Animal preferences in choice tests have frequently been used within animal welfare research to make recommendations about animal handling and husbandry. It is therefore important that these results are obtained in a way that, as far as possible, respects the behavioural capabilities of the animal. Stress has been shown to affect cognitive processes in animals and could therefore affect the decision making process. To examine the effects of stress on decision making, 16 laying hens were trained to distinguish between two different quantities of a food reward. A decision balance point was found, by increasing the cost of reaching the large reward, in lines with the theory of demand curves. Hens were then tested in a t-maze choice test with both balanced and unbalanced sets of options, with and without prior stress treatment. Choice, latency to choose, heart rate and temperatures were recorded. Hens that received stress treatment prior to their first test session were affected by this even in subsequent sessions where they did not receive stress treatment. This effect was not found in hens that first received stress treatment prior to their second test session. This shows the influence of previous experiences on animal decision making. Also, a decrease in heart rate during the decision making period was found, when making a choice between balanced options, indicating anticipation of difficulty. Additionally, this shows that physiological measurements such as heart rate could be of importance for future studies and greater understanding of underlying processes of animal decision making.

In Legehennenbeständen wurde die Schutzwirkung von vier Impfprogrammen, die der Zentralverband der Deutschen Geflügelwirtschaft e.V. empfiehlt und einer Impfung nach der Hühner-Salmonellen-Verordnung untersucht. Unterschiede in den Impfschemata konnten unter den gewählten Versuchsbedingungen nicht festgestellt werden. Eine Impfung gegen Salmonellen garantiert keine vollständige Elimination des Erregers, sondern eine Reduktion der Besiedelung der Organe sowie der Ausscheidung und der Eikontamination. Auch eine zusätzliche Impfung mit Inaktivatimpfstoffen erbrachte keinen effektiveren Schutz vor Salmonella Enteritidis und Salmonella Thyphimurium. Die Schutzwirkung einer Impfung ist am besten, wenn die Salmonellen-Exposition gering ist.

The EPA press release dated February 23, 2004 states that the three Buckeye Egg Farm facilities had the potential to emit more than a combined total of 1850 tons per year of particulate matter (PM). This number was based on flowrate calculations that were three times higher than those measured as well as a failure to include particle size distributions in the emissions calculations. The annual PM emission for each facility was approximately 35 tons per year. The EPA was unjustified in requiring Buckeye Egg Farm to obtain Title V and PSD permits as the facilities could not have met the thresholds for these permits. Engineers need to be concerned with correctly measuring and calculating emission rates in order to enforce the current regulations. Consistency among regulators and regulations includes using the correct emission factors for regulatory permitting purposes. EPA has adopted AERMOD as the preferred dispersion model for regulatory use on the premise that it more accurately models the dispersion of pollutants near the surface of the Earth than ISCST3; therefore, it is inappropriate to use the same emission factor in both ISCST3 and AERMOD in an effort to equitably regulate PM sources. For cattle feedlots in Texas, the ISCST3 emission factor is 7 kg/1000 hd-day (16 lb/1000 hd-day) while the AERMOD emission factor is 5 kg/1000 hd-day (11 lb/1000 he-day). The EPA is considering implementing a crustal exclusion for the PM emitted by agricultural sources. Over the next five years, it will be critical to determine a definition of crustal particulate matter that researchers and regulators can agree upon. It will also be necessary to develop a standard procedure to determine the crustal mass fraction of particulate matter downwind from a source to use in the regulatory process. It is important to develop a procedure to determine the particulate matter mass fraction of crustal downwind from a source before the crustal exclusion can be implemented to ensure that the exclusion is being used correctly and consistently among all regulators. According to my findings, the mass fraction of crustal from cattle feedlot PM emissions in the Texas High Plains region is 52%.

No description available.

No description available.

