Kevin Kress

Mr. Kevin Kress


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 June 2019 in Sustainability
Verified
Journal Article
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KKKevin Kress
Kevin Kress
SMSam Millet
Sam Millet
ÉLÉtienne Labussière
Étienne Labussière
UWUlrike Weiler
Ulrike Weiler
VSVolker Stefanski
Volker Stefanski
Immunocastration, a technique to replace surgical castration of piglets, consists of two consecutive vaccinations to induce antibodies which transiently suppress testicular functions and avoid boar taint. It is a method to ensure both a high product quality and a high level of animal welfare. The impact of immunocastration on the three pillars of sustainability has been studied extensively. While all aspects of sustainability have been studied separately, however, a contemporary global overview of different aspects is missing. In immunocastrates, performance results are better than in barrows, but worse than in boars. The environmental impact of pork production with immunocastrates is lower than with barrows, but higher than with boars. The level of aggression is considerably lower in immunocastrates compared to boars. Societal concerns are mainly related to food safety, and are not supported by scientific evidence. After second vaccination, immunocastrates switch from a boar- to a barrow-like status. Therefore, the timing of second vaccination is a fine-tuning tool to balance advantages of boars with environmental and economic benefits against increased risk of welfare problems and boar taint. Nevertheless, both synergic and conflicting relationships between the pillars of sustainability must be communicated along the value chain to produce tailored pork products.

28 September 2020 in Animals
Verified
Journal Article
Open access
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MAMarijke Aluwé
Marijke Aluwé
EHEvert Heyrman
Evert Heyrman
João M. AlmeidaJoão M. Almeida
João M. Almeida
JBJakub Babol
Jakub Babol
Gianni BattaconeGianni Battacone
Gianni Battacone
MEMacarena Egea
Macarena Egea
Surgical castration of piglets without pain relief is still common practice in many countries. Possible alternatives for surgical castration are application of pain relief or anaesthesia or production of boars (entire males) and immunocastrates. Each of these alternatives faces advantages and disadvantages which may result in different citizen attitudes and consumers acceptability. Understanding which practice is acceptable to whom and why may further stimulate implementation. Consumer (n = 3251) and stakeholder (n = 1027) attitudes towards surgical castration without pain relief, surgical castration with anaesthesia, immunocastration, and production of boars were surveyed from April to June 2020 via an online questionnaire in 16 countries (>175 respondents per country). Surgical castration without pain relief was separated from each of the alternatives due to animal welfare and showed the lowest acceptability (32%). Within the alternatives, a further partitioning between the alternatives was based on perceived quality and food safety, with an acceptance of 85% for applying anaesthesia, 71% for immunocastration, and 49% for boar production. Differences depending on professional involvement and familiarity with agriculture could be observed, mainly for the acceptance of surgical castration without anaesthesia, immunocastration, and boars. Castration with anaesthesia was highly accepted by all types of respondents.

21 December 2019 in Animals
Verified
Journal Article
Open access
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KKKevin Kress
Kevin Kress
UWUlrike Weiler
Ulrike Weiler
SSSonja Schmucker
Sonja Schmucker
MČMarjeta Čandek-Potokar
Marjeta Čandek-Potokar
MVMilka Vrecl
Milka Vrecl
VSVolker Stefanski
Volker Stefanski
Immunocastration is a sustainable alternative to piglet castration but faces limited market acceptance. The phenomenon of non-responders has not to date been examined in detail, but adverse and stressful housing conditions (e.g., mixing of groups) might impair the success of vaccinations. Therefore, we evaluated the influence of housing conditions on the immune response after two Improvac® vaccinations at an age of 12 and 22 weeks, respectively. Boars, immunocastrates and barrows (n = 48 each) were assigned to three different housing conditions (n = 36 enriched, n = 36 standard n = 72 repeated social mixing). Immune response was quantified by measuring GnRH-binding and its consequences for testosterone concentrations, development of the genital tract and boar taint. Growth performance was evaluated via average daily gain (ADG). GnRH-binding and testosterone levels revealed that immunocastration reliably suppressed testicular functions after the 2nd vaccination. Housing conditions did not modify testicular function but influenced ADG as animals under mixing grew slower than those under enriched conditions. Gonadal status had only a slight impact on ADG except in immunocastrates, which showed a temporarily higher ADG after the 2nd vaccination. The results show that immunocastration is a reliable procedure under different housing conditions and competitive in terms of growth performance.

