Resumo em Inglês:

ABSTRACT Avian Infectious laryngotracheitis (AILT) is a respiratory tract disease of great importance because it causes significant economic losses in the poultry industry around the world. It is caused by a Gallid herpesvirus type 1, a member of the genus Iltovirus. The target system for Avian Infectious Laryngotracheitis virus (AILTV) infections is the respiratory system, and the main organ in which the virus remains latent is the trigeminal ganglia. However, the virus has demonstrated tropism for other organs besides the respiratory tract. The main transmission routes are ocular and respiratory. Infected birds with clinical symptoms are main sources of transmission, but birds with latent infections, litter, and contaminated fomites may also transmit the virus. Clinical signs usually appear 6-12 days after natural exposure and may be moderate or severe. The causative agent of this disease can be propagated in chorioallantoic membrane (CAM) of developing chicken embryos and replicate in mature chicken kidney cells, as well as in a variety of epithelial chick embryo cells, such as kidneys, liver and lungs. There are several procedures for the diagnosis of ILT such as the observation of clinical signs, the detection of gross and histopathological lesions, and the use of molecular techniques, including RFLP, polymerase chain reaction (PCR), real-time PCR, and loop-mediated isothermal amplification. Vaccination with different types of vaccine provides a good expectation on disease control, such as vaccines produced in chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and recombinant vaccines. However, in endemic areas, biosecurity measures and best management practices are important for the control of the disease. It is distributed worldwide and, in South America, it has been reported in Brazil, Peru, Ecuador, Bolivia, and Argentina causing great economic losses.

Resumo em Inglês:

ABSTRACT In broiler production, the litter is reused for consecutives flocks, and it is treated during down time between flocks to reduce its microbial load. Although covering the litter with a plastic canvas is a common litter treatment in the field, there is little scientific information available on its efficacy. The aim of this study was to evaluate the effects of covering broiler litter with a plastic canvas for eight days on litter microbiological, physical, and chemical parameters, and on the intestinal microbiota and immunity of broilers. In the first trial, reused litter from a previous flock was distributed into three treatments, with six replicates each: L1 (negative control, litter free from Salmonella Enteritidis (SE) and Eimeria maxima (EM) and not covered), L2 (positive control, litter with SE and EM, and not covered), and L3 (litter with SE and EM, and covered with plastic canvas for eight days). Litter total bacteria, Enterobacteria, Lactobacillus, SE, and EM counts, and litter pH, temperature, moisture, and ammonia emission were determined on days 1 and 8. In the second trial, broilers were housed on those litters according to the treatments described above, and their intestinal microbiota, gut CD4+ and CD8+ lymphocytes and macrophages, and liver and intestinal pro-inflammatory interleukin (IFN-γ, IL-1β e IL-18) levels were evaluated on days 14 and 28. A significant reduction of litter bacterial populations was observed in the litter covered with plastic canvas. A significantly higher mRNA IFN-γ gene expression (12.5-fold) was observed in the jejunum and liver of broilers reared on the litter with Enterobacteria counts. No EM reduction was observed in the covered litter. Covering reused broiler litter with plastic canvas reduces initial litter bacterial load as a result of the interaction between physical and chemical parameters.

Resumo em Inglês:

ABSTRACT Locomotion problems in broiler chickens can cause economic losses of up to 40% of the total revenues due to carcass condemnation and downgrading at processing. Leg disorders, such as femoral lesions, tibial dyschondroplasia, and spondylolisthesis, substantially impact the welfare of chickens as these disorders can prevent birds from reaching the feeders and drinkers, thus reducing feed and water intake. The most important issues related to broiler welfare reported in the last two decades are their growing sensitivity to metabolic and locomotion problems due to the fast growth rates and inactivity. Traditional methods for the determination of gait score include the manual scoring of animal behavior in the broiler house. Recorded video images can also be used for manual scoring of chicken gait score. However, scoring of some animal-based information by human experts and manual methods remain difficult, time consuming and expensive when implemented at farm level. In an effort to objectively detect leg disorders, this study aimed at validating the photogrammetry technique as a non-invasive method for identifying locomotion problems in broilers. Photogrammetry allows determining the geometric properties of broilers from digital photos that are processed and analyzed using a computer software. Results obtained using photogrammetry were tested for their correlation with those obtained by accepted methodologies, including gait score and macroscopic examination of femoral degeneration and tibial dyschondroplasia. The photogrammetry results agreed with the results of the afore mentioned accepted methods.

