady state conditions, 4.4 g of biodegradable COD needed to be oxidized to reduce 1 g of nitrogen, indicating respiratory COD losses of approximately 50%. This experiment successfully demonstrated that denitrification on internal carbon sources using a high fiber diet could remove half of the nitrogen waste produced by the fish. Although fibers limited carbon bioavailability, half of the cellulose and hemicellulose present in the fecal waste was utilized in the denitrification reactor.
    Evaluation of the nutritive value of muiumba (Baikiaea plurijuga) seeds: chemical composition, in vitro organic matter digestibility and in vitro gas production
    Rodrigues, M.A.M. ; Lourenço, A.L. ; Cone, J.W. ; Nunes, F.M. ; Santos, A.S. ; Cordeiro, J.M.M. ; Guedes, C.M.V. ; Ferreira, L.M.M. - \ 2014
    SpringerPlus 3 (2014). - ISSN 2193-1801
    nonstarch polysaccharides - production profiles - plant materials - dietary fiber - tree fodder - fermentation - feed - fractions - leaves - fruits
    One of the main constraints hindering the increase of animal production in semi-arid regions of Africa is the inadequate supply of nutrients during the dry season. Incorporation of alternative feed resources in ruminant diets during this period could be a viable approach to overcome these limitations. The objective of this study was to evaluate the nutritive value of muiumba (Baikiaea plurijuga) tree seeds as an alternative nutrient source for ruminants. Muiumba seeds were compared to other eight feedstuffs including two cereal grains (corn and oat), two wheat by-products (wheat bran and distilled wheat) and four protein meals (coconut meal, sunflower meal, soybean meal and rapeseed meal) as to its chemical composition, in vitro organic matter digestibility (IVOMD) and in vitro gas production. The moderate crude protein concentrations (145 g/kg DM) of muiumba seeds indicate that this feedstuff could not be used as a protein supplement, contrarily to the majority of multipurpose tree seeds. Although the starch content was scarce (15 g/kg DM), the low neutral detergent fibre (235 g/kg DM), low molecular weight sugar (76.1 g/kg DM) and non-starch polysaccharide (510.5 g/kg DM) contents indicate that this feedstuff has potential feeding value. This was confirmed by the IVOMD (0.770) and by the data provided by the in vitro gas production showing that muiumba seeds had high (P <0.05) maximum gas production and fractional fermentation rates, suggesting that these seeds are characterized by a highly fermentable fraction.
    Critical parameters in cost-effective alkaline extraction for high protein yield from leaves
    Zhang, C. ; Sanders, J.P.M. ; Bruins, M.E. - \ 2014
    Biomass and Bioenergy 67 (2014). - ISSN 0961-9534 - p. 466 - 472.
    leaf protein - functional-properties - chemical-composition - amino-acids - tea-leaves - biomass - concentrate - refinery - feed
    Leaves are potential resources for feed or food, but their applications are limited due to a high proportion of insoluble protein and inefficient processing. To overcome these problems, parameters of alkaline extraction were evaluated using green tea residue (GTR). Protein extraction could be maximized to 95% of total protein, and, after precipitation by pH adjustment to 3.5, 85% of extracted protein was recovered with a purity of 52%. Temperature, NaOH amount, and extraction time are the protein yield determining parameters, while pH and volume of extraction liquid are critical parameters for production cost. The cost of energy and chemicals for producing 1 t GTR proteins is minimized to 102€, and its nutritional value is comparable to soybean protein. Furthermore, this technology was successfully applied to other sources of biomass and has potential to be used as a part of an integrated bio-refinery process.
    Rapid enzymatic hydrolysis of masked deoxynivalenol and zearalenone prior to liquid chromatography mass spectrometry or immuniassay analysis
    Nielen, M.W.F. ; Weijers, C.A.G.M. ; Peters, J. ; Weignerová, L. ; Zuilhof, H. ; Franssen, M.C.R. - \ 2014
    World Mycotoxin Journal 7 (2014)2. - ISSN 1875-0710 - p. 107 - 113.
    naturally contaminated wheat - mycotoxin analysis - beer - feed - food
    Recently it has been shown that conjugates (‘masked mycotoxins’) may contribute to the total daily intake of hazardous mycotoxins. Therefore, there is an urgent need for rapid analysis methods that assess the level of both free and masked mycotoxins in food and feed. However, the analysis of masked mycotoxins by either immunoassays or instrumental methods, such as liquid chromatography tandem mass spectrometry (LC-MS/MS), is severely hindered by the lack of standards and the unpredictable cross-reactivity profiles of the available antibodies. In this work, 26 enzymes were explored for rapid hydrolysis of masked mycotoxins using deoxynivalenol-3-glucoside (DON-3G) as model compound. Following initial screening, the most promising enzyme, a fungal 1,3-ß-glucanase (laminarinase), was investigated in detail and found to be fit-for-purpose, providing complete conversions in minutes rather than hours according to LC-MS/MS analyses. As a proof of concept, the enzymatic pretreatment was applied to an extract of beer containing DON-3G. In addition, the feasibility of a fully automated enzymatic pretreatment of masked mycotoxin standards in an autosampler was demonstrated in an imaging surface plasmon resonance immunoassay set-up. Such an automated pretreatment was found to be equally applicable to other mycotoxin conjugates, as shown by the conversion of zearalenone-14-ß-D-glucopyranoside and zearalenone-14-sulphate, in the latter case using a sulphatase enzyme. It is envisaged that laminarinase could be useful for other masked mycotoxins as well.
