RESUMO

This study aimed to evaluate different n6:n3ratios on performance, serum biochemical variables, and egg quality in 81-week-old laying hens. A total of 224 laying hens, 81-week-old Hysex White, were utilized and distributed in a completely randomized design consisting of seven treatments and eight replications of four birds per cage, totaling 56 cages. The experimental treatments consisted of seven different n6:n3fatty acid ratios: 1.0:1.0, 2.0:1.0, 4.0:1.0, 8.0:1.0, 16.0:1.0, 32.0:1.0, and 64.0:1.0. For diet formulation, sunflower oil, rich in omega-6, and linseed oil, rich in omega-3, were used. Productive performance, egg quality and serum biochemical variables of laying hens were evaluated at the end of the cycle at 26, 27, and 28 days. Analysis of variance (ANOVA) was conducted and orthogonal contrasts were used to obtain the sum of squares of the treatment of the analysis of variance in polynomial regression effects. Egg quality variables did not vary significantly between the diets. Therefore, diet supplementation with polyunsaturated fatty acids at different ratios was possible without altering egg quality. The only exception was Haugh unit, which displayed a quadratic effect indicating that the best value was the n6:n3ratio of 32, according to data significance. It was concluded that an increase in n6:n3ratios decreases laying hens' feed intake. The n6:n3 ratio of 34.64 provides greater eggs' Haugh units, decreasing from that value on. The ratios of n6:n3 did not influence the hens' serum biochemical variables.(AU)

Assuntos

RESUMO

1. The effect of microencapsulated and uncoated butyric acid as an alternative to antibiotics on performance, intestinal morphology and regeneration of intestinal mucosa was studied in birds experimentally infected with Eimeria spp. 1 to 42 d-old.2. A total of 1,320 male Cobb® broiler chicks were allocated to one of five treatments in a completely randomised design, comprising a negative control, uncoated butyric acid (UA), microencapsulated butyric acid (MA), combined U + M butyric acid and a positive control (antibiotic+anticoccidial) in six replications. At 16 d-old, the birds were inoculated orally with 0.5 ml of a solution containing an Eimeria spp. pool.3. At 21 d of age, the birds receiving butyric acid alone had higher body weight gain (BWG) and feed intake (FI) compared to those supplemented with the blend of acids. For the total rearing period, in all variables, the positive control performed best (P < 0.001).4. At 14 d of age, birds that received diets containing UA had a deeper crypt depth in the jejunum than those fed diets containing microencapsulated acid (P = 0.0194). At 21 d of age, the birds fed the acids had higher villi (P = 0.0058) in the duodenum, compared to the negative control group.5. Supplementation with microencapsulated acid contributed to the intestinal health and recovery of post-challenge birds, but did not result in improvements in performance.

Assuntos

RESUMO

1. The effect of A. subrufescens and P. ostreatus mushrooms as an alternative to antibiotics (avilamycin or monensin sodium) on performance, intestinal morphometry, immunity, and biochemical profile of broilers challenged with Eimeria spp. was studied from 1 to 42 d old. A total of 900 male Cobb® broiler chicks were distributed, according to a completely randomised design, into five treatments with six replicates each.2. The treatments consisted of: negative control (NC) - basal diet (BD) with no anticoccidial or antibiotic (non-challenged birds); negative control challenged (NCC) - NC fed to Eimeria spp. challenged birds; BD with 0.2% A. subrufescens inclusion for challenged birds (As), BD with 0.2% P. ostreatus inclusion for challenged birds (Po); and a positive control - BD with anticoccidial and antibiotic inclusion for challenged birds (ATB).3. At 11 d.o., the birds were each inoculated orally with 1 ml solution containing 2 × 105 sporulated oocysts/ml Eimeria acervulina and 2 × 104 sporulated oocysts/ml E. maxima and E. tenella.4. Birds subjected to Eimeria spp. challenge up to 21 d of age had greater crypt depth, indicating that the presence of undesirable microorganisms had an effect on cell proliferation.5. At 21 d old, the birds receiving ATB had higher average weight gain (AWG), feed intake (AFI), and feed conversion ratio (FCR) compared to those fed diets supplemented with mushrooms (As or Po). For the total rearing period (42 days), the birds that received ATB had higher AWG and AFI (P < 0.001) compared to those that received As or Po diets. Feeding avilamycin did not affect (P = 0.0676) FCR compared to the As or Po diet groups.6. From the morphometric and blood analyses there were no differences between broilers fed ATB, Po or As diets in either rearing periods. However, Po and As supplementation lowered blood triglyceride levels. At 21d there was a difference (P < 0.05) for MCV and haemoglobin, in which the mushrooms were similar to the antibiotic. At 42 d, there was a difference (P < 0.05) in haematocrit, erythrocyte, MCV, H: L, protein and albumin variables, in which the use of mushrooms was similar to the positive control, demonstrating that both (mushrooms and antibiotics) promoted a certain improvement in the health of the chickens.7. A. subrufescens and P. ostreatus can be used in broiler diets without compromising intestinal or haematological status, however, these ingredients did not result in improvements in performance.

