Características do trato digestivo, metabolizabilidade e retenção de nutrientes em frangos de corte alimentados com complexo enzimático / Characteristics of the digestive tract, metabolizability and nutrient retention in broilers fed enzymatic complex

The objective was to evaluate the digestive tract characteristics, metabolizability and nutrient retention of broilers fed diets supplemented with enzyme complex (EC). To evaluate the characteristics of the digestive tract 600 female Cobb 500 birds were used, distributed in a completely randomized design, with 5 inclusion levels of the EC (0; 100, 200, 300 and 400 g/ton) and 6 replicates of 20 birds each. To evaluate the metabolizability and the retention of nutrients 200 female Cobb 500 birds at 15 days of age were used, distributed in a completely randomized design with 5 levels of supplementation of the EC and 4 replicates of 10 birds each. No significant effects (P>0.05) were observed for the supplementation of the EC in the intestinal pH, digestive organ weight, intestinal length and metabolizable coefficients of dry matter and crude protein. The metabolizable coefficient of ethereal extract was influenced in a quadratic decreasing form (P<0.01). The metabolizable coefficients of calcium (Ca) and phosphorus (P) were influenced in a quadratic increase (P<0.01), resulting in increased Ca retention in 21.39% and P in 9.56%. Supplementation of the EC in broiler diets improves the metabolizability and retention of P and Ca, without affecting the other parameters evaluated.(AU)

Efficacy of carvacrol on Rhipicephalus (Boophilus) microplus engorged female ticks (Canestrini, 1887) (Acari: Ixodidae): effects on mortality and reproduction.

The activity of carvacrol was evaluated in R. microplus female ticks by estimating the mean lethal concentration (LC50) and the acaricidal efficacy. Ticks were subjected to the Adult Immersion Test (AIT) to calculate LC50. From this value, the AIT was performed again at the concentrations of 20%, 40%, 60%, 80% and 100% of the LC50. Two control groups were established: one treated with distilled water and one with the solvent (ethanol 50%). The following parameters were evaluated: female weight before oviposition, egg mass weight, pre-oviposition and incubation period, hatching percentage, egg production index, fecundity rate, estimated reproduction, reduction in oviposition and hatching, and product efficacy. The obtained LC50 was 20.11 mg/mL. Egg mass weight, egg production index, pre-oviposition and fecundity rates of groups treated with 80% and 100% of LC50 were statistically different when compared to control groups. The product efficacy in groups treated with 100% of LC50 was 61.10%.

Digestible methionine+cysteine in the diet of commercial layers and its influence on the performance, quality, and amino acid profile of eggs and economic evaluation.

This work aimed at evaluating the effects of 4 digestible Met+Cys levels on the diet of commercial layers and their influence on the productive performance, quality, and amino acid profile of eggs and economic viability of the activity. A total of 576 white Lohmann LSL-Lite layers was distributed into 6 replicates of 24 birds for each diet. The experimental design was completely randomized, with 4 treatments defined by levels evaluated in the feed (0.465, 0.540, 0.581, and 0.647%). The productive performance was measured for 30 weeks. The quality (34 and 50 wk old) and the amino acid profile of eggs (43 wk old) also were evaluated. A linear positive response was observed at higher Met+Cys levels for feed intake, number of eggs per housed bird, and digestible Met+Cys intake. Egg production, egg weight, egg mass, feed efficiency, and weight gain had their optimal values determined by the quadratic regression model at 0.638, 0.654, 0.647, 0.644, and 0.613% digestible Met+Cys, respectively. In the 34th wk, eggshell thickness decreased linearly at higher Met+Cys levels. In the 50th week, the optimal levels detected for eggshell thickness and percentage were 0.571 and 0.570% digestible Met+Cys, respectively. The percentages of proteins, branched-chain amino acids (leucine, isoleucine, and valine), histidine, and proline in eggs (albumen+yolk) showed a linear negative response in function of higher Met+Cys levels. Higher digestible Met+Cys levels (>0.630%) led to a good performance of layers, while lower Met+Cys levels improved the eggshell quality of layers in peak production. Optimal Met+Cys levels may change according to the price of the synthetic amino acid.