    Chopped or long roughage: what do calves prefer? Using cross point analysis of double demand functions
    Webb, L.E. ; Bak Jensen, M. ; Engel, B. ; Reenen, C.G. van; Gerrits, W.J.J. ; Boer, I.J.M. de; Bokkers, E.A.M. - \ 2014
    PLoS ONE 9 (2014)2. - ISSN 1932-6203 - 8 p.
    different rooting materials - affecting diet selection - veal calves - rumen development - chewing activity - particle length - food preference - animal-welfare - feed - behavior
    The present study aimed to quantify calves'(Bos taurus) preference for long versus chopped hay and straw, and hay versus straw, using cross point analysis of double demand functions, in a context where energy intake was not a limiting factor. Nine calves, fed milk replacer and concentrate, were trained to work for roughage rewards from two simultaneously available panels. The cost (number of muzzle presses) required on the panels varied in each session (left panel/right panel): 7/35, 14/28, 21/21, 28/14, 35/7. Demand functions were estimated from the proportion of rewards achieved on one panel relative to the total number of rewards achieved in one session. Cross points (cp) were calculated as the cost at which an equal number of rewards was achieved from both panels. The deviation of the cp from the midpoint (here 21) indicates the strength of the preference. Calves showed a preference for long versus chopped hay (cp ¿=¿14.5; P ¿=¿0.004), and for hay versus straw (cp ¿=¿38.9; P¿=¿0.004), both of which improve rumen function. Long hay may stimulate chewing more than chopped hay, and the preference for hay versus straw could be related to hedonic characteristics. No preference was found for chopped versus long straw (cp ¿=¿20.8; P¿=¿0.910). These results could be used to improve the welfare of calves in production systems; for example, in systems where calves are fed hay along with high energy concentrate, providing long hay instead of chopped could promote roughage intake, rumen development, and rumination.
    Nitrogen and Phosphorus Use Efficiencies in Dairy Production in China
    Bai, Z.H. ; Ma, L. ; Oenema, O. ; Chen, Q. ; Zhang, F.S. - \ 2013
    Journal of Environmental Quality 42 (2013)4. - ISSN 0047-2425 - p. 990 - 1001.
    nutrient flows - farming system - food-chain - management - agriculture - losses - feed - performance - industry
    Milk production has greatly increased in China recently, with significant impacts on the cycling of nitrogen (N) and phosphorus (P). However, nutrient flows within the changing dairy production system are not well quantified. The aim of this study was to increase the quantitative understanding of N and P cycling and utilization in dairy production through database development and simulation modeling. In 2010, of the entire 1987 and 346 thousand tons (Gg) of N and P input, only 188 Gg N and 31 Gg P ended up in milk. The average N and P use efficiencies were 24 and 25%, respectively, at the whole system level. Efficiencies differed significantly between the four dairy systems. Losses of N from these systems occurred via NH3 volatilization (33%), discharge (27%), denitrification (24%), NO3 leaching and runoff (16%), and N2O emission (1%). Industrial feedlots use less feed per kg milk produced than traditional systems, and rely more on high-quality feed from fertilized cropland; they have very poor recycling of manure nutrients to cropland. As industrial feedlot systems are booming, overall mean N and P use efficiencies will increase at herd level but will decrease at the whole dairy production system level unless manure N and P are used more efficiently through reconnecting China's feed and dairy production sectors.
    The disposition of oxytetracycline to feathers after poultry treatment
    Berendsen, B.J.A. ; Bor, G. ; Gerritsen, H.W. ; Jansen, L.J.M. ; Zuidema, T. - \ 2013
    Food Additives & Contaminants. Pt. A, Chemistry, Analysis, Control, Exposure & Risk Assessment 30 (2013)12. - ISSN 1944-0049 - p. 2102 - 2107.
    tandem mass-spectrometry - growth-promoting agents - residue analysis - veterinary drugs - bovine - feed
    In the combat against bacterial resistance, there is a clear need to check the use of antibiotics in animal husbandry, including poultry breeding. The use of chicken feathers as a tool for the detection of use of antibiotics was investigated. An extraction method for the analysis of oxytetracycline (OTC) from feathers was developed and was tested by using incurred feathers obtained from a controlled animal treatment study. The use of McIlvain-ethylenediaminetetraacetic acid buffer only in combination with acetone gave the highest extraction yield, indicating the need of an organic solvent for feather extraction. By using the developed method, it was found that after a withdrawal time, the OTC concentration in feathers is in the mg kg(-1) range, far higher than that in muscle and liver tissue. Based on the analysis of individual segments of feathers from OTC-treated chicken, evidence was found supporting the hypothesis of secretion of antibiotics through the uropygial gland and external spread over feathers by grooming behaviour. It was also found that part of the administered OTC is built into the feather rachis. Finally, we provide the first evidence that the analysis of individual segments of the rachis can be used as a tool to discriminate among different treatment strategies, for example, therapeutic versus subtherapeutic. As a result, we concluded that the analysis of feathers is an extremely valuable tool in residue analysis of antibiotics.
