A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.

A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.

Four experiments were conducted to evaluate guar meal as a source of prebiotic galactomannans for laying hens. In the 1st experiment, late phase laying hens were fed diets with 0, 5, 10% guar meal (GM) for 56 days or 15% GM for 28 days then switched to the 0% GM diet for the final 28 days. In the 2nd experiment, young pullets were fed guar germ (GG) or GM at 0, 2.5 or 5% for 20 weeks. In the 1st and 2nd experiments, egg production and feed consumption were not affected by feeding up to 5% guar by-products whereas feed efficiency was decreased by guar feeding. Feeding of GG or GM did not affect egg weight or shell quality, but decreased the egg yolk color and Haugh units. Guar increased absolute and relative liver weight, but did not affect the weights of the pancreas, spleen, or the incidence of fatty liver or liver hemorrhage. Feeding 10% GM depressed feed consumption and increased body weight loss. Feeding 15% GM severely depressed egg production followed by a recovery of production after returning to 0% GM feeding. In the 3rd and 4th experiments, late phase laying hens were induced to molt by feed withdrawal (FW) or feeding 15 or 20% GM with or without &#946;-mannanase (Hemicell??). All hens except those fed 15% GM with enzyme obtained a complete cessation of lay in 10 days. Compared to FW birds, hens fed GM had lower body weight reduction and mortality, while hens fed 20% GM with enzyme had higher post-molt egg production. Salmonella enteritidis (SE) present in 6 organs (crop, liver, spleen, ovary, oviduct and cecum), and SE in cecal contents were significantly reduced by 20% GM feeding with and without enzyme. The results showed that GG or GM can be safely fed to laying hens up to 5% without adverse effects on performance. An alternative molting method employing 20% GM with or without &#946;-mannanase is preferable to FW because GM feeding results in a complete molt and decreases mortality, as well as enhances the resistance to SE of molted hens.

Das Ziel kontinuierlicher Messungen über zwei Jahre war die Bewertung der Stickstoffdepositionen und Ammoniakimmissionen einer Bodenhaltung (Voliere) mit Auslauf für 20.000 Hennen auf das Umfeld. Untersucht wurden weiterhin die Staub- und Geruchskonzentrationen in Stall- und Abluft. Die untersuchte Bodenhaltung emittiert im Jahr 41 g Ammoniak je Tierplatz. Die Vergleiche 14-tägiger Messdatenreihen zeigen, dass Emissionsmessungen an Tierhaltungen in möglichst langen Zeitfenstern und mindestens viermal jährlich durchzuführen sind. Die Immissionswerte für Ammoniak sind 40 m vom Stall am höchsten und erreichen nach ca. 350 m wieder das Hintergrundniveau am Standort. Unter Abzug der nicht dem Stall zuzurechnenden Hintergrundkonzentrationen verursacht der Stall im Nahbereich (40 m) eine Stickstoffdeposition von 18 kg/ha. Ab 230 m Distanz werden nur noch ca. 3 kg/ha deponiert. Die mittlere Tageskonzentration der Staubgehalte im Abluftstrom wurde in Abhängigkeit vom Außenklima zwischen 1,2 und 9,0 mg/m³ ermittelt. Der Anteil von PM-10 und PM-2.5 am Gesamtstaub betrug 80 bzw. 30 %. Für Gesamtstaub wurde ein Emissionsfaktor von 145,4 g/Tpl. zur Berechnung der Jahresemissionen ermittelt. Die in den Außenklimabereichen ermittelten Geruchsstoffkonzentrationen (Geruchsschwelle) im Abluftstrom liegen zwischen 25 und 115 GE/m³. Die mittleren Referenzwerte der Außenluft liegen bei 19 GE.

