Débora Cristine de Oliveira Carvalho

Uso de prebióticos à base de mananoligossacarídeo em rações para frangos de corte

O experimento foi realizado com objetivo de estudar o uso de mananoligossacarideos (standard e concentrado) em racoes para frangos de corte. Foram utilizados 1.080 pintos de corte machos da marca Ross, com peso medio inicial de 42 g, distribuidos em um delineamento inteiramente ao acaso, com seis tratamentos e nove repeticoes de 20 aves por unidade experimental. As aves foram criadas em cama de maravalha reaproveitada, utilizada anteriormente por outro lote. Foram testados os tratamentos: testemunha, antibiotico (avilamicina), mananoligossacarideo alta concentracao (MOS AT), mananoligossacarideo standard (MOS ST), MOS AT + avilamicina e MOS ST + avilamicina para avaliacao do ganho de peso, do consumo de racao, da conversao alimentar, da viabilidade e do rendimento de cortes. No periodo de 1 a 21 dias de idade, nao foram encontradas diferencas significativas entre os tratamentos para as variaveis consumo de racao, conversao alimentar e viabilidade economica. Os resultados de desempenho das aves alimentadas com racao contendo MOS ST ou MOS AT, combinados ou nao com o antibiotico, nao diferiram dos obtidos nos tratamentos com avilamicina e da racao basal. No periodo de 1 a 42 dias de idade, a adicao de MOS ST, combinado ou nao com avilamicina, melhorou o ganho de peso das aves, enquanto o MOS AT afetou de forma negativa o ganho de peso. A conversao alimentar, o consumo de racao e a viabilidade economica nao foram influenciados pelos tratamentos. No entanto, o uso de aditivos em racoes para frango de corte melhorou o rendimento de cortes e reduziu a gordura abdominal.

Adição de complexo multienzimático em dietas à base de soja extrusada e desempenho de pintos de corte

One experiment was conducted to evaluate the effect of the addition of multienzymatic complex in diets with different quality of extruded full fat soybeans on the performance of broiler chicks. A total of 960 Avian Farms male broiler chicks were used from 1 to 21 days of age. The completely randomized experimental design utilized a 3 x 2 factorial treatment structure with three extruded full fat soybeans (under, standard and over processed) and two levels of multienzymatic complex addition (0.0 and 0.05%). Total of six treatments and eight replicates of 20 birds for experimental unit. The diets were formulated to contain corn end extruded full fat soybeans, with crude protein, lysine and methionine+cystine below recommended levels to facilitate detection of nutritional differences. The solubility values in KOH 0.2% and urease of the different extruded full fat soybeans they were respectively: under processed (91% and 0.5), standard (88% and 0.05) and over processed (66% and 0.005%). The multienzymatic complex was composed with celulase, amylase and protease. The birds and ration were weighted in the initial and final experimental phase to get weigh gain, feed intake and feed conversion. The addition of multienzymatic complex in diets contend extruded soybean with different processing improved weight gain in 3.8% and the feed conversion in 4.24%. The largest effect of addition was observed with birds fed under processed soybean, where weight gain and feed conversion improved by 4.64 and 5.0% respectively. Birds fed diets with standard extruded soybean, showed better performance when compared with birds fed with extruded soybean, under and over processed.

Níveis nutricionais de cálcio e de fósforo disponível para aves de reposição leves e semipesadas de 13 a 20 semanas de idade

Four experiments were accomplished using 720 white-egg pullets and 720 brown-egg pullets from 0 to 6 age weeks, were allotted to a completely randomized design with five calcium levels (.70, .80, .90, 1.00, and 1.10%) or five levels of available phosphorus (.30, .35, .40, .45, and .50%), with four replicates and 18 pullets for experimental unit. The experimental diets were formulated with soybean meal and corn to contain 2900 kcal of metabolizable energy/kg of diet, 18% crude protein, .70% calcium for calcium experiments and .30% of available phosphorus for phosphorus experiments. Diets and water were ad libitum fed during the experimental period. The evaluated characteristics were weight gain, feed intake, feed: gain ratio, bone resistance, bone ash and bone calcium (calcium experiments) or bone phosphorus (experiments of available phosphorus). Requirements of .937% and .961% of calcium and .420% and .423% of available phosphorus for white-egg pullets and brown-egg pullets, respectively, were estimated.

