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Enteric methane (CH4) is one of the main greenhouse gases emitted in livestock production systems with ruminants. Among the options to reduce such emissions, animal genetics is one of the factors that is taking relevance in recent years. The aim of the present study was to assess the emission of enteric CH4 in dairy cows with different genetic backgrounds. Sixteen cows belonging to the following three genetic groups were selected for this study: seven F1 (50% Jersey × 50% Gyr), five Triple cross (50% Jersey × 31% Holstein × 19% Sahiwal) and four Jersey. Enteric CH4 emissions were measured in all cows for 15 months, at the middle of each month, using the SF6 technique. Enteric CH4 emissions did not differ (p > 0.05) among genetic groups, although it varied with the stage of lactation, due to differences in milk yield and dry matter intake (DMI). Pasture DMI and the intensity of CH4 emissions (g kg−1 DMI) differed (p < 0.05) between dry and lactating cows, with higher DMI in the lactation period, while CH4 emission intensity was higher for dry cows. Cows with the highest proportion of Bos taurus genes presented a higher annual mean methane conversion factor (Ym), with 7.22, 7.05 and 5.90% for the Triple cross, purebred Jersey and F1, respectively. In conclusion, non-significant differences in enteric CH4 emissions and Ym were detected among dairy cows with different genetic backgrounds. However, F1 cows tended to show lower enteric CH4 emission and Ym, compared to those with more Bos taurus genes.

Two categories of beef production exist; i.e. (i) purebred animals from a beef sire and a beef dam and (ii) crossbred animals from a beef sire and a dairy dam. For the purebred beef production, there is a growing interest to include behavior and type traits in the breeding goal. Heritabilities for behavior traits, estimated using subjective data scored by farmers, range from 0.02 to 0.19. Heritabilities for type traits range from 0.02 to 0.35. Results show that there are good opportunities to implement selection for behavior traits using a simple on-farm recording system to allow collection of large data set, and for type traits in Charolais. A genome-wide association study detected 16 genomic regions with small effect on behavior and type traits. This suggests that behavior and type traits are influenced by many genes each explaining a small part of the genetic variance. The two main dairy breeds mated to Charolais sires for crossbred beef production in France are Montbéliard and Holstein. The genetic correlation between the same trait measured on Montbéliard x Charolais and on Holstein x Charolais was 0.99 for muscular development, 0.96 for birth weight; and 0.91 for calving difficulty, 0.80 for height, and 0.70 for bone thinness. Thus, for these last three traits, results show evidence for re-ranking of Charolais sires depending on whether they are mated to Montbéliard or Holstein cows. When using genomic prediction, the Montbéliard x Charolais and Holstein x Charolais populations could be combined into a single reference population to increase size and accuracy of genomic prediction. Results indicate that the higher the genetic correlation is between the two crossbred populations, the higher the gain in accuracy is achieved when combining the two populations into a single reference. The selection of Charolais sires to produce purebred or crossbred animals is made through distinct breeding programs. An alternative could be to combine selection into one breeding p

Video recording about breeding and genetics

Lopes, M.S. (2016). Genomic selection for improved crossbred performance. PhD thesis, Wageningen University, the Netherlands With the implementation of genomic selection in pig breeding, the genetic progress in purebred populations is expected to increase up to 55% compared to traditional selection based on pedigree information. However, as most of the animals in the pork production system are crossbreds, the increase in genetic progress in purebreds will only be observed on production farms if this progress is expressed in the performance of crossbreds. The main aim of this thesis was to evaluate different models based on genomic information which can be applied to improve performance of crossbred animals. Another aim was to gain insight into genetic architecture of (complex) traits and to investigate how selection history has influenced haplotype patterns of current commercial pigs. This thesis shows that by going beyond traditional genomic selection models, phenotypes can be predicted more accurately. Therefore, these improved models should be considered to improve crossbred performance. Further, this thesis provides important insights into the genetic architecture of the evaluated (complex) traits and also shows evidence that human-driven introgression and selection have shaped the genome of current commercial pig breeds. The research presented in this thesis was performed using data from pigs and the discussion on the practical application of results was focused on pig breeding. The results are relevant for all livestock species where crossbreeding is applied.