The aim of this work was to investigate the effects of feather availability and imprinting to loose feathers in the litter on the incidence of feather pecking behaviour (FP), condition of the integument and fear reactions in two genotypes of laying hens. Hens that were deprived from loose feathers in the litter (feathers were collected 4 times/week) exhibited a significantly less rate of feather pecking, less number of severe FP and showed a better feather score in the laying period compared to the control groups (no feather treatment) in both Lohmann Tradition (LT) & Lohmann Silver (LS) genotypes. Addition of brown feathers to the floor in LT hens (feathers were added once/week) was associated with a reduction in feather pecking rate, the severe form of this behaviour and improved plumage and skin conditions. Contrary, the addition of white feathers to the floor in LS was associated with the highest rate of feather pecking, the highest severe form of this behaviour as well as the worst feather and skin conditions in the laying period compared to other groups of the same genotype. The LT birds in all feather treatments had a better feather cover than the LS birds. Hens that were imprinted to loose feathers in the litter in the rearing period exhibited a higher rate of FP, higher number of severe FP and showed the worst feather and skin conditions when feathers were collected from the floor during the laying period. Also, these hens reacted more fearful during the tonic immobility test. It is concluded that loose feathers may play a role in the development of feather pecking behaviour in laying hens. Large differences between genotypes were found in respect to the availability of loose feathers, feather pecking and plumage and integument condition. Imprinting of chicks to loose feathers from the floor may affect the incidence of feather pecking later on. Ziel dieser Arbeit war es, die Einflüsse des Federangebotes und der Prägung auf lose Federn in der Einstreu auf die Häufigkeit des Auftretens von Federpicken (FP), den Zustand des Integuments und die Furchtreaktionen an zwei Legehennengenotypen zu untersuchen. Hühnern beider untersuchter Genotypen (Lohmann Tradition (LT) und Lohmann Silber (LS)), denen die losen Federn 4 mal/ Woche aus der Einstreu abgesammelt wurden, zeigten eine geringere Federpickrate, eine geringere Anzahl der schweren Form des FP und eine bessere Gefiederbeschaffenheit in der Legeperiode verglichen mit der Kontrollgruppe (keine Federbehandlung). Das Hinzufügen brauner Federn zur Einstreu bewirkte bei LT Hennen eine Reduktion der FP-Rate, der schweren Form des Federpickens und verbesserte die Gefieder- und Hautbeschaffenheit. Dagegen führte das Hinzufügen weißer Federn in die Einstreu während der Legeperiode bei LS Hennen zur höchsten Federpickrate und Anzahl der schweren Form des Federpickens sowie zur schlechtesten Gefieder- und Hautbeschaffenheit im Vergleich zu anderen Gruppen des gleichen Genotyps. Hühner der LT Linie wiesen in allen Federbehandlungen eine bessere Befiederung als die LS Hühner auf. Hennen, die während der Aufzuchtsperiode auf lose Federn in der Einstreu geprägt wurden, zeigten nach Absammeln der Federn während der Legeperiode eine erhöhte FP-Rate mit einer erhöhten Anzahl der schweren Form des FP und die schlechteste Gefieder- und Hautbeschaffenheit. Außerdem reagierten diese Hühner ängstlicher während des Tests auf tonische Immobilität. Es kann geschlussfolgert werden, dass lose Federn in der Einstreu eine Rolle bei der Entwicklung des Federpickverhaltens von Legehennen spielen und dass Federpicken als Futtersuchverhalten interpretiert werden kann. Grosse Unterschiede zwischen den Genotypen bestanden hinsichtlich der Verfügbarkeit von losen Federn in der Einstreu, des Federpickens sowie der Gefieder- und Integumentbeschaffenheit. Eine Prägung der Junghennen auf lose Federn in der Einstreu könnte das Auftreten von Federpicken zu einem späteren Zeitpunkt beeinflussen.

Orientador: Angelo Berchieri Júnior / Banca: Antonio Carlos Alessi / Banca: Nilce Maria Soares Queiroz Gama / Resumo: Devido ao grande número de casos de toxinfecção alimentar e aos prejuízos sócio-econômicos causados pela Salmonella Enteritidis aos seres humanos, tornam-se necessário estudos sobre a prevenção e controle desta bactéria nos plantéis avícolas. Assim, o objetivo deste trabalho foi a análise do emprego de bacterinas inativadas oleosas contra Salmonella enterica sorovar Enteritidis (SE) em aves de postura comercial, visando prevenir a excreção fecal e a contaminação dos ovos. Foram utilizadas três formulações de bacterinas comerciais de SE em emulsão oleosa. As aves foram vacinadas na oitava e décima sexta semana de idade e foi mantido um grupo de aves sem vacinação (controle). Na vigésima semana de idade, treze aves de cada tratamento foram desafiadas com uma dose oral de aproximadamente 109 células viáveis de SE fagotipo 4 (resistente ao ácido nalidíxico e a espectomicina), sendo que este procedimento foi repetido na vigésima quinta e trigésima primeira semanas de idade. A eficácia das vacinas empregadas foi conferida através de exames laboratoriais, para pesquisa de SE no conteúdo cecal, baço, ovário e ovos. A vacinação conferiu proteção parcial contra colonização de SE no ceco e contra eliminação da bactéria nas fezes e nos ovos, portanto, recomenda-se que o uso das bacterinas seja complementado com outras formas de controle para SE. / Abstract: Due to the great number of outbreaks of food poisoning and the socioeconomic issues caused to the human beings by the Salmonella Enteritidis, it becomes necessary the study on the prevention and control of this bacterium in the poultry flocks. Thus, the objective of this work was the analysis of the use of bacterins against Salmonella Enteritidis infection in commercial birds, aiming to prevent the fecal excretion and the contamination of eggs. Have been used three Salmonella Enteritidis oil-emulsion commercial bacterins formulations. The laying hens were vaccinated in the eighth and sixteenth weeks old and one group of birds was kept as nonvacinated control. On twentieth weeks ago, thirteen birds of each treatment were challenged with an oral dose of approximately 109 viable cells of phage type 4 Salmonella Enteritidis (resistant to the acid nalidixic and the espectomicin), this procedure was repeated in the twentieth fifth and thirtieth first weeks ago. The efficacy of employed vaccines was conferred through laboratorial examinations, for research of SE from fecal samples, spleen, ovary and eggs. The vaccination conferred partial protection against caecal colonization and against shedding of SE in the feces and eggs, therefore, it is recommended that the use of the killed bacterins be complemented with other forms of SE control. / Mestre

Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-31Bitstream added on 2014-06-13T20:17:35Z : No. of bitstreams: 1 moura_amg_me_jabo.pdf: 217826 bytes, checksum: a7582335f0d6673050625302eb64e73a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Devido ao grande número de casos de toxinfecção alimentar e aos prejuízos sócio-econômicos causados pela Salmonella Enteritidis aos seres humanos, tornam-se necessário estudos sobre a prevenção e controle desta bactéria nos plantéis avícolas. Assim, o objetivo deste trabalho foi a análise do emprego de bacterinas inativadas oleosas contra Salmonella enterica sorovar Enteritidis (SE) em aves de postura comercial, visando prevenir a excreção fecal e a contaminação dos ovos. Foram utilizadas três formulações de bacterinas comerciais de SE em emulsão oleosa. As aves foram vacinadas na oitava e décima sexta semana de idade e foi mantido um grupo de aves sem vacinação (controle). Na vigésima semana de idade, treze aves de cada tratamento foram desafiadas com uma dose oral de aproximadamente 109 células viáveis de SE fagotipo 4 (resistente ao ácido nalidíxico e a espectomicina), sendo que este procedimento foi repetido na vigésima quinta e trigésima primeira semanas de idade. A eficácia das vacinas empregadas foi conferida através de exames laboratoriais, para pesquisa de SE no conteúdo cecal, baço, ovário e ovos. A vacinação conferiu proteção parcial contra colonização de SE no ceco e contra eliminação da bactéria nas fezes e nos ovos, portanto, recomenda-se que o uso das bacterinas seja complementado com outras formas de controle para SE. / Due to the great number of outbreaks of food poisoning and the socioeconomic issues caused to the human beings by the Salmonella Enteritidis, it becomes necessary the study on the prevention and control of this bacterium in the poultry flocks. Thus, the objective of this work was the analysis of the use of bacterins against Salmonella Enteritidis infection in commercial birds, aiming to prevent the fecal excretion and the contamination of eggs. Have been used three Salmonella Enteritidis oil-emulsion commercial bacterins formulations. The laying hens were vaccinated in the eighth and sixteenth weeks old and one group of birds was kept as nonvacinated control. On twentieth weeks ago, thirteen birds of each treatment were challenged with an oral dose of approximately 109 viable cells of phage type 4 Salmonella Enteritidis (resistant to the acid nalidixic and the espectomicin), this procedure was repeated in the twentieth fifth and thirtieth first weeks ago. The efficacy of employed vaccines was conferred through laboratorial examinations, for research of SE from fecal samples, spleen, ovary and eggs. The vaccination conferred partial protection against caecal colonization and against shedding of SE in the feces and eggs, therefore, it is recommended that the use of the killed bacterins be complemented with other forms of SE control.

