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The invention relates to methods for pregnancy and non-pregnancy testing and also relates to methods allowing determination of proper insemination time to establish pregnancy. The invention provides method to determine whether an inseminated female mammal is pregnant prior to a point in time at which said mammal would be expected to ovulate if non- pregnant, said method comprising taking a biological sample from said mammal prior to said point in time and testing said sample for the presence of a multiple pregnancy marker pattern (MPMP). It is preferred that said sample is tested for the relative expression of progesterone and of at least one marker selected from a group of marker proteins that each contribute to a significantly differential marker expression pattern related to the status pregnancy and is tested to determine whether said mammal is non-pregnant and may be re- inseminated.

The objective of this study is to investigate possible biological effects of radiofrequency electromagnetic fields (RF-EMF) as used in modern wireless telecommunication in a wellcontrolled experimental environment using chicken embryo development as animal model. Chicken eggs were incubated under continuous experimental exposure to GSM (1.8 GHz), DECT (1.88 GHz), UMTS (2.1 GHz), and WLAN (5.6 GHz) radiation, with the appropriate modulation protocol, using a homogeneous field distribution at a field strength of approximately 3 V/m, representing the maximum field level in a normal living environment. Radiation-shielded exposure units/egg incubators were operating in parallel for exposed and control eggs in a climatized homogeneous environment, using 450 eggs per treatment in three successive rounds per treatment. Dosimetry of the exposure (field characteristics and specific absorption rate) were studied. Biological parameters studied included embryo death during incubation, hatching percentage, and various morphological and histological parameters of embryos and chicks and their organs, and gene expression profiles of embryos on day 7 and day 18 of incubation by microarray and qPCR. No conclusive evidence was found for induced embryonic mortality or malformations by exposure to the used EMFs, or for effects on the other measured parameters. Estimated differences between treatment groups were always small and the effect of treatment was not significant. In a statistical model that ignored possible interaction between rounds and exposure units, some of the many pairwise comparisons of exposed versus control had P-values lower than 0.05, but were not significant after correction for multiple testing. Bioelectromagnetics. 38:186–203, 2017.

Throughout the world, male chicks from layer breeds are killed just after hatching, as they are not profitable as regards the production of meat. The Dutch and European parliaments have insisted on research into possible alternatives to the killing of day-old chicks. In the present study we have investigated Dutch public opinion on the acceptability of these alternatives by means of discussions in socalled focus groups and via a public survey through computer-aided personal interviews (CAPI). To inform the participants about the subject, a film was made to explain the current practice and introduce a number of technological alternatives that would prevent development of male embryos, as well as the possibility of creating a ‘dual-purpose chicken’ that would allow male chicks to be used for meat production. The topics addressed in the study included the willingness of participants to pay a premium for eggs and chicken meat, were it necessary to prevent killing of male chicks. Focus-group discussions showed that many participants were unaware of the current practise of killing male chicks, and were shocked by this practice. However, once informed, the participants seemed able to take various considerations into account and rank the alternatives. The alternatives ‘looking into the fresh egg (to determine sex of the egg and not incubate male eggs)’, and ‘dual-purpose chickens’ scored best out of all the possible alternatives, and higher than maintaining the current practice. ‘Influencing the laying hens such that they produce fewer male eggs’ scored the same as maintaining the current practice. The use of ‘genetic modification to facilitate looking into the fresh egg’ scored only slightly lower than maintaining the current practice. Alternatives whereby developing male embryos die, or are killed, scored lower than maintaining the current practice. Keywords: animal ethics, animal welfare, chicks, killing, laying hens, public opinion

Female birds have been shown to manipulate offspring sex ratio. However, mechanisms of sex ratio bias are not well understood. Reduced feed availability and change in body condition can affect the mass of eggs in birds that could lead to a skew in sex ratio. We employed feed restriction in laying chickens (Gallus gallus) to induce a decrease in body condition and egg mass using 45 chicken hens in treatment and control groups. Feed restriction led to an overall decline of egg mass. In the second period of treatment (Days 9–18) with more severe feed restriction and a steeper decline of egg mass, the sex ratio per hen (proportion of male eggs) had a significant negative association with mean egg mass per hen. Based on this association, two groups of hens were selected from feed restriction group, that is, hens producing male bias with low egg mass and hens producing female bias with high egg mass with overall sex ratios of 0.71 and 0.44 respectively. Genomewide transcriptome analysis on the germinal disks of F1 preovulatory follicles collected at the time of occurrence of meiosis-I was performed. We did not find significantly differentially expressed genes in these two groups of hens. However, gene set enrichment analysis showed that a number of cellular processes related to cell cycle progression, mitotic/meiotic apparatus, and chromosomal movement were enriched in female-biased hens or high mean egg mass as compared with male-biased hens or low mean egg mass. The differentially expressed gene sets may be involved in meiotic drive regulating sex ratio in the chicken.

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.

The aim of this study is to develop an accurate, fast, cheap, and reliable test to detect pregnancy before day 35 on the basis of markers in milk. The ultimate goal is to have a method that can be implemented in a practical setting. Doel van dit project is het ontwikkelen van een accurate, snelle, goedkope en betrouwbare test om vóór dag 35 na inseminatie dracht van melkkoeien te kunnen vaststellen aan de hand van merkers in de melk. Uiteindelijk doel is te komen tot een toepasbare methode voor de praktijk.

In de periode 2001-2012 is in een aantal acties genetisch materiaal van Nederlandse schapen- en geitenrassen opgenomen in de genenbank voor landbouwhuisdieren. In totaal zijn er ruim 34.000 doses rammen- en bokkensperma van 12 rassen opgeslagen in de genenbank. In dit rapport wordt beschreven welke activiteiten het Centrum voor Genetische Bronnen Nederland in de periode 2001-2012 heeft ondernomen om genetisch materiaal van schapen- en geitenrassen veiliig te stellen in de genenbank. De eerste actie vond plaats in 2001-2002, net na de MKZ-crisis, die duidelijk maakte dat er een reëel gevaar is dat een groot deel van de heideschapen bij een dergelijke dierziekte kan verdwijnen. Na deze eerste actie is het aantal doses sperma van diverse schapen- en geitenrassen verder uitgebreid in de periode 2003-2012. Naast de heideschaaprassen zijn het Melkschaap, de Zwartbles, de Blauwe Texelaar, de Nederlandse Landgeit en de Nederlandse Bonte en Witte geit toegevoegd aan de genenbank.

Many wild equids are at present endangered in the wild. Concurrently, increased mechanization has pushed back the numbers of some old native horse breeds to levels that are no longer compatible with survival of the breed. Strong concerns arose in the last decade to preserve animal biodiversity, including that of rare horse breeds. Genome Resource Banking refers to the cryostorage of genetic material and is an approach for ex situ conservation, which should be applied in combination with in situ conservation programmes. In this review, we propose that, owing to the great reproductive similarity among the different members of the genus Equus, the domestic horse can be used to optimize cryopreservation and embryo production protocols for future application in wild equids. We will give this hypothesis a scientific underpinning by listing successful applications of epididymal sperm freezing, embryo freezing, intracytoplasmic sperm injection, oocyte vitrification and somatic cell nuclear transfer in domestic horses. Some ART fertilization methods may be performed with semen of very low quality or with oocytes obtained after the death of the mare.