Carlos Eduardo do Prado Saad

Comparação de métodos de avaliação dos valores energéticos do grão de trigo e seus subprodutos para frangos de corte

One experiment was run with broiler chickens to evaluate the metabolizable energy (ME), ((apparent (MEA), true (MEV), apparent corrected for nitrogen retention (MEAn) and true corrected for nitrogen retention (MEVn)). The traditional and the forced fed methods were compared in a factorial design 4×8 (methods×feedstuffs) with four replicates. Seven feed ingredients originating from wheat were used in five experiments: wheat grain, wheat germ, white wheat flour, dark wheat flour, wheat bran for human use, wheat bran for animal use and rough wheat bran. The first two methods were the traditional methodology with ad libitum feeding, using birds with different ages, 13 and 39 day-old, respectively. The feedstuffs tested substituted 40% of a reference diet. In methods three and four the birds were fasted 30 hours and forced fed 25g of the feed ingredients (Sibbald, 1976). In all the experiments a treatment was included with fasting birds, to determine metabolic and endogenous losses. In method four caecectomized birds were used. Feeds and excreta were analyzed for dry matter, protein and gross energy for determination of the metabolizable energy values. MEA and MEAn values were smaller when the birds were forced fed. Caecectomized birds showed the highest values of MEV. The feedstuffs MEVn values determined by the traditional method did not show statistical differences among the feeds, however some feed ingredients resulted in different values when compared with those determined with forced fed birds. The MEV/MEA and MEVn/MEAn relationships were narrowed in the methods with ad libitum feed consumption.

Equações de regressão para estimar valores energéticos do grão de trigo e seus subprodutos para frangos de corte, a partir de análises químicas

One experiment was run with broiler chickens, to obtain prediction equations for metabolizable energy (ME) based on feedstuffs chemical analyses, and determined ME of wheat grain and its by-products, using four different methodologies. Seven wheat grain by-products were used in five treatments: wheat grain, wheat germ, white wheat flour, dark wheat flour, wheat bran for human use, wheat bran for animal use and rough wheat bran. Based on chemical analyses of crude fiber (CF), ether extract (EE), crude protein (CP), ash (AS) and starch (ST) of the feeds and the determined values of apparent energy (MEA), true energy (MEV), apparent corrected energy (MEAn) and true energy corrected by nitrogen balance (MEVn) in five treatments, prediction equations were obtained using the stepwise procedure. CF showed the best relationship with metabolizable energy values, however, this variable alone was not enough for a good estimate of the energy values (R2 below 0.80). When EE and CP were included in the equations, R2 increased to 0.90 or higher in most estimates. When the equations were calculated with all treatments, the equation for MEA were less precise and R2 decreased. When ME data of the traditional or force-feeding methods were used separately, the precision of the equations increases (R2 higher than 0.85). For MEV and MEVn values, the best multiple linear equations included CF, EE and CP (R2>0.90), independently of using all experimental data or separating by methodology. The estimates of MEVn values showed high precision and the linear coefficients (a) of the equations were similar for all treatments or methodologies. Therefore, it explains the small influence of the different methodologies on this parameter. NDF was not a better predictor of ME than CF.

Avaliação do gasto e Consumo voluntário de rações balanceadas e semente de girassol para papagaios-verdadeiros (Amazona aestiva)

Utilizou-se de 12 papagaios adultos, distribuidos em blocos ao acaso em seis tratamentos (Racao extrusada para psitacideos, Racao peletizada para psitacideos, Racao comercial extrusada para psitacideos, Racao extrusada para caes linha premio; Racao extrusada para caes linha economica e Semente de Girassol), durante tres periodos de cinco dias de colheita, com 7 dias de adaptacao entre colheitas, totalizando seis repeticoes por tratamento, em que foram avaliados o gasto total (materia seca - MS e materia natural - MN) e o consumo total de MN, MS, proteina bruta (PB), energia metabolizavel aparente e verdadeira corrigidas pelo N (EMAn e EMVn), calcio (Ca) e fosforo (P), por ave e por quilograma de peso metabolico. As medias obtidas foram comparadas pelo teste SNK. Os resultados obtidos permitiram concluir que: 1- os consumos medios de MS foram influenciados negativamente pelo teor de energia metabolizavel da dieta; 2- o alto consumo das aves recebendo semente de girassol sugere que, alem da densidade energetica, a palatabilidade da dieta tem grande influencia no consumo voluntario; 3- todas as dietas testadas atenderam as necessidades diarias de proteina bruta; 4- o consumo de calcio da semente de girassol nao atendeu a necessidade diaria do elemento. 5- o tamanho do grânulo parece interferir no gasto e desperdicio de racao pelas aves.

