Productive performance of white leghorn hens based on the type of housing during rearing: floor versus cage

Poultry farmers in the southeastern of Mexico consider that the productivity of the hens that comes from rearing on floor has a higher productive performance than reared hens in cages, mainly due to higher percentage of egg laying and lower mortality. The aim of this study was to evaluate the productive performance of the laying hen in relation to the type of rearing. A total of 79680 pullets Bovans White of 17 weeks of age were housed in cages with five pullets cage-1 (405 cm2pullet-1). They were divided in two treatments according to their type of rearing (floor vs cage) with four replicates. The study period was from week 20 to week 40 of age. The variables evaluated were daily (%) and cumulative mortality (%), egg production (%), egg weight (g), feed intake (g pullet d-1), cumulative feed intake (g pullet-1), daily and cumulative egg mass, number of eggs per hen housed, egg loss (%) and productivity index. The variables were analyzed using a randomized block design. It was observed that daily and cumulative mortality, feed intake and egg loss was higher (p < 0.05), while the number of eggs per hen housed and productivity index (p < 0.05) was lower for hens in cages. We conclude that it is possible to associate detriments in the productive performance of laying hens based on the type of housing during its growth phase.

Productive performance of white leghorn hens based on the type of housing during rearing: floor versus cage

Poultry farmers in the southeastern of Mexico consider that the productivity of the hens that comes from rearing on floor has a higher productive performance than reared hens in cages, mainly due to higher percentage of egg laying and lower mortality. The aim of this study was to evaluate the productive performance of the laying hen in relation to the type of rearing. A total of 79680 pullets Bovans White of 17 weeks of age were housed in cages with five pullets cage-1 (405 cm2pullet-1). They were divided in two treatments according to their type of rearing (floor vs cage) with four replicates. The study period was from week 20 to week 40 of age. The variables evaluated were daily (%) and cumulative mortality (%), egg production (%), egg weight (g), feed intake (g pullet d-1), cumulative feed intake (g pullet-1), daily and cumulative egg mass, number of eggs per hen housed, egg loss (%) and productivity index. The variables were analyzed using a randomized block design. It was observed that daily and cumulative mortality, feed intake and egg loss was higher (p < 0.05), while the number of eggs per hen housed and productivity index (p < 0.05) was lower for hens in cages. We conclude that it is possible to associate detriments in the productive performance of laying hens based on the type of housing during its growth phase.(AU)

Growth Performance, Organ Weights and Some Blood Parameters of Replacement Laying Pullets Fed with Increasing Levels of Wheat Bran

This study was conducted to determine the growth performance, organ weights, and selected blood parameters of replacement laying pullets (development phase) fed increasing levels of wheat bran (WB). A total of 240 70-d-old White Leghorn pullets (Hybrid L33) were evaluated for seven weeks. Birds were assigned to three dietary treatments according to a completely randomized design. Treatments consisted of diets containing 100 (T1), 150 (T2), or 200 g/kg (T3) of WB in partial replacement of corn, with 10 replicates per treatment of eight birds per replicate. Birds fed T2 presented higher body weight (p 0.05) compared with T1 and T3 (1112.52 to 1163.35 g). Also, T2 birds presented higher methionine plus cystine intake relative to T1 (0.38 to 0.40 g/bird/day). Likewise, a higher inclusion of WB (200 g/kg) increased crude fiber (2.29 to 2.63 g/bird/day) and crude fat (1.98 to 3.58 g/bird/day) intakes (p 0.05). However, the experimental treatments did not affect the relative weight of the organs or small intestine and cecum length (p>0.05). Serum concentration of triacylglycerols, cholesterol, calcium, phosphorus, hematocrit, or hemoglobin levels were not significantly different (p>0.05) among treatments. These findings indicate a beneficial effect of use of 150 g/kg of wheat bran on the growth performance of pullets during the development phase; however, the inclusion of this cereal up to 200 g/kg had no effect on organ weights and blood parameters.(AU)

Growth Performance, Organ Weights and Some Blood Parameters of Replacement Laying Pullets Fed with Increasing Levels of Wheat Bran