Resumo em Inglês:

ABSTRACT Egg production is an important economic activity in Brazil, with about 697 million eggs produced annually. The conventional cage system is commonly used for egg production. However, there has been a growing concern for the welfare of laying hens around the world. In this context, many countries have issued laws, protocols, and other normative technical specifications to ensure the welfare of layers. This study aims at identifying similarities and differences between international standards and Brazilian protocols using the Comparative Law perspective. This article reports an analytical study of selected protocols, performing three analyses using the Comparative Law method. The research concludes that some items of the Brazilian protocols of good egg production practices, such as farm inspection, treatment of diseases, temperature, ventilation, beak trimming, feed and water supply, correspond to international specifications, whereas others, such as housing, freedom movement, use of equipment, and transport, are less strict.

Resumo em Inglês:

ABSTRACT Long storage periods may increase embryo mortality. The objective of this study was to evaluate the effects of storage period on the weight loss, eggshell surface temperature, hatchability, and embryonic mortality of Japanese quail eggs. Two hundred fertile eggs were collected from a flock of 30-week-old Japanese quails (Coturnix coturnix japonica). The eggs were collected for 10 consecutive days after lay, and immediately incubated. A completely randomized experimental design with 10 treatments, corresponding to the number of days eggs were stored between egg collection and setting, with 20 replicates each, was applied. Egg weight loss increased with storage period duration, starting on day 6 (2.1%, on average) and reached 3.26%, on average, in eggs stored for 10 days. The highest hatchability (p>0.05) was obtained in eggs stored for two days, which also lost the least weight (1.20%). Storage period did not influence eggshell surface temperature (p>0.05) during incubation, but higher temperatures (p<0.05) were measured on days 10 and 15 of incubation compared with day 5. Eggs stored for ten days presented the highest weight loss, and therefore, a storage period of up to five days is recommended to maintain the quality of incubated Japanese quail eggs. Furthermore, egg surface temperature increases during the second half of the incubation period as a result of increasing embryonic metabolic rate.

Resumo em Inglês:

ABSTRACT An experiment was conducted to determine the effects of the dietary inclusion of different levels of thymoquinone (TQ) of broilers subjected to oxidative stress or not on the antibody titers against Newcastle disease and on the gene expression of interleukine-1 and interferon gamma. A total of 320 one-day-old broilers was randomly assigned to eight treatments with four replicates of 10 birds each, in a 4 × 2 factorial arrangement, consisting of four thymoquinone (TQ) levels (0, 5, 8, or 11 mg/kg body weight) and two levels tert-butyl hydroperoxide (t-BHP) injection (0 or 0.02 mmol/kg of body weight). Blood samples were collected from two birds per replicate to determine antibody titers against Newcastle disease. At the end of experiment, two birds per replicate were randomly selected, sacrificed and their spleens were collected to evaluate the genes expressioninterleukin-1 and interferon gamma (p<0.05). The dietary inclusion of TQ of broilers subjected or not oxidative stress increased antibody production against Newcastle disease (p<0.05). Both individual and combined dietary inclusion of t-BHP and TQ promote the differentiation and proliferation of spleen cells and the gene expression of interleukin-1 and interferon gamma (p<0.05).

Resumo em Inglês:

ABSTRACT The present study was carried out to determine the effects of the inclusion of a spore-forming probiotic (Bacillus subtilis) in laying Japanese quail diets as an alternative to growth-promoting antibiotics to help produce healthy eggs and meat. This experiment was conducted as a completely randomized design with three treatments (control, 0.05% bacitracin methylene disalicylate (BMD), or 0.1% Bacillus subtilis) of five replicates of 11 quails each. Feed intake and egg production were recorded daily on cage basis. Body weight was determined at the beginning and end of the trial (36 and 42 weeks). At the end of the experiment (42 weeks), antibodies against Newcastle disease and avian influenza, egg components, Haugh units, eggshell quality and breaking strength, blood parameters, cecal microbial population, villus length, and crypt depth were measured. The dietary inclusion of Bacillus subtilis and BMD significantly (p≤0.05) increased egg production and egg weight; however, eggshell thickness and breaking strength, Haugh units, and eggshell percentages were not affected. The dietary addition of both products significantly (p≤0.05) decreased plasma cholesterol levels and increased LDL levels, as well as antibody levels against Newcastle disease and avian influenza (p≤0.01). In birds fed Bacillus subtilis and BMD, crypt depth was reduced, but villus height and villus to crypt ratio were significantly increased (p≤0.001) compared with those fed the basal diet. Cecal coliforms, E. coli, and Salmonella counts were reduced (p≤0.01) in quails fed the diets containing Bacillus subtilis and BMD compared those quails fed the non-supplemented diet. The results of this study demonstrated that in absence of AGPs, the inclusion of a spore-forming probiotic partially improves the performance of laying quails.

