The Experts below are selected from a list of 2007 Experts worldwide ranked by ideXlab platform

Marijke Aluwé - One of the best experts on this subject based on the ideXlab platform.

  • On-farm prevalence of and potential risk factors for Boar Taint.
    Animal : an international journal of animal bioscience, 2021
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract Boar Taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence Boar Taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between Boar Taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory Boar Taint prevalence was 1.8 ± 0.8%. Boar Taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less Boar Taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower Boar Taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, Boar Taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower Boar Taint prevalences. This may to some extent be explained by the negative association between Boar Taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower Boar Taint levels.

  • Developing and Understanding Olfactory Evaluation of Boar Taint.
    Animals : an open access journal from MDPI, 2020
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Trained expert panels are used routinely in Boar Taint research, with varying protocols for training of panelists and scoring methods. We describe a standardized process for training and scoring, to contribute to standardize the olfactory detection of Boar Taint. Three experiments are described in which we (1) evaluate the importance of training and the effect of the previous sample, (2) determine detection thresholds on strips and in fat for our panel, and (3) test priming panelists before Boar Taint evaluation. For the final evaluation of Boar Taint, we propose a consistent three-person evaluation scoring on a 0–4 scale using a final mean score of 0.5 as the cut-off for Boar Taint. This gave an optimal sensitivity of 0.81 and a specificity of 0.56 compared to chemical cut-offs. Even limited training proved useful, but priming assessors with strips did not improve the evaluation of fat samples. Detection thresholds were higher in fat compared to strips, except for indole. We recommend panelists to always smell a non-Tainted control sample after a Tainted one as a ‘reset’ mechanism, before continuing. For longitudinal studies, we additionally advise to set up an expert panel with a fixed number of assessors performing each evaluation in duplicate.

  • on farm intervention studies on reduction of Boar Taint prevalence feeding strategies presence of gilts and time in lairage
    Research in Veterinary Science, 2018
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract One of the challenges in the production of entire male pigs is the occurrence of Boar Taint. We separately tested the effect of 3 management strategies to reduce Boar Taint on respectively 2, 3, and 6 Flemish pig farms: 1) adapted feeding strategies, 2) presence of gilts in the compartment, and 3) varying lairage duration at the slaughterhouse. A commercialized feed concept resulted in a significant reduction of olfactory Boar Taint prevalence when fed for 2 weeks (T2W) compared to control (T-CON) (P = 0.030). For T2W and when fed for 3 weeks (T3W), androstenone (AND) (P = 0.002 for T2W, P = 0.029 for T3W) and skatole (SKA) (P  3 h did not significantly affect Boar Taint.

  • olfactory evaluation of Boar Taint effect of factors measured at slaughter and link with Boar Taint compounds
    Animal, 2017
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of Boar Taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in Boar Taint prevalence, (2) investigate factors measured at slaughter influencing Boar Taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of Boar Taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory Boar Taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for Boar Taint. Average Boar Taint prevalence (score 3) was 5.6 +/- 2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3 +/- 3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having Boar Taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of Boar Taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for Boar Taint than AND. There were no significant synergetic effects between Boar Taint compounds.

  • Boar Taint compound levels in back fat versus meat products: Do they correlate?
    Food chemistry, 2016
    Co-Authors: Jella Wauters, Marijke Aluwé, Vicky Vercruysse, Kaat Verplanken, Lynn Vanhaecke
    Abstract:

    Surgical castration of male pigs will soon be abandoned, turning a major advantage of this practice, the elimination of Boar Taint, into the biggest challenge for pig industry when raising intact male pigs becomes common practice. To map the (economical) consequences in relation to Boar-Taint consumer acceptance, as well as offer a processing strategy for Tainted carcasses to stockholders, the current study investigated not only back fat Boar Taint levels, but additionally generated information on the levels of Boar Taint compounds recovered after the production of commercially relevant meat products using UHPLC-HRMS laboratory analysis. Our results demonstrate that levels of androstenone, skatole and indole in back fat and meat products tend to correlate strongly, particularly in fatty meat products (generally r>0.80). Concentration values in the edible (lean) meat fraction were significantly lower compared to back fat and fat sampled from fresh or processed meat (p

Lynn Vanhaecke - One of the best experts on this subject based on the ideXlab platform.