This study was conducted to determine the growth performance, organ weights, and selected blood parameters of replacement laying pullets (development phase) fed increasing levels of wheat bran (WB). A total of 240 70-d-old White Leghorn pullets (Hybrid L33) were evaluated for seven weeks. Birds were assigned to three dietary treatments according to a completely randomized design. Treatments consisted of diets containing 100 (T1), 150 (T2), or 200 g/kg (T3) of WB in partial replacement of corn, with 10 replicates per treatment of eight birds per replicate. Birds fed T2 presented higher body weight (p 0.05) compared with T1 and T3 (1112.52 to 1163.35 g). Also, T2 birds presented higher methionine plus cystine intake relative to T1 (0.38 to 0.40 g/bird/day). Likewise, a higher inclusion of WB (200 g/kg) increased crude fiber (2.29 to 2.63 g/bird/day) and crude fat (1.98 to 3.58 g/bird/day) intakes (p 0.05). However, the experimental treatments did not affect the relative weight of the organs or small intestine and cecum length (p>0.05). Serum concentration of triacylglycerols, cholesterol, calcium, phosphorus, hematocrit, or hemoglobin levels were not significantly different (p>0.05) among treatments. These findings indicate a beneficial effect of use of 150 g/kg of wheat bran on the growth performance of pullets during the development phase; however, the inclusion of this cereal up to 200 g/kg had no effect on organ weights and blood parameters.

CRESCIMENTO PONDERAL E BIOMÉTRICO DE POEDEIRAS LEVES POR MEIO DO MODELO DE GOMPERTZ: MODELAGEM DAS VARIÂNCIAS E DENSIDADES DE CRIAÇÃO

BRUSAMARELO, EMANUELE. Crescimento ponderal e biométrico de poedeiras leves por meio do modelo de Gompertz: modelagem das variâncias e densidades de criação. 2020. 65 f. Tese (Doutorado em Ciência Animal) Faculdade de Agronomia e Zootecnia, Universidade Federal de Mato Grosso, Cuiabá, 2020. Objetivou-se predizer o crescimento ponderal e biométrico de poedeiras leves por meio do modelo de Gompertz e modelagem das variâncias. Para isso, dois experimentos foram conduzidos. No primeiro experimento, com duração de 112 dias, para a fase de cria (1 a 14 dias de idade), 2500 pintainhas com um dia de idade (Hyline W-36) foram pesadas individualmente e distribuídas, em delineamento inteiramente casualizado (DIC), em cinco densidades de 100,00; 105,66; 112,00; 119,15 e 127,27 cm2/ave, com dez repetições cada. Para a fase de recria (15 a 112 dias de idade), 750 frangas (Hyline W-36) foram pesadas individualmente e distribuídas em DIC, em cinco densidades de 294,74; 329,41; 373,33; 430,77 e 509,09 cm2/ave, com dez repetições cada. As aves receberam rações formuladas para atender às exigências nutricionais de cada fase, sendo ração e água fornecidas ad libitum. Os dados de massa corporal e idade de poedeiras leves criadas em diferentes densidades populacionais foram obtidos com 1, 7, 14, 21, 28, 42, 56, 70, 84, 98 e 112 dias de idade. As análises estatísticas foram realizadas no programa computacional estatístico SAS (Statistical Analysis System, University Edition), por meio do procedimento para modelos não lineares mistos, com o nível de significância estabelecido em p<0,01, em todas as análises. No segundo ensaio, 280 pintainhas, com um dia de idade (Hyline W-36) foram distribuídas em gaiolas metálicas e acompanhadas até 140 dias de idade. Para o ajuste da densidade de criação, o período experimental foi dividido em três etapas de 1 a 14; 15 a 112 e 113 a 140 dias de idade. As rações foram formuladas para atender às exigências das aves. A ração e a água foram disponibilizadas ad libitum. Semanalmente, todas as aves das gaiolas foram pesadas. Dentre estas, cinco aves com peso médio foram selecionadas e empregadas nas análises. As aves foram sacrificadas por meio de deslocamento cervical e em seguida, amostras de penas foram coletadas. A coleta de penas sucedeu à evisceração direcionada para a biometria de órgãos. Os dados observados de 1 a 140 dias de idade de poedeiras leves foram utilizados nas análises. No experimento 1, a partir dos resultados das avaliações dos multimodelos obtidos pela combinação de Gompertz e funções de variância, conclui-se que, para descrever o crescimento de poedeiras leves em diferentes densidades, o modelo de Gompertz e função de variância escalonada, comum para as densidades de criação, explica melhor o comportamento da variância da variável dependente massa corporal das aves em relação ao tempo. Na análise de verificação de significância dos parâmetros nas diferentes densidades, as estimativas das médias dos parâmetros de massa assintótica, de taxa de crescimento e de tempo (dias) não foram interferidas pelas diferentes densidades de criação de poedeiras leves. Curvas de crescimento de poedeiras leves em diferentes densidades, ajustadas e ilustradas graficamente por meio do modelo unânime, apresentam aspecto sigmoide e as ajustadas por meio da derivada, detalham os incrementos em ganhos de massa. No experimento 2, nas avaliações dos multimodelos obtidos pela combinação do modelo de Gompertz e associação de funções de variância, para mais da metade das variáveis dependentes, o modelo unânime foi Gompertz e função de variância escalonada. Assim, conclui-se que, para descrever o crescimento corporal, de penas e de órgãos de poedeiras leves, o modelo de Gompertz e função de variância escalonada explica melhor o comportamento da variância das variáveis massa corporal com ou sem penas, massa de penas, massa de fígado, de proventrículo, de coração e de intestino grosso total, enquanto que, a função de variância exponencial elucida melhor o comportamento da variância das variáveis moela, intestino delgado total e pâncreas das aves. Curvas de crescimento corporal, de penas e de órgãos de poedeiras leves ajustadas e ilustradas graficamente por meio do respectivo modelo unânime, apresentam aspecto sigmoide e as ajustadas por meio da derivada, detalham os ganhos em massa para cada variável.