Securing a sufficiently large set of genotypes and phenotypes can be a limiting factor when implementing genomic selection. This limitation may be overcome by combining data from multiple populations or by using information of crossbred animals. The research described in this thesis characterized linkage disequilibrium (LD) patterns in different pig populations and evaluated whether the consistency of LD between populations allows us to make predictions about the performance of genomic selection when multiple populations are included in the prediction and/or validation datasets. In chapter 2 I evaluated the persistence of LD and patterns of LD decay of pure and crossbred pig populations using real data that was representative of the crossbreeding structure of pig production. The persistence of phase between the crosses and their parental populations was high, indicating that similar marker effects might be expected across these populations. Across the purebred populations the persistence of phase was low therefore higher density panels should be used to have the same marker-QTL associations across these populations. In chapter 3, the well-known nonlinear model developed by Sved (1971) was compared against a an alternative, loess regression, to describe LD decay. The loess regression model was found to be less influenced by the lack of residual normality, independence and homogeneity of variance than the nonlinear regression model. The loess regression model resulted in more reliable LD predictions and can be used to formally compare the LD decay curves between populations. Chapter 4 showed the utility of different reference sets (across- and multi-population) for the prediction of genomic breeding values, as well as the potential of using crossbred performance in genomic prediction. None of the accuracies obtained using across-population, or multi-population genomic prediction, nor the accuracies obtained using crossbred data, followed the expectations based on LD t

With Montbeliarde, Holstein Friesian, Brown Swiss and MRI blood in his pedigree, Woeste Polder Reladon is immediately interesting. And interest in cross-bred bulls appears to be increasing in many other countries.

Nieuwe tulpen komen er elk jaar genoeg, maar zijn ze ook allemaal goed, of beter dan wat er is. Die vragen stonden centraal tijdens een themabijeenkomst van LTO Groeiservice, die op vrijdag 21 januari 2011 op de marktbroeishow van Proeftuin Zwaagdijk werd gehouden.

KI Fabroca heeft als eerste de focus in het witblauwras gelegd op vreemde bloedlijnen, hoogtemaat en gewicht. De komende jaren gaat eigenaar Benoit Cassart de boer op met een zelf ontwikkelde lineaire beoordeling van de stieren. Eigen nakomelingenonderzoek staat in de steigers.

Het hele jaar door is in de KAVB-keuringszaal een zeer gevarieerde hoeveelheid bol- en knolgewassen te zien. In de rubriek Nauwkeurig wordt op een van die gewassen ingegaan. Dit keer de rol van Amaryllis belladonna als kruisingsouder.

Fokkerijorganisaties bevestigen dat de vraag naar sperma van rassen als Brown Swiss, Scandinavisch Roodbont, Montbéliarde en Fleckvieh toeneemt. Vooral op grote bedrijven waar men op zoek is naar een probleemloze koe stijgt de interesse voor het inkruisen. Zowel in Nederland als in België zijn er bedrijven die zich verdiept hebben in crossbreeding waarbij het verbeteren van de gebruikskenmerken als belangrijkste reden wordt opgegeven.

This thesis deals with the identification of genes controlling intramuscular fat and backfat thickness. Markers linked to quantitative trait loci (QTL) for these traits in the cross between Meishan x Large White breeds will lead to the identification of the underlying genetic causes. A whole-genome scan revealed significant evidence for five QTLs affecting body composition, of which four were imprinted. Additional markers were typed in this cross to further investigate the regions on pig chromosome (SSC) 2, SSC4 and SSC7. Imprinting analysis revealed a genome wise significant paternally expressed QTL on SSC2. A radiation hybrid (RH) map was constructed for SSC2. Comparison of the porcine RH map with homologous human chromosomes identified four conserved segments between SSC2 and HSA11, HSA19, and HSA5. To improve the existing comparative map for SSC2 and increase the gene density on this chromosome, a porcine BAC library was screened. Sequences from the BACs were compared with sequences in the nucleotide databases to identify homology with other mammalian sequences. For the investigation of the borders of the conserved segments between SSC2 and HSA11 genes located on HSA11 were mapped to SSC2. This resulted in refinement of the borders of the conserved segments and in the detection of a new rearrangement in the comparative map between HSA11 with the porcine genome. Through the use of radiation hybrid maps that include both Type I and II markers, homologous chromosomal locations for QTL of specific traits can be identified in other species. The conservation of genome organisation between pig, man and mouse makes it possible to take advantage of genetically well-characterised species for the selection of candidate genes for the imprinted QTL for backfat thickness on SSC2. Human obesity research can help to determine the direction and give clues for further porcine fat trait related genetic research, but emphasis should be on better understanding of the fat traits in p