Incorporation of full-fat flaxseed, and to a lesser extent, canola seed in diets to produce n-3-enriched products has attracted interest in the poultry industry. However, high amounts of nonstarch polysaccharides (NSP) in oilseeds compromise their nutritive value. The objectives of the current research were to develop enzyme supplements effective in cell wall depolymerization and viscosity reduction, particularly in flaxseed; to evaluate the effects of enzyme addition and feed processing on oil utilization and egg n-3 fatty acid deposition in broiler chickens and laying hens fed oilseed-containing diets; to characterize the NSP hydrolysis products and to investigate the effects of diet type and enzyme addition on growth performance and the incidence of necrotic enteritis (NE) in broiler chickens challenged with Clostridium perfringens. Results showed that diets containing high levels of flaxseed reduced egg production and shell quality in laying hens, and impaired final body weight and feed conversion ratio (FCR) in broiler chickens. Reducing flaxseed particle size via grinding did not improve the growth performance of broiler chickens, whereas diet pelleting showed more pronounced and beneficial effects in improving the nutritive value of flaxseed, particularly when intact seeds were used. Multicarbohydrase supplementation resulted in a significant depolymerization of cell wall polysaccharides in soybean, canola and flaxseed meals, which was followed by the production of water-soluble NSP hydrolysis products, and the reduction of flax mucilage viscosity in vitro was also evident. Enzyme addition to flaxseed-containing diets improved FCR of broiler chickens and egg production performance of laying hens, and facilitated egg n-3 fatty acid deposition. The C. perfringens challenge caused intestinal NE lesions and increased the mortality of broiler chickens with the highest NE mortality and intestinal C. perfringens counts observed in those fed flaxseed-containing diets. Enzyme supplementation to diets containing high levels of water-soluble NSP (wheat/barley- or wheat/barley/flaxseed-based) facilitated post-disease compensatory growth in pathogen challenged birds. This was accompanied by a numerical reduction of intestinal C. perfringens by 1.4 log10 cfu/g in birds fed the flaxseed-containing diets. Such findings indicated that enzyme addition may be used as a nutritional strategy to reduce the risk of NE development in broiler chickens.