BRUSAMARELO, EMANUELE. Ponderal and biometric growth of lightweight laying hens through the Gompertz model: modeling of the variances and creation densities. 2020. 65 p. Thesis (Ph.D. in Animal Science) Faculdade de Agronomia e Zootecnia, Universidade Federal de Mato Grosso, Cuiabá, 2020. The objective was to predict the ponderal and biometric growth of lightweight laying hens through the Gompertz model and modeling of the variances. For this, two experiments were conducted. In the first experiment, with lasting 112 days, for start phase (1 to 14 days of age), 2500 one-day-old female chicks (Hyline W-36) were weighed individually and distributed, in a completely randomized experimental design, in five densities of 100.00; 105.66; 112.00; 119.15 and 127.27 cm2/bird, with ten repetitions each. For the rearing phase (15 to 112 days old), 750 pullets (Hyline W-36) were weighed individually and distributed in a completely randomized design in five densities of 294.74; 329.41; 373.33; 430.77 and 509.09 cm2/bird, with ten repetitions each. The birds were given rations formulated to meet the nutritional requirements of each phase, with ration and water provided ad libitum. The Body mass and age data of lightweight laying hens reared at different population densities were obtained at 1, 7, 14, 21, 28, 42, 56, 70, 84, 98, and 112 days of age. The statistical analyses were performed in the SAS (Statistical Analysis System, University Edition) software, through the procedure for mixed nonlinear models, with the level of significance established at p<0.01, in all analyses. In the second trial, 280 one-day-old female chicks (Hyline W-36) were distributed in metal cages and accompanied until 140 days old. For the adjusted rearing density, the experimental period was divided into three stages from 1 to 14; 15 to 112 and 113 to 140 days of age. The rations were formulated to meet the requirements of the birds. The ration and the water were made available ad libitum. Weekly, all the birds in the cages were weighed. From these, five birds with average weight were selected and employed in the analyses. The birds were sacrificed by cervical dislocation and then samples of feathers were collected. The collection of feathers followed evisceration directed at organ biometry. The data observed from 1 to 140 days of the age of lightweight laying hens were used in the analysis. In experiment 1, from the results of the evaluations of the multi models obtained by the combination of Gompertz and functions of variance, it is concluded that to describe the growth of lightweight laying hens in different densities, the model of Gompertz and function of staggered variance, common for the densities of rearing, better explain the behavior of the variance for body mass the birds. In the significance check analysis of the parameters in the different densities, the estimates of the averages of the parameters of asymptotic mass, growth rate, and time (days) were not interfered with by the different densities rearing of lightweight laying hens. Growth curves of lightweight laying hens in different densities, adjusted and graphically illustrated through the unanimous model, have a sigmoid aspect and those adjusted through the derivative, detail the increases in mass gains. In experiment 2, in the evaluations of multi models obtained by combining the Gompertz model and the association of functions of variance, for more than half of the dependent variables, the unanimous model was Gompertz and function of stepped variance. Thus, it is concluded that to describe the growth of body, feather, and organs of lightweight laying hens, the Gompertz model and function of staggered variance better explain the behavior of variance of the variables body mass with or without feathers, feather mass, liver mass, proventriculus mass, heart mass, and total large intestine, while the function of exponential variance better elucidates the behavior of variance of the variables gizzard, total small intestine, and pancreas of birds. Body growth curves, of feather and organs of lightweight laying hens, adjusted and graphically illustrated through the respective unanimous model, present sigmoid aspect and those adjusted through the derivative, detail the mass gains for each variable.