Avaliação nutricional de rações comerciais e semente de girassol para papagaios-verdadeiros (Amazona aestiva)

Neste experimento utilizou-se de 12 papagaios adultos, distribuidos em blocos ao acaso em seis tratamentos (T1-Racao extrusada para psitacideos - A, T2 -Racao peletizada para psitacideos-B, T3 - Racao extrusada para psitacideos-C, T4 - Racao para caes linha premio; T5- Racao para caes linha economica e T6 - Semente de Girassol), durante tres periodos de colheita, totalizando seis repeticoes por tratamento. Avaliaram-se os valores de energia metabolizavel aparente e verdadeira (EMA e EMV) e corrigidas pelo nitrogenio (EMAn e EMVn); coeficientes de digestibilidade dos nutrientes (energia bruta - EB, materia seca - MS, materia orgânica -MO, fibra bruta-FB e extrato etereo - EE), balanco de nitrogenio e proteina metabolizavel das dietas testadas. As medias foram comparadas pelo teste SNK. Os resultados obtidos permitiram concluir que 1) os valores de EMA e EMV foram mais altos que EMAn e EMVn. 2) A semente de girassol apresentou a mais alta digestibilidade aparente e verdadeira da materia seca e da materia orgânica. 3) A digestibilidade dos lipideos de todas as dietas foi alta (media de 92,62%). 4) O balanco de nitrogenio (aparente e verdadeiro) foi positivo para todas as aves.

Avaliação dos coeficientes de digestibilidade dos aminoácidos do grão de trigo e seus subprodutos para frangos de corte utilizando diferentes metodologias

One experiment was run with broiler chickens to evaluate the coefficients of digestibility of amino acids (coefficients of apparent digestibility of amino acids - CDAaa and coefficients of true digestibility of amino acids - CDVaa) using wheat grain and some of its by-products, comparing four methodologies. The experiment was a completely randomized factorial design 4×8 (treatments × feedstuffs) with four replicates. Seven wheat grain by-products were used: wheat grain, wheat germ, white wheat flour, dark wheat flour, wheat bran for human use, wheat bran for animal use and rough wheat bran. Treatments 1 and 2 were the traditional methodology with ad libitum feed consumption, just differing in the age of the birds, 13 and 39 day-old, respectively. The feed tested substituted 40% of a reference diet. Feed intake and total excreta were recorded. The forced feeding method was used (Sibbald, 1976) for treatments 3 and 4. The birds were fasted 30 hours and forced fed 25g of the feed ingredients. In all the experiments a treatment was included with fasting birds to determine metabolic and endogenous losses. In method four caecectomized birds were used. Feeds and excreta were analyzed for dry matter, protein and amino acids. The traditional methods showed higher CDAaa values when compared to the forced feeding methods. For white wheat flour and dark wheat flour these values were negative, showing that endogenous losses were larger than amino acid intake. High fiber feedstuffs (wheat bran for human use , wheat bran for animal use and rough wheat bran) showed the lowest CDAaa and CDVaa values in the traditional and forced fed methods, confirming the interference of crude fiber on amino acid digestibility. In regard to the CDVaa, differences were smaller when compared the traditional and the forced fed methods, however, caecectomized birds showed lower CDAaa, due to high metabolic and endogenous losses.

Energia metabolizável de alimentos utilizados na formulação de rações para papagaios-verdadeiros (Amazona aestiva)

A total of 34 blue fronted parrot were allotted in blocks with 17 treatments (T1 - reference diet, T2 - sunflower seed, T3 - oat, T4 - egg yolk, T5 - integral egg, T6 - egg white, T7 - wheat germen, T8 - wheat bran, T9 triturated corn, T10 - jellied corn, T11 - sunflower bran, T12 - yeast, T13 - citric pulp, T14 - papaya, T15 - banana, T16 - soy bran, T17 extruded soy) during three periods, totaling six repetitions (102 experimental units). For feedstuffs evaluation by using a substitution methodology. Were determined the metabolizable coefficients of crude energy (apparent - CMAE, true - CMVE, apparent corrected by N - CMAnE and true corrected by N - CMVnE) and the values of metabolizable energy (apparent - EMA, true - EMV, apparent nitrogen corrected - EMAn and true nitrogen corrected - EMVn) of the tested feedstuffs. All feedstuffs were statistically analyzed. The metabolizable coefficients of EB were compared by the Scott-Knott test , while for the energetics feedstuffs values were analyzed as a descriptive analysis (means and standard deviation). The obtained results allowed to conclude that: 1 - the apparent metabolizable energy of the sunflower seed shown high value and the use of this feed as a only feed source should be used in medium period to avoid the obesity in the birds in maintenance state ; 2 - the energetic feeds as the triturated corn, wheat bran, wheat germen, soybean meal and extruded soy for parrots were similar the those found in the literature for domestic birds, mainly broiler chickens, suggesting that the extrapolation the digestibility energy data of domestic birds mainly broilers should be used for parrots ratios calculations , until that a feedstuffs table for psittacines is set up definitively.

