Comparison of fresh and ensiled white and red clover added to ryegrass on energy and protein utilization of lactating cows

Two respiratory chamber experiments were conducted with dairy cows to compare metabolizable energy and protein utilization when feeding white or red clover with ryegrass. In experiment 1, fresh ryegrass was mixed with fresh white (WF) or red clover (RF) (60/40, on dry matter (DM) basis). Experiment 2 involved similar mixed diets in ensiled form (WS and RS, respectively), and two ryegrass silage diets, without (GS) or with supplementary maize gluten (GS+). Barley was supplemented according to requirements for milk production. Voluntary forage DM intake remained unaffected in experiment 1 and was higher (P<0·01) in experiment 2 for WS than for GS and GS+(128 v. 98 and 106 g/kg M0·75). Within experiments, no treatment effects occurred for apparent nutrient digestibilities, milk yield, and composition. Protein utilization (milk-N/N-intake) was numerically lower on all clover-based diets (0·24 to 0·25) versus GS (0·29). With added maize gluten (GS+), protein utilization decreased to 0·23, indicating that ryegrass silage (plus barley) alone provided sufficient metabolizable protein. Consequently, higher (P<0·01) urinary energy losses occurred in GS+ compared with GS, despite similar metabolizable energy intakes, and a trend for the highest plasma urea levels was found for GS+ cows (7·59 mmol/l; P<0·1). Overall, this study illustrates that the white and red clovers investigated were equivalent in energy and protein supply, also in comparison to the ryegrass. It remains open whether these forage legumes, when supplemented to a moderate-protein ryegrass, would have contributed to metabolizable protein supply or would have merely increased metabolic nitrogen loa

Effect of Red and White Clover Added to a Rye Grass-Based Diet on Intake, Fibre Digestion and Methane Release of Dairy Cows

Forage legumes like white and red clover are widely grown in association with grass, with the intention to improve the quality of grass-based diets. However little is known about the effect of either white or red clover added to a grass-based diet on methane release, and existing studies are not conclusive. The objective of this study, applying the respiratory chamber technique, was to determine the effect of red and white clover added to a rye grass-based diet on intake, fibre digestion and methane release of dairy cows

Effects of a latency period between pre-stimulation and teat cup attachment and periodic vacuum reduction on milking characteristics and teat condition in dairy cows

The goal of the present study was to examine the suitability of a short pre-stimulation (P) for 15s followed by a latency period (L) of 30s before cluster attachment for machine milking. In addition we tested the effect of a periodic reduction of the vacuum under the teat (VR) during the massage phase from 43kPa to 12-15kPa on milking characteristics and teat tissue condition. The study was carried out in 9 cows in a cross-over design. Animals were milked twice daily, and each of the 4 treatment combinations was used for six subsequent milkings (P+L vs. continuous P, and standard pulsation vs. VR, respectively). Milk flow was recorded during all experimental milkings. Longitudinal ultrasound cross sections of the teat were performed by B-mode ultrasound after the last milking of each treatment at 0, 5, and 15min after the end of milking, respectively. None of the evaluated milking characteristics (total milk yield, main milking time, peak flow rate, average milk flow) differed between treatments. Teat measures as obtained by ultrasound cross sections showed no significant difference if individual treatments were compared at the three time points individually. However, teat wall thickness (TWT) tended to be smaller in VR vs. non-VR treatments at 5min after milking (P=0·05). In conclusion, teat preparation consisting of a short stimulation followed by a latency period represents a similarly efficient pre-stimulation as a continuous pre-stimulation. VR seems to reduce the load on the teat tissue during milking and thus reduces the development of oedema and hence a less pronounced increase of TWT while milking characteristics are similar with or without V

Ontwikkelingen in het grondgebruik in Oost-Nederland en de West-Duitse grensregio: tijdreeksen grondgebruik van 1850 tot 1990

Voor de periode 1850-1990 zijn voor de regio Midden- en Oost-Nederland en het grensgebied van Duitsland tijdreeksen met historisch grondgebruik ontwikkeld. De gegevens hiervoor zijn ontleend aan landsdekkende topografische kaarten die vanaf 1850 zijn verschenen. Er zijn 5 tijdstappen onderscheiden: 1850, 1900, 1930, 1960 en 1990. De Nederlandse en Duitse kaarten zijn gescand en geometrisch gecorrigeerd naar het RD-stelsel. Met een semi-automatische classificatie zijn van de gescande kaarten de kleuren omgezet naar 10 klassen met grondgebruik. Voor Duitsland zijn voor de periode 1900 en 1930 alleen zwart-wit kaarten beschikbaar. Deze zijn grotendeels handmatig bewerkt. De volgende vormen van grondgebruik zijn onderscheiden: grasland, akker/kale grond, heide en hoogveen, loofbos, naaldbos, bebouwd gebied en wegen, water, rietmoeras, stuifduinen en zandplaten en overig. Het resultaat is een tijdserie van GIS bestanden met dominant grondgebruik op basis van 50 meter grids. Validatie laat zien dat de nauwkeurigheid van de bestanden circa 95-99% bedraagt. De tijdreeks voor dit gebied is onderdeel van de ontwikkeling van een reeks landsdekkende databestanden met Historisch Grondgebruik vanaf 1800 op basis van 50 meter grids

Ontwikkeling emissiemanagementsysteem grondgebonden teelt; de lysimeter en drainmeter