Resumo em Inglês:

ABSTRACT Thermal manipulation (TM) during broiler chicken embryogenesis has been shown to promote muscle development and growth. However, the molecular bases of promoting broiler muscle development and growth are not fully understood. The aim of this study was to investigate the molecular bases of muscle growth and development in broiler chickens subjected to TM. This included the investigating of the changes in mRNA expression levels of muscle marker genes, namely MyoD, myogenin, paired box transcription factor (Pax7) and proliferating cell nuclear antigen (PCNA), and muscle growth factors namely insulin-like growth factor 1 (IGF-1), myostatin and growth hormone (GH) during embryogenesis and on posthatch days 10 and 28. Fertile Cobb eggs (n=1500) were divided into four groups. Eggs in the first group (control) were incubated at 37.8°C and 56% RH, whereas, eggs in the second group (TM1), third group (TM2), and fourth group (TM3) were subjected to 39 ºC and 65% RH daily during embryonic days (ED) 12-18 for 9, 12, and 18 hours, respectively. Body weight (BW) during embryogenesis and posthatch days (1, 3, 5, 7, 14, 21, 28 and 35) was recorded. mRNA expression levels of muscle marker genes and muscle growth factor genes during ED 12, 14, 16 and 18 and on posthatch days 10 and 28 were analyzed using real-time RT-PCR. TM upregulated the mRNA expressions of muscle marker and growth factors genes. This upregulation was accompanied by improvement of body weight near and at market age.

Resumo em Inglês:

ABSTRACT The objective of this study was to identify the growth curve of live weight of turkeys reared in different systems (intensive and free- range) with the best mathematical model. To achieve this goal, the live weight of male and female turkeys (Large White) reared for 0-18 weeks were used. Logistic, Gompertz, Von Bertalanffy, and Gauss were used to determine the best model for the turkeys. In comparison of the models, values of Coefficient of Determination (R2), Mean Squares of Error (MSE) and Model Efficiency (ME) were used. In Von Bertalanffy model, the coefficient of determinations for males and females were found as 0.9974 and 0.99915 in intensive system and 0.9794 and 0.9804 in Free-Range system, respectively. As a result of this study, because the highest R2 and the lowest MSE were observed in Von Bertalanffy model, it was the best among the models to identify growth curve of the turkeys.

Resumo em Inglês:

ABSTRACT This study aimed at evaluating if essential oils misted in broiler houses reduce environmental fungi counts. The investigation was conducted in three experimental rooms, where broiler chickens were reared between 1 to 42 d of age. Every three days, the rooms were fogged with pure water (control) or with aqueous solutions of peppermint or thyme oils. On the next day, fogging samples from the air, flat surfaces, and litter were collected and quantitatively and qualitatively analysed for fungal contamination. The treatment with essential oils showed promising results. In the room fogged with thyme oil, aerial fungi growth was not as evident as in the control room, and presented the lowest average fungi count. Thyme oil was also the most effective in reducing fungi colonization on drinker surfaces and litter. The use of peppermint oil also reduced the population of air, wall, surface and litter fungi, although some exceptions were noted. Aspergillus, Penicillium, Fusarium and Saccharomyces genera were identified most frequently. The effect of essential oils was noticeable in the last two weeks, when the counts of Aspergillus sp. were 75% (thyme oil) and 46% (peppermint oil) lower in comparison with the control group. The results show that fogging broiler houses with essential oils may be an effective prevention method against fungal aerosol in broiler houses. However, further investigations to determine the synergistic effect of different oils and their compounds, and the best possible doses and methods of application in the field are needed.

Resumo em Inglês:

ABSTRACT The aim of this study was to determine the effects of the replacement of different levels of protein derived from soybean meal with that from peas in broiler diets on serum protein fractions. A corn-soybean meal basal diet was formulated as the control diet (Control=C) (NRC, 1994), and then pea was added to the control diet to replace 20% (P20) or 40% (P40) of the crude protein of the control diet. The diets were randomly fed to 12 pens per treatment, each housing five birds, for 42 days. Blood samples were collected from 36 birds (3 birds x 4 pens x3 treatments) and the serum protein fractions were separated. Gamma-globulin percentage was higher in group P20 compared with C and P40 groups. Total protein, beta-globulin, and gamma-globulin concentrations were significantly higher in group P20 compared with those of both control and P40 group (p<0.05).