FORMAS DE APRESENTAÇÃO, SISTEMAS DE ALIMENTAÇÃO E NÍVEIS DE ENERGIA EM DIETAS PARA POEDEIRAS SEMIPESADAS NAS FASES DE CRESCIMENTO E POSTURA

O objetivo deste estudo foi avaliar o efeito de dietas com diferentes formas de apresentação (farelada x peletizada), sistemas de alimentação (a vontade x controlado) e níveis de energia metabolizável (recomendado x reduzido) sobre o desempenho zootécnico e a qualidade de ovos de poedeiras semipesadas em um ciclo completo de produção (cria, recria e postura). Foram utilizadas 400 poedeiras em delineamento inteiramente casualizado com 8 tratamentos em arranjo fatorial 2 x 2 x 2 com 5 repetições de 10 aves. Foi avaliado de 7 a 12 semanas e de 13 a 17 semanas o desempenho zootécnico (consumo de ração, peso vivo, conversão alimentar e uniformidade). Na fase de produção foram avaliados o desempenho zootécnico (consumo de ração, peso vivo, produção e peso de ovos, conversão alimentar); qualidade de ovos (espessura de casca, unidade Haugh, rendimentos de casca, gema e albúmen, peso de órgãos (ovário, oviduto, sistema digestório), pH da moela e índice de gordura abdominal. Na fase de cria as formas de apresentação, sistemas de alimentação e níveis de energia não apresentaram diferença significativa para conversão alimentar (kg/Kg), houve diferença significativa (p<0,05) no sistema de alimentação para consumo (g/ave/dia) e peso (g), onde a alimentação a vontade apresentou maior consumo e peso vivo da ave. A uniformidade apresentou interação nas formas de apresentação e sistemas de alimentação, onde a farelada a vontade apresentou melhor uniformidade e a peletizada controlada apresentou a pior uniformidade. Na fase de recria as formas de apresentação, sistemas de alimentação e níveis de energia não apresentaram diferença significativa (p>0,05) para o peso vivo e a conversão alimentar (Kg/Kg). O consumo de ração (g/ave/dia) apresentou interação entre formas de apresentação e sistemas de alimentação, onde o sistema controlado apresentou menor consumo para farelada e peletizada e a uniformidade (%) apresentou interação entre formas de apresentação e sistemas de alimentação onde a ração peletizada e a vontade obteve maior uniformidade do lote. Na fase de postura houve interação entre formas de apresentação e sistemas de alimentação, as aves alimentadas com ração peletizada e a vontade apresentaram o maior consumo (g/ave/dia) e o sistema controlado apresentou o menor consumo sem diferença entre a forma de apresentação, resultado semelhante foi encontrado na interação entre sistemas de alimentação e níveis de energia, onde o sistema a vontade apresentou maior consumo pelas aves e não diferiu no sistema controlado de fornecimento de ração. A produção ovos teve interação entre sistemas de alimentação e os níveis de energia, onde a pior índice de postura foi apresentado pelo sistema controlado e baixa energia. Conversão alimentar apresentou 3 formas de interações sendo que o melhor resultado foi observado com a utilização de ração farelada com energia reduzida e fornecida de forma controlada. O sistema de alimentação controlado não se mostrou vantajoso em nenhuma fase de produção. Ração peletizada não é recomendada para aves poedeiras na fase de cria e na fase recria associada ao sistema de alimentação controlado. Redução no nível de energia metabolizável de 2800 Kcal/kg para 2550 Kcal/kg associado ao sistema de fornecimento de alimento controlado na fase postura acarretará em redução na porcentagem de postura e no peso do ovo.