Het hoofddoel van het project ‘Glastuinbouw Waterproof, grondgebonden’ was het ontwikkelen van een aantal middelen voor telers van grondgebonden teelten, waarmee zij emissiedoelstellingen kunnen halen. De leidende gedachte hierbij is dat een gesloten waterkringloop zoals toegepast bij substraatteelten onhaalbaar is. Emissiereductie zal vooral via het waterspoor behaald moeten worden en daarom is een brongerichte aanpak, de irrigatie afgestemd op de evapotranspiratie, het meest effectief. Het project omvatte in de eerste plaats het ontwikkelen en combineren van een aantal technische hulpmiddelen en in de tweede plaats het installeren en testen in de praktijk. In dit rapport worden de lysimeter en de bijbehorende drainmeter besproken

The HII Region KR 140: Spontaneous Formation of a High Mass Star

We have used a multiwavelength data set from the Canadian Galactic Plane Survey (CGPS) to study the Galactic HII region KR 140, both on the scale of the nebula itself and in the context of the star forming activity in the nearby W3/W4/W5 complex of molecular clouds and HII regions. From both radio and infrared data we have found a covering factor of about 0.5 for KR 140 and we interpret the nebula as a bowl-shaped region viewed close to face on. Extinction measurements place the region on the near side of its parent molecular cloud. The nebula is kept ionized by one O8.5 V(e) star, VES 735, which is less than a few million years old. CO data show that VES 735 has disrupted much of the original molecular cloud for which the estimated mass and density are about 5000 $M_{\odot}$ and 100 cm$^{-3}$, respectively. KR 140 is isolated from the nearest star forming activity, in W3. Our data suggest that KR 140 is an example of spontaneous (i.e., non-triggered) formation of, unusually, a high mass star.Comment: 46 pages; includes 15 figures; accepted by the Ap

Ontwikkeling emissiemanagementsysteem grondgebonden teelt; bodemvochtsensoren en modulaire opbouw van het systeem

‘Glastuinbouw Waterproof - Grondgebonden’ heeft een modulair emissiemanagementsysteem opgeleverd waarmee telers hun water en meststoffen gebruik kunnen optimaliseren naar een goed teeltresultaat en een minimale emissie. Kern van dit systeem is de lysimeter, waarmee dagelijks de werkelijke drainhoeveelheid gevolgd kan worden. Door bemonstering en analyse van de drain wordt de emissie van meststoffen inzichtelijk. Het systeem bevat naast de lysimeter, een drainmeter, bodemvochtgehalte sensoren en een beslissingsondersteunend systeem met modellen voor gewasverdamping en watertransport in de bodem. Telers kunnen kiezen welke modules ze naast de lysimeter willen toepassen, en ook hoe ze informatie willen inzien, op hun klimaatcomputer of via een externe dienst zoals Letsgrow.com. Bodemvochtgehalte sensoren zijn toegepast en geëvalueerd bij negen praktijktelers. Op basis van de resultaten is een specifi catie opgesteld voor de beste keus, een marktverkenning uitgevoerd, een handleiding geschreven voor het gebruik, en zijn twee typen robuuste sensoren gekozen en in een pilot experiment getest. Met de lysimeter kunnen telers ervaring opdoen, en zo hun strategie op langere termijn aanpassen. Met sensoren kunnen ze trends in bodemvocht volgen en hun dagelijkse gietbeurten daarop aanpassen. Modellen geven de mogelijk om anticiperend te sturen en water te geven naar behoefte van de plant, gericht op voorkomen van emissies

Improving air quality in metropolitan Mexico City : an economic valuation

Mexico City has for years experienced high levels of ozone and particulate air pollution. In 1995-99 the entire population of the Mexico City metropolitan area was exposed to annual average concentrations of fine particulate pollution (particulates with a diameter of less than 10micrometers, or PM10) exceeding 50 micrograms per cubic meter, the annual average standard in both Mexico and the United States. Two million people were exposed to annual average PM10 levels of more than 75 micrograms per cubic meter. The daily maximum one-hour ozone standard was exceeded at least 300 days a year. The Mexico Air Quality Management Team documents population-weighted exposures to ozone and PM10 between 1995 and 1999, project exposures in 2010, and computes the value of four scenarios for 2010: A 10 percent reduction in PM10 and ozone. A 20 percent reduction in PM10 and ozone. Achievement of ambient air quality standards across the metropolitan area. A 68 percent reduction in ozone and a 47 percent reduction in PM10 across the metropolitan area. The authors calculate the health benefits of reducing ozone and PM10 for each scenario using dose-response functions from the peer-reviewed literature. They value cases of morbidity and premature mortality avoided using three approaches: Cost of illness and forgone earnings only (low estimate). Cost of illness, forgone earnings, and willingness to pay for avoided morbidity (central case estimate). Cost of illness, forgone earnings, willingness to pay for avoided morbidity, and willingness to pay for avoided mortality (high estimate). The results suggest that the benefits of a 10 percent reduction in ozone and PM10 in 2010 are about $760 million (in 1999 U.S. dollars) annually in the central case. The benefits of a 20 percent reduction in ozone and PM10 are about$1.49 billion annually. In each case the benefits of reducing ozone amount to about 15 percent of the total benefits. By estimating the magnitude of the benefits from air pollution control, the authors provide motivation for examining specific policies that could achieve the air pollution reductions that they value. They also provide unit values for the benefits from reductions in ambient air pollution (for example, per microgram of PM10) that could be used as inputs into a full cost-benefit analysisof air pollution control strategies.Montreal Protocol,Public Health Promotion,Global Environment Facility,Air Quality&Clean Air,Health Monitoring&Evaluation,Montreal Protocol,Air Quality&Clean Air,Health Monitoring&Evaluation,Global Environment Facility,Transport and Environment