18 September 2019 in Agriculture
Verified
Journal Article
Open access
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KKKevin Kress
Kevin Kress
MVMandes Verhaagh
Mandes Verhaagh
From 2021 onwards, surgical castration of male piglets without pain relief will be banned in Germany. In Europe, stakeholders have committed themselves to end piglet castration from 2018 onwards. Alternatives to surgical castration are pork production with boars or immunocastrates. The competitiveness of these production systems is required to increase their market acceptance. The aim of this study was to test the profitability of pork production with boars and immunocastrates under different carcass pricing systems and penalty systems linked to boar taint. The calculations were based on the performance parameters of 36 animals (n = 12 immunocastrates, n = 12 boars, n = 12 barrows) from an experimental study. In order to analyze the economic effects of both alternatives under different regional German production systems, the performance data were set in relation to the data of agri benchmark. Both boars and immunocastrates performed economically worse than barrows in all the scenarios tested. If immunocastrates are sold according to the boar pricing system, the profitability of this technique is even lower, but still more profitable than boar fattening. Pork production with boars is the most unprofitable alternative in this study and will be further devalued if a penalty system linked to boar taint will be introduced.

19 October 2020 in Animals
Verified
Journal Article
Open access
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KKKevin Kress
Kevin Kress
JHJens Hartung
Jens Hartung
JJJohannes Jasny
Johannes Jasny
VSVolker Stefanski
Volker Stefanski
UWUlrike Weiler
Ulrike Weiler
The surgical castration of male piglets as a routine procedure in modern pig production is facing increasing societal criticism. Pork production with boars and immunocastrates are available alternatives, but both have low market shares as it is so far uncertain how the carcass characteristics and primal pork cuts of boars and immunocastrates will be estimated in comparison to barrows and gilts. This article therefore evaluates the impact of sex group (gilts, boars, immunocastrates and barrows) on carcass characteristics and primal pork cuts using AutoFOM III data from a commercial abattoir. In our study, weekly slaughter data from a total of n = 36,994 pigs between 2018 and 2019 were analyzed. The results show that gilts had the highest amount of pork per carcass of all sex groups, whereas non-significant differences between boars, immunocastrates and barrows could be observed. Boars had the highest lean meat content, followed by gilts, immunocastrates and finally barrows with the lowest lean meat content. These results suggest that both immunocastration and pork production with boars are sustainable techniques that can replace pork production with barrows without affecting carcass quality.

3 February 2020 in Animals
Verified
Journal Article
Open access
PDF file
MČMarjeta Čandek-Potokar
Marjeta Čandek-Potokar
MŠMartin_Skrlep Škrlep
Martin_Skrlep Škrlep
EKEliza Kostyra
Eliza Kostyra
SZSylwia Zakowska-Biemans
Sylwia Zakowska-Biemans
KPKlavdija Poklukar
Klavdija Poklukar
VSVolker Stefanski
Volker Stefanski
Alternative solutions to the surgical castration of piglets need to be assessed because this is a particularly sensitive issue for the processing of traditional pork products. Currently, the available information about the advantages and drawbacks of castration for dry-cured products is limited; thus, the objective of this study was to evaluate the quality of Slovenian dry-cured ham (Kraški pršut) from entire males (EM), immunocastrates (IC) and surgical castrates (SC). Hams (12 per sex group) were processed for one year and physical-chemical, rheological and sensory analysis of the dry-cured hams was performed. With regard to processing aptitude, the main difference was in the subcutaneous fat thickness, which influenced the level of dehydration and salt intake. This was further reflected in the physical-chemical traits and the texture, which were measured instrumentally or assessed by panelists. Regarding the aforementioned traits, EM and IC were generally similar and different from SC. On the contrary, sensory profiling of odor, taste and flavor demonstrated that EM had the lowest overall sensory quality, different from both IC and SC, and presented odors and flavors described as sweat, manure, sharp and persistent. We confirmed that dry-curing did not eliminate the perception of boar taint in the product from EM. The IC were similar in many aspects to EM except for the odor, taste and flavor of dry-cured hams, in which case they were more similar to SC.