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See detailFirst results in the use of milk mid-infrared spectra in the detection of lameness in Austrian dairy cows
Mineur, Axelle ULiege; Köck, Astrid; Grelet, Clément ULiege et al

in Agriculturae Conspectus Scientificus (in press)

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See detailBayesian single-step genomic evaluations combining local and foreign information in Walloon Holsteins
Colinet, Frédéric ULiege; Vandenplas, J.; Vanderick, Sylvie ULiege et al

in Animal (2017)

Most dairy cattle populations found in different countries around the world are small to medium sized and use many artificial insemination bulls imported from different foreign countries. The Walloon ... [more ▼]

Most dairy cattle populations found in different countries around the world are small to medium sized and use many artificial insemination bulls imported from different foreign countries. The Walloon population in the southern part of Belgium is a good example for such a small-scale population. Wallonia has also a very active community of Holstein breeders requesting high level genetic evaluation services. Single-step Genomic BLUP (ssGBLUP) methods allow the simultaneous use of genomic, pedigree and phenotypic information and could reduce potential biases in the estimation of genomically enhanced breeding values (GEBV). Therefore, in the context of implementing a Walloon genomic evaluation system for Holsteins, it was considered as the best option. However, in contrast to multi-step genomic predictions, natively ssGBLUP will only use local phenotypic information and is unable to use directly important other sources of information coming from abroad, for example Multiple Across Country Evaluation (MACE) results as provided by the Interbull Center (Uppsala, Sweden). Therefore, we developed and implemented single-step Genomic Bayesian Prediction (ssGBayes), as an alternative method for the Walloon genomic evaluations. The ssGBayes method approximated the correct system of equations directly using estimated breeding values (EBV) and associated reliabilities (REL) without any explicit deregression step. In the Walloon genomic evaluation, local information refers to Walloon EBV and REL and foreign information refers to MACE EBV and associated REL. Combining simultaneously all available genotypes, pedigree, local and foreign information in an evaluation can be achieved but adding contributions to left-hand and right-hand sides subtracting double-counted contributions. Correct propagation of external information avoiding double counting of contributions due to relationships and due to records can be achieved. This ssGBayes method computed more accurate predictions for all types of animals. For example, for genotyped animals with low Walloon REL (<0.25) without MACE results but sired by genotyped bulls with MACE results, the average increase of REL for the studied traits was 0.38 points of which 0.08 points could be traced to the inclusion of MACE information. For other categories of genotyped animals, the contribution by MACE information was also high. The Walloon genomic evaluation system passed for the first time the Interbull GEBV tests for several traits in July 2013. Recent experiences reported here refer to its use in April 2016 for the routine genomic evaluations of milk production, udder health and type traits. Results showed that the proposed methodology should also be of interest for other, similar, populations. [less ▲]

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See detailGrowth and carcass performances of guinea fowls reared under intensive system in Benin
Houndonougbo, Pascal ULiege; REIS MOTA, Rodrigo ULiege; Chrysostome, A.A.M. Christophe et al

in Livestock of Research for Rural Development (LRRD) (2017), 29(10),

Several local guinea fowl varieties continued to be reared in extensive systems in Benin, even though productivity remains low. Improving rearing conditions through feeding and housing may enhance local ... [more ▼]

Several local guinea fowl varieties continued to be reared in extensive systems in Benin, even though productivity remains low. Improving rearing conditions through feeding and housing may enhance local guinea fowls productivity in Benin. Therefore, the objective of this study was to verify growth and carcass performances of five (Common, Bonaparte, Grey, White and Black) local guinea fowl varieties under intensive management conditions. At birth, 36 keets (young guinea fowls) of each identified variety were randomly divided into six batches and reared up to 16 weeks old under the same feeding and housing conditions. Body weights were recorded up to week 15. At week 16, carcass measurements were also taken. Growth performances and carcass measurements (morphological and visceral) differed among guinea fowl varieties. The heaviest body weight was observed in Common (832±24g) and the lowest in Black variety (698±39g). Highest carcass yield was observed in Grey variety. Liver weight, intestine length and caecum length were highest in Bonaparte variety. Gizzard weight and thigh proportion were highest in Common variety. Breast weight and breast proportion were highest in Grey guinea fowls. Body weight was moderately correlated with drumstick length, body length, wing size, tarsus diameter, thigh length and thorax circumference (range r = 0.34-0.60). The phenotypic variability and its impact on the characterization of these varieties implies that they are genetically different strains, supporting the hypothesis that the guinea fowl population in Benin presents opportunities for genetic improvement. [less ▲]

