Jerônimo Ávito Gonçalves de Brito

Níveis de cálcio e granulometrias do calcário para frangas e seus efeitos sobre a produção e qualidade de ovos

Realizou-se um experimento com o objetivo de avaliar os efeitos dos niveis nutricionais de calcio e das granulometrias do calcario em racoes para frangas nas fases de cria e recria sobre a producao de ovos. Utilizaram-se 600 poedeiras da linhagem Lohmann LSL, alimentadas nos periodos de cria e recria com racoes experimentais suplementadas com fitase (500 FTU/kg) e calcario em granulometrias fina (DGM = 0,135 mm) e grossa (DGM = 0,899 mm) para atender os niveis de 0,60; 0,75; 0,90; 1,05 e 1,20% de Ca total na racao. Os tratamentos foram dispostos em esquema fatorial 2 x 5, com cinco repeticoes e 12 aves por unidade experimental e quatro periodos de 21 dias. Na fase de postura (18 a 30 semanas de idade), as aves receberam a mesma racao com 3,60% de Ca. O nivel de 0,60% de Ca e as granulometrias do calcario fornecido nas fases de cria e recria foram suficientes para proporcionar bom desempenho na postura e nao afetaram a qualidade externa e interna dos ovos no periodo estudado.

Efeitos da suplementação enzimática e da forma física da ração sobre o desempenho e as características de carcaça de frangos de corte

A study was conducted in order to verify the effect of enzyme supplementation (EndopowerbO, based on de a-galactosidase, galactomanase, xilanase e b-glucanase) and feeding different physical forms of diets on performance and carcass yield of broilers from 1 to 42 dais old. A total of 1488 broilers chickens, 8 treatments, 6 replicates and 31 broilers per experimental unit plot were fed with diets based on corn and soybean, with enzyme supplementation 200 or 400g for ton. and without enzymes supplementation and two physical forms (meal and pelleted ). Two additional basal diets with the energetic values of corn and soybean meal valued in 2 and 9% respectively and digestibilidade of amino acids digestibility valued in 4% by using one treatment with no enzyme supplementation and another one with enzyme supplementation of 200g/ton. Two periods 1-21 and 22-42 days old were evaluated. Reduced feed intake were observed in linear way (P 0.05) on the broiler performance from 1 to 21 days old.

Efeito da vitamina D3 e 25-hidroxi-colecalciferol sobre o desempenho, o rendimento de carcaça e a morfologia intestinal de frangos de corte¹

O experimento foi conduzido com o objetivo de avaliar niveis de suplementacao de vitamina D proveniente de duas fontes (D3 e 25-OHD3) em racoes para frangos de corte criados em gaiolas. Foram utilizados 1.500 pintos machos de 1 dia, linhagem Cobb-700, alojados em gaiolas metalicas (100) com dispositivos e manejo adaptados para criacao das aves. Em cada fase do desenvolvimento (inicial, de 1 a 21 dias; de crescimento, 22 a 38 dias; e final, de 39 a 45 dias), avaliaram-se quatro niveis (programas) de suplementacao de vitamina D (20/16/10; 37,5/30/18,8; 87,5/70/43,8 e 137,5/110/68,8 mg/kg racao), oriunda de duas fontes. Os dois tratamentos adicionais foram constituidos da combinacao das duas fontes (D3 + 25-OHD3), em diferentes proporcoes (50+37,7/40+30/25+18,8 e 50+70/40+56/25+35 mg/kg de racao para as fases inicial, crescimento e final, respectivamente). O delineamento experimental foi inteiramente casualizado, em esquema fatorial 2 × 4 + 2 (fontes × niveis + adicionais) e 10 repeticoes por tratamento As racoes foram a base de milho e farelo de soja, com suplementacao de fitase (500 ftu/kg), segundo recomendacoes das tabelas brasileiras de exigencias nutricionais de animais nao-ruminantes. Foram avaliados o desempenho, o rendimento de carcaca e a morfologia intestinal das aves. A suplementacao de vitamina D na fase inicial melhorou o ganho de peso e a conversao alimentar das aves. Maior ganho de peso e consumo de racao aos 45 dias foi observado nas aves dos tratamentos adicionais (associacoes). O rendimento de carcaca aumentou com o uso de 25-OHD3. Em comparacao a suplementacao isolada das fontes de vitamina D, os tratamentos adicionais promoveram maiores beneficios para a maioria das caracteristicas avaliadas. A adicao de 25-OHD3 em racoes contendo vitamina D3 melhora as caracteristicas de desempenho dos frangos de corte.