Orientador: Carlos Ducatti / Banca: Ariel Antonio Mendes / Banca: Marcelo Zacharias Moreira / Banca: José Roberto Sartori / Banca: Fabiana Ribeiro Caldara / Resumo:O estudo objetivou rastrear a inclusão de farinha de carne e ossos bovina (FCOB) em dietas de poedeiras comerciais, por meio da análise dos ovos e suas frações (gema e albúmen), pela técnica dos isótopos estáveis do carbono e nitrogênio, assim como avaliar o índice analítico mínimo detectável. Foram utilizadas 240 galinhas poedeiras da linhagem Shaver White de 73 semanas de idade, em delineamento experimental inteiramente casualizado, com cinco tratamentos e seis repetições. Os tratamentos consistiram de níveis de inclusão (0; 1,5; 3,0; 4,5 e 6,0%) de FCOB na dieta a base de milho e farelo de soja. No 35º dia foram tomados aleatoriamente 24 ovos por tratamento, dos quais 12 serviram para amostragem de gema e albúmen e os outros 12 para ovo (gema + albúmen). Os resultados isotópicos foram submetidos à análise multivariada de variância e a partir das matrizes de erro, com 95% de confiança, foram determinadas elipses para identificar as diferenças entre os tratamentos experimentais (dietas com FCOB) e o grupo controle (0% de FCOB). No ovo e na gema a partir do par isotópico do tratamento com inclusão de 3,0% de FCOB houve diferenciação do par do tratamento controle, no albúmen a diferenciação ocorreu a partir do tratamento com 1,5% de FCOB. Conclui-se que, a técnica dos isótopos estáveis é capaz de rastrear a FCOB, utilizada na alimentação de poedeiras, no produto final, em nível mínimo de inclusão de 1,5% no albúmen e 3,0% no ovo e na gema. / Abstract: The aim of this study was to trace the inclusion of bovine meat and bones meal (BMBM) in diets of laying hens analyzing eggs and theirs fractions (yolk and albumen), by carbon (δ13C) and nitrogen (δ15N) stable isotopes, as well as to evaluate the detectable analytical minimal index. Two hundred forty (240) Shaver White laying hens aging 73 weeks never fed with animal origin ingredients were randomly distributed in five treatments and fed with a corn and soybean based diet (control) and four increasing levels (0; 1.5; 3.0; 4.5 and 6.0%) of BMBM. At the 35th day, 24 eggs per treatment were randomly collect, twelve for yolk and albumen sampling and twelve for egg (yolk + albumen) sampling. The isotopic results were analyzed in a multivariate analysis of variance. Through an error matrix (95% confidence) the ellipses were determined to identify the differences among the treatments (diets BMBM inclusion) from the control group (0% BMBM group). It was possible to detect BMBM inclusion through the isotopic pair of yolk and egg at 3.0% of inclusion. In the albumen it was possible to detect the 1.5% BMBM inclusion. In summary, the stable isotopes technique is able to trace BMBM in laying hens feed, in the final product at a minimal level of inclusion of 1.5% in the albumen and 3.0% in the egg and yolk. / Doutor

<p dir="ltr">Due to increasing legislative and societal demand for humane egg production, an increased production of cage-free eggs is inevitable. Past research has focused on the impact of cage-free housing systems (CFS) on laying hens' performance, health, and space use; however, limited studies have examined the impacts of CFS on the behavioral activities of laying hens, particularly in single-tier floor systems in the U.S. Broadly, this research examined the influence of two housing systems on the behavior of laying hens as they age. Specifically, the study aimed to provide information on how dissimilar cage-free systems meet the behavioral needs of laying hens. </p><p dir="ltr">Two hundred pullets were randomly assigned to either a single-tier floor room (SFR) or a modified multi-tier aviary room (MAR) at 17 weeks of age (WOA), where they remained until 85 WOA. Starting at 55 WOA, thirty focal birds were marked with non-toxic markers for individual identification in each room. The behavior of the birds was recorded continuously over two consecutive days during the mid-laying (55 WOA) and late-laying (85 WOA) phases. The behavioral expressions of the focal birds were annotated using 10-min continuous sampling at 5 time points (10 minutes after lights-on (TOD 1), 4 hr after lights-on (TOD 2), 8hr after lights-on (TOD 3), 12 hr after lights-on (TOD 4), and 10 minutes before lights-off (TOD 5)). At each of these 5 time points, 4 birds were randomly selected for observation. Behavior duration and frequency data were analyzed using PROC GLIMMIX in SAS 9.4, with the main effects of housing system (HS), age, and time of day (TOD). Descriptive statistics were used to present the behavioral time budgets of marked and unmarked birds in MAR and SFR. Further, the behaviors performed in different spatial zones (areas within each room) were presented as the percentage of observed time laying hens spent engaged in a specific behavior over the total time at a particular spatial zone. </p><p dir="ltr">Birds in MAR and SFR spent most of the observed time perching at all ages. The birds (marked and unmarked) performed environmental pecking and foraging for the highest percentage of time in the litter area of SFR and MAR. Similarly, the percentage of time the birds (marked and unmarked) spent preening and performing OCB (wing flapping, stretching, and feather-ruffling) was highest when they occupied the litter zone of MAR and SFR. Housing system influenced the time that both marked and unmarked birds spent performing foraging and environmental pecking (EP) such that marked and unmarked birds in SFR spent more time engaged in these behaviors than marked and unmarked birds in MAR (Marked: SFR vs. MAR, P = 0.043; Unmarked: SFR vs. MAR, P = 0.002). Further, marked and unmarked birds in SFR exhibited a higher frequency of EP than birds in MAR (Marked: SFR vs. MAR, P = 0.02; Unmarked: SFR vs. MAR, P < 0.001). The frequency of locomotion (standing and walking) activity differed between SFR and MAR birds. Birds (marked and unmarked) stood more frequently in SFR than in MAR (Marked: SFR vs. MAR, P = 0.046; Unmarked: SFR vs. MAR, P < 0.001). Further, SFR birds had a higher walking frequency than MAR birds (Marked: P = 0.003; Unmarked: P = 0.02). Birds (marked and unmarked) in MAR perched more frequently than SFR birds (Marked: SFR vs. MAR, P < 0.001; Unmarked: SFR vs. MAR, P = 0.01); however, unmarked birds preened more frequently in SFR than in MAR (P < 0.001). Regarding time of day, both marked and unmarked birds exhibited higher preening frequency 10 mins after lights-on (TOD 1) than at other times of day (P < 0.001). Similarly, marked birds perched for a longer duration early in the morning (TOD 1) and late at night (TOD 5), than at TOD 2 and TOD 3 (P < 0.001). </p><p dir="ltr">This study revealed that MAR and SFR may differ in how they accommodate the behavioral needs of laying hens, with hen activity levels varying between the two types of housing systems. Further research is needed to understand the implications of behavioral outcomes for the welfare of laying hens in different types of CFS.</p>

