Conservering van sperma van de Nederlandse zeldzame kippenrassen

Na de eerste drie „inhaalslagen‟ in 2003, 2005 en 2007 is weer een project opgezet om te komen tot het verzamelen van genetisch materiaal van een aantal hanen van zeldzame kippenrassen (inhaalslag 4). Het doel van het project is om (de genetische variatie van) deze (kleine) rassen veilig te stellen in de genenbank. Met de financiële middelen van 2009 kon voor de vierde maal worden gestart met een aantal hanen van rassen, die in 2003, 2005 en 2007 niet voldoende aan bod waren gekomen. In een evaluatie met de Stichting Zeldzame Huisdierrassen en rekening houdend met de reeds aanwezige genenbank collecties zijn zestien rassen geselecteerd waarvan genetisch materiaal is gecryo-conserveerd, te weten het Hollandse Kriel (11), Eikenburger Kriel (5), Sabelpoot Krielen (10), Fries Hoen (2), Hollands Kuifhoen (6), Assendelfter Hoen (6), Drents Hoen (3), Groninger Meeuw (5), Noordhollands Hoen (6), Twents Hoen (3), Chaams Hoen (3), Welsumer (2), Lakenvelder (2), Nederlandse Uilenbaard (2), Barnevelder (4) en het Hollands Hoen (3). Van deze 16 rassen zijn totaal 73 hanen aangevoerd. Vier hanen zijn in de eerste dagen reeds gesneuveld. Van één Eikenburger Kriel haan kon geen sperma worden verkregen. Met de aanvulling van het sperma van de hanen van voornoemde rassen zou de doelstelling kunnen worden bereikt, om van elk ras ca. 800 doses sperma in opslag te hebben van minimaal 10 hanen. In totaal zijn in deze vierde inhaalslag 5534 doses sperma ingevroren en in de genenbank weggezet. De Eikenburger Kriel haalde deze aantallen niet vanwege de te geringe spermaproductie (ruim 200 doses!). Van het Drents Hoen, de Assendelfter Hoen en de Schijndelaar benaderen de aantallen doses sperma de 800

Winning en cryoconservering van sperma van zeldzame Nederlandse konijnenrassen voor de genenbank

In dit rapport wordt beschreven welke activiteiten CGN in samenwerking met de SZH, KLN en individuele fokkers hebben ondernomen om genetisch materiaal van konijnenrassen veilig te stellen in de genenbank. Op basis van literatuur en praktijkervaringen is een protocol voor spermawinning en spermaverwerking (cryoconservering) vastgesteld. Een dergelijk protocol was niet beschikbaar in de Nederlandse bedrijfsmatige konijnenhouderij omdat daar uitsluitend met vers sperma gewerkt wordt en niet met ingevroren sperma. Het rapport eindigt met een beschrijving van de resultaten van de spermawinning

A Dutch MYH7 founder mutation, p.(Asn1918Lys), is associated with early onset cardiomyopathy and congenital heart defects

Background Mutations in the myosin heavy chain 7 (MYH7) gene commonly cause cardiomyopathy but are less frequently associated with congenital heart defects. Methods In th

Animal genetic resources conservation in The Netherlands and Europe: Poultry perspective

Increased global use of highly productive breeds of farm animals has been coupled to loss of genetic diversity in most species. In European countries, various governmental, non-governmental, and private organizations try to preserve genetic diversity of livestock in situ (e.g., by stimulating the use of indigenous, rare breeds by farmers; in nature reserves; or in noncommercial farms). In the case of poultry, maintaining in situ populations of the noncommercial (fancy) breeds largely relies on hobby farmers. In addition to in situ conservation, gene banks are being established for ex situ conservation. In at least 2 countries, France and The Netherlands, there are limited collections of frozen semen of rare poultry breeds. Since 2003, the CGN has started with a more systematic effort to collect, freeze, and store semen of indigenous Dutch poultry breeds. At present, the CGN gene bank contains semen of 11 Dutch rare poultry breeds. Also, CGN has performed research on the methodology for cryopreservation of fowl semen. This recent work was focused on finding a suitable replacement for glycerol, which is contraceptive in the hen, as a cryoprotectant. For reasons of hygiene and sample identification, we favored straw freezing, as opposed to the highly effective pellet freezing method. A significant interaction was found between cooling rate and cryoprotectant concentration. Best post-thaw sperm quality was obtained when combining 0.6 mol of dimethylacetamide/L with a cooling rate of +/- 200 degrees C/min. Inseminations, twice per week with 0.3 billion sperm per insemination resulted in 97 and 88% fertilized eggs with fresh and frozen semen, respectively. In 2005, CGN has used this straw freezing method to extend the collection of poultry semen in the Dutch gene bank

Subglacial till: Formation, sedimentary characteristics and classification

We review the major subglacial till forming processes as presently understood by glacial researchers and define the parameters within which tills are produced and reconcile them with sedimentary end members. Processes of deformation, flow, sliding, lodgement and ploughing coexist at the base of temperate glacier ice and act to mobilize and transport sediment and deposit it as various end members, ranging from glacitectonically folded and faulted stratified material to texturally homogeneous diamicton. The dominance of any one subglacial process varies both spatially and temporally, giving rise to the possibility that a till or complex till sequence contains a superimposed signature of former transportation/deposition at the ice-bed interface. We recommend that, while glacial geologists and geomorphologists should be able to recognize the sedimentary imprints of various subglacial processes, genetic fingerprinting of subglacial tills should be less process-specific and till classification must reflect the range of products encompassed by the subglacial till production continuum. Glacial geologists can presently unequivocally identify: a) glacitectonite (rock or sediment that has been deformed by subglacial shearing/deformation but retains some of the structural characteristics of the parent material); b) subglacial traction till (sediment deposited by a glacier sole either sliding over and/or deforming its bed, the sediment having been released directly from the ice by pressure melting and/or liberated from the substrate and then disaggregated and completely or largely homogenised by shearing); and support the theoretical case for c) melt-out till (sediment released by the melting of stagnant or slowly moving debris-rich glacier ice, and directly deposited without subsequent transport or deformation). Because observations on contemporary glaciers reveal that their beds are most likely to be mosaics of deformation and sliding and warm based and cold based conditions, the patterns of which change temporally and spatially, it is extremely unlikely that subglacial till end members in the geological record will be anything but hybrids produced by the range of processes operative in the subglacial traction zone