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See detailCharacteristic of Guinea Fowl breeding in West Africa: Review
Houndonougbo, Pascal ULiege; Bindelle, Jérôme ULiege; Chrysostome, A.A.M. Christophe et al

in Tropicultura (2017), 35(3), 222-230

Guinea fowl production in sub-Saharan Africa (SSA) is generally practiced under family and traditional rearing systems mainly for consumption and income generation, but this species plays also a major ... [more ▼]

Guinea fowl production in sub-Saharan Africa (SSA) is generally practiced under family and traditional rearing systems mainly for consumption and income generation, but this species plays also a major socio-cultural role in specific ceremonies. Birds are kept in free range or in confinement with outdoor access and fed on grain cereals, vegetables, edible termites and kitchen residues found in nature or occasionally supplied by the farmers. Several Guinea fowl varieties are observed and all are characterized by slow growth, high mortality of young and a relatively wild instinct. Although this avian species is less sensitive to some poultry diseases (Newcastle disease, Marek disease, Gumboro disease, etc), local guinea fowl are very sensitive to other poorly controlled diseases that require further study. These varieties differ greatly by their feather color, their morphological characteristics and growth performance, but further thorough and sustained research is needed to quantify these differences. Several researches established the nutritional requirements of local Guinea fowl but in terms of breeding, little works were done compared to chicken. Some recessive and dominant genes as well as genotypic differences were highlighted between varieties. [less ▲]

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See detailGenetic evaluation for birth and conformation traits in dual-purpose Belgian Blue cattle using a mixed inheritance model
REIS MOTA, Rodrigo ULiege; Mayeres, P.; Bastin, Catherine et al

in Journal of Animal Science (2017)

The segregation of the causal mutation (mh) in the muscular hypertrophy gene in dual-purpose Belgian Blue (dpBB) cattle is considered to result in greater calving difficulty (dystocia). Establishing ... [more ▼]

The segregation of the causal mutation (mh) in the muscular hypertrophy gene in dual-purpose Belgian Blue (dpBB) cattle is considered to result in greater calving difficulty (dystocia). Establishing adapted genetic evaluations might overcome this situation through efficient selection. However, the heterogeneity of dpBB populations at the mh locus implies separating the major gene and other polygenic effects in complex modeling. The use of mixed inheritance models may be an interesting option because they simultaneously assume both influences. A genetic evaluation in dpBB based on a mixed inheritance model was developed for birth and conformation traits: gestation length (GL), calving difficulty (CD), birth weight (BiW), and body conformation score (BC). A total of 27,362 animals having records were used for analyses. The total number of animals in the pedigree used to build the numerator relationship matrix was 62,617. Genotypes at the mh locus were available for 2,671 animals. Missing records at this locus were replaced with genotype probabilities. A total of 13,221 (48.3%) were registered as dpBB, 1,287 (4.7%) as beef Belgian Blue, and 12,854 (47.0%) were unknown. From those 13,221dpBB animals, 650, 849, and 534 had double or single copies or no copy, respectively, of the causal mutation (mh) in the muscular hypertrophy gene, whereas 11,188 had missing genotypes. This heterogeneity at the mh locus may be the reason for high variability in the studied traits, that is, high heritability estimates of 0.33, 0.30, 0.38, and 0.43 for GL, CD, BiW, and BC, respectively. In general, additive (P < 0.05) and dominance (P < 0.001) allele substitution for calves and dams had significant impact for all traits. The moderate coefficient of genetic variation (27.80%) and high direct heritability (0.28) for CD suggested genetic variability in dpBB and possible genetic improvement through selection. This variability has allowed dpBB breeders to successfully apply mass selection in the past. Genetic trend means from 1988 to 2016 showed that sire selection for CD within genotype was progressively applied by breeders. The selection intensity was more important for CD in double-muscled lines than in segregated lines. Our study illustrated the possible confusion caused by the use of major genes in selection and the importance of fitting appropriate models such as mixed inheritance models that combine polygenic and gene content information. [less ▲]