L’alimentation séquentielle (AS) consiste à distribuer de manière cyclique deux aliments différents dont la combinaison permet des apports nutritionnels adaptés. L’objectif de la thèse était d’évaluer la robustesse et les limites de ce système. Trois expérimentations ont étéréalisées. Les questions portaient sur la variation de la composition en matières premières des régimes, la capacité d’adaptation des poules à des situations de déséquilibre alimentaire et de stress thermique et enfin la modulation au cours de la journée des apports en énergie et en protéines. Un travail de méta-analyse apportait des réponses sur la régulation de l’ingestion chez les poules pondeuses ainsi que sur l’impact de la nature des ingérés sur les performances de ponte et de croissance. Les expérimentations (Ex.1, 2, 3) ont permis de mettre en évidence la possibilité de distribuer d’autres céréales (blé et/ou maïs broyé, fibres insolubles) à la place du blé entier distribué dans la fraction du matin. L’ingestion totale inférieure par rapport à une alimentation continue (Ex. 1 et 2) et un niveau de production équivalent permettent d’améliorer l’IC des poules en AS par rapport à des poules alimentée de façon classique. Les poules semblent capables de réguler leur ingestion sur le niveau d’énergie de l’aliment mais pas sur son niveau de protéines dans les conditions étudiées (méta-analyse, Ex. 2). Cependant, les apports en énergie doivent se concentrer dans la fraction du matin afin d’obtenir les meilleures performances en AS tandis que les apports protéiques doivent soit être concentrés dans la fraction de l’après midi soit continus au cours de la journée (Ex. 3). Ces connaissances sur l’AS doivent encore être complétées afin de pouvoir utiliser ce système d’alimentation en élevage néanmoins l’AS est prometteur en terme d’économies de ressources. / Sequential feeding (SF) consists in splitting the nutrients into two different diets. The goal of this thesis was to explore the limits of this feeding system. Three experiments were performed. The major questions go on utilization of other feedstuffs, capacity of hens to adapt their feed intake on unbalanced diet and hot temperatures and responses to modulation of energy and protein supplies. A meta-analysis gave responses on the regulation of feed intake and the impact on nutrient intake on laying and growth performances in laying hens. Experiments (Ex.1, 2, 3) shown off the possibility to substitute whole wheat with other cereals or feedstuffs (ground wheat and/or corn, insoluble fiber) in the morning fraction. Lower total feed intake in SF compared to continuous feeding (Ex. 1 et 2) and same laying performances improved the FCR. Laying hens were able to fit their feed intake on energy in the diet but not on protein content (meta-analysis, Ex. 2). Nevertheless, energy supplies had to be given in the morning fraction while protein could be given concentrate in the afternoon or throughout the day (Ex. 3). Knowledge on SF has to be completed in order to use this feeding system in commercial conditions. SF can help sparing resources and improve the on farm economical efficiency.