Níveis de cálcio e granulometrias do calcário para frangas de reposição no período de 3 a 12 semanas de idade

The effects of feeding different calcium levels and limestone particle sizes on body and morphometric development of the digestive tract in replacement pullets were evaluated in this trial. One thousand and four hundred Lohmann LSL replacement pullets were assigned to a complete randomized design with a 5 x 2 factorial (calcium levels and limestone particle size) and five replicates of 28 and 18 birds/plot, respectively, for the periods from 3 to 7 and from 8 to 12 weeks old. The experimental diets contained: corn, soybean meal and wheat meal (wheat only at growing phase) and were formulated to be isonitrogenous, isoenergetic and isophosphorus (monoammonium phosphorus). Diets were supplemented with minerals, vitamins and phytase (500 FTU/Kg) and added with limestone in fine (DGM = 0.135 mm) and gross (DGM=0.899 mm) particle sizes to meet the levels of 0.60, 0.75, 0.90, 1.05 and 1.20% of dietary total calcium. The performance in the period from 3 to 12 weeks, morphometry of the digestive tract and contents of tibia ashes and minerals in animals slaughtered at 12th week old were evaluated. The feed intake increased linearly as the dietary calcium levels increased. No significant differences on weight gain, feed conversion, percentage of digestory tract and metatarsus length were noticed. Better tibia ash content were observed with 0.60% of calcium and a longer length of the small intestine in pullets fed diet with gross particle size of limestone. The diet with calcium level of 0.60% and gross particle size of limestone resulted in better esqueletic development, worse feed intake and larger length of small intestine.

Uso de microminerais sob a forma de complexo orgânico em rações para frangas de reposição no período de 7 a 12 semanas de idade

This experiment was carried out to study the effects of feeding trace minerals as organic complex on the performance and bone characteristics for pullets in the period from 7-12 weeks old. The treatments consisted of the supplementation of trace minerals in the inorganic form (control) and organic form with inclusion of 0.4% in the diet, that corresponds to the supplement levels of 60, 80, 70, 10, 1, and 0.3 ppm of zinc, iron, manganese, copper, iodine and selenium, respectively, and the decreasing dietary levels of organic source (0.35, 0.3, 0.25, and 0.2%). A total of 648 Lohmann - LSL pullets from the 7th week old were allotted to a completely randomized design with six treatments and six replicates of 18 birds. No significant treatment effect on performance characteristics and uniformity up to the 12th week was observed. There was a linear reduction of ash porcentage in the tibia of pullets in the 12th week as the dietary organic supplement decreased. However there were no significant differences among the inorganic source (control) and the other treatments (organic source). The zinc content in the tibia as well as the weight, length and thickness of tibia and femur and metatarsus length were not affected by the treatments, in the 12th week. The trace mineral organic source showed relative comparative advantage and resulted in 0.2% reduction of the dietary supplement level of organic source with no effect on the performance and bone characteristics of pullets from 7 to12 weeks old.

Evaluation of cysteamine associated with different energy patterns in diets for broiler chickens

This experiment was conducted with the objective of evaluating cysteamine (CS) supplementation in broiler chick diets with different energy density patterns. A total of 980 chicks of the Cobb 500 strain at one day of age were allocated into 28 plots. A completely randomized design in a 2 × 2 factorial arrangement, with 7 replications, was adopted. The factors under study were the supplementation (or absence) of cysteamine (60 mg/kg and 80 mg/kg of feed in the starter and growth/finishing phases, respectively) and two patterns of apparent metabolizable energy corrected by nitrogen balance (AMEn) in the diets. The energy levels (Mcal/kg of feed) practiced in pattern 1 were 3.00; 3.10; and 3.20, and for pattern 2, they were 3.05; 3.20; and 3.30 in the starter, growth and finishing phases, respectively. The diets were on the basis of corn and soybean meal with a feeding program with three diets. Feed intake, weight gain, feed conversion, feasibility and carcass yield were evaluated. There was no interaction between the CS supplementation and AME patterns in the diet upon the performance and/or carcass characteristic evaluated. Broilers fed the diet supplemented with CS presented improved feed conversion along the rearing cycle, but feed intake and weight gain were not affected by the supplementation of CS. The highest pattern of energy density (2) provided increased weigh gain in the starter phase of rearing and better feed conversion of the birds over the whole rearing period. The carcass yield was not influenced by the cysteamine supplementation and/or energy levels studied.

