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Potentially beneficial traits of Dutch rare breeds for agro-ecological farming Focus on biodiversity in agriculture in the Netherlands is increasing. At the request of The Dutch Rare Breed Society (SZH) a study on traits of Dutch rare and local livestock breeds that may be of added value in agro-ecological agriculture for cattle, sheep, goats and horses was performed. A variety of interviews with experts and farmers of rare breeds was used to identify impacts of these breeds on agricultural ecology, and ways in which these breeds can be used in agroecological farming systems. There are six rare Dutch cattle breeds plus one colour variety, twelve rare Dutch sheep breeds, four rare Dutch goat breeds and four rare Dutch horse breeds in the Netherlands. All holders mentioned specific characteristics of these breeds which make them more suitable for nature-friendly agriculture in comparison to global high production breeds in the Netherlands. Traits such as robustness (being able to cope with changing circumstances), better health, and being able to cope with variations in diet were mentioned for cattle, some sheep and goat breeds. Horse breeds are not used in food production. Rare local horse breeds are mainly characterized by a calmer character. These differences were confirmed by experts. There are opportunities for the use of rare Dutch farm animal breeds in agro-ecological agriculture. Knowledge gaps are identified for investigation in the future, such as high and low input comparisons and research for poultry and swine breeds. Kenmerken van zeldzame rassen die van meerwaarde kunnen zijn in agro-ecologische en andere landbouwsystemen Er is een toenemende aandacht voor biodiversiteit binnen de landbouw in Nederland. In dit onderzoek is op verzoek van De Stichting Zeldzame Huisdierrassen gekeken naar kenmerken van Nederlandse zeldzame en lokale veerassen die van meerwaarde kunnen zijn in agro-ecologische landbouw bij runderen, schapen, geiten en paarden. Hiervoor zijn interviews afgenomen met houders van de zeldzame Nederlandse rassen van deze soorten en met experts op het gebied van genetica, diervoeding, houderij en beleid. In totaal zijn er in Nederland zes zeldzame Nederlandse runderrassen plus één kleurslag, twaalf zeldzame Nederlandse schapenrassen, vier zeldzame Nederlandse geitenrassen en vier zeldzame Nederlandse paardenrassen. Alle houders noemden onderscheidende kenmerken van deze rassen ten opzichte van de meest gebruikte hoogproductieve rassen in Nederland (en wereldwijd). Kenmerken die deze rassen meer geschikt maken voor een natuurvriendelijke landbouw zoals robuustheid (om kunnen gaan met veranderende omstandigheden), betere gezondheid, toekunnen met variatie in kwaliteit en een schraal rantsoen worden met name voor runderrassen en sommige schapen- en geitenrassen genoemd, die deze rassen geschikter maken voor een natuurvriendelijke landbouw. Paardenrassen, die niet in de voedselproductie worden gebruikt, onderscheiden zich vooral door een rustiger karakter. Deze verschillen werden door de experts bevestigd. Er liggen dus zeker kansen voor het gebruik van zeldzame Nederlandse landbouwhuisdierrassen in agro-ecologische landbouw. Meer onderbouwing en onderzoek, ook naar pluimvee- en varkensrassen is echter gewenst.

Deze keer de schijnwerpers op vier andere kuddes Veluwse heideschapen.Die van Ede begrazen al heel lang de Ginkelse en Ederhei. De huidige herders, Aart en Henk van den Brandhof, hebben inrespectievelijk de jaren ‘80 en ‘90 de kuddes overgenomen van hunvader Bart. De kudde van Epe-Heerde begraast al meer dan vijftigjaar de Renderklipen. Bij de oprichting van de kudde van Rheden inde jaren zestig speelde de eigenares van het landgoed Heuvel eenbelangrijke rol.

Meervleermuizen (Myotis dasycneme) vertonen vaak opvallende kale plekken op de rug. Aan de hand van data van meer dan 2200 gevangen meervleermuizen tussen 2003 en 2008 hebben we de mogelijke sociale, eologische en fysiologische oorzaken achter dit fenomeen onderzocht. De aanwezigheid van kale plekken is duidelijk gerelateerd aan de zoogperiode van vrouwtjes. We hebben onderzocht hoe recent het door ons waargenomen patroon is

Tijdens ecologisch veldonderzoek is het vaak nuttig om de leeftijd van een dier te kunnen bepalen. Bij de watervleermuis (Myotis daubentonii) kan de verkleuring van de kinvlek gebruikt worden om de leeftijd van het individu te bepalen. In dit artikel onderzoeken we in hoeverre de verkleuring van de kinvlek ook toepasbaar is voor leeftijdsbepaling bij meervleermuizen (Myotis dasyneme). We concluderen dat de kleur van de kinvlek een betrouwbaar kenmerk is om de leeftijd van de meervleermuis te bepalen

Varens wijken in veel opzichten af van andere potplanten. Ze vormen geen bloemen en de voortplanting is een ingewikkelde zaak. Ook inwendig kennen ze tal van bijzonderheden. Daarom is het des te verwonderlijker dat ze op de bedrijven gewoon tussen andere groene planten kunnen worden geteeld.

