Lagere ammoniakemissie bij stalen roosters

Door de roosterbalk smaller te maken is een grotere mestdoorlaat mogelijk. Dit is alleen mogelijk met andere materialen zoals staal

Minder slippartijen op geprofileerde vloeren

De resultaten geven aan dat door profilering het aantal slippartijen vermindert

Kunststofgrasplaten geschikt als koepad?

Op het lagekostenbedrijf is een proef uitgevoerd waarin kunststofgrasplaten zijn vergeleken met betonplaten als verharding voor het kavelpad

Mestscheiding op lagekostenbedrijf werkt opnieuw goed

Deze resultaten zijn beter dan vorig jaar. Daarnaast worden de resultaten vergeleken met een mechanische mestscheider

Regenwater opvangen voor het vee loont op Lagekostenbedrijf

Het Lagekostenbedrijf in Lelystad heeft ongeveer een jaar een proefopstelling gebruikt om regenwater op te vangen en als drinkwater voor het vee te gebruiken. De kosten voor het aanleggen van de watervoorziening zijn berekend en in een tabel weergegeven, evenals de besparing op de hoeveelheid leidingwater, op basis van de hoeveelheid neerslag van de afgelopen 4 jare

Oriënterend laboratoriumonderzoek naar ammoniakemissie uit bodempakketten voor vrijloopstallen = Laboratory study of ammonia emission from bedding materials of freestall dairy cattle houses

In the Netherlands there is growing interest amongst dairy farmers in new housing systems in which animal welfare and health are improved. A promising system in this area is a loose housing system (without cubicles) where cows have a large area with a soft bedding where they can both being active and rest, so called freestalls. Although these systems are already applied in the USA and Israel, little is known about the environmental impacts, and particularly the ammonia emission. The aim of this study was to get some first impressions of the suitability of different bedding materials, especially concerning ammonia emission. The ammonia emissions of simulated urinations were measured in a laboratory set up with several bedding materials. As non degradable materials, two types of sand with larger and smaller average particle size and one type of rubber shaving were tested. As degradable materials freshly produced press screwed manure (the solid fraction), without (1) and with (2) an added mixture of sawdust and wood chips, composted press screwed manure (3) and (4) mud (peat soil/clay) originating from the small channels in the grasslands in an area with a peat soil with a top soil layer of clay. One week before the laboratory experiment, each of the bedding materials was mixed with fresh dairy cattle feces, urine and press screwed manure to get a quick simulation of the excreta accumulation in beddings in freestalls. Into the non degradable materials less feces and less screw pressed manure were added to simulate an on farm partly removal of feces from the resulting beddings. After preparation the bedding-excreta mixtures were kept one week in boxes in a ventilated house, with similar conditions as in a cow house. After this week, the ammonia emission from a simulated urination was determined in a laboratory set up. The degradable variants were tested both after manually pressing (higher density) and without pressing (lower density) the bedding mixtures in the laboratory set up. Ammonia emissions were higher with the non degradable bedding materials than with the degradable materials. The emission of the mud bedding mixture was low after 4, 24 and 72 hours. The emission of the mixture of screw pressed manure, sawdust, and wood chips with added excreta was very low after 4 hours. However after 24 and 72 hours the higher density variant showed a remarkable increase of ammonia emission while the low density variant did not. Between the tested bedding variants substantial differences in ammonia emissions were measured. Only a quick and short simulation was done to get first impressions. In reality, longer term accumulation of excreta in the beddings may result in build up of layers, silting up and different conversion rates in the freestall beddings. This may result in higher or lower emissions. The ranking of bedding materials may change as a result of this. Further research, also on other gaseous emissions like greenhouse gasses, in real cow barns is recommended to study this time and conditions dependent phenomena in more detai

Control Force Compensation in Ground-Based Flight Simulators

This paper presents the results of a study that investigated if controller force compensations accounting for the inertial force and moment due to the aircraft motion during flight have a significant effect on pilot control behavior and performance. Seven rotorcraft pilots performed a side-step and precision hovering task in light turbulence in the Vertical Motion Simulator. The effects of force compensation were examined for two different simulated rotorcraft: linear and UH-60 dynamics with two different force gradient of the lateral stick control. Four motion configurations were used: large motion, hexapod motion, fixed-base motion, and fixed-base motion with compensation. Control-input variables and task performance such as the time to translate to the designated hover position, station-keeping position errors, and handling qualities ratings were used as measures. Control force compensation enabled pilot control behavior and performance more similar to that under high- or medium-fidelity motion to some extent only. Control force compensation did not improve overall task performance considering both rotorcraft models at the same time. The control force compensation had effects on the linear model with lighter force gradient, but only a minimal effect on pilots? control behavior and task performance for the UH-60 model, which had a higher force gradient. This suggests that the control force compensation has limited benefits for controllers that have higher stiffness

Klauwgezondheid op stalen roosters ook goed

Bij de standaard uitvoering blijft er veel mest aan de roosterbalken hangen waardoor de emissie hoog is. Door de roosterbalk smaller te maken wordt de mestdoorlaat vergroot en zou de ammoniakemissie lager kunnen zijn

Oriënterende emissiemetingen aan de Comfort Slat Mats voor melkvee = Explorative emission measurements on Comfort Slat Mats for dairy cattle

Emissions of ammonia and methane from the comfort slat mats (a new floor type for dairy cattle) were measured with a dynamic box method. Emissions were reduced up to 50% for ammonia and for 75% for methan

Sturen mestgedrag voorkomt spoelworminfectie niet

Het mestgedrag van biologische vleesvarkens blijkt in een groot hok goed te sturen met de juiste plaatsing van lignest, voerbak, drinkbak en buitenuitloop. Maar ook met het verminderen van het contact met de mest en het schoonspuiten van de uitloop vermindert het aantal spoelworminfecties niet