Avaliação da suplementação antioxidante na dieta para galos de matrizes pesadas em idade avançada sobre parâmetros reprodutivos / Evaluation of antioxidant supplementation in diet for aging broiler breeder roosters on reproductive parameters

Objetivou-se avaliar os efeitos de antioxidantes suplementados às dietas de galos de matrizes pesadas em idade avançada sobre as características reprodutivas. Foram utilizados galos da linhagem Cobb com 47 semanas de idade. Estes foram distribuídos em quatros tratamentos, de acordo com a adição de antioxidante à dieta, sendo: A = grupo controle (sem suplementação antioxidante); B = suplementação de 9ppm de citranaxantina; C = suplementação de 6ppm de cantaxantina e D = 150ppm de vitamina E. Foram avaliadas as características seminais, tais como volume, vigor, motilidade e concentração, a composição de ácidos graxos do sêmen (saturados, insaturados, monoinsaturados, poli-insaturados, ômega 3, ômega 6 e ômega 9) e a correlação entre o peso dos testículos e o peso dos galos. Não foram observados efeitos das substâncias antioxidantes testadas sobre os parâmetros reprodutivos avaliados. Os antioxidantes avaliados não influenciam as respostas reprodutivas de machos reprodutores de matrizes pesadas em idade avançada.(AU)

This study aimed to evaluate the effect of antioxidant supplementation in diets of aging broiler breeder roosters on reproductive characteristics. Cobb roosters were divided into four groups, according to antioxidant addition, where: A = control group (without antioxidant supplementation); B = 9ppm of citranaxanthin; C = 6ppm of canthaxanthin, and D = 150ppm of vitamin E. Seminal characteristics (volume, force, motility and concentration), semen fatty acid composition (saturated, unsaturated, monounsaturated, polyunsaturated, ω3, ω6 and ω9), and the correlation between testis weight with rooster weight were evaluated. No effects of the antioxidants tested were observed. The antioxidants do not influence the reproductive responses of aging male broiler breeder.(AU)

Desempenho de frangos de corte alimentados com diferentes níveis de suplementação de vitamina E / Effect of vitamin E supplementation on the performance of broiler chickens

Objetivou-se a avaliação dos efeitos dos níveis de suplementação de vitamina E na ração para frangos de corte sobre o desempenho na fase inicial (um a 21 dias de idade) e de crescimento (21 a 39 dias de idade). Os tratamentos foram definidos pelos níveis de suplementação de vitamina E (DL-α tocoferol). As quantidades adicionadas às rações foram: 10; 30; 50; 75 e 100mg de vitamina E para cada kg de ração. Na fase inicial (experimento I), o menor nível de suplementação de vitamina E mostrou-se superior aos demais, apresentando efeito significativo (P≤0,05) sobre o peso médio aos 21 dias de idade e ganho de peso de um a 21 dias de idade. Na fase de crescimento (experimento II), não houve efeito significativo (P>0,05) dos níveis de suplementação de vitamina E sobre as variáveis estudadas. O nível mínimo de suplementação de vitamina E testado (10mg/kg) é suficiente para atender às exigências dos frangos de corte machos sobre o desempenho.(AU)

This study aimed to evaluate the effect of vitamin E supplementation on the performance of broiler chickens in the initial and growth phase, from one to 21 and 21 to 39 days of age, respectively. Five increasing levels of DL-α tocopherol supplementation (10, 30, 50, 75 and 100mg to each kg of diet) were added to the diet. In the initial phase (experiment I), the lowest vitamin E level was superior by presenting significant effect (P≤0.05) on body weight at 21 days of age and weight gain from one to 21 days old. In the growth phase (experiment II), there was no significant effect (P>0.05) of vitamin E supplementation on the variables studied. The minimum level of vitamin E supplementation tested is sufficient to attend the requirements of male broiler chickens.(AU)

Suplementação de colina em dietas para frangos de corte machos em fase de crescimento / Choline supplementation in diets for male broilers in the growing phase