This study was conducted in order to evaluate the effect of diets with differents types of presentantion (mash X pelletized), feeding system ( ad libitum x controlled) and metabolisable energy level value (recommened x reduced) in the zootechnical performance and egg quality of semi heavy laying hens in a complete cycle of production (rearing and laying phase). 400 laying hens were distributed in a experiment completely randomized with 8 treatments arranged as a 2 × 2 × 2 factorial with 10 hens and 5 repetitions. The zootechnical performance (feed intake, body weight, feed conversion and uniformity) was evaluated from 7 to 12 weeks and from 13 to 17 weeks. In the egg laying period, the zootechnical performance (feed intake, body weight, egg production and egg weight, egg mass, feed conversion ratio) were evaluated; Egg quality (shell thickmess, Haugh units, egg shell, yolk and albumen yield, organ weight (ovary, oviduct, digestive system), gizzard pH and abdominal fat yield.In the raising phase the forms presentation, feeding system and energy levels, there was no significant difference (p <0.05) to feed conversion ratio (kg/kg), and (P<0,05) to daily feed intake (g/hen/day) and body weight (g), where ad libitum system presented a higher daily feed intake and body weight. The body uniformity showed interaction in the forms of presentation and feeding systems, where the ad libitum mash ration has a better uniformity and controlled pelletized ration was the inferior uniformity. In the rearing phase, the presentation forms, feeding systems and energy levels presented no significant difference (p> 0.05) for body weight and feed conversion ratio (kg / kg). Daily feed consumption (g/hen/day) presented interaction between forms presentation and feeding systems, where the controlled system presented lower consumption for mash and pelleted ration and the body uniformity (%) showed interaction between forms presentation and feeding systems where the ad libitum pelletized ration obtained greater uniformity. In the egg production phase, there was interaction between the forms presentation and feeding system, the hens fed with pelleted feed presented highest daily feed intake (g/hen/day) and the controlled system showed the lowest consumption without difference between the presentation forms, a similar result was found in the interaction between feeding systems and energy levels, where the system presented higher consumption by the hen and did not differ in the controlled system. The eggs production interacted between feeding systems and energy levels, where the worst posture index presented by the controlled system and low energy. Feed conversion ratio showed three forms of interactions and the best result was observed with the use of mash ration, low energy and provided in a controlled feed system. The controlled feed system did not prove to be advantageous at any production phase. Pelleted ration is not recommended for pullet in the rearing phase associated with the controlled feed system. Reduction in the metabolizable energy level from 2800 Kcal/kg to 2550 Kcal/kg associated with the controlled feeding system in the laying phase will lead to a reduction in the percentage of laying and egg weight.

