Surface area of the tip of the enterocytes in small intestine mucosa of broilers submitted to early feed restriction and supplemented with glutamine

A total of 640 one-day-old male Cobb chicks were used to evaluate the effects of early feed restriction and glutamine on villi density and tip surface of enterocytes in the small intestine of broilers. A two-factor factorial experimental design with glutamine and feed restriction as main factors was used. Treatments consisted of quantitative feed restriction at 30% of ad libitum intake from 7 to 14 days of age, and glutamine addition at 1% in the diet from 1 to 28 days of age. Sections of the small intestine (duodenum, jejunum, ileum) were collected at 14 and 21 days of age for analyses by scanning and transmission electron microscopy. Villi density decreased with age and increased in cranial-caudal direction. Glutamine increased villi density in the small intestine. Microvilli density and height decreased with age. Glutamine increased microvilli width. The jejunum was the segment with the largest surface area of the tip of the enterocytes, followed by the duodenum and the ileum. Feed restriction decreased the surface area of the tip of the enterocytes in the small intestine at 14 and at 21 days of age. Glutamine supplemented in the feed increased the surface area of the tip of the enterocytes of the jejunum and ileum at 21 days of age. © Asian Network for Scientific Information, 2007.

Inclusão de ovo desidratado em rações para frangos de corte nas fases pré-inicial e de crescimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Physiologic values of broiler femurs at different growth phases using Bone densitometry and Bone Breaking Strength

The objective of this experiment was to determine the normal values of Bone Radiographic Density (BRD) by using the optical densitometry in radiographic images and the Bone Breaking Strength (BBS) of broiler femurs at different ages (8, 22 and 42 d of age). A total of 60 Cobb male broilers were distributed in three age groups of 20 birds. The BRD and the BBS (maxim force and rigidity) values increased (p<0.01) over the course of ages, presenting greater values at 42 d of age when comparing to 8 and 22 d of age, evidencing a biomechanical adaptation of femur to growth. This experiment offers results that can be used in other experiments of broilers fed with different nutritional levels and they can also be related to pathological values, allowing the diagnosis of diseases that affect the integrity of the poultry leg. © Asian Network for Scientific Information, 2011.

Determination of broiler femur parameters at different growth phases

The objective of this experiment was to analyse macroscopically the femur and determine the biochemical values at 8, 22 and 42 days of age, producing basic results that can help to understand the pathogeny of the locomotor problems and the broiler physiologic growth. A total of 60 Cobb male broilers were distributed in three age groups (8, 22 and 42 days of age) of 20 birds. All macroscopic measurements, except the cranial compact layer increased (p<0.05) over the course of the ages. The cranial compact layer presented the biggest measure at 22 days of age. The ash percentage increased (p<0.05) until 22 days of age, but at 42 days of age this values decreased. Calcium and phosphorus percentage in ash increased (p<0.05) until 22 days of age and evidenced constancy from 22 to 42 days of age. The biomechanical adaptation capacity of femur was evidenced by the increase of the macroscopic measures over the course of the ages and the different behavior of cranial compact layer at 22 days of age suggested an adaptation attempt of the immature bone to muscle mass increase. The ash and mineral percentage confirmed that the relative growth occurs with more intensity until 21 days of age. The calcium and phosphorus percentage evidenced the physiologic balance acting on the deposition of these minerals in femur. © Asian Network for Scientific Information, 2011.

Evaluation of a radiographic method to detect tibial dyschondroplasia lesions in broilers

This study aimed at developing radiographic techniques for the early detection of dyschondroplastic lesions in the tibia of broilers. The experiment was carried out at the facilities of UNIFOR/MG and Formiga and UNIFENAS/ Alfenas with 420 one-day-old male Cobb broilers. At 20 days of age, all birds were radiographed and identified with an alpha-numeric metal ring in the right leg. At 40 days of age, 42 broilers previously selected as a function of bone mineral density and lesion thickness scores were again radiographed and scored, and then sacrificed. Their right tibia was removed for gross and histological examination of the growth plate. The results showed that radiographic techniques are correlated with gross and histological examination and that there was no significant differences among techniques (P>0.05). it was concluded that the use of radiographic examination to identify tibial dyschondroplasia in broilers precludes the use of bone mineral density to diagnose this condition. The non-parametric statistical Chi-square test at 5% significance level was used to analyze the results.

Desempenho e morfometria duodenal de frangos de corte submetidos a diferentes níveis de energia e programas de alimentação de 42 a 57 dias de idade

This experiment was conducted to evaluate the use of different energy levels and amino acid recommendations on performance, carcass yield and intestinal morphometry of broilers from 42 to 57 days of age. We used 1,600 one-day old male broilers (Cobb 500) in a completely randomized design arranged in a 2x4 factorial scheme with 3,200 and 3,600 kcal ME/kg and four different feed programs. The metabolizable energy levels and the feed programs did not determine significant differences in carcass characteristics for choosing a level of energy or a feed program, thus the energy level and the recommendations of amino acids that determine the highest cost-benefit ratio should prevail. It was observed that 3,600 kcal ME/kg resulted in some improvement on performance and morphometry of the intestinal mucosa, also the fractioning of digestible amino acid requirements during two periods resulted in worse performance and intestinal villi height.