Avaliaram-se os efeitos dos níveis de suplementação de colina em dietas para frangos de corte, de 22 a 40 dias de idade, sobre o desempenho, a composição de carcaças e fígados, bem como as características macroscópicas e histopatológicas dos fígados. O período de criação foi de um a 40 dias de idade, sendo que o período experimental foi de 22 a 40 dias de idade. Até o 21º dia de idade, todas as aves receberam a mesma ração à qual foram adicionados 400mg colina/kg. No 22º dia, os frangos foram distribuídos em cinco tratamentos, nos quais os níveis testados de suplementação de colina foram: zero, 400, 800, 1.200 e 1.600mg/kg, com seis repetições de 30 aves cada. As rações experimentais, formuladas à base de milho, farelo de soja e farinha de carne/ossos, foram isonutritivas, com exceção dos níveis de colina. O delineamento experimental foi o inteiramente ao acaso, e a estimativa da suplementação de colina foi avaliada pelos modelos de regressão. Os níveis de suplementação de colina apresentaram efeito linear pelo teste F (P<0,05) para o consumo de ração. Os demais parâmetros avaliados não sofreram influência da suplementação (P>0,05). O nível de 1.600mg colina/kg de ração resulta em maior consumo de ração de frangos de corte aos 40 dias de idade.

The effects of choline supplemental levels were evaluated in diets for broilers on performance, carcass and liver composition and liver histopathology characteristics from 22 to 40 days-old. The period of creation was one to 40 days of age, and the experimental period was 22 to 40 days-old. Until 21 days of age all birds received the same diet added to 400mg choline/kg. On day 22, broilers were allotted to five treatments (zero, 400, 800, 1200 and 1600 mg/kg), with six repetitions of 30 birds each. The experimental diets formulated based on corn, soybean meal and meat/bones meal were isonutritive, except for the choline levels. The experimental design was completely randomized and the estimation of choline supplementation was evaluated by regression models. The levels of choline supplementation showed a significant linear effect for the F test (P<0.05) for feed intake. The other evaluated parameters were not influenced by supplementation (P>0.05). The supplementation of 1600mg choline/kg in the diet results in higher feed intake of broilers at 40 days old.

Efeitos da suplementação de colina sobre o desempenho de poedeiras comerciais / The effects of choline supplementation on the performance of laying hens

Os efeitos da suplementação de colina em dietas para poedeiras (Dekalb White) foram avaliados nas fases de cria/recria e de postura. O delineamento foi em esquema fatorial 2x5 (duas suplementações de colina de uma a 16 semanas de idade x cinco níveis de colina suplementada de 18 a 44 semanas de idade). Os níveis de colina utilizados foram 0, 200, 400, 600 e 800mg/kg para cada grupo. A suplementação de colina em frangas com uma a 16 semanas de idade não afeta o desempenho nem as características macroscópicas e histopatológicas dos fígados durante essa fase. Os efeitos dos níveis de suplementação de colina sobre o desempenho das galinhas na fase de postura dependem da suplementação ou não dessa vitamina nas fases de cria/recria; ou seja, as aves que recebem suplemento de colina nessas fases apresentam maior exigência no período de postura.

The effects of choline supplementation in diets for laying hens (Dekalb White) were evaluated from 1 to 44 weeks-old. The experimental design was a 2x5 factorial arrangement (two choline supplementations from one to 16 weeks of age - with and without choline supplementation vs. five levels of choline supplementation from 18 to 44 weeks old. The choline level used in the diet for each group was 0, 200, 400, 600 and 800mg/kg). Choline supplementation used in birds with 1 to 16 weeks of age does not affect the performance of pullets and no gross and histological changes were observed in the liver during this phase. The effects of the choline supplementation levels in the laying phase on the hens' performance depend on the supplementation with this vitamin from 1 to 16 weeks old. The results of the experiment showed that birds reared for laying need a higher level of choline supplementation from 1 to 16 weeks old or birds reared for laying receiving higher levels of choline supplementation during 1 to 16 weeks old will need a higher level of choline supplementation in the laying phase.