Exigência de arginina digestível para frangos de corte machos em diferentes fases

Three experiments were conducted to determine the arginine requirement and the digestible arginine:lysine ratio of broiler males, from 1 to 20, 24 to 38 and 44 to 56 days of age. A completely randomized design with five levels of arginine, six replicates and 20 birds per pens from 1 to 20 and 24 to 38, and 16 birds per pens from 44 to 56 were used in each experiment. The concentrations of digestible arginine were 1.10-1.34 (increase of 0,061), 1.083-1.296 (increase of 0,053) and 0,96-1,148% (increase of 0,047) for 1-20, 24-38 and 44-56 days of age respectively. At the end of each experiment performance and carcass yield were evaluated. Body weight gain and feed conversion responded quadratically to increasing levels of digestible arginine in the first phase. Using the broken line model, the requirement of digestible arginine and the ratio of digestible arginine:lysine for the first phase were 1,22% (1,31% total) and 105%, respectively, according to the results of body weight gain. No statistical difference in the second and third phases (24-38 days old and 44-56 days old, respectively) showed that the lowest level of digestible arginine of 1,083% (1,155% total) and 0,960% (1,026) met the birds requirement. These levels corresponded to a ratio of 102% in both phases.

Fontes e níveis de metionina em dietas para frangos de corte

The objective of this study was to evaluate the effect of two sources of methionine, DL-Methionine (DLM - 99%) and Methionine Hydroxy Analogue Free Acid (MHA-FA - 88%), at three different levels of supplementation of this amino acids in commercial diets on the performance of broiler chickens. A total of 1.232 commercial Ross broilers was used, from 01 to 47 days of age, and allotted to a complete randomized design in a 2 X 3 factorial (source methionine X supplementation level) arrangement and a additional diet (basal) without supplementation, with eight replications of 22 birds per experimental unit. The basal diet was supplemented with 50, 100 and 150% of MHA-FA or DL-methionine in equivalent amount of 65% of the amount of MHA-FA used. Feed intake, weight gain, feed:gain ratio and production factor were determined. Within each supplementation level there were no significant differences between the diets containing 100 parts of MHA-FA and 65 parts of DL-methionine, except for the period of 01-10 days when there was significant difference for the weight gain at the lowest level of supplementation. In conclusion, 65 parts of DL-methionine is equivalent to 100 parts of MHA-FA.

Bioavailability of methionine sources for laying hens in the production period, in a high temperature environment

Objetivou-se determinar se a biodisponibilidade de metionina analoga acido livre (MHA-AL) e igual ou superior a 65%, na base de produto, para poedeiras leves no periodo de 24 a 40 semanas de idade. Durante quatro periodos experimentais de 28 dias, utilizaram-se 640 poedeiras comerciais com 24 semanas de idade, em um delineamento inteiramente casualizado, com dez tratamentos, oito repeticoes e oito aves por unidade experimental. Os tratamentos consistiram de uma racao basal farelada deficiente em metionina, contendo 2.830 kcal de energia metabolizavel (EM)/kg, 14,5% de proteina bruta (PB) e 0,23% e 0,21% de metionina total e digestivel, respectivamente, suplementada com DL-metionina 99%, DLM (0,0325; 0,05; 0,065; 0,0975; 0,10 ou 0,15%) e com MHA-AL 88% (0,05; 0,10 e 0,15%). As caracteristicas avaliadas foram peso corporal (kg), producao de ovos (%), massa de ovos (g), peso medio dos ovos (g), consumo de racao (g) e conversao alimentar (g de racao/g de ovo). Com base nos dados de producao de ovos, massa de ovo e conversao alimentar, a biodisponibilidade da MHA-AL foi calculada em 74,66; 73,97; e 71,17%, respectivamente, conferindo a MHA-AL biodisponibilidade media de 73,22% em relacao a DLM, na base do produto. A biodisponibilidade da MHA-AL e superior a 65% na base do produto.The objective of the study was to determine whether bioavailability of methionine hydroxy analogue free acid (MHA-FA) is higher than 65%, in product basis, for 24 to 40 week-old laying hens. Six hundred and forty 24-week commercial laying hens were used in four 28-day experimental periods in a randomized complete design with ten treatments, eight replications and eight birds per experimental unit. The treatments were based on a basal feed deficient in methionine, containing 2,830 kcal metabolizable energy (EM)/kg and 14.5% crude protein (CP), with 0.23% and 0.21% total and digestible methionine, respectively, supplemented with DL-methionine 99% DLM (0.0325; 0.05; 0.065; 0.0975; 0.10 and 0.15%) and MHA-FA (0.05; 0.10 and 0.15%). The following variables were assessed: body weight (kg), egg production (%), egg mass (g), egg weight (g), feed intake (g), feed conversion (g/feed/egg). Based on the egg production evaluation, egg mass and feed conversion, the bioavailability of MHA-FA was estimated at 74.66, 73.97 and 71.17%, respectively, giving MHA-FA an average bioavailability of 73.22% compared to DLM on product basis. The MHF-FA bioavailability was higher than 65% on product basis.