Relationship between incubation temperature and egg size with heart hypoplasy in broiler chicks at hatching

It was analyzed if the effects of continuous incubation temperature deviations during the second half on the development of body, organs and hematological respiratory and energetic parameters differ between male and female from 30- and 60-week-old breeder eggs. From day 13, Cobb eggs were exposed to 36°C, 37.5°C, or 39°C. At 3, 6, 12, 24, 48 and 72 h after this change in the temperature and at hatch, red cells count, hematocrit, hemoglobin, mean corpuscular volume, plasma glucose level and body, liver and heart weights were evaluated. Independent of incubation temperature, sexes and breeder ages, mean corpuscular volume decreased and the other variables increased during late incubation. In 30-week-old breeder eggs, body weights and erythrocytic parameters were not influenced by temperature but liver and heart weights decreased increasing incubation temperature and glucose level increased at 36 and 39°C. In 60-week-old breeder eggs, males were heavier at hatching with incubation at 36°C and females had smaller body weights with incubation at 39°C. In both sexes, liver weight decreased and glucose concentration was higher at 36 and 39°C and heart weights and erythrocytes parameters were not influenced by temperature. Independent of breeder age, hatchability was lower at 39°C. The data show that high temperature from day 13 of incubation reduced more intensively the hatching success and caused cardiac hypoplasia in chicks from 30-week-old breeder eggs only, revealing for the first time that the susceptibility for ascites syndrome, by reduced heart development at hatching, is associated to a relationship between incubation temperature and egg size. © Asian Network for Scientific Information, 2012.

Evaluation of tibial dyschondroplasia development in broiler chickens fed diets containing 25 hydroxicolecalciferol

This research was carried out to evaluate the development of tibial dyschondroplasia (TD) in broilers from 1 to 21 days. Four hundred forty day-old male chickens, from broiler breeders aged 60-62 weeks, were randomly distributed in a 3×3+2 factorial arrangement, resulting in 11 treatments with four replicates of 10 birds each. The factors evaluated were: bird strains (Ross 308, Cobb 500, and Hybro), levels and sources of vitamin D (1250UI D3/kg without 25-(OH)D3; 1250UI D3/kg with 69mg 25-(OH)D3/ton, and 3000UI D3/kg with 69mg 25-(OH)D3/ton), and two control treatments containing calcium and phosphorus levels with 3000UI D3/kg without 25-(OH)D3 and 3000UI D3/kg with 69mg 25- (OH)D3/ton of feed. Bone characteristics were evaluated. From 1 to 21 days, the results showed that bone calcium and phosphorus concentrations were not influenced by the treatments, however, feed intake was higher for factorial than control treatments. Bone breaking resistance was not influenced by the treatments and there were no typical lesions of TD. In conclusion, it was not observed TD development in broilers from 1 to 21 days according to experimental procedures of this research.

Effects of corn replacement by sorghum in broiler diets on performance and intestinal mucosa integrity

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da suplementação de betaína em dietas de frangos de corte em condições de termoneutralidade

The aim of this study was to evaluate the effect of inclusion of betaine in broiler diets on performance and intestinal morphology of broilers during periods 1 to 7 and 8 to 21 days old. Were used 1,408 Cobb male broiler, randomly assigned into 4 treatments with 16 replicates of 22 birds in environmental chambers. The treatments were: i) positive control - diet formulated according to the nutritional requirements of the birds; ii) negative control - with reduction levels of methionine and choline; iii) negative control + 0.092% supplementation of betaine in substitution of methionine and total choline; iv) negative control + 0.1% supplementation of natural betaine to replace partial methionine and total choline. Were evaluated feed intake, weight gain and feed conversion at 7 and 21 days old. At 25 days were evaluated crypt height and depth of jejunum. The results were analyzed by ANOVA and mean comparison test. The results obtained with the supplementation of betaine in the feed only demonstrated a positive effect on feed consumption during 1 to 7 days, and villous height of the jejunum in the period of 8 to 21 days. Supplementation of 0.1% betafin (96% natural betaine) in the diet provided significant improvements in the morphological characteristics of the small intestine of broilers.

Effect of pectin extracted from citrus pulp on digesta characteristics and nutrient digestibility in broilers chickens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Broiler breeder feeding programs and trace minerals on maternal antibody transfer and broiler humoral immune response

Breeder feed restriction may negatively affect broiler progeny immunity. Sources of trace minerals (TM) with higher bioavailability in breeder diets have been reported to enhance humoral and cellular immunity in broiler progeny. An experiment was conducted to examine the effects of breeder feeding programs and TM dietary sources on maternal antibody transfer and humoral immune response of progeny to a live vaccine against Newcastle disease virus (NDV). Cobb 500 breeders were fed according to 2 feed allocation programs, sigmoid late fast and sigmoid late slow, from 14 to 29 wk of age. From 56 to 62 wk of age, breeders were fed with either inorganic TM or an organic source (OTM) to replace 30% of Cu, Zn, and Mn. Progeny broilers were vaccinated intraocularly with La Sota NDV vaccine at 7 d of age. Blood samples were collected at hatching, 4, and 14 d postvaccination. Serum antibody levels against NDV were assessed by ELISA and cytokine expression by real time PCR. At hatching, late slow breeder progeny fed diets with 30% OTM had higher antibody titers as compared with progeny of breeders fed 100% inorganic TM. Similar results were observed 2 wk postvaccination. Breeder feeding programs and TM sources affected the expression level of IL-4 in NDV vaccinated broiler progeny. It was concluded that breeder feeding programs influenced humoral immune response to NDV vaccine in the broiler progeny, and 30% OTM may increase these responses. © 2013 Poultry Science Association, Inc.

Digestible tryptophan requirements for broilers from 22 to 42 days old

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação de diferentes programas de restrição alimentar para matrizes pesadas

Pós-graduação em Zootecnia - FCAV

Efeito da pectina cítrica sobre o desenvolvimento e a saúde do intestino delgado de frangos de corte

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)