Valdir Silveira de Avila

Substituição de farinhas de origem animal por ingredientes de origem vegetal em dietas para frangos de corte

The demand of some importers due to cultural reasons or to zoonosis that recently emerged in Europe, there has been a trend to manufacture vegetable feeds based on corn and soybean meal (SBM). This influences live production, and therefore, this study aimed at evaluating the response of broilers fed diets containing either meat and bone meal (MBM) and offal meal (OM), or vegetable diets based on corn and SBM. Diets were calculated to supply 3050 and 3150 kcal ME/kg for the starter and grower phase, respectively, as well as to supply the requirements for all the other nutrients. The following treatments were tested: 1. Diet with inclusion of 4% swine MBM and 3% OM, calculated on Ideal Protein basis, containing 22% and 20% CP in the starter and grower phase, respectively; 2. Diet similar to 1, with no inclusion of animal meals, based on corn and SBM (similar CP and Digestible Lysine as to diet 1); 3. Diet similar to 2, but with 23% and 21% CP (Digestible Lysine similar to diet 1); Diet similar to 2, but with 24% and 22% CP (Digestible Lysine 6% and 5% higher than in diet 1). Dry matter content of the litter of birds fed exclusively vegetable ingredients and higher protein levels significantly deceased (P 0.05), but the feet weight was higher (P<0.01) in birds with lower dry matter content in the litter

Produção e qualidade de ovos em reprodutoras de frangos de corte com horário de arraçoamento diferenciado

Four feeding schedule were investigated for broiler breeders: at 6:30 am; 50% feeding at 6:30 am and 50% at 3:30 pm (dual); at 11:00 am, and at 3:30 pm. Arbor Acres breeders were randomly assigned to 48 boxes, with 12 replicates of 27 females and three males each. The nutritional levels and management procedures were those recommended for strain. The variables studied were: total egg production, nest, clean and broken egg production, in six collections (6:30 am, 9:00 am, 11:00 am, 1:30 pm, 3:30 pm and 5:30 pm); egg weight and egg specific gravity, grouped in three collections (9:00 am, 1:30 pm and 5:30 pm). Analysis of variance was used. Means were compared using Student t test for traits and collection and polynomial regression analysis for age. The collection and feeding schedule effects were significant for all traits, except for broken eggs, in which feeding schedule was not significant. The maximum egg production was obtained at 9:00 am for feeding schedule at 6:30 am (22.78 ± 0.36%) and dual (20.26 ± 0.33%), and at 1:30 pm for feeding schedule at 11:00 am (20.35 ± 0.39%) and at 3:30 pm (19.25 ± 0.38%). Female broiler breeders under the dual and at 3:30 pm feeding schedule showed egg weight of 71.0 ± 0.3 g, which was at least equal to the other feeding schedule in any collection. The egg specific gravity for feeding schedule at 11:00 am (1.0788 ± 2) and 3:30 pm (1.0799 ± 2) were higher than the other feeding schedule. Eggs from older female broiler breeders and eggs collected in the first hours of the day were heavier and had thinner eggshell than those from younger females and eggs collected later in the day. The dual feeding schedule could be an alternative to feeding schedule at 6:30.

Uso da metodologia de coleta total de excretas na determinação da energia metabolizável em rações para frangos de corte ajustadas ou não quanto aos níveis de vitaminas e minerais

The objective of this study was to evaluate the effects of vitamin and micromineral levels adjustment in the test diet on the total collection method for determination of apparent metabolizable energy (EMA) and apparent metabolizable energy corrected by nitrogen retention (EMAn) of soybean meal. Two treatments were compared: the test diet without or with adjustments in the amounts of choline chloride and vitamin-micromineral premix, when 40% of the reference diet was replaced with soybean meal. The traditional total feces collection method was used, with 360 Ross broilers from 15 to 23 days old. The chickens were allotted to batteries as a randomized block design, with two treatments and 12 ten-birds replicates (five males and five females). Mean values and respective standard errors for EMA and EMAn (kcal/kg) of soybean meal, as-fed basis, were of 2,462±29.62 and 2,269±25.80 for the adjusted diet and 2,353±26.18 and 2,191±23.88 for the diet without vitamin and micromineral adjustment. Adjustments of the amounts of choline choride and vitamin-micromineral premix in the test diet led to higher EMA and EMAn compared to the control test diet with no adjustments. Therefore, vitamin and micromineral levels in the test diet should be adjusted to the reference diet in experiments determining the metabolizable energy of feedstuffs used in poultry diets.