  • On-farm prevalence of and potential risk factors for Boar Taint.
    Animal : an international journal of animal bioscience, 2021
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract Boar Taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence Boar Taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between Boar Taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory Boar Taint prevalence was 1.8 ± 0.8%. Boar Taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less Boar Taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower Boar Taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, Boar Taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower Boar Taint prevalences. This may to some extent be explained by the negative association between Boar Taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower Boar Taint levels.

  • Developing and Understanding Olfactory Evaluation of Boar Taint.
    Animals : an open access journal from MDPI, 2020
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Trained expert panels are used routinely in Boar Taint research, with varying protocols for training of panelists and scoring methods. We describe a standardized process for training and scoring, to contribute to standardize the olfactory detection of Boar Taint. Three experiments are described in which we (1) evaluate the importance of training and the effect of the previous sample, (2) determine detection thresholds on strips and in fat for our panel, and (3) test priming panelists before Boar Taint evaluation. For the final evaluation of Boar Taint, we propose a consistent three-person evaluation scoring on a 0–4 scale using a final mean score of 0.5 as the cut-off for Boar Taint. This gave an optimal sensitivity of 0.81 and a specificity of 0.56 compared to chemical cut-offs. Even limited training proved useful, but priming assessors with strips did not improve the evaluation of fat samples. Detection thresholds were higher in fat compared to strips, except for indole. We recommend panelists to always smell a non-Tainted control sample after a Tainted one as a ‘reset’ mechanism, before continuing. For longitudinal studies, we additionally advise to set up an expert panel with a fixed number of assessors performing each evaluation in duplicate.

  • on farm intervention studies on reduction of Boar Taint prevalence feeding strategies presence of gilts and time in lairage
    Research in Veterinary Science, 2018
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract One of the challenges in the production of entire male pigs is the occurrence of Boar Taint. We separately tested the effect of 3 management strategies to reduce Boar Taint on respectively 2, 3, and 6 Flemish pig farms: 1) adapted feeding strategies, 2) presence of gilts in the compartment, and 3) varying lairage duration at the slaughterhouse. A commercialized feed concept resulted in a significant reduction of olfactory Boar Taint prevalence when fed for 2 weeks (T2W) compared to control (T-CON) (P = 0.030). For T2W and when fed for 3 weeks (T3W), androstenone (AND) (P = 0.002 for T2W, P = 0.029 for T3W) and skatole (SKA) (P  3 h did not significantly affect Boar Taint.

  • sensory evaluation of Boar Taint containing minced meat dry cured ham and dry fermented sausage by a trained expert panel and consumers
    Food Chemistry, 2017
    Co-Authors: Kaat Verplanken, Vicky Vercruysse, Jella Wauters, M Aluwe, Lynn Vanhaecke
    Abstract:

    Abstract One of the main issues related to entire male pigs is the occurrence of Boar Taint, an off-odour, which compromises meat consumability. In this study, odour thresholds (indole: 24–65 µg kg−1, skatole: 44–89 µg kg−1, androstenone: 121–342 µg kg−1) for the Boar Taint compounds were estimated in minced meat, dry fermented sausage and dry-cured ham. Afterwards, sensory evaluation of these products containing 10% Tainted meat (minced meat and dry fermented sausage) or moderate Boar Taint compound levels (dry-cured ham) occurred. The beneficial effect of diluting Tainted meat was demonstrated, as no significant difference in consumability was observed between gilts and 10% Tainted meat by experts as well as consumers. Also dry-curing proved a promising technique for masking Boar Taint and preventing consumer dissatisfaction. The obtained results demonstrate the applicability of the estimated thresholds in meat as a tool for identifying masking and reducing strategies on the perception of Boar Taint.

  • olfactory evaluation of Boar Taint effect of factors measured at slaughter and link with Boar Taint compounds
    Animal, 2017
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of Boar Taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in Boar Taint prevalence, (2) investigate factors measured at slaughter influencing Boar Taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of Boar Taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory Boar Taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for Boar Taint. Average Boar Taint prevalence (score 3) was 5.6 +/- 2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3 +/- 3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having Boar Taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of Boar Taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for Boar Taint than AND. There were no significant synergetic effects between Boar Taint compounds.

