Papers by Frank André Maurice Tuyttens
HAL (Le Centre pour la Communication Scientifique Directe), Aug 24, 2008
Journal of Mammalogy, Aug 27, 1999
Estimates of abundance of medium-to-large mammals by traditional mark-recapture models may be unr... more Estimates of abundance of medium-to-large mammals by traditional mark-recapture models may be unreliable because quantity and quality of trapping data are low. The proposed closed-subpopulation model provides a flexible framework to increase the amount of data used for estimation of demographic parameters, by taking into account characteristics of the population and using ancillary non-trapping data. This model defines a subsection of the population that is known to be alive and within the study area during a certain period, regardless of which animals were actually caught. Population size is estimated from the proportion of animals in this closed subpopulation that were actually captured. We used this model to estimate size of a partly culled population of Eurasian badgers (Meles meles). Number of badgers included in the closed subpopulation was maximized by using data from trapping, road-traffic accidents, and radiotelemetry, and by assuming that no additions occurred to the population of young between trapping occasions. Probabilities of capture varied by season and age-class but not sex, trapping, or radio-tagging. Population estimates appeared reliable because estimated number of times individual badgers were trapped in a year corresponded with observed frequencies and estimated size of the young and adult popUlations corresponded favorably with estimates based on a mark-resight procedure.
Journal of Animal Ecology, Sep 1, 2000
1. The spatial organization of a badger population (North Nibley) is described before and after i... more 1. The spatial organization of a badger population (North Nibley) is described before and after it was subjected to a UK Ministry of Agriculture, Fisheries and Food badger removal operation (BRO) intended to control bovine tuberculosis. Comparison is made with an undisturbed badger population (Woodchester Park). 2. The Woodchester Park population was organized in group territories with clearly de®ned boundaries that remained stable during the 3 years of study (1995± 97). In North Nibley, however, the badgers' spatial organization was severely perturbed in the ®rst year and, to a lesser extent, also in the second year after the BRO, with badgers using latrines further away from their setts. This resulted in enlarged social group ranges that were dicult to de®ne and overlapped considerably. 3. The disturbance was observed in the removal groups, those immediately adjacent, as well as those at a distance of one or two social groups from the removal area, with an unexpected indication that the latter groups may have been the most aected. 4. The apparent increase in the size of the group ranges in North Nibley was likely to have been caused by an increased proportion of badgers making extra-group excursions in the aftermath of the BRO. 5. Initial recolonization was almost exclusively by females. 6. Although such perturbation might be expected to facilitate disease transmission between badger social groups, there was no evidence that any infectious animals had survived the BRO. However, there were further cattle breakdowns in the area. 7. The behaviour of badgers after the BRO also provided an opportunity to test predictions made by competing hypotheses about the main determinants of the badger's socio-spatial behaviour.
Worlds Poultry Science Journal, 2006
Meat Science, May 1, 2013
No automated detection system for boar taint detection is currently available, thus boar taint at... more No automated detection system for boar taint detection is currently available, thus boar taint at the slaughterline can currently only be assessed using the singeing method (olfactory scoring). This study compares several heating methods (microwave, soldering iron and pyropen) and evaluates the effect of habituation, cleaning the soldering iron, singeing the fat twice in the same place, and variations in the technical procedures. All methods seem to be suitable for detecting boar taint but the choice of heating method for sensory scoring of boar taint depends on habituation of the trained assessor and specific conditions applied. The pyropen seems to be most suitable because it does not contact the fat and is easy to handle (wireless). Finally, the intensity score may also be influenced by: contamination from not cleaning the soldering iron, singeing the fat twice in the same place, and the effect of habituation.
Meat Science, Dec 1, 2012
Three potential early-age predictors of which boars are likely to develop boar taint (testes volu... more Three potential early-age predictors of which boars are likely to develop boar taint (testes volume, skin lesions and dirtiness) were measured on 102 boars every fortnight from 10 weeks of age until slaughter. These predictors were correlated with the level of boar taint according to the hot iron method and the concentrations of skatole and androstenone as determined by chemical analysis. The chance of no/low boar taint according to the hot iron method decreased with higher testes volume (weeks 22 and 24) and increased with skin lesion score (weeks 12, 16 and 18). For the concentrations of androstenone and skatole, the strongest correlation was found with testes volume in week 12. Skin lesions in week 16 were negatively correlated with skatole levels. Dirtiness was negatively correlated with skatole concentrations (week 18) but positively correlated with androstenone concentrations (weeks 20 and 22). Testes volume has the greatest potential for predicting the likelihood of developing boar taint.
Meat Science, Jul 1, 2011
Skatole and androstenone are the main boar taint compounds. Whereas nearly everybody is sensitive... more Skatole and androstenone are the main boar taint compounds. Whereas nearly everybody is sensitive to skatole, the sensitivity to androstenone is genetically determined and differs between countries. In this study the methodology for testing androstenone sensitivity was refined and applied to 1569 consumers that were approached at six shopping malls in Flanders. Participants were asked to smell the contents of four bottles (three were filled with water and one with androstenone solved in water) and to identify and describe the odour of the strongest smelling bottle. This test was performed twice. 45.3% of the respondents were classified as sensitive to androstenone (i.e. the percentage of participants that identified the correct bottle in both tests minus a guess correction). Sensitivity differed between sexes (men: 38.3%-women: 51.1%, P b 0.001), according to age (older people were less sensitive, P b 0.001), and between the test locations (P b 0.001), but not between smokers versus non-smokers.
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Papers by Frank André Maurice Tuyttens