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See detailPhenotypic, socio-economic and growth features of Guinea fowls raised under different village systems in West Africa
Houndonougbo, Pascal ULiege; Chrysostome, A. A. M. Christophe; REIS MOTA, Rodrigo ULiege et al

in African Journal of Agricultural Research (AJAR) (2017), 12(26), 2232-2241

In Benin, family poultry farming has become an important activity in economic and social aspects that contribute to food security, poverty reduction and well-being. However, current information about ... [more ▼]

In Benin, family poultry farming has become an important activity in economic and social aspects that contribute to food security, poverty reduction and well-being. However, current information about poultry production and consumption is still limited. This information would be useful to improve the sustainable exploitation of agricultural and commercial genetic resources. We aimed to identify and assess the socio-economic and phenotypic features as well as to investigate phenotypic variability and growth performance of guinea fowls raised under different environments. Growth performance and survival rates of local guinea fowl varieties were recorded in three zones of Benin: Collines, Atacora and Borgou. Seven varieties, Gray, Common, Bonaparte, White, Black, Isabelle and Multicolored, were identified in Benin. The farmers choose a variety to be raised based on breeding system, agro-ecological zone, disease resistance, market price and production purpose. Bonaparte, Common and Gray varieties emerged as the most resistant whereas White, Black and Gray outperformed in growth and may be used for breeding purposes. The semi-confinement system could be recommended for startup as a temporary solution to improve production of local guinea fowls in Benin. The existence of several varieties on farms does not encourage genetic conservation and improvement of these resources. Establishing selection or crossbreeding programs in controlled environments would be more appropriate for guinea fowls raised in Benin. [less ▲]

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See detailGenetic parameters of mid-infrared methane predictions and their relationships with milk production traits in Holstein cattle
Kandel, Purna; Vanrobays, Marie-Laure; Vanlierde, Amélie et al

in Journal of Dairy Science (2017), 100(7), 5578-5591

Many countries have pledged to reduce greenhouse gases. In this context, the dairy sector is one of the identified sectors to adapt production circumstances to address socio-environmental constraints due ... [more ▼]

Many countries have pledged to reduce greenhouse gases. In this context, the dairy sector is one of the identified sectors to adapt production circumstances to address socio-environmental constraints due to its large carbon footprint related to CH4 emission. This study aimed mainly to estimate (1) the genetic parameters of 2 milk mid-infrared-based CH4 proxies [predicted daily CH4 emission (PME, g/d), and log-transformed predicted CH4 intensity (LMI)] and (2) their genetic correlations with milk production traits [milk (MY), fat (FY), and protein (PY) yields] from first- and second-parity Holstein cows. A total of 336,126 and 231,400 mid-infrared CH4 phenotypes were collected from 56,957 and 34,992 first- and second-parity cows, respectively. The PME increased from the first to the second lactation (433 vs. 453 g/d) and the LMI decreased (2.93 vs. 2.86). We used 20 bivariate random regression test-day models to estimate the variance components. Moderate heritability values were observed for both CH4 traits, and those values decreased slightly from the first to the second lactation (0.25 ± 0.01 and 0.22 ± 0.01 for PME; 0.18 ± 0.01 and 0.17 ± 0.02 for LMI). Lactation phenotypic and genetic correlations were negative between PME and MY in both first and second lactations (−0.07 vs. −0.07 and −0.19 vs. −0.24, respectively). More close scrutiny revealed that relative increase of PME was lower with high MY levels even reverting to decrease, and therefore explaining the negative correlations, indicating that higher producing cows could be a mitigation option for CH4 emission. The PME phenotypic correlations were almost equal to 0 with FY and PY for both lactations. However, the genetic correlations between PME and FY were slightly positive (0.11 and 0.12), whereas with PY the correlations were slightly negative (−0.05 and −0.04). Both phenotypic and genetic correlations between LMI and MY or PY or FY were always relatively highly negative (from −0.21 to −0.88). As the genetic correlations between PME and LMI were strong (0.71 and 0.72 in first and second lactation), the selection of one trait would also strongly influence the other trait. However, in animal breeding context, PME, as a direct quantity CH4 proxy, would be preferred to LMI, which is a ratio trait of PME with a trait already in the index. The range of PME sire estimated breeding values were 22.1 and 29.41 kg per lactation in first and second parity, respectively. Further studies must be conducted to evaluate the effect of the introduction of PME in a selection index on the other traits already included in this index, such as, for instance, fertility or longevity. [less ▲]