Assuntos

RESUMO

This study aimed to evaluate the effect of isolated or combined citric and benzoic acids added to the diets of broiler chickens on performance, allometry of the digestive system organs, intestinal pH and quantity of microorganisms in the jejunum. A total of 840 male Cobb broiler chicks were utilized, distributed in a complete random design in 2 × 2 factorial scheme, supplemented or not with citric acid, and sodium benzoate, with seven replications. At 14 days old, 1mL of a solution containing 1 × 105 sporulated oocysts of Eimeria acervulina per bird was inoculated orally. There was no effect of the acids on the broiler's performance in the 1 to 21-day period. In the total period (1 to 42 days), the broilers fed with a blend of citric and benzoic acid presented greater feed intake, without increment in weight gain. The data of allometry of the digestive system organs and the jejunal pH values were not influenced by the treatments. The citric acid increased the bacterial quantity of gram-positive coccus and total anaerobes in the jejunum. Under the conditions of the present study, we conclude that the citric and benzoic acids, isolated or combined, do not benefit the nutrition of broilers challenged with E. acervulina.(AU)

O objetivo deste trabalho foi avaliar os efeitos da inclusão isolada ou associada dos ácidos cítrico e benzoico na alimentação de frangos de corte sobre o desempenho, a alometria de órgãos do sistema digestório, o pH intestinal e a quantidade de microrganismos no jejuno. Foram utilizados 840 pintos de corte, machos, da linhagem Cobb, distribuídos num delineamento inteiramente ao acaso, em esquema fatorial 2 × 2, com suplementação ou não de ácido cítrico e suplementação ou não de benzoato de sódio, com sete repetições. Aos 14 dias de idade, foi inoculado, via oral, 1mL de solução contendo 1 × 105 oocistos esporulados de Eimeria acervulina por ave. Não houve efeito dos ácidos sobre o desempenho dos frangos no período de um a 21 dias. No período total (um a 42 dias), os frangos alimentados com a mistura de ácidos cítrico e benzoico apresentaram maior consumo de ração, sem incremento no ganho de peso. Os dados de alometria dos órgãos do sistema digestório e os valores de pH do jejuno não foram influenciados pelos tratamentos. O ácido cítrico aumentou a quantidade de bactérias do gênero cocos Gram positivos e anaeróbios totais no jejuno. Nas condições do presente estudo, conclui-se que os ácidos cítrico e benzoico, isolados ou associados, não beneficiam a nutrição de frangos de corte desafiados com E. acervulina.(AU)