Resumo em Inglês:

ABSTRACT This experiment aimed to evaluate the utilization of firewood ash as calcium source in the initial diet of broiler chickens. One hundred and twenty eight broiler chickens of Cobb-500® strain, from 1 to 21 days of age, were randomly distributed in four treatments with four repetitions of eight birds each, been four female and four male. The experimental diets were corn-soybean based, been isoenergetic and isonutrients, and had 0, 0.32, 0.98 and 1.27% of firewood ash as calcium source. The firewood ash utilized had 23.8% of calcium, 0.39% of total phosphorus, and 0.11% of sodium. The experimental treatments did not influence the feed intake, body weight, body weight gain, and food conversion from 1 to 7, 1 to 14, and 1 to 21 days of age. The tibia and femur thickness and length at 21 days of age were not altered by treatments. It was concluded that the firewood ash can be used as calcium sourcereplacing limestone in the initial diet of broiler chickens, without change the performance and the bone development.

Resumo em Inglês:

ABSTRACT Lead (Pb) is a heavy metal, which adversely affects thyroid gland function and structure. Due to its high molecular weight and abundant functional groups, humic acid substances (HAS) can form chelates with heavy metals. The experiment was conducted to evaluate the prophylactic effect of HAS on thyroid hormone levels and histopathological lesions of laying hens exposed to lead (Pb) poisoning. After a week of adaptation, 192 Lohmann White laying hens (25 weeks of age) were fed one of four diets: a basal diet (BD) or the BD with HAS (0.15%), with Pb (0.3 g/kg), or with both. Experimental groups were replicated in 12 cages, with four hens each. Pb poisoning did not alter triiodothyronine (FT3; 3.22 ± 0.20 ng/dL) or thyroxine (FT4; 0.71 ± 0.08 ng/dL) concentrations, but caused a 167% increase in thyroid stimulating hormone (TSH) concentration. HAS supplementation returned the high TSH levels of hens exposed to Pb poisoning to normal values. Degenerative changes in the epithelial cells of the thyroid gland of the hens exposed to Pb poisoning were evidenced. Connective tissue cells in the interfollicular area and total amount of colloids with partially atrophic follicles were observed. These histopathological findings were less severe when HAS was added to the diet. In conclusion, HAS alleviates the effects of Pb poisoning on thyroid gland function and structure, possibly preventing its internalization by the tissue by forming chelates and exerting anti-inflammatory effects.

Resumo em Inglês:

ABSTRACT The 4-week study was conducted with 180 Lohmann Brown layers (52 weeks of age). The layers were assigned to three groups (C, E1 and E2). The basal diet (group C) consisted mainly of corn, soybean meal and corn gluten, and contained 19% crude protein and 11.58 MJ/kg metabolizable energy. The diets for groups E1 and E2 differed from group C by the inclusion of 5% flax meal and of dietary antioxidants. The concentration of α-linolenic acid in the fat of E1 and E2 diets was almost 10 times higher than in group C. E1 diet was supplemented with vitamin E (100 mg/kg feed, DM), while E2 diet was supplemented with 2% grape seed meal (polyphenols: 630.890 µg gallic acid equivalents/g sample; flavonoids: 5.065 µg rutin equivalents/g sample; antioxidant capacity: 28.468 mM trolox equivalents/g sample). The antioxidant capacity of E2 was higher than in C, but lower than in E1. Haugh units of the eggs (18 eggs/group) harvested during the last experimental week were not significantly different among groups. The ω-6/ω-3 polyunsaturated fatty acids (PUFAs) ratio in the fat from the eggs was 4.46 ± 0.11 (E1) and 4.52 ± 0.21 (E2), three times lower (p<0.05) than the control group (14.70 ± 0.43). In group E1 in particular, but also in group E2, the concentration of total polyphenols in the egg yolk was higher (p<0.05) than in group C.

Resumo em Inglês:

ABSTRACT Ninety-six 28-week-old Lohmann White laying hens were utilized to test the antioxidant effects of flavonoids (hesperidin, naringin, and quercetin at 0.5 g/kg diet) during an 8-wk experimental period. At the end of the experiment blood samples were collected to determine total protein, cholesterol, and malondialdehyde (MDA) serum levels as well as activities of glutathione reductase (GR), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST), and superoxide dismutase (SOD) and level of glutathione (GSH) in erythrocyte lysates. Data were analyzed using one-way ANOVA. Naringin supplementation did not alter serum cholesterol concentration, whereas hesperidin and quercetin supplementations decreased serum cholesterol concentration. Naringin and quercetin supplementations did not affect serum protein concentration. All flavonoids decreased MDA concentration as well as increased GSH-Px, GR, GST, and SOD activities and GSH level, being quercetion superior to hesperidin and naringin. In conclusion, flavonoids, especially quercetin, exert antioxidant activity, which may help improve wellbeing when laying hens are exposed to stressors.