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See detailCow milk coagulation: process description, variation factors and evaluation methodologies. A review.
Troch, Thibault; Lefebure, Emilie ULiege; Baeten, Vincent et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2017), 21

Introduction. For dairy producers who want to transform their milk, the ability of milk to coagulate is an important parameter. It makes it possible to transform milk into cheese. Therefore, it is ... [more ▼]

Introduction. For dairy producers who want to transform their milk, the ability of milk to coagulate is an important parameter. It makes it possible to transform milk into cheese. Therefore, it is necessary to understand the coagulation process and the techniques to measure it in order to achieve the best transformation performance. The objective of this review is to describe the milk coagulation process, the factors influencing it and the methods for measuring the coagulation of milk at lab level. Literature. The processing of milk into cheese involves three steps: coagulation, dewatering and refining. Coagulation is a key step which involves the use of rennet and depends on several parameters (pH, calcium content, temperature, etc.). Some milks never coagulate. To measure the coagulation ability of milk and identify different parameters in milk coagulation properties, the Formagraph, the computerized renneting meter and the Optigraph have been developed (reference methods). Equations have been developed using infrared spectrometry to predict the parameters obtained by the reference methods. Conclusions. The milk coagulation mechanism is known. However, the issue of non-coagulating milk persists and represents a real challenge in terms of yield. The use of infrared is a faster alternative to reference methods that measure the coagulation properties of milk, but still requires an improvement in prediction equations. [less ▲]

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See detailUsefulness of multi-breed models in genetic evaluation of direct and maternal calving ease in Holstein and Belgian Blue Walloon purebreds and crossbreds
Vanderick, Sylvie ULiege; Gillon, Alain; Glorieux, Géry et al

in Livestock Science (2017), 198

The objective of this study was to verify the feasibility of a joint genetic evaluation system for calving ease trait of Belgian Blue (BBB) and Holstein (HOL) Walloon cattle based on data of purebred and ... [more ▼]

The objective of this study was to verify the feasibility of a joint genetic evaluation system for calving ease trait of Belgian Blue (BBB) and Holstein (HOL) Walloon cattle based on data of purebred and crossbred animals. Variance components and derived genetic parameters for purebred BBB and HOL animals were estimated by using single-breed linear animal models. This analysis showed clear genetic differences between breeds. Estimates of direct and maternal heritabilities (± standard error) were 0.34 (±0.02) and 0.09 (±0.01) for BBB, respectively, but only 0.09 (±0.01) and 0.04 (±0.01) for HOL, respectively. Moreover, a significant negative genetic correlation between direct and maternal effects was obtained in both breeds: −0.46 (±0.04) for BBB and −0.29 (±0.11) for HOL. Variance components and derived genetic parameters for purebred BBB and HOL and crossbred BBB ×× HOL cattle were then estimated by using two multi-breed linear animal models: a multi-breed model based on a random regression test-day model (Model MBV), and a multi-breed model based on the random regression multi-breed model (Model MBSM). Both multi-breed models use different functions of breed proportions as random regressions, thereby enabling modelling different additive effects according to animal's breed composition. The main difference between these models is the way in which relationships between breeds are accounted for in the genetic (co)variance structure. Genetic parameters differed between single-breed and multi-breed analysis, but are similar to the literature. For BBB, estimates of direct and maternal heritabilities (±SE) were 0.45 (±0.07) and 0.08 (±0.01) by using Model MBV, and 0.45 (±0.08) and 0.09 (±0.02) for Model MBSM, respectively. For HOL, these estimates were 0.18 (±0.04) and 0.05 (±0.01) using Model MBV, and 0.16 (±0.04) and 0.05 (±0.01) for Model MBSM, respectively. Reliability gains (up to 25%) indicated that the use of crossbred data in the multi-breed models had a positive influence on the estimation of genetic merit of purebred animals. A slight re-ranking of purebred sires and maternal grandsires was observed between single-breed and multi-breed models. Moreover, both multi-breed models can be considered as quasi-equivalent models because they performed almost equally well with respect to MSE and correlations, for purebred and crossbred animals. [less ▲]