Beak-trimming methods and their effect on the performance of japanese quail pullets (Coturnix japonica)

This study aimed at verifying if beak-trimming methods in Japanese quail pullets could optimize production by decreasing stress caused by cannibalism. A total number of 816 day-old Japanese quails was distributed in a completely randomized experimental design in a 2 x 3 factorial arrangement, with two beak-trimming ages (14 and 21 days of age) and three beak-trimming sizes (not trimmed, 1/3 trimmed, or 1/2 trimmed), and 4 replicates of 34 birds per replicate. Birds were submitted to the same management and feeding conditions. Weight gain, feed intake, feed conversion ratio, and mortality were evaluated. There was no significant effect of age at beak trimming on the evaluated parameters (P>0.05), as well as no significant interaction between age at beak trimming, and beak-trimming method. There was a significant effect (P 0.01) of trimming size on performance, with the best performance observed in birds not submitted to beak trimming or had 1/2 of the beak trimmed. When the beak was more aggressively trimmed (1/2), parameters were worse. According to the obtained results, it is recommended to trim 1/3 of the beaks, which can be performed either at 14 or 21 days of age.

Beak-trimming methods and their effect on the performance of japanese quail pullets (Coturnix japonica)

This study aimed at verifying if beak-trimming methods in Japanese quail pullets could optimize production by decreasing stress caused by cannibalism. A total number of 816 day-old Japanese quails was distributed in a completely randomized experimental design in a 2 x 3 factorial arrangement, with two beak-trimming ages (14 and 21 days of age) and three beak-trimming sizes (not trimmed, 1/3 trimmed, or 1/2 trimmed), and 4 replicates of 34 birds per replicate. Birds were submitted to the same management and feeding conditions. Weight gain, feed intake, feed conversion ratio, and mortality were evaluated. There was no significant effect of age at beak trimming on the evaluated parameters (P>0.05), as well as no significant interaction between age at beak trimming, and beak-trimming method. There was a significant effect (P 0.01) of trimming size on performance, with the best performance observed in birds not submitted to beak trimming or had 1/2 of the beak trimmed. When the beak was more aggressively trimmed (1/2), parameters were worse. According to the obtained results, it is recommended to trim 1/3 of the beaks, which can be performed either at 14 or 21 days of age.

Productive performance of Japanese quail (Coturnix coturnix japonica) submitted to different beak-trimming densities and types - DOI: 10.4025/actascianimsci.v27i1.1263 / Desempenho produtivo de codornas japonesas (Coturnix coturnix japonica) submetidas a diferentes densidades e tipos de debicagem - DOI: 10.4025/actascianimsci.v27i1.1263

This experiment evaluated the effects of beak-trimming in japanese quail pullet phase development; and of beak-trimming combined to different housing densities on their laying performance. For the pullet phase, the experiment had a randomized design with three treatments (absent, soft and severe debeaking), each with sixteen-birds repetition. For the laying phase, the experiment had randomized design with factorial scheme, with six treatments: three beak trimmings (absent, soft and severe), two densities (75 cm2/bird or 103 cm2/bird) and four repetitions, with 16 or 22 birds per cage. The results in pullet phase showed that quails submitted to absent or soft beak trimming had better weigh at the pullet phases end, but hard beak trimming did not affect sexual maturity. During the laying phase, hard beak-trimming resulted in low mortality and better feed conversion, independently of density. This work results showed the advisability of beak trimming

Avaliou-se o efeito da debicagem em codornas japonesas sobre o desenvolvimento na recria e a debicagem combinada com diferentes densidades de alojamento sobre o desempenho na postura. Na recria, o delineamento experimental foi inteiramente casualizado, com 3 tratamentos (aves não-debicadas, debicadas levemente ou severamente) com 10 repetições de 16 aves cada. Na postura, o delineamento foi inteiramente casualizado em esquema fatorial, com 6 tratamentos: 3 tipos de debicagem (nenhuma, leve e severa) e 2 densidades (75 cm2/ave e 103 cm2/ave) e 4 repetições, com 16 e 22 aves por parcela. Os resultados da fase de recria mostram que as aves submetidas a nenhuma debicagem ou a leve apresentaram melhor peso no final da recria, porém a debicagem severa não afetou a maturidade sexual. Na fase de postura, a debicagem severa resultou em menor mortalidade e desperdício de ração, independentemente da densidade. Conclui-se que a debicagem deve ser realizada