    Evaluation of a Commercial ELISA for Detection of Ruminant Processed Animal Proteins in Non-Ruminant Processed Animal Proteins
    Bremer, M.G.E.G. ; Margry, R.J.C.F. ; Vaessen, J.C.H. ; Doremalen, A.M.H. van; Palen, J.G.P. van der; Kaathoven, R.G.C. van; Kemmers-Voncken, A.E.M. ; Raamsdonk, L.W.D. van - \ 2013
    Journal of AOAC International 96 (2013)3. - ISSN 1060-3271 - p. 552 - 559.
    plant sterilization conditions - shrimp litopenaeus-vannamei - linked-immunosorbent-assay - bone meals - classical microscopy - rendered meat - by-products - feed - pcr - identification
    Due to a growing aquaculture industry, demand for high-quality proteins for aquatic feeds is increasing. Non-ruminant processed animal proteins (PAPs) have shown great potential for this purpose. Safe reintroduction of non-ruminant PAPs in aqua feed requires methods that can discriminate ruminant and non-ruminant PAPs at contamination levels at or below 2%. Because the official European Union method lacks species specificity, the performance of MELISA-TEK™ Ruminant, a commercial immunoassay, combined with the MELISA-TEK High Sensitivity Sample Extraction kit was evaluated. Various non-ruminant PAPs spiked with ruminant PAPs (processed at 133, 137, 141, and 145°C) were analyzed. Results showed an overall specificity of 99%, indicating no cross-reaction with non-ruminant PAPs. The sensitivity of the assay strongly depended on both processing temperature and proportion of muscle fibers of the ruminant PAPs. Overall sensitivity of samples with 1 and 2% ruminant PAPs was 92 and 100%, respectively. For ruminant PAPs processed at 133 and 137°C, the sensitivity was 100% for both 1 and 2% ruminant spikes. Overall accuracies were 96 and 99% for 1 and 2% ruminant spikes, respectively. In conclusion, the MELISA-TEK Ruminant assay showed satisfactory results, which makes it a suitable candidate method to enable safe reintroduction of non-ruminant PAPs in aqua feed.
    Ileal microbiota composition of broilers fed various commercial diet compositions
    Hoeven-Hangoor, E. van der; Vossen, J.M.B.M. ; Schuren, F.H.J. ; Verstegen, M.W.A. ; Oliveira, J.E. de; Montijn, R.C. ; Hendriks, W.H. - \ 2013
    Poultry Science 92 (2013)10. - ISSN 0032-5791 - p. 2713 - 2723.
    gradient gel-electrophoresis - fatty-acids - gut microflora - xylanase supplementation - bacterial community - enterococcus-hirae - chickens - performance - ileum - feed
    Microbiota plays a role in the release and absorption of nutrients from feed components, thereby affecting digesta composition and moisture content of the excreta. The objective of the current study was to determine the effects of 5 different diets varying in ingredients (medium-chain fatty acids, nonstarch polysaccharides, and starch) on the microbiota composition of ileal digesta of broiler chickens and excreta DM content. Each treatment was repeated 6 times in cages each containing 18 Ross 308 broilers, with growth performance measured from 0 to 34 d of age and excreta DM and ileal microbiota composition analyzed at 34 d of age. Microbiota composition was evaluated using a novel ribosomal RNA microarray technology containing 370 different probes covering various genera, groups of microbial species, and individual species of the chicken gut microbiota, of which 321 had a signal above the background threshold. Replacing part of the animal fat and soybean oil in the wheat-based diet with medium-chain fatty acids (MCFA; 0.3% C10 and 2.7% C12) improved feed efficiency compared with the other dietary treatments. This coincided with a suppression of gram-positive bacteria belonging to the phylum of the Firmicutes, including Lactobacillus species, and species belonging to the family of the Enterococcaceae and Micrococcaceae, whereas the gram-negative bacteria belonging to the family of the Enterobacteriaceae were promoted. None of the other diets used in the present study notably changed the ileal digesta bacteria composition. Excreta DM content was not affected by dietary treatment. The variation between individual birds per dietary treatment was more pronounced than variation caused by feed composition, with the exception of the digesta microbiota of the birds fed the MCFA diet. It is concluded that a diet with MCFA significantly changes the ileal microbiota composition, whereas the effect of the other diets on the composition of the microbiota and excreta DM content is small in broiler chickens.
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