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See detailNational single-step genomic method that integrates multi-national genomic information
Vandenplas, J.; Spehar, M.; Potocnik, K. et al

in Journal of Dairy Science (2017), 100(1), 465-478

Abstract The aim of this paper was to develop a national single-step genomic BLUP that integrates multi-national genomic estimated breeding values (EBV) and associated reliabilities without double ... [more ▼]

Abstract The aim of this paper was to develop a national single-step genomic BLUP that integrates multi-national genomic estimated breeding values (EBV) and associated reliabilities without double counting dependent data contributions from the different evaluations. Simultaneous use of all data, including phenotypes, pedigree, and genotypes, is a condition to obtain unbiased EBV. However, this condition is not always fully met, mainly due to unavailability of foreign raw data for imported animals. In dairy cattle genetic evaluations, this issue is traditionally tackled through the multiple across-country evaluation (MACE) of sires, performed by Interbull Centre (Uppsala, Sweden). Multiple across-country evaluation regresses all the available national information onto a joint pedigree to obtain country-specific rankings of all sires without sharing the raw data. In the context of genomic selection, the issue is handled by exchanging sire genotypes and by using MACE information (i.e., MACE EBV and reliabilities), as a valuable source of “phenotypic” data. Although all the available data are considered, these “multi-national” genomic evaluations use multi-step methods assuming independence of various sources of information, which is not met in all situations. We developed a method that handles this by single-step genomic evaluation that jointly (1) uses national phenotypic, genomic, and pedigree data; (2) uses multi-national genomic information; and (3) avoids double counting dependent data contributions from an animal’s own records and relatives’ records. The method was demonstrated by integrating multi-national genomic EBV and reliabilities of Brown Swiss sires, included in the InterGenomics consortium at Interbull Centre, into the national evaluation in Slovenia. The results showed that the method could (1) increase reliability of a national (genomic) evaluation; (2) provide consistent ranking of all animals: bulls, cows, and young animals; and (3) increase the size of a genomic training population. These features provide more efficient and transparent selection throughout a breeding program. [less ▲]

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See detailGenomics of a revived breed: Case study of the Belgian campine cattle.
Francois, Liesbeth; Wijnrocx, Katrien; Colinet, Frédéric ULiege et al

in PLoS ONE (2017), 12(4), 0175916

Through centuries of both natural and artificial selection, a variety of local cattle populations arose with highly specific phenotypes. However, the intensification and expansion of scale in animal ... [more ▼]

Through centuries of both natural and artificial selection, a variety of local cattle populations arose with highly specific phenotypes. However, the intensification and expansion of scale in animal production systems led to the predominance of a few highly productive cattle breeds. The loss of local populations is often considered irreversible and with them specific qualities and rare variants could be lost as well. Over these last years, the interest in these local breeds has increased again leading to increasing efforts to conserve these breeds or even revive lost populations, e.g. through the use of crosses with similar breeds. However, the remaining populations are expected to contain crossbred individuals resulting from introgressions. They are likely to carry exogenous genes that affect the breed's authenticity on a genomic level. Using the revived Campine breed as a case study, 289 individuals registered as purebreds were genotyped on the Illumina BovineSNP50. In addition, genomic information on the Illumina BovineHD and Illumina BovineSNP50 of ten breeds was available to assess the current population structure, genetic diversity, and introgression with phenotypically similar and/or historically related breeds. Introgression with Holstein and beef cattle genotypes was limited to only a few farms. While the current population shows a substantial amount of within-breed variation, the majority of genotypes can be separated from other breeds in the study, supporting the re-establishment of the Campine breed. The majority of the population is genetically close to the Deep Red (NL), Improved Red (NL) and Eastern Belgium Red and White (BE) cattle, breeds known for their historical ties to the Campine breed. This would support an open herdbook policy, thereby increasing the population size and consequently providing a more secure future for the breed. [less ▲]