Frank Tuyttens - One of the best experts on this subject based on the ideXlab platform.

  • On-farm prevalence of and potential risk factors for Boar Taint.
    Animal : an international journal of animal bioscience, 2021
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract Boar Taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence Boar Taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between Boar Taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory Boar Taint prevalence was 1.8 ± 0.8%. Boar Taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less Boar Taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower Boar Taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, Boar Taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower Boar Taint prevalences. This may to some extent be explained by the negative association between Boar Taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower Boar Taint levels.

  • Developing and Understanding Olfactory Evaluation of Boar Taint.
    Animals : an open access journal from MDPI, 2020
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Trained expert panels are used routinely in Boar Taint research, with varying protocols for training of panelists and scoring methods. We describe a standardized process for training and scoring, to contribute to standardize the olfactory detection of Boar Taint. Three experiments are described in which we (1) evaluate the importance of training and the effect of the previous sample, (2) determine detection thresholds on strips and in fat for our panel, and (3) test priming panelists before Boar Taint evaluation. For the final evaluation of Boar Taint, we propose a consistent three-person evaluation scoring on a 0–4 scale using a final mean score of 0.5 as the cut-off for Boar Taint. This gave an optimal sensitivity of 0.81 and a specificity of 0.56 compared to chemical cut-offs. Even limited training proved useful, but priming assessors with strips did not improve the evaluation of fat samples. Detection thresholds were higher in fat compared to strips, except for indole. We recommend panelists to always smell a non-Tainted control sample after a Tainted one as a ‘reset’ mechanism, before continuing. For longitudinal studies, we additionally advise to set up an expert panel with a fixed number of assessors performing each evaluation in duplicate.

  • on farm intervention studies on reduction of Boar Taint prevalence feeding strategies presence of gilts and time in lairage
    Research in Veterinary Science, 2018
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract One of the challenges in the production of entire male pigs is the occurrence of Boar Taint. We separately tested the effect of 3 management strategies to reduce Boar Taint on respectively 2, 3, and 6 Flemish pig farms: 1) adapted feeding strategies, 2) presence of gilts in the compartment, and 3) varying lairage duration at the slaughterhouse. A commercialized feed concept resulted in a significant reduction of olfactory Boar Taint prevalence when fed for 2 weeks (T2W) compared to control (T-CON) (P = 0.030). For T2W and when fed for 3 weeks (T3W), androstenone (AND) (P = 0.002 for T2W, P = 0.029 for T3W) and skatole (SKA) (P  3 h did not significantly affect Boar Taint.

  • olfactory evaluation of Boar Taint effect of factors measured at slaughter and link with Boar Taint compounds
    Animal, 2017
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of Boar Taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in Boar Taint prevalence, (2) investigate factors measured at slaughter influencing Boar Taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of Boar Taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory Boar Taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for Boar Taint. Average Boar Taint prevalence (score 3) was 5.6 +/- 2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3 +/- 3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having Boar Taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of Boar Taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for Boar Taint than AND. There were no significant synergetic effects between Boar Taint compounds.

  • The effect of the MC4R gene on Boar Taint compounds, sexual maturity and behaviour in growing-finishing Boars and gilts
    Animal : an international journal of animal bioscience, 2015
    Co-Authors: A. Van Den Broeke, Marijke Aluwé, Sam Millet, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Frank Tuyttens
    Abstract:

    Societal pressure to ban surgical castration of male piglets is rising due to animal welfare concerns, thus other methods to prevent Boar Taint need to be explored. Genetic selection against Boar Taint appears to be a long-term sustainable alternative. However, as Boar Taint is linked to reproductive hormones, it is important to consider possible negative side effects such as delayed sexual maturity or changes in behaviour. We reported earlier that the melanocortin-4 receptor (MC4R) marker can be used to reduce Boar Taint levels in fat of Boars. The objective of this study was to evaluate whether MC4R marker-assisted selection for lower Boar Taint prevalence affects plasma levels of Boar Taint compounds and testosterone; sexual maturity; behaviour; skin lesions; and lameness in Boars and gilts. Using an intervention study with a 2 x 2 design, 264 Boars and gilts differing on position 893 of the MC4R gene (AA v. GG) were compared. The MC4R polymorphism did not affect the plasma concentration of either androstenone or testosterone at different time points, whereas the concentration of skatole was significantly lower (P = 0.003) and the concentration of indole tended to be lower (P = 0.074) in GG compared with AA Boars. A higher percentage of gilts of the GG genotype were in puberty at slaughter age compared with AA gilts (P < 0.001). The age of the Boars at sexual maturity (as indicated by the first positive preputial smear test) did not differ between AA and GG Boars. In contrast, weight of GG Boars at sexual maturity tended to be lower (P = 0.065). During the period from 6 weeks of age to slaughter, Boars and gilts of the GG genotype showed more playing behaviour (P = 0.015) and less passive and feeding behaviour (P = 0.003). They showed more skin lesions on their back and caudal area (P = 0.022), and tended to show more skin lesions on their head and anterior area (P = 0.093) compared with AA animals. In conclusion, the polymorphism in the MC4R gene can be used as a marker without negative effects on reproduction characteristics in Boars and gilts. Genetic selection towards a lower prevalence of Boar Taint will lead to more active pigs with more skin lesions. Management strategies may therefore be necessary to reduce skin lesions in the selected animals.

Sam Millet - One of the best experts on this subject based on the ideXlab platform.

  • On-farm prevalence of and potential risk factors for Boar Taint.
    Animal : an international journal of animal bioscience, 2021
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract Boar Taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence Boar Taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between Boar Taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory Boar Taint prevalence was 1.8 ± 0.8%. Boar Taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less Boar Taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower Boar Taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, Boar Taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower Boar Taint prevalences. This may to some extent be explained by the negative association between Boar Taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower Boar Taint levels.

  • Developing and Understanding Olfactory Evaluation of Boar Taint.
    Animals : an open access journal from MDPI, 2020
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Trained expert panels are used routinely in Boar Taint research, with varying protocols for training of panelists and scoring methods. We describe a standardized process for training and scoring, to contribute to standardize the olfactory detection of Boar Taint. Three experiments are described in which we (1) evaluate the importance of training and the effect of the previous sample, (2) determine detection thresholds on strips and in fat for our panel, and (3) test priming panelists before Boar Taint evaluation. For the final evaluation of Boar Taint, we propose a consistent three-person evaluation scoring on a 0–4 scale using a final mean score of 0.5 as the cut-off for Boar Taint. This gave an optimal sensitivity of 0.81 and a specificity of 0.56 compared to chemical cut-offs. Even limited training proved useful, but priming assessors with strips did not improve the evaluation of fat samples. Detection thresholds were higher in fat compared to strips, except for indole. We recommend panelists to always smell a non-Tainted control sample after a Tainted one as a ‘reset’ mechanism, before continuing. For longitudinal studies, we additionally advise to set up an expert panel with a fixed number of assessors performing each evaluation in duplicate.

  • on farm intervention studies on reduction of Boar Taint prevalence feeding strategies presence of gilts and time in lairage
    Research in Veterinary Science, 2018
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract One of the challenges in the production of entire male pigs is the occurrence of Boar Taint. We separately tested the effect of 3 management strategies to reduce Boar Taint on respectively 2, 3, and 6 Flemish pig farms: 1) adapted feeding strategies, 2) presence of gilts in the compartment, and 3) varying lairage duration at the slaughterhouse. A commercialized feed concept resulted in a significant reduction of olfactory Boar Taint prevalence when fed for 2 weeks (T2W) compared to control (T-CON) (P = 0.030). For T2W and when fed for 3 weeks (T3W), androstenone (AND) (P = 0.002 for T2W, P = 0.029 for T3W) and skatole (SKA) (P  3 h did not significantly affect Boar Taint.

  • olfactory evaluation of Boar Taint effect of factors measured at slaughter and link with Boar Taint compounds
    Animal, 2017
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of Boar Taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in Boar Taint prevalence, (2) investigate factors measured at slaughter influencing Boar Taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of Boar Taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory Boar Taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for Boar Taint. Average Boar Taint prevalence (score 3) was 5.6 +/- 2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3 +/- 3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having Boar Taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of Boar Taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for Boar Taint than AND. There were no significant synergetic effects between Boar Taint compounds.

