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Modelagem das exigências de lisina para aves de postura em crescimentoAraujo, José Anchieta de [UNESP] 18 June 2012 (has links) (PDF)
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araujo_ja_dr_jabo.pdf: 601880 bytes, checksum: 0d896bf941334a9445bf06799cb3d182 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Cresce o interesse pela elaboração de modelos capazes de estimar exigências de frangas de reposição de diferentes genótipos e idades mantidas sob diferentes condições de criação. Assim, os objetivos deste trabalho foram: (1) estimar as exigências de lisina digestível para frangas de reposição nas fases inicial (2 a 6 semanas de idade), cria (8 a 12 semanas de idade) e recria (14 a 18 semanas de idade) com base no método dose resposta; (2) estabelecer exigências de lisina para frangas de reposição em função da deposição de proteína, eficiência de utilização de lisina e idade; (3) elaborar modelos de predição para estimar as exigências de lisina digestível para aves de postura em fase de crescimento. Para atender o objetivo (1), foram ajustados modelos matemáticos às respostas de ganho de peso, conversão alimentar e deposição de protéina e gordura corporal em função da ingestão de lisina. Para o objetivo (2), foram realizados três ensaios utilizando 144 frangas Dekalb White. O nitrogênio ingerido, excretado e depositado foram obtidos pelo balanço de nitrogênio. No objetivo (3) foram utilizadas respostas de ingestão e deposições de lisina e informações do crescimento do corpo e penas. Concluiu-se que: (1) recomendam-se 188; 274 e 258 mg de lisina para frangas de reposição nas fases inicial, cria e recria, respectivamente; (2) considerando a porcentagem média da deposição proteica, recomenda-se consumos de lisina, de 225, 312 e 283 mg/dia para os ensaios I, II e III, respectivamente e (3) os modelos de predição alcançaram os objetivos para os quais foram elaborados, proporcionando estimativas compatíveis com as obtidas no manual das linhagens / There is a growing interest in developing models capable of predicting requirements of replacement pullets of different ages and genotypes kept under different husbandry conditions. The objectives of this study were: (1) estimate the digestible lysine requirements for replacement pullets in the initial stages starter (2 - 6 weeks), grower (8 - 12 weeks) and developer (14 - 18 weeks) based on dose-response method, (2) establish lysine requirements for replacement pullets on the basis of protein deposition efficiency of lysine utilization and age, (3) develop predictive models to estimate the digestible lysine requirements for laying hens in the growth phase. To meet the objective (1), mathematical models were fitted to the responses of weight gain, feed conversion and deposition of protein and fat as a function of lysine intake. For the purpose of (2), three trials were conducted using 144 Dekalb White pullets. The nitrogen ingested, excreted and deposited were obtained by the nitrogen balance. For objective (3) responses were used for lysine intake and depositions and information growth and body feathers. It was concluded that: (1) recommend to 188; 274 and 258 mg of lysine for replacement pullets in the initial stages, rearing, respectively, (2) considering the average percentage of protein deposition, recommended intakes of lysine, 225, 312 and 283 mg/day for tests I, II and III, respectively, and (3) the prediction models achieved the goals for which they were developed, providing estimates compatible with those obtained in manual of the strains
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Modelagem das exigências de lisina para aves de postura em crescimento /Araujo, José Anchieta de. January 2012 (has links)
Orientador: Nilva Kazue Sakomura / Banca: Fernando Guilherme Perazzo Costa / Banca: José Humberto Vilar da Silva / Banca: Luciano Hauschild / Banca: Alex Sandro Campos Maia / Resumo: Cresce o interesse pela elaboração de modelos capazes de estimar exigências de frangas de reposição de diferentes genótipos e idades mantidas sob diferentes condições de criação. Assim, os objetivos deste trabalho foram: (1) estimar as exigências de lisina digestível para frangas de reposição nas fases inicial (2 a 6 semanas de idade), cria (8 a 12 semanas de idade) e recria (14 a 18 semanas de idade) com base no método dose resposta; (2) estabelecer exigências de lisina para frangas de reposição em função da deposição de proteína, eficiência de utilização de lisina e idade; (3) elaborar modelos de predição para estimar as exigências de