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See detailAssessing the effect of pregnancy stage on milk composition of dairy cows using mid-infrared spectra
Laine, Aurélie ULiege; Bastin, C.; Grelet, C. et al

in Journal of Dairy Science (2017), 100(4), 2863-2876

ABSTRACT Changes in milk production traits (i.e., milk yield, fat, and protein contents) with the pregnancy stage are well documented. To our knowledge, the effect of pregnancy on the detailed milk ... [more ▼]

ABSTRACT Changes in milk production traits (i.e., milk yield, fat, and protein contents) with the pregnancy stage are well documented. To our knowledge, the effect of pregnancy on the detailed milk composition has not been studied so far. The mid-infrared (MIR) spectrum reflects the detailed composition of a milk sample and is obtained by a nonexhaustive and widely used method for milk analysis. Therefore, this study aimed to investigate the effect of pregnancy on milk MIR spectrum in addition to milk production traits (milk yield, fat, and protein contents). A model including regression on the number of days pregnant was applied on milk production traits (milk yield, fat, and protein contents) and on 212 spectral points from the MIR spectra of 9,757 primiparous Holstein cows from Walloon herds. Effects of pregnancy stage were expressed on a relative scale (effect divided by the squared root of the phenotypic variance); this allowed comparisons between effects on milk traits and on 212 spectral points. Effect of pregnancy stage on production traits were in line with previous studies indicating that the model accounted well for the pregnancy effect. Trends of the relative effect of the pregnancy stage on the 212 spectral points were consistent with known and observed effect on milk traits. The highest effect of the pregnancy was observed in the MIR spectral region from 968 to 1,577 cm−1. For some specific wavenumbers, the effect was higher than for fat and protein contents in the beginning of the pregnancy (from 30 to 90 or 120 d pregnant). In conclusion, the effect of early pregnancy can be observed in the detailed milk composition through the analysis of the MIR spectrum of bovine milk. Further analyses are warranted to explore deeply the use of MIR spectra of bovine milk for breeding and management of dairy cow pregnancy. [less ▲]

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See detailDrawbacks and benefits of hygienic behavior in honey bees (Apis mellifera L.): a review
Leclercq, Gil; Pannebakker, Bart; Gengler, Nicolas ULiege et al

in Journal of Apicultural Research (2017), 56(4), 366-375

The hygienic behavior of honey bee workers contributes to the social immunity of colonies. The ability of workers to detect and remove unhealthy or dead brood prevents the transmission of brood diseases ... [more ▼]

The hygienic behavior of honey bee workers contributes to the social immunity of colonies. The ability of workers to detect and remove unhealthy or dead brood prevents the transmission of brood diseases inside the colony. Over the last five decades, this trait has been extensively studied and improved in several research and breeding programs. Given the strong interest for hygienic behavior, we here review the costs and benefits associated with this trait, extending preceding reviews on this subject from the late 1990s. Since the 1990s, there have been no major new insights on the efficiency of this behavior against American foulbrood and chalkbrood. However, the number of publications on hygienic behavior against the mite Varroa destructor has considerably increased, fueling the debate regarding the efficiency of hygienic behavior against this parasite. Breeding programs have shown that selection for a specific trait might also impact other traits. Thus, we also review the cost of trade-offs between hygienic behavior and other economically important traits for bee breeders. Overall, the benefits of hygienic behavior seem to largely outweigh its costs for both colonies and bee breeders. [less ▲]

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See detailStandardization of milk mid-infrared spectrometers for the transfer and use of multiple models
Grelet, C.; Pierna, J. A. Fernández; Dardenne, P. et al

in Journal of Dairy Science (2017), 100(10), 7910-7921

An increasing number of models are being developed to provide information from milk Fourier transform mid-infrared (FT-MIR) spectra on fine milk composition, technological properties of milk, or even cows ... [more ▼]