  • The effect of the MC4R gene on Boar Taint compounds, sexual maturity and behaviour in growing-finishing Boars and gilts
    Animal : an international journal of animal bioscience, 2015
    Co-Authors: A. Van Den Broeke, Marijke Aluwé, Sam Millet, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Frank Tuyttens
    Abstract:

    Societal pressure to ban surgical castration of male piglets is rising due to animal welfare concerns, thus other methods to prevent Boar Taint need to be explored. Genetic selection against Boar Taint appears to be a long-term sustainable alternative. However, as Boar Taint is linked to reproductive hormones, it is important to consider possible negative side effects such as delayed sexual maturity or changes in behaviour. We reported earlier that the melanocortin-4 receptor (MC4R) marker can be used to reduce Boar Taint levels in fat of Boars. The objective of this study was to evaluate whether MC4R marker-assisted selection for lower Boar Taint prevalence affects plasma levels of Boar Taint compounds and testosterone; sexual maturity; behaviour; skin lesions; and lameness in Boars and gilts. Using an intervention study with a 2 x 2 design, 264 Boars and gilts differing on position 893 of the MC4R gene (AA v. GG) were compared. The MC4R polymorphism did not affect the plasma concentration of either androstenone or testosterone at different time points, whereas the concentration of skatole was significantly lower (P = 0.003) and the concentration of indole tended to be lower (P = 0.074) in GG compared with AA Boars. A higher percentage of gilts of the GG genotype were in puberty at slaughter age compared with AA gilts (P < 0.001). The age of the Boars at sexual maturity (as indicated by the first positive preputial smear test) did not differ between AA and GG Boars. In contrast, weight of GG Boars at sexual maturity tended to be lower (P = 0.065). During the period from 6 weeks of age to slaughter, Boars and gilts of the GG genotype showed more playing behaviour (P = 0.015) and less passive and feeding behaviour (P = 0.003). They showed more skin lesions on their back and caudal area (P = 0.022), and tended to show more skin lesions on their head and anterior area (P = 0.093) compared with AA animals. In conclusion, the polymorphism in the MC4R gene can be used as a marker without negative effects on reproduction characteristics in Boars and gilts. Genetic selection towards a lower prevalence of Boar Taint will lead to more active pigs with more skin lesions. Management strategies may therefore be necessary to reduce skin lesions in the selected animals.

Jella Wauters - One of the best experts on this subject based on the ideXlab platform.

  • On-farm prevalence of and potential risk factors for Boar Taint.
    Animal : an international journal of animal bioscience, 2021
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract Boar Taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence Boar Taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between Boar Taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory Boar Taint prevalence was 1.8 ± 0.8%. Boar Taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less Boar Taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower Boar Taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, Boar Taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower Boar Taint prevalences. This may to some extent be explained by the negative association between Boar Taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower Boar Taint levels.

  • Developing and Understanding Olfactory Evaluation of Boar Taint.
    Animals : an open access journal from MDPI, 2020
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Trained expert panels are used routinely in Boar Taint research, with varying protocols for training of panelists and scoring methods. We describe a standardized process for training and scoring, to contribute to standardize the olfactory detection of Boar Taint. Three experiments are described in which we (1) evaluate the importance of training and the effect of the previous sample, (2) determine detection thresholds on strips and in fat for our panel, and (3) test priming panelists before Boar Taint evaluation. For the final evaluation of Boar Taint, we propose a consistent three-person evaluation scoring on a 0–4 scale using a final mean score of 0.5 as the cut-off for Boar Taint. This gave an optimal sensitivity of 0.81 and a specificity of 0.56 compared to chemical cut-offs. Even limited training proved useful, but priming assessors with strips did not improve the evaluation of fat samples. Detection thresholds were higher in fat compared to strips, except for indole. We recommend panelists to always smell a non-Tainted control sample after a Tainted one as a ‘reset’ mechanism, before continuing. For longitudinal studies, we additionally advise to set up an expert panel with a fixed number of assessors performing each evaluation in duplicate.