Assuntos

RESUMO

This study aimed to evaluate the effect of isolated or combined citric and benzoic acids added to the diets of broiler chickens on performance, allometry of the digestive system organs, intestinal pH and quantity of microorganisms in the jejunum. A total of 840 male Cobb broiler chicks were utilized, distributed in a complete random design in 2 × 2 factorial scheme, supplemented or not with citric acid, and sodium benzoate, with seven replications. At 14 days old, 1mL of a solution containing 1 × 105 sporulated oocysts of Eimeria acervulina per bird was inoculated orally. There was no effect of the acids on the broiler's performance in the 1 to 21-day period. In the total period (1 to 42 days), the broilers fed with a blend of citric and benzoic acid presented greater feed intake, without increment in weight gain. The data of allometry of the digestive system organs and the jejunal pH values were not influenced by the treatments. The citric acid increased the bacterial quantity of gram-positive coccus and total anaerobes in the jejunum. Under the conditions of the present study, we conclude that the citric and benzoic acids, isolated or combined, do not benefit the nutrition of broilers challenged with E. acervulina.(AU)

O objetivo deste trabalho foi avaliar os efeitos da inclusão isolada ou associada dos ácidos cítrico e benzoico na alimentação de frangos de corte sobre o desempenho, a alometria de órgãos do sistema digestório, o pH intestinal e a quantidade de microrganismos no jejuno. Foram utilizados 840 pintos de corte, machos, da linhagem Cobb, distribuídos num delineamento inteiramente ao acaso, em esquema fatorial 2 × 2, com suplementação ou não de ácido cítrico e suplementação ou não de benzoato de sódio, com sete repetições. Aos 14 dias de idade, foi inoculado, via oral, 1mL de solução contendo 1 × 105 oocistos esporulados de Eimeria acervulina por ave. Não houve efeito dos ácidos sobre o desempenho dos frangos no período de um a 21 dias. No período total (um a 42 dias), os frangos alimentados com a mistura de ácidos cítrico e benzoico apresentaram maior consumo de ração, sem incremento no ganho de peso. Os dados de alometria dos órgãos do sistema digestório e os valores de pH do jejuno não foram influenciados pelos tratamentos. O ácido cítrico aumentou a quantidade de bactérias do gênero cocos Gram positivos e anaeróbios totais no jejuno. Nas condições do presente estudo, conclui-se que os ácidos cítrico e benzoico, isolados ou associados, não beneficiam a nutrição de frangos de corte desafiados com E. acervulina.(AU)

Assuntos

RESUMO

The effect of organic acids as an alternative to antibiotics on the performance of broiler chickens was evaluated by meta-analysis, identifying and quantifying the main factors that influence results. A total of 51,960 broilers from 121 articles published between 1991 and 2016 were used. Interactions of additives [non-supplemented group (control), organic acids, and growth promoter antibiotics] with microbial challenge (with or without inoculation of pathogenic microorganisms) were studied on performance variables. Moreover, the effects of organic acids, used individually or in blends, were evaluated. Relative values of average daily gain (ADG) and average daily feed intake (ADFI) were obtained in relation to control: ΔADG and ΔADFI, respectively. Analysis of variance-covariance revealed lower ADG with organic acids when compared to antibiotics (P < 0.05). There was a significant interaction between the additives and the challenge on feed conversion ratio (FCR) (P < 0.01) and on viability (P < 0.05). Without challenge, organic acids improved broilers' FCR (P < 0.01), presenting results similar to antibiotics (P > 0.05). Under challenge, the organic acids were again effective on FCR (-5.67% in relation to control, P < 0.05), but they did not match antibiotics (-13.40% in relation to control, P < 0.01). Viability was improved only under challenge conditions, and only by antibiotics (+4.39% in relation to control, P < 0.05). ADG (P < 0.05) and FCR (P < 0.01) were increased by blends of organic acids, but not by the organic acids used alone (P > 0.05). ADFI and production factor were not influenced by the treatments (P > 0.05). ΔADFI of organic-acid supplemented group showed a linear influence on ΔADG, which increases 0.64% at every 1% increase in ΔADFI. In conclusion, organic acids can be utilized as performance enhancing, but the results are lower than those found with antibiotics, particularly under microbial challenge. The blends of organic acids provide better results than the utilization of one organic acid alone.