An increasing number of models are being developed to provide information from milk Fourier transform mid-infrared (FT-MIR) spectra on fine milk composition, technological properties of milk, or even cows' physiological status. In this context, and to take advantage of these existing models, the purpose of this work was to evaluate whether a spectral standardization method can enable the use of multiple equations within a network of different FT-MIR spectrometers. The piecewise direct standardization method was used, matching “slave” instruments to a common reference, the “master.” The effect of standardization on network reproducibility was assessed on 66 instruments from 3 different brands by comparing the spectral variability of the slaves and the master with and without standardization. With standardization, the global Mahalanobis distance from the slave spectra to the master spectra was reduced on average from 2,655.9 to 14.3, representing a significant reduction of noninformative spectral variability. The transfer of models from instrument to instrument was tested using 3 FT-MIR models predicting (1) the quantity of daily methane emitted by dairy cows, (2) the concentration of polyunsaturated fatty acids in milk, and (3) the fresh cheese yield. The differences, in terms of root mean squared error, between master predictions and slave predictions were reduced after standardization on average from 103 to 17 g/d, from 0.0315 to 0.0045 g/100 mL of milk, and from 2.55 to 0.49 g of curd/100 g of milk, respectively. For all the models, standard deviations of predictions among all the instruments were also reduced by 5.11 times for methane, 5.01 times for polyunsaturated fatty acids, and 7.05 times for fresh cheese yield, showing an improvement of prediction reproducibility within the network. Regarding the results obtained, spectral standardization allows the transfer and use of multiple models on all instruments as well as the improvement of spectral and prediction reproducibility within the network. The method makes the models universal, thereby offering opportunities for data exchange and the creation and use of common robust models at an international level to provide more information to the dairy sector from direct analysis of milk. [less ▲]

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See detailThe Impact of Diseases Transmission in Pollinators Decline
Noël, Grégoire ULiege; Bebermans, Julien ULiege; Colinet, Frédéric ULiege et al

Scientific conference (2016, December 02)

Ongoing global biodiversity loss is a growing concern for our society. This involves also the pollinators community which ensures insect-pollinated plant reproduction in our natural environment and ... [more ▼]

Ongoing global biodiversity loss is a growing concern for our society. This involves also the pollinators community which ensures insect-pollinated plant reproduction in our natural environment and provides a great ecosystem service to mankind, particularly for food safety and human welfare. The aim of this study is two-fold: i) to produce a comprehensive update of the decline of pollinators at global scale and ii) to focus especially on the issue of pollinators disease transmission. In this research we argue that the cause of insect-pollinator decline is multi-factorial, including anthropogenic pressures such as land-use change (habitats loss, agricultural intensification…), climate change, pesticides and the spread of alien species and diseases. It also appears that the high prevalence of a broad range of insects and commercial use of pollinators are key drivers of pathogens transmission (virus, parasites …). However, the dynamics of pathogens transmission is still poorly known and, in turn, more scientific research must be performed to have a better insight of this issue. Finally, pollinators decline results from synergetic actions among these stress generators at different spatio-temporal levels emphasized by the globalization of commercial exchanges. [less ▲]

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See detailStudy of the impact of the pregnancy stage on milk composition of primiparous Holstein dairy cows using the mid-infrared spectra of milk
Laine, Aurélie ULiege; Bastin, Catherine; Grelet, Clément ULiege et al

in Journal of Dairy Science (2016), 100

Changes in milk production traits (i.e., milk yield, fat, and protein contents) with the pregnancy stage are well documented. To our knowledge, the effect of pregnancy on the detailed milk composition has ... [more ▼]

Changes in milk production traits (i.e., milk yield, fat, and protein contents) with the pregnancy stage are well documented. To our knowledge, the effect of pregnancy on the detailed milk composition has not been studied so far. The mid-infrared (MIR) spectrum reflects the detailed composition of a milk sample and is obtained by a nonexhaustive and widely used method for milk analysis. Therefore, this study aimed to investigate the effect of pregnancy on milk MIR spectrum in addition to milk production traits (milk yield, fat, and protein contents). A model including regression on the number of days pregnant was applied on milk production traits (milk yield, fat, and protein contents) and on 212 spectral points from the MIR spectra of 9,757 primiparous Holstein cows from Walloon herds. Effects of pregnancy stage were expressed on a relative scale (effect divided by the squared root of the phenotypic variance); this allowed comparisons between effects on milk traits and on 212 spectral points. Effect of pregnancy stage on production traits were in line with previous studies indicating that the model accounted well for the pregnancy effect. Trends of the relative effect of the pregnancy stage on the 212 spectral points were consistent with known and observed effect on milk traits. The highest effect of the pregnancy was observed in the MIR spectral region from 968 to 1,577 cm−1. For some specific wavenumbers, the effect was higher than for fat and protein contents in the beginning of the pregnancy (from 30 to 90 or 120 d pregnant). In conclusion, the effect of early pregnancy can be observed in the detailed milk composition through the analysis of the MIR spectrum of bovine milk. Further analyses are warranted to explore deeply the use of MIR spectra of bovine milk for breeding and management of dairy cow pregnancy. [less ▲]