lisina digestível para aves de postura em fase de crescimento. Para atender o objetivo (1), foram ajustados modelos matemáticos às respostas de ganho de peso, conversão alimentar e deposição de protéina e gordura corporal em função da ingestão de lisina. Para o objetivo (2), foram realizados três ensaios utilizando 144 frangas Dekalb White. O nitrogênio ingerido, excretado e depositado foram obtidos pelo balanço de nitrogênio. No objetivo (3) foram utilizadas respostas de ingestão e deposições de lisina e informações do crescimento do corpo e penas. Concluiu-se que: (1) recomendam-se 188; 274 e 258 mg de lisina para frangas de reposição nas fases inicial, cria e recria, respectivamente; (2) considerando a porcentagem média da deposição proteica, recomenda-se consumos de lisina, de 225, 312 e 283 mg/dia para os ensaios I, II e III, respectivamente e (3) os modelos de predição alcançaram os objetivos para os quais foram elaborados, proporcionando estimativas compatíveis com as obtidas no manual das linhagens / Abstract: There is a growing interest in developing models capable of predicting requirements of replacement pullets of different ages and genotypes kept under different husbandry conditions. The objectives of this study were: (1) estimate the digestible lysine requirements for replacement pullets in the initial stages starter (2 - 6 weeks), grower (8 - 12 weeks) and developer (14 - 18 weeks) based on dose-response method, (2) establish lysine requirements for replacement pullets on the basis of protein deposition efficiency of lysine utilization and age, (3) develop predictive models to estimate the digestible lysine requirements for laying hens in the growth phase. To meet the objective (1), mathematical models were fitted to the responses of weight gain, feed conversion and deposition of protein and fat as a function of lysine intake. For the purpose of (2), three trials were conducted using 144 Dekalb White pullets. The nitrogen ingested, excreted and deposited were obtained by the nitrogen balance. For objective (3) responses were used for lysine intake and depositions and information growth and body feathers. It was concluded that: (1) recommend to 188; 274 and 258 mg of lysine for replacement pullets in the initial stages, rearing, respectively, (2) considering the average percentage of protein deposition, recommended intakes of lysine, 225, 312 and 283 mg/day for tests I, II and III, respectively, and (3) the prediction models achieved the goals for which they were developed, providing estimates compatible with those obtained in manual of the strains / Doutor
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Edible Environmental Enrichments in Littered Housing Systems: Do Their Effects on Integument Condition Differ Between Commercial Laying Hen Strains?Schreiter, Ruben, Damme, Klaus, Freick, Markus 23 March 2022 (has links)
The aim of this study was to investigate the effect of additional enrichment materials (EMs; pecking stones and alfalfa bales) on the occurrence of plumage damage, skin injuries, and toe injuries, with an emphasis on the possible differences between commercial hybrid strains of laying hens. During rearing (weeks 1–18, 16 compartments, 4000 pullets) and laying periods (weeks 21–72, 24 compartments, 2808 hens) in a littered housing system, EMs were permanently provided to the study groups (EXP), while control groups (CON) did not receive additional EM. In a two-factorial study design (two groups with four strains) with 351 hens per variant, the brown egg-laying Lohmann Brown classic (LB) and Bovans Brown (BB) strains as well as the white egg-laying Lohmann Selected Leghorn classic (LSL) and Dekalb White (DW) strains were investigated. Compared to the CON, the EXP showed reduced body mass during rearing (p < 0.001) and reduced albumen consistency in the laying period (p < 0.001). Regarding integument condition, the LSL in the EXP showed more toe injuries than in the CON (p = 0.018). Remarkably, genotype-environment interactions between strains and groups were evident (p < 0.001). In groups with an EM supply, plumage damage decreased in LB (p ≤ 0.033) and LSL (p ≤ 0.005) but increased in BB (p ≤ 0.003). Moreover, there were fewer skin injuries in LSL (p = 0.001) but more in BB (p = 0.001) in groups with access to EM. In view of the diverging effects between strains, future practical recommendations for laying hen husbandry should be strain-specific.:Introduction
Materials and Methods
Results
Discussions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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