Assuntos

RESUMO

Three experiments with a 2 × 2 × 2 factorial arrangement were conducted to evaluate maize-based diets for broilers containing different lipid sources [soybean oil (S) or beef tallow (T)] supplemented with or without lysophospholipids and organic acids on nutrient balance (Experiment I, evaluation period of 10-14 d), on liver concentration of fat-soluble vitamins, on jejunal microbiota (Experiment II, sampling at d 14) and on performance (Experiment III, accumulated periods of 1-14, 1-21 and 1-42 d). A total of 1344 male chicks were used. In each experiment, the birds were allotted in a completely randomised design with 8 replications. The lysophospholipids were mainly composed of lysolecithins and the organic acids blend was constituted by lactic (40%), acetic (7%) and butyric acids (1%). An interaction between lipid sources and lysophospholipids was observed on faecal apparent digestibility of lipid (ADL), which improved with lysophospholipids addition in T diets. Broilers fed on S had higher ADL and faecal apparent digestibility of nitrogen-corrected gross energy (ADGEN). It was not possible to demonstrate a significant treatment effect on the liver concentration of vitamins A and E, even with the differences in fatty acid profile between S and T. Enterobacteria values were below the detection threshold. Lysophospholipid supplementation reduced gram-positive cocci in T-fed birds. S diets promoted lower total anaerobe counts compared with T diets, independent of additives. S diets increased BW gain and feed:gain ratio in all evaluation periods. Lysophospholipids and organic acids improved feed:gain ratio at 1-21 d in T diets. Furthermore, main effects were observed for lysophospholipids and organic acids at 1-42 d, which increased BW gain and improved feed:gain ratio, respectively. No positive interactions between additives were found.

Assuntos

RESUMO

Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

RESUMO

The objective of this study was to investigate the influence of two cleaning and disinfection programs on broiler performance and on the microbiological status of the facilities. This trial was an observational study of comparative character. Two experiments were conducted, with 960 birds each. Both experiments were carried out in a positive-pressure broiler house. Broilers were distributed in pens equipped with a bell drinker and a tube feeder each. In the first experiment, new wood shavings were used as litter material, and in the second, reused wood shavings were used. Two treatments with16 replicates of 30 birds each were evaluated. The regular treatment consisted of dry and wet organic matter removal, followed by washing. The European treatment consisted of dry organic matter removal, humidification, washing with water under high pressure, detergent application, rinsing, and application of two combined disinfectants: glutaraldehyde 250g/L + formaldehyde 185g/L; p-chlor-m-cresol 210 g/L. Biosecurity measures were adopted during daily management tasks to prevent cross contamination between treatments. The effectiveness of the treatments was evaluated by microbiological analysis performed before and after treatment applications, as well as by broiler performance results. Live performance results were similar between both treatments when broilers were reared on new litter. When reused word-shavings were used as litter material, the European treatment promoted better broiler performance. The European treatment was more effective than the regular treatment in reducing total microbial counts in the facilities when reused wood shavings were used as litter material, and positively influenced broiler performance.(AU)

Assuntos

RESUMO

The objective of this study was to investigate the influence of two cleaning and disinfection programs on broiler performance and on the microbiological status of the facilities. This trial was an observational study of comparative character. Two experiments were conducted, with 960 birds each. Both experiments were carried out in a positive-pressure broiler house. Broilers were distributed in pens equipped with a bell drinker and a tube feeder each. In the first experiment, new wood shavings were used as litter material, and in the second, reused wood shavings were used. Two treatments with16 replicates of 30 birds each were evaluated. The regular treatment consisted of dry and wet organic matter removal, followed by washing. The European treatment consisted of dry organic matter removal, humidification, washing with water under high pressure, detergent application, rinsing, and application of two combined disinfectants: glutaraldehyde 250g/L + formaldehyde 185g/L; p-chlor-m-cresol 210 g/L. Biosecurity measures were adopted during daily management tasks to prevent cross contamination between treatments. The effectiveness of the treatments was evaluated by microbiological analysis performed before and after treatment applications, as well as by broiler performance results. Live performance results were similar between both treatments when broilers were reared on new litter. When reused word-shavings were used as litter material, the European treatment promoted better broiler performance. The European treatment was more effective than the regular treatment in reducing total microbial counts in the facilities when reused wood shavings were used as litter material, and positively influenced broiler performance.

Assuntos