Productive performance of Japanese quail (Coturnix coturnix japonica) submitted to different beak-trimming densities and types - DOI: 10.4025/actascianimsci.v27i1.1263 / Desempenho produtivo de codornas japonesas (Coturnix coturnix japonica) submetidas a diferentes densidades e tipos de debicagem - DOI: 10.4025/actascianimsci.v27i1.1263

This experiment evaluated the effects of beak-trimming in japanese quail pullet phase development; and of beak-trimming combined to different housing densities on their laying performance. For the pullet phase, the experiment had a randomized design with three treatments (absent, soft and severe debeaking), each with sixteen-birds repetition. For the laying phase, the experiment had randomized design with factorial scheme, with six treatments: three beak trimmings (absent, soft and severe), two densities (75 cm2/bird or 103 cm2/bird) and four repetitions, with 16 or 22 birds per cage. The results in pullet phase showed that quails submitted to absent or soft beak trimming had better weigh at the pullet phases end, but hard beak trimming did not affect sexual maturity. During the laying phase, hard beak-trimming resulted in low mortality and better feed conversion, independently of density. This work results showed the advisability of beak trimming

Avaliou-se o efeito da debicagem em codornas japonesas sobre o desenvolvimento na recria e a debicagem combinada com diferentes densidades de alojamento sobre o desempenho na postura. Na recria, o delineamento experimental foi inteiramente casualizado, com 3 tratamentos (aves não-debicadas, debicadas levemente ou severamente) com 10 repetições de 16 aves cada. Na postura, o delineamento foi inteiramente casualizado em esquema fatorial, com 6 tratamentos: 3 tipos de debicagem (nenhuma, leve e severa) e 2 densidades (75 cm2/ave e 103 cm2/ave) e 4 repetições, com 16 e 22 aves por parcela. Os resultados da fase de recria mostram que as aves submetidas a nenhuma debicagem ou a leve apresentaram melhor peso no final da recria, porém a debicagem severa não afetou a maturidade sexual. Na fase de postura, a debicagem severa resultou em menor mortalidade e desperdício de ração, independentemente da densidade. Conclui-se que a debicagem deve ser realizada

Desempenho e qualidade de ovos de poedeiras de 50 a 66 semanas de idade suplementadas com probiótico

The experiment was carried out to evaluate probiotic on laying hen performance and egg quality. The probiotic was fed from pullet phase and the effects were evaluate from 50 to 66 weeks. A completely randomized experimental design with four treatments (probiotic suplementation in pullet and laying phase, probiotic suplementation only in pullet phase, probiotic suplementation only in laying phase and no suplementation), and six replicates of eight birds each was used. The rations contained 15.50 and 17.00% crude protein and 2800 and 2750kcal metabolizable energy/kg respectively in pullet and laying phases. The results of feed intake (106.53, 110.81, 107.25, 109,72g), egg production (85.20, 83.66, 79.18, 81.94%), egg weight (59.84, 60.53, 61.11, 60.33g), alimentary conversion per dz (1.50, 1.59, 1.64, 1.61), and per kg (2.09, 2.19, 2.24, 2.22), shell thickness (0.387, 0.384, 0.386, 0.381mm), shell percent (9.44, 9.43, 9.37, 9.31%), Haugh unit (92.50, 93.14, 91.34, 91.57) and specific gravity (1.0856, 1.0851, 1.0850, 1.0839) did not indicate any treatment effect (P>0.05). The utilization of Bacillus subtilis as probiotic during pullet phase, laying phase or pullet and laying phases did not improve the performance and egg quality of laying hens from 50 to 66 weeks of age.