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See detailA simple method to predict methane emissions based on milk mid infrared spectra
Vanlierde, Amélie ULiege; Dehareng, Frédéric; Froidmont, Eric et al

Poster (2016, October)

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See detailNovel innovative possibilities for the dairy industry opened by common format of FT-MIR instruments
Grelet, Clément ULiege; Fernandez Pierna, Juan Antonio; Dardenne, Pierre et al

Poster (2016, October)

FT-MIR technology is worldwide used for fast and cost effective determination of major milk components. However, due to the different individual response of each instrument the potential of this ... [more ▼]

FT-MIR technology is worldwide used for fast and cost effective determination of major milk components. However, due to the different individual response of each instrument the potential of this technology is currently underexploited as new tools cannot be easily ported to other instruments. Recently a standardization method was developed in order to harmonize the spectral response format between instruments of different brands and models but also across time for each spectrometer. The method matches monthly the infrared response of all spectrometers on the response of a reference instrument, making all machines talking a common language. The objective is to allow the creation and the use of common, new and innovative concepts by pooling resources and sharing data. Using this method, new tools for analysis of milk quality and milk technological properties have been created and shared within the network, as fatty acids and minerals predictions or milk coagulation properties. New concepts requiring a common spectral format have been developed like the untargeted detection of milk contaminant and abnormal milk or the determination of milk geographic origin. Models in relation with the status of the dairy cow were also created and shared as to predict ketosis, negative energy balance or methane emissions. Therefore models can be developed at one place and deployed within the entire network, in which 90 instruments are currently monthly standardized. [less ▲]

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See detailEffect of curve traits and Age at first calving on productive life of Holstein primiparous Walloon cows
Grayaa, Marwa; Hammami, Hedi ULiege; Hanzen, Christian ULiege et al

Poster (2016, September 02)

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See detailPotential of milk MIR spectra to develop new health phenotypes for dairy cows in the GplusE project
Vanlierde, A.; Grelet, C.; Gengler, Nicolas ULiege et al

in Book of abstracts of the 67 rd Annual Meeting of the European Association for Animal Production (2016)

The current context leads to more and more efficient and rational animal productions. The objective of the “Genotype plus Environment” project (G plus E) is to support novel phenotyping approaches to ... [more ▼]

The current context leads to more and more efficient and rational animal productions. The objective of the “Genotype plus Environment” project (G plus E) is to support novel phenotyping approaches to provide large scale phenotypes for a genomic study and contributing to the sustainability of dairy cow production systems. In this framework, 3 European farms (AFBI-UK, UCD-IRL, AU-DK) collected observations (weight, body condition score, uterine health, residual feed intake, lameness,…) and samples (milk, blood, liver, feed,…) on 135 dairy cows, from calving until day 49. Those data constitute a substantial database which permits to link those phenotypes of interest to potential biomarkers, and especially the mid infrared (MIR) spectra of milk. Predicting phenotypes of interest from milk MIR spectra could be very interesting to detect specific status of cows in a cost effective, rapid and routine process, allowing the acquisition of data at large scale. Classification models have been developed from milk MIR spectra. For example a model built on 60 observations permits to distinguish animals with or without lameness with a good predicted classification of 68 and 71% respectively. Otherwise Regression models have been performed to predict molecules of interest from milk MIR spectra. Some of them can be used with a threshold (eg. level of milk NAGase which is associated to an inflammation status) some others present potential to be predicted quantitatively (eg. IGF1 which is linked to uterine health). This database therefore allows developing tools to predict new health indicators from milk MIR spectra that can be easily implemented at large scale. Those observations will be validated through new data collected with the same protocol from 3 other European farms. [less ▲]

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