Calcium levels and particle size of limestone for replacement pullets the period of 3 to 16 weeks of age

The present work had the objective of to evaluate the effects of the nutritional levels of calcium and particle sizes of limestone replacement pullet rations on the performance and morphometric development of the digestive tract. A total of 1.400 replacement pullets of the Lohmann LSL strain, by using the CRD design in a 5 x 2 factorial scheme (calcium levels and particle size of limestone) with five replicates with 28 pullets per plot for the period of 3 to 5 weeks of age. The experimental diets were based on corn and soybean meal supplemented with minerals, vitamins and phytase (500 FTU/Kg). The rations were formulated to be a isoprotein, isocaloric and isophosphorus, being the phosphorus source supplied by monoammonium phosphorus and balanced according to the Lohmann (1999) strain Handbook, supplemented with limestone in fine (DGM = 0.135 mm) and gross (DGM = 0.899 mm) particle size to meet the levels of 0.60, 0.75, 0.90, 1.05 and 1.20% of total calcium in the diet. The performance in the period of 3 to 5 weeks, morphometry of the digestive tract and contents of ash and minerals in the pullet tibia of each plot were taken after slaughtered pullet on the 5th week old. Feed conversion shown interaction to calcium levels and particle size of limenstone, occurring quadract effect of calcium levels in the gross particle size, with better feed conversion in the level of 0,96% of Ca. Inside of level 0,90% Ca the gross particle size shown better feed conversion. The pullets fed rations with limestone particle size of 0,899 mm had minus length of small intestine (cm/kg) and percentage of digestory tract. The better level of ash in the tíbia was obtained with the calcium level of 0,93% Ca. The gross particle size provided a higher level of P in tibia and any differences on levels of calcium levels were observed.

Níveis de cálcio e granulometrias do calcário para frangas de reposição no período de 3 a 5 semanas de idade

Realizou-se este experimento com o objetivo de avaliar os efeitos dos niveis nutricionais de calcio e granulometrias do calcario em racoes de frangas de reposicao sobre o desenvolvimento corporal e morfometrico do trato digestorio. Foram utilizadas 1400 frangas de reposicao da linhagem Lohmann LSL, empregando-se um DIC em esquema fatorial 5x2 (niveis de calcio e granulometrias do calcario), com 5 repeticoes e 28 aves por parcela, no periodo de 3 a 5 semanas de idade. As dietas experimentais foram a base de milho e farelo de soja suplementada com minerais, vitaminas e fitase (500 FTU/kg), sendo isonutrientes, tendo como fonte de fosforo o fosfato monoamonio e balanceadas de acordo com o Manual da linhagem (LOHMANN, 1999). Utilizou-se o calcario em granulometrias fina (DGM = 0,135 mm) e grossa (DGM = 0,899 mm) para atender os niveis de 0,60; 0,75; 0,90; 1,05 e 1,20% de calcio total na dieta. Avaliaram-se o desempenho no periodo de 3 a 5 semanas, a morfometria do trato digestorio e os teores de cinzas e minerais na tibia de aves de cada parcela abatida na 5a semana de idade. Nao houve diferencas significativas no ganho de peso, consumo de racao e comprimento do metatarso. A conversao alimentar apresentou interacao para niveis de calcio e granulometria do calcario, sendo observado efeito quadratico dos niveis de calcio dentro da granulometria grossa, com melhor conversao observada no nivel de 0,96% de Ca. Dentro do nivel 0,90% de Ca, a granulometria grossa apresentou melhor conversao. As aves que receberam a granulometria de 0,899 mm do calcario apresentaram menor comprimento do intestino delgado (cm/kg PV) e porcentagem de trato digestorio. Obteve-se efeito quadratico dos niveis de calcio sobre o teor de cinzas na tibia, sendo o teor maximo de cinzas observado no nivel de 0,93% de Ca. A granulometria grossa do calcario proporcionou tambem um maior teor de fosforo na tibia, nao observando diferencas sobre os teores de calcio.

Nutrient reduction in rations with phytase for growing pigs

Two experiments were conducted to evaluate the performance, the energy and nutrient balance and economic viability of production of growing pigs fed diets with reduced levels and phytase. In experiment 1, 60 barrows and gilts (initial weight 25 ± 1.72 kg) were housed in a randomized block design with three diets, ten replicates and two animals per experimental unit (one male and one female). One of the diets was formulated with a reduced level with phytase and evaluated in comparison to a positive-control diet that was formulated according to the nutritional recommendations for animals of this breed, and a negative-control diet without phytase. The different diets did not affect feed intake, but the diet with phytase promoted better final weight, daily weight gain and feed conversion, although it did not differ from the positive control diet. In experiment 2, 27 barrows (initial weight 49 ± 3.67 kg) were housed in random blocks with three diets and nine replicates with experimental plot represented by one animal. The diets did not affect the balance of energy and nutrients but had a significant effect on the efficiency of utilization of calcium and phosphorus, which was the lowest in animals that received the positive-control diet. Economic viability improved when nutrients were reduced and phytase was added in the ration. The addition of phytase (500 ftu/kg) in rations formulated with nutritional levels reduced for growing swines improves rearing productivity and it is economical viable.