Suplementação de colina em dietas para frangos de corte machos na fase inicial de criação / Levels of supplementation of choline in diets for male broilers in initial phase

Foram avaliados os efeitos da suplementação de colina em dietas para frangos de corte sobre o desempenho produtivo e a composição da carcaça e do fígado e sobre as características macroscópicas e histopatólogicas do fígado na fase inicial de criação. Os tratamentos foram definidos pela suplementação de colina - zero, 100, 200, 300 e 400mg de colina/kg de ração, durante o período de criação de um a 21 dias de idade. As dietas experimentais, formuladas à base de milho, farelo de soja e farinha de carne, foram isonutritivas, com exceção dos níveis de colina. O delineamento experimental utilizado foi o inteiramente ao acaso, e a estimativa da suplementação de colina foi avaliada pelos modelos de regressão. A suplementação de colina apresentou efeito linear significativo para conversão alimentar, e as demais características avaliadas não foram influenciadas pela suplementação. A suplementação de 400mg colina/kg de ração melhora a conversão alimentar de frangos de corte aos 21 dias de idade.

The effects of supplemental levels of choline on performance, carcass composition and gross and histopatology characteristics of the livers in the initial phase in diets for broiler chickens were evaluated. The treatments were defined by the levels of choline supplementation (zero, 100, 200, 300 and 400mg choline/kg diet). The period of creation was one to 21 days-old. Diets formulated based on corn, soybean meal and meat meal are constituted by isonutrient except the levels of choline. The experimental design was completely randomized and the estimation of choline supplementation was evaluated by regression models. The levels of choline supplementation showed a significant linear effect for the F test (P<0.05). Values for feed and other parameters were not influenced by supplementation (P>0.05). The supplementation of 400 mg choline/kg diet improves feed conversion of broilers at 21 days old.

Effects of lipid sources in the diet of laying hens on the fatty acid profiles of egg yolks.

The effects of different dietary lipids on the fatty acid profiles of eggs produced by 20- and 54-wk-old Dekalb laying hens were investigated. The 4 treatments were based on the lipid source added to the diet: soybean oil, sunflower oil, linseed oil, or control (no added oil). The experimental design was a simple random-sample design using a 4 × 2 factorial arrangement (4 treatments and 2 ages). The fatty acid composition of the yolks of eggs produced by the laying hens was analyzed. The fatty acid profiles found in the egg yolks were the same as those provided in each diet. Eggs laid by hens fed the diet containing soybean oil had a large amount of n-6 polyunsaturated fatty acids (PUFA), whereas eggs laid by hens fed the diet containing linseed oil had the highest percentage of n-3 PUFA. A decrease in PUFA deposition in egg yolks was observed as the laying hens got older. Eggs of hens fed the diet containing linseed oil presented an n-6:n-3 ratio of 2.01 in younger chickens and 2.17 in older ones. The trans fat percentages found in the egg yolks of all treatments were very low. It was concluded that the quantity of fatty acids present in the egg yolk may be altered according to the source of lipids in the diets; the addition of linseed oil to the ration of laying hens resulted in the production of n-3-enriched eggs and excellent n-6:n-3 ratios, and the egg yolks had insignificant amounts of trans fat, irrespective of the different lipid sources added to the diets or the age of the chickens.

Fontes de lipídios na dieta de poedeiras: desempenho produtivo e qualidade dos ovos / Lipids sources on layer hen diet: performance and egg quality

Os efeitos de fontes de lipídios na dieta de poedeiras sobre o desempenho produtivo e a qualidade do ovo foram verificados em dois experimentos. Foram utilizados quatro tratamentos, definidos de acordo com a fonte lipídica adicionada nas rações: óleo de soja, óleo de girassol, óleo de linhaça e ração controle (sem adição de óleo). Os experimentos foram realizados com poedeiras de 20 e 54 semanas de idade, respectivamente, com duração de oito semanas. Avaliaram-se os parâmetros produtivos - consumo de ração, conversão alimentar, produção e peso dos ovos - e de qualidade do ovo - porcentagens de gema, albúmen e casca, sólidos da gema, unidades Haugh, pH do albúmen, e cor da gema. Somente o peso do ovo de poedeiras jovens foi afetado pela inclusão de óleos vegetais na ração. Esses ovos apresentaram maior peso e maior porcentagem de gema que os produzidos pelas poedeiras jovens alimentadas com ração-controle. Concluiu-se que a utilização de diferentes fontes de lipídios na ração de poedeiras não altera o desempenho produtivo e a qualidade interna dos ovos, com exceção do peso do ovo de poedeiras novas, que aumenta com a utilização de óleos vegetais.