Objetivou-se, com este trabalho, avaliar o efeito de probiótico sobre o desempenho e qualidade de ovos de poedeiras. A suplementação de probiótico foi iniciada na fase de recria e os efeitos foram avaliados de 50 a 66 semanas. O delineamento experimental adotado foi inteiramente ao acaso com quatro tratamentos (suplementação de probiótico na fase de recria e postura, suplementação de probiótico somente na fase de recria, suplementação de probiótico somente na fase de postura e ausência de suplementação) e seis repetições de oito aves cada. Nas fases de recria e postura, as rações continham 15,50 e 17,00% de proteína bruta e 2800 e 2750kcal de energia metabolizável/kg. Os resultados de consumo de ração (106,53, 110,81, 107,25, 109,72g), produção de ovos (85,20, 83,66, 79,18, 81,94%), peso de ovos (59,84, 60,53, 61,11, 60,33g), conversão alimentar por dz (1,50, 1,59, 1,64, 1,61) e por kg (2,09, 2,19, 2,24, 2,22), espessura de casca (0,387, 0,384, 0,386, 0,381mm), porcentagem de casca (9,44, 9,43, 9,37, 9,31%), unidade Haugh (92,50, 93,14, 91,34, 91,57) e gravidade específica (1,0856, 1,0851, 1,0850, 1,0839) não indicaram qualquer diferenças entre os tratamentos (P>0,05). A utilização do Bacillus subtilis como agente probiótico, quando utilizado a partir da recria, da postura ou durante as duas fases, não possibilita melhoras no desempenho e qualidade de ovos de poedeiras de 50 a 66 semanas de idade.

Desempenho e qualidade de ovos de poedeiras de 50 a 66 semanas de idade suplementadas com probiótico

The experiment was carried out to evaluate probiotic on laying hen performance and egg quality. The probiotic was fed from pullet phase and the effects were evaluate from 50 to 66 weeks. A completely randomized experimental design with four treatments (probiotic suplementation in pullet and laying phase, probiotic suplementation only in pullet phase, probiotic suplementation only in laying phase and no suplementation), and six replicates of eight birds each was used. The rations contained 15.50 and 17.00% crude protein and 2800 and 2750kcal metabolizable energy/kg respectively in pullet and laying phases. The results of feed intake (106.53, 110.81, 107.25, 109,72g), egg production (85.20, 83.66, 79.18, 81.94%), egg weight (59.84, 60.53, 61.11, 60.33g), alimentary conversion per dz (1.50, 1.59, 1.64, 1.61), and per kg (2.09, 2.19, 2.24, 2.22), shell thickness (0.387, 0.384, 0.386, 0.381mm), shell percent (9.44, 9.43, 9.37, 9.31%), Haugh unit (92.50, 93.14, 91.34, 91.57) and specific gravity (1.0856, 1.0851, 1.0850, 1.0839) did not indicate any treatment effect (P>0.05). The utilization of Bacillus subtilis as probiotic during pullet phase, laying phase or pullet and laying phases did not improve the performance and egg quality of laying hens from 50 to 66 weeks of age.

Objetivou-se, com este trabalho, avaliar o efeito de probiótico sobre o desempenho e qualidade de ovos de poedeiras. A suplementação de probiótico foi iniciada na fase de recria e os efeitos foram avaliados de 50 a 66 semanas. O delineamento experimental adotado foi inteiramente ao acaso com quatro tratamentos (suplementação de probiótico na fase de recria e postura, suplementação de probiótico somente na fase de recria, suplementação de probiótico somente na fase de postura e ausência de suplementação) e seis repetições de oito aves cada. Nas fases de recria e postura, as rações continham 15,50 e 17,00% de proteína bruta e 2800 e 2750kcal de energia metabolizável/kg. Os resultados de consumo de ração (106,53, 110,81, 107,25, 109,72g), produção de ovos (85,20, 83,66, 79,18, 81,94%), peso de ovos (59,84, 60,53, 61,11, 60,33g), conversão alimentar por dz (1,50, 1,59, 1,64, 1,61) e por kg (2,09, 2,19, 2,24, 2,22), espessura de casca (0,387, 0,384, 0,386, 0,381mm), porcentagem de casca (9,44, 9,43, 9,37, 9,31%), unidade Haugh (92,50, 93,14, 91,34, 91,57) e gravidade específica (1,0856, 1,0851, 1,0850, 1,0839) não indicaram qualquer diferenças entre os tratamentos (P>0,05). A utilização do Bacillus subtilis como agente probiótico, quando utilizado a partir da recria, da postura ou durante as duas fases, não possibilita melhoras no desempenho e qualidade de ovos de poedeiras de 50 a 66 semanas de idade.