Uitleg over de geschiedenis van de bijenteelt (veredeling en selectie) in West-Europa, en de twee teeltrichtingen, rassenteelt of lijnteelt en combinatieteelt (kruisen van rassen). Als voorbeelden van beide richtingen de rassenteelt in Duitsland met de Carnicabij en de combinatieteelt met de Buckfastbij. Ook wordt ingegaan op de praktijk van de teelt, de meest toegepaste teeltprogramma's en teeltschema's (raszuivere teelt; lijnteelt; kruisingsteelt; combinatieteelt) in West-Europa, en de hybridenteelt in Noord-Amerika

Plant Research International doet onderzoek naar mogelijkheden om de biologische zaaiuienteelt te verbeteren. Speerpunten vormen de veredeling op ziekteresistentie (tegen valse meeldauw, Peronospora destructor, en bladvlekkenziekte, Botrytis squamosa), en op een forser wortelstelsel om de stikstofbenutting en droogtegevoeligheid te verbeteren (de wilde verwanten Allium fistulosum en A. roylei spelen daarbij een rol). In een apart kader worden cijfers gegeven voor de omvang, opbrengsten en saldo's van biologisch en gangbaar geteelde zaaiuien in Nederland

Purebred and two-breed cross (F1) boars were mated to F1 females to produce all possible three- and four-breed cross pigs involving the Duroc, Yorkshire, Landrace and Spotted breeds. Individual post-weaning average daily gain (ADG), age at 100 kg (AGE) and probed backfat thickness at 100 kg (BE) data were collected on 3,456 pigs. A total of 213 pens with an average of 15.58 pigs per pen was evaluated for post-weaning feed-to-gain ratio (F/G) and average daily feed consumption (ADF). Genotype x environment interactions, specifically breed x year-season farrowed and breed X parity (for ADG), were found to be highly significant. Certain results, however, were reasonably consistent across environments. Duroc-sired pigs grew more efficiently than other sire breed groups (3.11 vs 3.21 F/G), although there were no significant differences in ADF between sire groups. Duroc-sired pigs had less BF than other three-breed cross pigs, based upon within breed of dam comparisons, suggesting differences in composition between the more efficient Duroc-sired pigs and other breed groups. Landrace-sired pigs were fatter than other sire groups. No real differences between crossbred-sired pigs and the average of contemporary purebred- sired pigs were apparent for F/G, ADF, ADG, AGE or BF. Assuming paternal heterosis to be zero, these results suggested recombination effects to be negligible for postweaning performance traits. Apart from via direct genetic effects, mating crossbred rather than purebred boars to females of different breeding should have little or no impact on feedlot performance of offspring produced.

Data on 213 purebred and 524 crossbred gilts produced in a four-breed diallel crossing design involving the Duroc (D), Yorkshire (Y), Landrace (L) and Spotted (S)breeds were analyzed for age and weight at puberty. The breed of sire x breed of dam interaction was significant for both age and weight at puberty. However, differences among reciprocals were not significant, and thus, reciprocal means were combined. Crossbreds were younger (7.9 d) and heavier (1.2 kg) at puberty than purebreds. Significant heterosis for age at puberty was found for D X L (-14.3 d),S x D (-12.8 d) and S x L (-9.0 d) crosses. No significant heterosis was found in L x Y, S x Y and D x L crosses. The only crossbred group that exhibited significant heterosis for weight at puberty was the L x Y (4.5 kg). The oldest breed groups at puberty were the D and Y, while the youngest were all possible two-breed crosses involving D, S and L. Few differences were observed among breed groups in weight at puberty, however, the D x Y was significantly heavier than the L, Y, S x L and D x L.

In het Europese project ‘COBRA’ onderzoekt Inagro samen met andere Europese partners in hoeverre nieuwe veredelingsconcepten de weerbaarheid van granen tegen verschillende stressfactoren (vorst, ziekte, droogte,…) kunnen verbeteren. Samengestelde kruisingspopulaties ontstaan uit een kruising van verschillende rassen waarbij de zaadoogst van de gehele populatie wordt gebruikt om een volgende generatie te creëren. Op die manier ontstaan populaties met een extreem hoge genetische diversiteit. In een verkennende proef op het biologisch proefbedrijf van Inagro bleken deze populaties onder hoge druk van gele roest alvast niet onder te doen voor enkele referentierassen wintertarwe uit Noord-Frankrijk.