In Deutschland werden jährlich über 40 Millionen männliche Eintagsküken aus Legelinien aufgrund vorrangig wirtschaftlicher Interessen getötet. Dies stellt sowohl ein ethisches als auch ein tierschutzrechtliches Problem dar (ANON. 2006, IDEL 2007). Gerade vor dem Hintergrund aktueller politischer Entscheidungen (MUNLV NRW 2013, NI MELV 2014) besteht ein Bedarf an Alternativen zur Tötung männlicher Eintagsküken. Verschiedene Lösungsansätze wie z. B. das Zweinutzungshuhn (ICKEN et al. 2013) oder aber die Mast männlicher Geschwisterhühner (KAUFMANN und ANDERSSON 2013) sind derzeit aus ökonomischen und ökologischen Gründen nicht flächendeckend realisierbar. Eine weitere Möglichkeit bietet die In-ovo-Geschlechtsbestimmung. Hierbei wird das embryonale Geschlecht bereits vor dem Schlupf identifiziert; nachfolgend können die Eier mit männlichen Embryonen aussortiert werden. Um sowohl ethischen als auch tierschutzrechtlichen Aspekten Genüge zu tun, sollte die Geschlechtsidentifikation dabei vor Einsetzen des embryonalen Schmerzempfindens stattfinden (Tag 10 + 12 h der Bebrütung; CLOSE et al. 1997). Ziel der vorliegenden Arbeit war die Entwicklung einer verlässlichen Methode zur In-ovo-Geschlechtsbestimmung anhand geschlechtsspezifischer Differenzen im Hormongehalt der Allantoisflüssigkeit sieben bis zehn Tage alter Hühnerembryonen. Nachfolgend wurde der Einfluss der Geschlechtsbestimmung auf die embryonale Entwicklung, Schlupferfolg, Aufzucht sowie die Leistungsparameter der adulten Tiere analysiert. Im Rahmen der ersten Teilstudie erfolgte die Beprobung von n = 750 Eiern des Braunlegehybrids Lohmann Brown (LB, Lohmann Tierzucht GmbH, Deutschland). Der minimalinvasiven Entnahme von Allantoisflüssigkeit folgte die Untersuchung auf 17β-Östradiol (E2), Östronsulfat (E1S) und Testosteron mittels an das Haushuhn angepassten Enzymimmunoassays (ELISA). Es konnten sowohl für E2 als auch für E1S signifikante (p < 0,01) geschlechtsspezifische Differenzen in der Allantoisflüssigeit von neun und zehn Tage alten Embryonen nachgewiesen werden. Die Testosteronkonzentration hingegen zeigte an keinem der untersuchten Tage geschlechtsabhängige Unterschiede und erwies sich somit für die In-ovo-Geschlechtsbestimmung als ungeeignet. Die statistische Auswertung ergab, dass die Bestimmung von E1S eine frühere und genauere Geschlechtsidentifikation ermöglicht als die von E2. Der für E1S festgelegte Grenzwert erreicht bei neun Tage alten Embryonen eine 86%ige Sensitivität und 83%ige Spezifität. In der zweiten Teilstudie wurde die zuvor etablierte Technik der Geschlechtsbestimmung mittels E1S an 8 + 4 h (n = 2420) und 9 + 4 h (n = 2850) Tage alten Embryonen der Herkunft LB sowie an n = 150 9 + 4 h alten Embryonen des Weißlegehybrids Lohmann Selected Leghorn (LSL, Lohmann Tierzucht GmbH, Deutschland) überprüft. Das Geschlecht der 8 + 4 h Tage alten Embryonen konnte zu 84 % korrekt identifiziert werden. Dieser Wert stieg bei 9 + 4 h Tage alten Embryonen auf 98 % (LB) bzw. 100 % (LSL) an. Im Vergleich zu einer unbehandelten Kontrollgruppe (n = 5258) wurde die Schlupfrate durch die Entnahme von Allantoisflüssigkeit um 1,4 - 3,5 (LB) bzw. 12,7 Prozentpunkte (LSL) reduziert. Nachfolgend wurden 150 Tiere der Versuchsgruppe und 80 Tiere der Kontrollgruppe für eine Aufzuchtperiode von 17 Wochen eingestallt. Hierbei zeigten sich hinsichtlich des Körpergewichtes signifikante (p < 0,05) Unterschiede zwischen Versuchs- und Kontrollgruppe in Woche 4 und 6, wobei die Zunahmen in der Versuchsgruppe geringer waren. Anschließend wurde die Leistung von 120 Tieren der Versuchsgruppe und 60 Tieren der Kontrollgruppe bis Lebenswoche 33 bezüglich Legeleistung, Eigewicht, Körpergewicht sowie Futterverbrauch analysiert. Bei keinem der untersuchten Parameter konnten signifikante Unterschiede zwischen den Gruppen festgestellt werden (p > 0,05). Die Resultate der vorliegenden Arbeit zeigen, dass eine verlässliche Geschlechtsbestimmung in ovo bei 9 + 4 h Tage alten Hühnerembryonen mithilfe einer Bestimmung der E1S-Konzentration in der Allantoisflüssigkeit möglich ist; zudem ist die beschriebene Methode bei verschiedenen Legelinien anwendbar. Die Entnahme von Allantoisflüssigkeit führt zwar zu einer minimalen Reduktion der Schlupfrate, bei adulten Legehennen kommt es jedoch zu keiner Beeinträchtigung der Produktionsleistung. Demnach erfüllt das etablierte Verfahren alle Grundvoraussetzungen für eine Anwendung in kommerziellen Brütereien. Da die Geschlechtsbestimmung vor Einsetzen des embryonalen Schmerzempfindens erfolgt, kann sie somit als Grundlage für eine ethisch vertretbare Alternative zum Töten männlicher Eintagsküken angesehen werden. / In Germany about 40 million day-old male chicks are culled each year predominantly because of economic reasons. From the animal welfare as well as the ethical point of view this is a problematic situation (ANON. 2006, IDEL 2007). Particularly with regard to current political decisions (MUNVL NRW, NI MELV 2014) alternatives to the culling of male day-old chicks are required. Different approaches such as a dual-purpose breed (ICKEN et al. 2013) or the fattening of male layer-hybrids (KAUFMANN and ANDERSSON 2013) are not ubiquitous marketable at present due to economic and ecological reasons. In ovo sexing represents another option; the embryonic gender is determined before hatch and the eggs containing male embryos can be eliminated subsequently. To comply with ethical and animal welfare aspects, the sexing should take place before the onset of embryonic pain perception (embryonic day 10 + 12 h; CLOSE et al. 1997). Aim of this thesis was the development of a reliable method for in ovo gender identification with the help of sex-specific differences in the hormone concentration of the allantoic fluid of seven to ten day old chick embryos. Subsequently, the influence of gender identification on embryonic development, hatching rate, rearing as well as production performance of the adult hens was analysed. Within the first study n = 750 eggs of the brown layer-hybrid Lohmann Brown (LB; Lohmann Tierzucht GmbH, Germany) were sampled for allantoic fluid. After the minimally invasive withdrawal the allantoic fluid was analysed via enzyme immunoassays (ELISA) adapted to domestic chicken for 17β-oestradiol (E2), oestrone sulphate (E1S) and testosterone. With regard to E2 and E1S, significant (P < 0.01) sex-specific differences were observed in the allantoic fluid of nine and ten day old embryos. Testosterone on the other hand displayed no gender-related variances on any of the analysed days. Therefore, it proved to be unsuitable for gender identification using the method applied in this study. Statistical analysis showed that the analysis of E1S allows an earlier and more accurate sexing than the E2-assay. The limit value determined for E1S has a sensitivity of 86 % and a specificity of 83 % for nine day old embryos. The previously established method for gender identification via E1S detection in the allantoic fluid was verified with a larger number of samples in the second study. The allantoic fluid of day 8 + 4 h (n = 2420) and day 9 + 4 h (n = 2850) old LB embryos as well as n = 150 day 9 + 4 h old embryos of the white layer-hybrid Lohmann Selected Leghorn (LSL; Lohmann Tierzucht GmbH, Germany) was analysed. For day 8 + 4 h old embryos the sex was correctly identified in 84 %. The accuracy of gender prediction increased for day 9 + 4 h old embryos up to 98 % (LB) and 100 % (LSL). Compared to an untreated control group (n = 5258) sampling of allantoic fluid reduced the hatching rate by 1.4 - 3.5 (LB) and 12.7 points of percentage (LSL). In the following, 150 animals of the experimental group and 80 animals of the control group were reared for a period of 17 weeks. With regard to the body weight significant differences (P < 0.05) were observed in weeks 4 and 6, with the animals of the experimental group having a lower body weight. Subsequently the production performance of 120 hens from the experimental and 60 hens from the control group was analysed up to an age of 33 weeks. With respect to egg production, egg weight, body weight and feed consumption no significant differences (P > 0.05) were observed between the groups. The results of this thesis demonstrate that a reliable in ovo sexing of day 9 + 4 h old chicken embryos is possible via the measurement of E1S in the allantoic fluid; additionally the method is not limited to a certain layer strain. The sampling of allantoic fluid reduces the hatching rate only marginally. The production performance of adult hens on the other hand is not affected. Therefore, the described technique fulfils all the basic requirements for an alternative method to the culling of day-old male layer chicks. Because gender identification takes place before the onset of embryonic pain perception it can serve as the basis for an ethical alternative to the culling of male day-old chicks from layer-hybrids.