  • on farm intervention studies on reduction of Boar Taint prevalence feeding strategies presence of gilts and time in lairage
    Research in Veterinary Science, 2018
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    Abstract One of the challenges in the production of entire male pigs is the occurrence of Boar Taint. We separately tested the effect of 3 management strategies to reduce Boar Taint on respectively 2, 3, and 6 Flemish pig farms: 1) adapted feeding strategies, 2) presence of gilts in the compartment, and 3) varying lairage duration at the slaughterhouse. A commercialized feed concept resulted in a significant reduction of olfactory Boar Taint prevalence when fed for 2 weeks (T2W) compared to control (T-CON) (P = 0.030). For T2W and when fed for 3 weeks (T3W), androstenone (AND) (P = 0.002 for T2W, P = 0.029 for T3W) and skatole (SKA) (P  3 h did not significantly affect Boar Taint.

  • sensory evaluation of Boar Taint containing minced meat dry cured ham and dry fermented sausage by a trained expert panel and consumers
    Food Chemistry, 2017
    Co-Authors: Kaat Verplanken, Vicky Vercruysse, Jella Wauters, M Aluwe, Lynn Vanhaecke
    Abstract:

    Abstract One of the main issues related to entire male pigs is the occurrence of Boar Taint, an off-odour, which compromises meat consumability. In this study, odour thresholds (indole: 24–65 µg kg−1, skatole: 44–89 µg kg−1, androstenone: 121–342 µg kg−1) for the Boar Taint compounds were estimated in minced meat, dry fermented sausage and dry-cured ham. Afterwards, sensory evaluation of these products containing 10% Tainted meat (minced meat and dry fermented sausage) or moderate Boar Taint compound levels (dry-cured ham) occurred. The beneficial effect of diluting Tainted meat was demonstrated, as no significant difference in consumability was observed between gilts and 10% Tainted meat by experts as well as consumers. Also dry-curing proved a promising technique for masking Boar Taint and preventing consumer dissatisfaction. The obtained results demonstrate the applicability of the estimated thresholds in meat as a tool for identifying masking and reducing strategies on the perception of Boar Taint.

  • olfactory evaluation of Boar Taint effect of factors measured at slaughter and link with Boar Taint compounds
    Animal, 2017
    Co-Authors: Evert Heyrman, Sam Millet, Frank Tuyttens, Lynn Vanhaecke, Bart Ampe, Steven Janssens, Nadine Buys, Jella Wauters, Marijke Aluwé
    Abstract:

    There is a commitment by the European pig sector to ban surgical castration of male piglets in the European Union in 2018. One alternative to castration is to raise entire male pigs, with an increased risk of Boar Taint. A field study was performed to: (1) evaluate inter- and intra-farm variation in Boar Taint prevalence, (2) investigate factors measured at slaughter influencing Boar Taint and (3) evaluate the relationship between sensorial scoring by a trained panel and the concentration of Boar Taint components. From 34 farms, neck fat samples were collected from all entire male pigs in at least two slaughter batches per farm (78 batches; 9167 animals). In addition to olfactory Boar Taint analysis, data were also collected on fresh skin lesions (score 0 to 3) at the slaughter line, slaughter weight, lean meat percentage, duration of transport, time spent in lairage, total delivery duration, day length, shortening of days and outdoor mean temperature. Using the hot iron method, neck fat samples were scored (eight-point scale) for Boar Taint. Average Boar Taint prevalence (score 3) was 5.6 +/- 2.5% and the mean difference between the maximum and minimum prevalence per farm was 4.3 +/- 3.2%. Androstenone (AND), skatole (SKA) and indole concentrations were measured for a subset (n=254) of the samples. According to binomial univariate mixed models, entire male pigs with a higher skin lesion score had higher odds of having Boar Taint (P=0.031), as did fatter entire male pigs (P<0.001). In the binomial multivariate mixed model lean meat percentage (P<0.001) and outdoor mean temperature (P=0.005) remained as only significant factors. Based on our results, we can conclude that these statistically significant at least partially influence the prevalence of Boar Taint. According to the binomial univariate mixed models SKA concentration in liquid fat seems a better predictor for Boar Taint than AND. There were no significant synergetic effects between Boar Taint compounds.