Nutritional levels of calcium and available phosphorus for white-egg pullets and brown-egg pullets from 0 to 6 weeks of age

Four experiments were carried out using white-egg pullets and brown-egg pullets in two different phases, growth phase (7 to 12 age weeks) and production phase (20 to 28 age weeks), with objective to determine requirements of calcium and available phosphorus and the effects of levels calcium e available phosphorus in production. Chickens from 13 to 19 weeks age were identified for treatment and fed only commercial diet. For each experiment, the chickens were allotted in a completely randomized design with five calcium levels (0.60, 0.70, 0.80, 0.90, and 1.00%) or five level available phosphorus (0.25, 0.30, 0.35, 0.40, and 0.45%), four replicates and 16 pullets/EU for the growth phase and 8 chickens/EU for the production phase. The characteristics evaluated for the growth phase were weight gain, feed intake, feed: gain ratio, bone resistance, ash and bone calcium (calcium experiments) or bone phosphorus (experiments phosphorus), while for the egg production phase were evaluated ration consumption, eggs production, egg weight, egg mass and feed conversion (g ration/g egg and kg of ration/dozen of egg). Calcium requirements of 0.834% or 406 mg/pullets/day for white egg pullets and 0.815% or 440 mg/pullets/day for brown eggs pullets were estimated and for available phosphorus, requirements of 0.411% or 200 mg/pullets/day for white egg pullets and 0.361% or 184 mg/pullets/day for brown eggs pullets were estimated.

Exigência de treonina para pintos de corte no período de 1 a 21 dias de idade

This experiment was carried out to determine the threonine requirement for broilers chicks from 1 to 21 days of age and to evaluate the effect of different threonine levels on the uric acid excretion in broilers. One thousand and two hundred broiler chicks were randomly allotted to a 6x2 factorial arrangement, being six levels of total threonine (.73, .77, .81, .85, .89, and .93%) and two sexes, with five replicates of 20 birds each. Feed intake, weight gain, feed:gain ratio and plasma uric acid levels were evaluated. A biologic trial using the total collection of feces method was conducted to evaluate the effect of threonine level on the uric acid excretion. There were linear positive and negative effects of the threonine levels on males and females weight gain, respectively, and quadratic effect on feed intake and feed:gain ratio of males and female. The threonine levels did not influence the uric acid plasmatic levels in the birds, and was not observed effect of threonine levels on the uric acid excretion. The levels of .86% and .73% of total threonine and .73% and .62% of digestible threonine were sufficient to maximize performance of males and females, respectively.

Crude protein level of pre-starter diets and nutritive solution for broilers

The objective of the present study was to evaluate the effect of dietary crude protein (CP) levels and the use of a nutritive solution via drinking water on the performance of pre-starter broilers. A total of 1,224 male Avian Farm chicks, from one to 40 days of age were used. Birds were distributed in a completely randomized experimental design with a 3 × 2 × 2 factorial arrangement, consisting of three initial body weights (low: 41 g, standard: 45 g and high: 49 g; two crude protein levels at the pre-starter phase (22 and 25% CP),with or without the addition of a nutritive solution, whose nutritional level was similar to the 25% CP pre-starter diet, at a concentration of 5% of the drinking water. Each treatment included six replicates and 17 chicks per experimental unit. At the end of the pre-starter phase, all hens received a diet with 22% CP until day 21 and a diet with 20% CP from the 21st to the 40th day. The use of the pre-starter diet with higher nutritional levels and the nutritive solution enhanced broiler performance. The early nutrient supply via drinking water resulted in better broiler performance and uniformity. However, birds with low initial body weight continued to present lower body weight at market age.

Lysine nutritional requirements of broilers reared in clean and dirty environments during the pre-starter and starter phases

A total of 3,760 Ross male broiler chicks were used in two trials, one in the pre-starter (1-11 days) phase and the other in the starter (12-22 days) phase. Birds were distributed in a completely randomized experimental design with a factorial arrangement of 5 digestible lysine levels × 2 environments (clean and dirty environment), with eight replicates per treatment. The following dietary digestible lysine levels used were: 1.06, 1.12, 1.18, 1.24 and 1.30% in the pre-starter phase, and 1.00, 1.06, 1.12, 1.18 and 1.24% in the starter phase. Minimal relation of digestible lysine:digestible methionine + cystine, threonine, tryptophan and arginine (72, 67, 19 and 108%, respectively) were maintained, as well as 2.088 and 2.002% of glycine+serine in the pre-starter and starter diets, respectively. Weight gain, feed intake and feed conversion were evaluated. In all phases, dietary digestible lysine levels significantly influenced broiler performance, and broilers reared in the clean environment presented better performance than those reared in the dirty environment. The recommended digestible lysine levels during the pre-starter and starter phases are 1.30 and 1.24% when broilers are reared in the clean enviroment and 1.26 and 1.165% in the dirty enviroment, respectively.