Digestibilidade e retenção de nitrogênio de alimentos para papagaios verdadeiros (Amazona aestiva)

Foram utilizados 34 papagaios verdadeiros alojados em gaiolas metabolicas e distribuidos em blocos ao acaso em 17 tratamentos (T1 - racao referencia, T2 - semente de girassol, T3 - aveia, T4 - gema de ovo, T5 - ovo integral, T6 - clara de ovo, T7 - germe de trigo, T8 - farelo de trigo, T9 - milho moido, T10 - milho gelatinizado, T11- farelo de girassol, T12 - levedura, T13 - polpa citrica, T14 - mamao, T15 - banana, T16 - farelo de soja, T17 - soja micronizada), durante tres periodos de colheita, totalizando seis repeticoes (102 unidades experimentais). Para avaliacao dos alimentos utilizou-se a tecnica de substituicao. Foram avaliados os coeficientes de digestibilidade da materia seca (MS) e materia orgânica (MO) e a retencao de nitrogenio dos alimentos, comparando os tratamentos dois a 17, sendo que o delineamento experimental foi em blocos ao acaso, com 16 tratamentos, tres periodos experimentais e seis repeticoes. O tratamento um (racao referencia) foi utilizado apenas para os calculos de substituicao, nao fazendo parte das analises estatisticas. As medias foram comparadas pelo teste Scott-Knott. Os resultados obtidos permitiram concluir que: 1 - Os papagaios apresentaram alta digestibilidade da MS e MO para os alimentos: milho gelatinizado, gema de ovo, semente de girassol, aveia, ovo integral, milho moido, mamao e banana, podendo ser considerados como boas opcoes de escolha para a composicao de uma dieta completa; 2 - alimentos como a polpa citrica e o farelo de girassol apresentaram baixas digestibilidades aparente e verdadeira da MS e MO, e devem ser utilizados em niveis baixos e com moderacao na formulacao de racoes para estas aves; 3 - a retencao de nitrogenio verdadeiro foi positiva para todas as aves, sugerindo que ainda estejam em anabolismo, entretanto, devido ao alto coeficiente de variacao, esta medida parece nao ser adequada para expressar o coeficiente real de retencao de nitrogenio para papagaios.

Diet assessment in cockatiels reproduction and reproductive parameters

Cockatiels are monogamous birds that reach sexual maturity at twelve months, with posture ranging from three to seven eggs. They are classified as granivores, although some studies have shown a great diversity in eating habits. This work was performed in investigative character, in order to compare the effect of diet on reproduction of cockatiels and perform a survey of reproductive parameters of the species. The experiment was conducted at the Federal University of Lavras. Statistical analyzes were performed using the SAS GLM (Statistical Analysis System, Cary, NC, USA). The variable order posture showed significance (P<0.1) with the variables, shell thickness, egg weight and time of hatching. The variable egg weight showed significance (P<0.1) with the variables posture order and width of the egg. The results found in this study support the conclusion that the formulated diet was able to satisfy the nutritional needs of the calopsitas in the reproductive phase, not affecting the quality and the fertility of the eggs.

Food preferences of cockatiel chicks ( Nymphicus hollandicus ) in captivity

In order to improve the management and maintenance of the quality of life of captive wild birds, this study aimed to assess the food preferences of cockatiel chicks (Nymphicus hollandicus) kept in captivity. Thirty-two cockatiel chicks, three to 12 months of age, were kept in a galvanized, wire-netted vivarium with six ceramic feeders, two for an extruded diet, two for a dry-mashed diet and two for a seed mixture. Both extruded and drymashed food are commercial psittacine diets. Three round ceramic pots were used to provide water. The birds were exposed to 12 hours of artificial light (40 W incandescent lamps) during the experimental period of 27 days. The birds were observed by video filming, daily, through an ad libitum observation technique. The food consumption was 3.34±0.42g/bird/day of extruded feed, 1.58±0.44g/bird/day of dry-mashed diet and 3.73±0.10g/bird/day of seed mixture. In conclusion, the cockatiel chicks preferred the seed mixture and the extruded food over the dry-mashed diet.

Equações de predição dos valores energéticos dos alimentos para papagaios verdadeiros (Amazona aestiva)

The objective of this study was to predict the energetics values by using the data set from the metabolism assay and proximal analyses of 16 feeds (sunflower seed, oat, egg yolk, integral egg, egg white, wheat germen, wheat bran, triturated corn, jellied corn, sunflower bran, yeast, citric pulp, papaya, banana, soybean meal, extruded soybean). The prediction equations of the apparent metabolizable energy (AME), apparent nitrogen corrected (AMEn), true (TME) and true nitrogen corrected (TMEn) for blue fronted parrots (Amazon aestiva) adults in the maintenance. Based on the chemical analyses of 16 feeds and in the of metabolizable energy values (AME, TME, AMEn and TMEn) obtained from the assays with parrots, the prediction equations were determined. The parameters used for the calculations of the equations were Organic Matter (OM), Crude Protein (CP), Crude Energy (CE), Crude Fiber (CF), Ethereal Extract (EE), Ashes (As) and Free Nitrogen Extractive (FNE), analyzed in the feds. The equations to predict the metabolizable energy of the groups of feeds were determined through simple and multiple linear regressions, by using the method of stepwise of the SAS statistical package (SAS INSTITUTE, 1995). Accord to the equation it was concluded that : 1 - EE was the variable that was better correlated with the metabolizable energy (AME, AMEn, TME and TMEn) with high positive correlation; 2 - although many equations showed the R2 above 0,90, none of them was able to predict the metabolizable energy for all feeds evaluated, probably due to the heterogeneous nature of the nutrients in the feeds.