Infectious diseases in farm animals are of major concern because of animal welfare, production costs, and public health. Farms undergo huge economic losses due to infectious disease. The costs of infections in farm animals are mainly due to production losses, treatment of infected animals, and disease control strategies. Control strategies, however, are not always successful. Selective breeding for the animals that can mount a defence against infection could therefore be a promising approach. Defensive ability of an animal has two main mechanisms: resistance (ability to control the pathogen burden) and tolerance (ability to maintain performance when pathogen burden increases). When it is difficult to distinguish between resistance and tolerance, defensive ability is measured as resilience that is the ability to maintain performance during a disease outbreak regardless of pathogen burden. Studies have focused on the genetics of resistance and resilience with little known about the genetics of tolerance and its relationship with resistance and resilience. The objectives of this thesis were to: 1) estimate the genetic variation in resistance, tolerance, and resilience to infection in order to assess the amenability of these traits for selective breeding in farm animals, 2) estimate the genetic correlation between resistance, tolerance and resilience and 3) detect genomic regions associated with resistance, tolerance, and resilience. In chapter 2, we studied the variation among sows in response to porcine reproductive and respiratory syndrome (PRRS). First a statistical method was developed to detect PRRS outbreaks based on reproduction records of sows. The method showed a high sensitivity (78%) for disease phases. Then the variation of sows in response to PRRS was quantified using 2 models on the traits number of piglets born alive (NBA) and number of piglets born dead (LOSS): 1) bivariate model considering the trait in healthy and disease phases as different traits, and 2) reaction norm model modelling the response of sows as a linear regression of the trait on herd-year-week estimates of NBA. Trait correlations between healthy and disease phases deviated from unity (0.57±0.13 – 0.87±0.18). The repeatabilities ranged from 0.07±0.027 to 0.16±0.005. The reaction norm model had higher predictive ability in disease phase compared to the bivariate model. In chapter 3 we studied 1) the genetic variation in resistance and tolerance of sheep to gastrointestinal nematode infection and 2) the genetic correlation between resistance and tolerance. Sire models on faecal nematode egg count (FEC), IgA, and pepsinogen were used to study the genetic variation in resistance. Heritability for resistance traits ranged from 0.19±0.10 to 0.59±0.20. A random regression model was used to study the reaction norm of sheep body weight on FEC as an estimate of tolerance to nematode infection. We observed a significant genetic variance in tolerance (P

Deze keer de schijnwerpers op vier andere kuddes Veluwse heideschapen.Die van Ede begrazen al heel lang de Ginkelse en Ederhei. De huidige herders, Aart en Henk van den Brandhof, hebben inrespectievelijk de jaren ‘80 en ‘90 de kuddes overgenomen van hunvader Bart. De kudde van Epe-Heerde begraast al meer dan vijftigjaar de Renderklipen. Bij de oprichting van de kudde van Rheden inde jaren zestig speelde de eigenares van het landgoed Heuvel eenbelangrijke rol.

Voor velen van u zal het herkenbaar zijn: verknocht zijn aan een dier om zijn of haar uiterlijk en gedrag. Juist deze kenmerken die horen bij een bepaald ras, wilt u behouden en optimaliseren wanneer u gaat fokken. Verstandig fokken binnen een ras vraagt naast enige kennis van erfelijkheidsleer om het systematisch nalopen van een aantal foktechnische stappen. Deze stappen, die samen het fokprogramma bepalen, komen vanaf dit nummer van Zeldzaam Huisdier in 2015 aan bod.

Khaw, HL. (2014). Cooperative and uniform fish? Social interactions and variability in live body weight in the GIFT strain (Nile tilapia, Oreochromic niloticus) in Malaysia. PhD thesis, Wageningen University, the Netherlands. Social interactions are present everywhere in the living world. Such social interactions may lead to indirect genetic effects (IGE), which are heritable effects of an individual on trait values of the other individuals its interacts with. IGEs may affect the direction and magnitude of response to selection in breeding programs. Moreover, social interactions may affect variability of traits. In aquaculture, competition for resources inflates size variation within populations. In this thesis, we used the Genetically Improved Farmed Tilapia (GIFT; Oreochromis niloticus) strain to investigate the genetic basis for social interactions and variability in harvest weight for tropical finfish. Social interaction experiments were established for quantifying the genetic and non-genetic indirect effects on harvest weight in the GIFT strain. We found evidence for IGEs on harvest weight, and a negative direct-indirect genetic correlation, which suggesting heritable competitive interactions for harvest weight in GIFT. Hence, breeding schemes may need to be adapted to avoid an increase in competition. A stochastic simulation study was conducted to examine the effect of BLUP selection on the rate of inbreeding for socially affected traits. The rates of inbreeding for scenarios with IGEs were greater than for scenarios without IGE. Therefore, with IGEs there is a greater need for a selection algorithm that restricts the increase of mean kinship. In aquaculture industry, there is a wide range of commercial production environments, which may leads to genotype by environment (GxE) interaction, for example due to differential social interactions. The GIFT fish were tested in ponds and cages to study the GxE interaction. The genetic correlations between environments (0.73 to 0.85, for harvest weight and body measurements) indicate little GxE-interaction. The data collected from the social interaction experiments were also used to investigate the presence of genetic variation in uniformity for harvest weight. The genetic coefficient of variation for standard deviation of harvest weight (0.17) shows that uniformity of harvest weight is heritable and can be increased by selective breeding. In the General Discussion of this thesis, the uniformity study was extended to incorporate IGE. The result indicates that more cooperative fish are not necessary more uniform for harvest weight. Overall, our results suggest that genetic improvement in fish breeding programs can be increased by accounting for social interactions.