Determinação do período de coleta total de excretas para estimativa dos valores de energia metabolizável em frangos de corte

The effects of total excreta collection period length on estimated values of metabolizable energy [apparent (AME) and nitrogen corrected (AMEn)] were evaluated in broiler chickens from 19 to 23 days of age. Five treatments with six replicates were used in a randomized block design, in a total of 300 broiler chicks for the control and 300 broiler chicks for the reference diet. The control replaced 40% of reference diet with corn. After diet adaptation (four days), total excreta collection was performed during 1, 2, 3, 4 or 5 days, that consisted the treatments. Data were submitted to ANOVA using the GLM procedure of SAS (2001), with subsequent multiple mean comparison using Tukey test. Observed mean values of metabolizable energy for corn, as-fed basis, for the collection periods (1, 2, 3, 4 or 5 days) with the respective coefficients of variation (%), for AME (kcal/kg) were: 3,814 (7.26), 3,511 (5.32), 3,563 (2.51), 3,512 (1.31), and 3,489 (1.00) and for AMEn (kcal/kg) were: 3,709 (6.68), 3,434 (4.85), 3,482 (2.31), 3,438 (1.11), and 3,423 (1.03), respectively. It was concluded that a 4-d collection period is recommended to compose corn ME data with the same confidence as those of 5-d collection period.

Chemical and energy composition of corn harvested with various moisture levels and different drying temperatures to broiler chickens

The experiment was conducted to evaluate the effects of moisture levels at harvest and drying temperatures of corn on its chemical composition and apparent metabolizable energy corrected to zero nitrogen retention (AMEn) to broiler chickens. The corn was harvested with 35%, 25%, 18%, 15.3% and 14.3% of moisture and submitted to drying temperatures of 100, 70 and 40 oC. The moisture levels of 15.3% and 14.3% of corn were not submitted to drying and the last value represented the treatment post-harvesting (60 days after the first harvest). The chemical composition was determined by AOAC (1995) and AMEn assay was carried out by total collection procedure as described by Hill and Anderson (1958) and methodology of Matterson et al. (1965). When the AMEn values were considered on as fed basis, significant differences occured between the treatment of corn no drying and the others. The mean AMEn value was 11.8% less in energy (2864kcal/kg) relative to the highest value (3247kcal/kg).This is due to grain humidity having reached 24% on that treatment caused by natural grain natural re-hydration. When the energy values of corn were changed to dry-matter basis, there were no differences among the treatments. There were no major changes in nutritive value of corn harvested with different moisture levels and submitted to various drying temperatures, compared to expected standards, except the AMEn value (as fed basis) when the corn was no drying.

Influência do estádio de maturação na colheita e temperatura de secagem de grãos de trigo sobre os valores de energia metabolizável aparente corrigida (EMAc) em frangos de corte

An experiment was performed to evaluate the chemical composition values and Apparent Metabolizable Energy corrected for nitrogen excretion (AMEn) of wheat grain harvested at different maturity stage (13, 16, 20 and 30% of humidity levels) and drying temperatures (40, 70 and 100 oC). The grain with 13% of humidity level was considered dried at harvest and was not submitted to drying. The level of 16% of grain humidity at harvesting and the drying temperature of 40 oC provided the highest AMEn wheat value (3326 kcal/kg, as fed basis). Harvesting humidity and drying temperature affected the nutritional value of wheat. It is necessary to know the best maturity stage at harvest and drying temperatures of wheat grains regarding the variability on its nutritive value and inclusion into poultry diets.

Coccidiosis and performance in broilers with anticoccidial medicated feed starting at different ages

Estudou-se o efeito da idade das aves, da reutilizacao da cama vegetal e de programas anticoccidianos na coccidiose e desempenho de frangos. Utilizaram-se quatro lotes de 24 pintos cada (um dia de idade) submetidos a quatro tratamentos (T): T1 - aves nao tratadas com anticoccidiano, T2 - aves medicadas com anticoccidiano a partir do 14o dia de vida, T3 - aves medicadas com anticoccidiano a partir do setimo dia de vida, T4 - aves medicadas com anticoccidiano a partir do primeiro dia de vida. As contagens de oocistos aumentaram com a reutilizacao da cama, no terceiro lote. T1 (sem anticoccidiano) e T4 (anticoccidiano desde o primeiro dia) apresentaram as maiores contagens. Os escores por Eimeria acervulina aumentaram no terceiro lote e baixaram no quarto lote. Os escores por E. maxima aumentaram no segundo lote, e deste para o terceiro e quarto lotes. Os escores por E. tenella aumentaram no terceiro e quarto lotes. Com desafio alto, como ocorrido no terceiro lote, as medicacoes anticoccidianas a partir do primeiro, setimo e 14o dias resultaram em desempenhos semelhantes. Com desafios baixos ou moderados, como ocorridos nos lotes 1, 2 e 4, a medicacao a partir do 14o dia resultou em melhores desempenhos. Isso sugere que, em condicoes de baixo desafio, como em frangos criados em cama de primeiro uso e em granjas com aves de uma unica idade, a medicacao anticoccidiana a partir de 14 dias pode ser vantajosa em relacao aos programas de medicacao a partir do primeiro dia.