The effects of different sources of fat in the diet of layer hens on performance and egg quality were recorded in two experiments. Four treatments were defined by the lipid source added to the diets: soybean oil, sunflower oil, linseed oil and control diet (without oil added). The experiments were carried out with layers from 20 to 54 weeks of age, respectively, for eight weeks. Production parameters (feed intake, feed conversion, egg production, and egg weight) and quality of eggs (percentages of yolk, albumen, and shell; total solids of yolk; Haugh units; pH of albumen; and yolk color) were evaluated. Among the parameters of production and quality of the eggs, only the weight of eggs and percentage of yolk of young hens were affected by the inclusion of vegetable oils in the diet. These eggs were significantly heavier and had higher percentage when compared with the eggs of hens fed the control diet. It was concluded that the utilization of different sources of oils in layers diet did not change performance and egg quality , except egg weigh of young layers, that increased with the utilization of vegetables oils.

Efeitos dos programas de luz sobre desempenho, rendimento de carcaça e resposta imunológica em frangos de corte / Effect of lighting programs on performance, carcass yield, and immunological response of broiler chickens

Avaliaram-se os efeitos dos programas de luz 23L:1E (23L); crescente (CRES); 16L:8E (16L) e luz natural (NAT) sobre o desempenho, rendimento de carcaça e resposta imunológica de frangos de corte machos da linhagem Cobb-500. O período de criação foi de um a 45 dias de idade, e os tratamentos foram definidos de acordo com os programas de luz. O delineamento experimental foi o inteiramente ao acaso com quatro tratamentos e seis repetições de 35 aves cada. As aves submetidas ao programa de luz CRES apresentaram maior peso vivo em relação aos demais tratamentos (P<0,05). O consumo de ração também foi maior para as aves do tratamento CRES quando comparado aos tratamentos 23L e NAT (P<0,05), e semelhante ao tratamento 16L (P>0,05). A viabilidade das aves do tratamento NAT foi maior em relação às aves do tratamento 23L (P<0,05) e semelhante aos demais tratamentos (P>0,05). A conversão alimentar e o rendimento de carcaça não foram influenciados pelos tratamentos (P>0,05). As aves do tratamento 23L apresentaram maior rendimento de peito quando comparado aos demais tratamentos (P<0,05). A produção de anticorpos para a doença de Newcastle não foi afetada pelos tratamentos (P>0,05).

The effects of lighting programs 23L:1E (23L); increasing (INC); 16L: 8E (16L) and natural light (NAT) on performance, carcass yield and immune response of Cobb-500 male broiler were evaluated. Chicks were raised from one to 45-day-old and the treatments were defined according to the lighting programs. The experiment was designed in four treatments with six repetitions of 35 birds each. Broilers of the INC lighting program showed heavier weights (P<0.05). Feed consumption was higher in broilers of the INC treatment when compared to the 23L and NAT (P<0.05), and similar to the 16L (P>0.05). The viability of the NAT treatment broilers was higher than the broilers of the 23L (P<0.05) and similar to the other treatments. Feed conversion and carcass yield were not influence by the treatments (P>0.05). The 23L treatment broilers showed higher breast yield when compared to the other treatments (P<0.05). Differences were not observed among the treatments regarding antibodies levels against Newcastle disease (P>0.05).