Incorporation of full-fat flaxseed, and to a lesser extent, canola seed in diets to produce n-3-enriched products has attracted interest in the poultry industry. However, high amounts of nonstarch polysaccharides (NSP) in oilseeds compromise their nutritive value. The objectives of the current research were to develop enzyme supplements effective in cell wall depolymerization and viscosity reduction, particularly in flaxseed; to evaluate the effects of enzyme addition and feed processing on oil utilization and egg n-3 fatty acid deposition in broiler chickens and laying hens fed oilseed-containing diets; to characterize the NSP hydrolysis products and to investigate the effects of diet type and enzyme addition on growth performance and the incidence of necrotic enteritis (NE) in broiler chickens challenged with Clostridium perfringens. Results showed that diets containing high levels of flaxseed reduced egg production and shell quality in laying hens, and impaired final body weight and feed conversion ratio (FCR) in broiler chickens. Reducing flaxseed particle size via grinding did not improve the growth performance of broiler chickens, whereas diet pelleting showed more pronounced and beneficial effects in improving the nutritive value of flaxseed, particularly when intact seeds were used. Multicarbohydrase supplementation resulted in a significant depolymerization of cell wall polysaccharides in soybean, canola and flaxseed meals, which was followed by the production of water-soluble NSP hydrolysis products, and the reduction of flax mucilage viscosity in vitro was also evident. Enzyme addition to flaxseed-containing diets improved FCR of broiler chickens and egg production performance of laying hens, and facilitated egg n-3 fatty acid deposition. The C. perfringens challenge caused intestinal NE lesions and increased the mortality of broiler chickens with the highest NE mortality and intestinal C. perfringens counts observed in those fed flaxseed-containing diets. Enzyme supplementation to diets containing high levels of water-soluble NSP (wheat/barley- or wheat/barley/flaxseed-based) facilitated post-disease compensatory growth in pathogen challenged birds. This was accompanied by a numerical reduction of intestinal C. perfringens by 1.4 log10 cfu/g in birds fed the flaxseed-containing diets. Such findings indicated that enzyme addition may be used as a nutritional strategy to reduce the risk of NE development in broiler chickens.