Exploiting wild relatives of S. lycopersicum for quality traitsAna Marcela Víquez ZamoraTomatoes are consumed worldwide and became a model for crop plant research.A part of the research aims at expanding genetic diversity in tomato; this can be done by incorporating useful genes found in wild germplasm. In this thesis we focused on exploring the variation between commercial tomatoes and accessions of wild relatives. Especially, we focused on the speciesSolanumpimpinellifolium. We explored the genome and the metabolome of accessions ofS. pimpinellifoliumand several varieties ofS. lycopersicum. Finally a crossing population between the species was genetically analyzed. Clear differences were identified. We found genome regions related to differences between round and cherry tomatoes, TYLCV resistance, flavour and the phenylpropanoid pathway.S. pimpinellifoliumcertainly harbours useful genetic variability that can be (re-) introduced in tomato. Our results give an insight in the physical positions of metabolite related QTLs that can be used by breeders to exploitS. pimpinellifolium to improve tomato quality.

Khaw, HL. (2014). Cooperative and uniform fish? Social interactions and variability in live body weight in the GIFT strain (Nile tilapia, Oreochromic niloticus) in Malaysia. PhD thesis, Wageningen University, the Netherlands. Social interactions are present everywhere in the living world. Such social interactions may lead to indirect genetic effects (IGE), which are heritable effects of an individual on trait values of the other individuals its interacts with. IGEs may affect the direction and magnitude of response to selection in breeding programs. Moreover, social interactions may affect variability of traits. In aquaculture, competition for resources inflates size variation within populations. In this thesis, we used the Genetically Improved Farmed Tilapia (GIFT; Oreochromis niloticus) strain to investigate the genetic basis for social interactions and variability in harvest weight for tropical finfish. Social interaction experiments were established for quantifying the genetic and non-genetic indirect effects on harvest weight in the GIFT strain. We found evidence for IGEs on harvest weight, and a negative direct-indirect genetic correlation, which suggesting heritable competitive interactions for harvest weight in GIFT. Hence, breeding schemes may need to be adapted to avoid an increase in competition. A stochastic simulation study was conducted to examine the effect of BLUP selection on the rate of inbreeding for socially affected traits. The rates of inbreeding for scenarios with IGEs were greater than for scenarios without IGE. Therefore, with IGEs there is a greater need for a selection algorithm that restricts the increase of mean kinship. In aquaculture industry, there is a wide range of commercial production environments, which may leads to genotype by environment (GxE) interaction, for example due to differential social interactions. The GIFT fish were tested in ponds and cages to study the GxE interaction. The genetic correlations between environments (0.73 to 0.85, for harvest weight and body measurements) indicate little GxE-interaction. The data collected from the social interaction experiments were also used to investigate the presence of genetic variation in uniformity for harvest weight. The genetic coefficient of variation for standard deviation of harvest weight (0.17) shows that uniformity of harvest weight is heritable and can be increased by selective breeding. In the General Discussion of this thesis, the uniformity study was extended to incorporate IGE. The result indicates that more cooperative fish are not necessary more uniform for harvest weight. Overall, our results suggest that genetic improvement in fish breeding programs can be increased by accounting for social interactions.

Exploiting wild relatives of S. lycopersicum for quality traitsAna Marcela Víquez ZamoraTomatoes are consumed worldwide and became a model for crop plant research.A part of the research aims at expanding genetic diversity in tomato; this can be done by incorporating useful genes found in wild germplasm. In this thesis we focused on exploring the variation between commercial tomatoes and accessions of wild relatives. Especially, we focused on the speciesSolanumpimpinellifolium. We explored the genome and the metabolome of accessions ofS. pimpinellifoliumand several varieties ofS. lycopersicum. Finally a crossing population between the species was genetically analyzed. Clear differences were identified. We found genome regions related to differences between round and cherry tomatoes, TYLCV resistance, flavour and the phenylpropanoid pathway.S. pimpinellifoliumcertainly harbours useful genetic variability that can be (re-) introduced in tomato. Our results give an insight in the physical positions of metabolite related QTLs that can be used by breeders to exploitS. pimpinellifolium to improve tomato quality.