Efeito do período de jejum pré-abate sobre o rendimento de carcaça de frango de corte / Effect of pre-laughter fasting periods on the carcass yielding of commercial broilers

Avaliaram-se os efeitos de cinco períodos (quatro, oito, 12, 14 e 16 horas) de jejum pré-abate sobre a perda de peso e rendimento de carcaça e cortes de frangos de corte. Foram utilizados 240 frangos (120 machos e 120 fêmeas), linhagem Cobb, criados até 44 dias de idade. No 44° dia, as aves foram separadas de acordo com o período de jejum (tratamentos) e o sexo, cada tratamento com 24 repetições. Nos tratamentos de quatro, oito, 12 e 16 horas, o jejum foi alimentar e no tratamento de 14 horas, o jejum foi alimentar e hídrico. O teste utilizado para as análises das médias foi o SNK (Student-Newman-Keuls). Foram analisadas as seguintes variáveis: perda de peso vivo após o jejum, taxa de absorção de água pela carcaça, rendimentos da carcaça inteira e dos cortes comerciais coxa e sobrecoxa, peito, dorso, asa, pés e cabeça e pescoço, rendimentos da moela e fígado e peso dos intestinos. Os períodos de jejum de oito, 12, 14, e 16 horas apresentaram maior rendimento de carcaça, sendo superiores ao período de quatro horas de jejum (P<0,05). O tratamento de quatro horas de jejum apresentou maior rendimento de fígado e peso de intestino em relação aos demais tratamentos (P<0,05). O período de jejum não influenciou a taxa de absorção de água nem o peso de moela (P>0,05). As fêmeas absorveram mais água do que os machos, e apresentaram rendimentos de carcaça e cortes comerciais superiores aos dos machos (P<0,05).

This experiment was designed in order to evaluate the effect of five intervals of pre-slaughter fasting (four, eight, 12, 14 and 16 hours) on weight loss, carcass yielding and poultry cuts yielding of broiler chickens. A total of 120 males and 120 females broiler chickens of Cobb lineage were raised during 44 days. On the 44th day, chickens were grouped according to their fasting period (treatments) and gender. Each treatment was composed of 24 repetitions. Animals of the of four, eight, 12 and 16 hours treatments were not fed ration while animals of the 14 hours fasting treatment were not fed ration or water. The statistical test used for mean comparison was SNK (Student-Newman-Keuls). The following variables were analyzed: loss of live weight, rate of water absorbed by carcass; whole carcass and commercial cuts (legs and forelegs, chest, dorsum, wings, feet and head and neck) yielding; gizzard and liver yielding as well as intestinal weight. The fasting periods of eight 12, 14 and 16 hours showed greater carcass yielding (P<0.05) being higher than those from the four hours fasting period. The four hours fasting group showed the highest yielding of liver and intestinal weight in relation to the other groups (P<0.05). The fasting period did not influence the rate of water absorption or the gizzard weight (P>0.05). Females retained more water than males and showed higher carcass and commercial cuts yielding than males (P<0.05).

Efeito de fontes lipídicas sobre o desempenho de frangos de corte / Effect of lipid sources of diets on broiler performance

Avaliou-se O efeito de fontes lipídicas (óleo degomado de soja, óleo de vísceras de aves, óleo ácido de soja, mistura de 50% de óleo de soja e 50% de óleo de vísceras e mistura de 50% de óleo de soja e 50% de óleo ácido de soja) adicionadas às rações sobre o desempenho de frangos de corte, machos, da linhagem Ross. Os tratamentos foram definidos de acordo com a fonte de lipídio, e o período de criação foi de 1 a 45 dias de idade. As rações, para cada fase de criação, foram isonutritivas. O delineamento experimental foi o inteiramente ao acaso, com cinco tratamentos e seis repetições com 30 aves cada. As aves que receberam óleo de soja ganharam mais peso quando comparadas com as que receberam óleo ácido de soja (P<0,05). O consumo de ração das aves alimentadas com óleo de soja foi maior em relação ao das alimentadas com rações contendo óleo ácido de soja e mistura de óleo de soja com óleo ácido de soja. Quanto à conversão alimentar e à viabilidade, não foram observadas diferenças significativas entre os tratamentos (P>0,05). A utilização do óleo de soja nas rações melhorou o desempenho de frangos de corte quando comparado com o uso do óleo ácido de soja.