Zur Klimagestaltung in Legehennenställen werden primär Unterdrucklüftungssysteme mit einem Luftwechsel nach dem Strahllüftungsprinzip entlang der Querachse des Stalls eingesetzt. Zur besseren Frischluftversorgung im Tierbereich werden zunehmend Unterdrucklüftungssysteme mit einem Luftwechsel nach dem Tunnelprinzip entlang der Längsachse des Stalls eingesetzt. Im Projekt werden die beiden Luftwechselvarianten verglichen, um Kenndaten zu ausgewählten Stallraumlasten sowie zum Luft- und Volumenstrom für die Varianten zu bestimmen und hieraus Bewertungen zu Staub-, Geruchs- und Ammoniakemissionen abzuleiten. Die Ammoniakemissionen sind bei der Tunnellüftung gegenüber Strahllüftung niedriger, die Staubemissionen sind dagegen bei der Strahllüftung geringer. Für die Geruchsemissionen wurden keine Unterschiede festgestellt. Die Voliereblöcke erzeugen im Stallraum Strömungsbarrieren und werden von der Frischluft weitgehend umströmt. Hierdurch entstehen deutliche Luftwechselunterschiede zwischen dem frei durchströmbaren Stallraum und dem Innenbereich der Voliereblöcke.

The aim of the thesis was comparing production parameters of laying hens breeding in different housing systems at a production enterprise, it means in enriched cages and aviary. There is used the laying hybrid ISA Brown for production consumer eggs. The achievement during 13months' cycle shown that in each laying month except 1st laying month the higher hen-day egg production was fond out by hens in enriched cages. The hen-egg production per month was higher in enriched cages too. The higher mortality was demonstrated by hens in aviary during all laying months. Both housing systems reached the highest mortality in the 13th laying month. The hens in aviary had higher feed consumption per egg during all months. Higher daily feed consumption was assigned by the hens in the aviary in the 1st, 2nd and 3rd month and from the 9th to the 13th laying month. In other laying months the hens in enriched cages had higher daily feed consumption. Feed costs formed the highest entry of total costs.