Resumo em Inglês:

ABSTRACT In order to evaluate the antioxidant effects of barbatimão (BAR) or pacari (PAC) on chicken meat oxidative stability and quality, seven dietary treatments containing in three different BAR and PAC concentrations (200, 400 and 600ppm) plus a negative control (CONT) were fed to 350 broilers from 1 to 41 days of age. Ten birds per treatment were slaughtered to collect breast and thigh meat to evaluate pH, color (L*, a*, b*), cooking weight loss (CWL), and shear force (SF) 24 hours postmortem, and TBARS levels in precooked meatballs stored chilled for 8days. The dietary supplementation with BAR and PAC extracts did not affect pH and color, but reduced (p<0.05) SF in breast meat compared with CONT suggesting improved tenderness. PAC200 increased (p<0.05) L* and protected (p<0.05) yellow pigments (b* values) of thigh meat from degradation compared with the CONT diet. At the end of the chilled storage period, BAR600 and PAC600 significantly reduced (p<0.06) MDA concentrations in breast meatballs compared to the CONT. The dietary supplementation of BAR and PAC improved (p<0.03) oxidative stability of thigh meatballs, except for BAR200. In conclusion, the dietary addition of BAR and PAC extracts may improve meat quality and prevent lipid oxidation in white and dark precooked and chilled chicken meatballs.

Resumo em Inglês:

ABSTRACT This study was conducted to evaluate the effects of coenzyme Q10, L-carnitine and ractopamine supplementation, alone and in combinations, on carcass traits and immune response of broiler chickens. Five hundred and twelve one-day-old Ross 308 male broiler chickens were randomly allocated into eight treatments with four replicates each. A 2×2×2 factorial arrangement was applied, with two levels of coenzyme Q10 (0 and 40 mg/kg), two levels of L-carnitine (0 and 200 mg/kg) and two levels of ractopamine (0 and 10 mg/kg). The birds were reared until day 42 of age under standard conditions. Blood samples were collected at the end of grower and finisher periods from the wing vein. Four birds per group were sacrificed at day 42 of age. Except for carcass yield, other carcass traits were not significantly affected (p>0.05) by different levels of coenzyme Q10, L-carnitine, or ractopamine. Immune response parameters were significantly (p<0.05) different between the treatments. The lowest antibody titers against Newcastle disease virus and relative spleen weight were observed in control group. The results of this study suggest that addition of coenzyme Q10 and L-carnitine to broiler diets has benefit effect on immune response of broiler chickens.

Resumo em Inglês:

ABSTRACT The current experiment was conducted to evaluate the effect of stocking density (SD) on the performance and immunity of 1- to 14-d-old broilers. A total of 1836 one-day-old Cobb 500 broilers were housed at four different SD (30, 60, 90 and 120 chicks/m2). Body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were estimated on d 2, 5, 8, 11 and 14. Relative lymphoid organ weights, maternal antibody titers against IBV, IBD and NDV, and stress indicators were estimated on d 3, 6, 9 and 12.The results indicated that age significantly (p<0.001) affected the performance and immunity of broiler chicks. Stocking density significantly (p<0.001) affected the performance and physiological stress indicators of broiler chicks, but not maternal immunity, relative lymphoid organ weights, or blood glucose levels. A significant interaction between age and density was determined for BWG, FI and FCR, and maternal antibody titers against IBD and NDV. The results also indicated that the effects of SD were age-dependent: as SD increased, worse performance, lighter lymphoid organs, and stronger stress responses were observed as broilers aged. It is concluded that the higher the SD during the first two weeks of life, the worse is the performance as broilers age.

Resumo em Inglês:

ABSTRACT Salmonella species have been isolated from various kinds of food and are accountable for outbreaks of foodborne diseases in humans. This study aimed at identifying the similarities between the DNA profiles of Salmonella isolated from chicken feces, chicken products, and human feces in southern Brazil. Six hundred samples were collected (200 from chicken products, 200 from broiler chicken feces, and 200 from human feces) and tested for the presence of Salmonella. Isolates proven to be Salmonella compatible by biochemical and serological tests were tested by the Polymerase Chain Reaction. Their DNA profiles were then analyzed by PFGE and rep-PCR. Salmonella was isolated from 16 out of 600 analyzed samples, with Schwarzengrund serotype presenting the highest incidence, followed by Mbandaka in chicken meat and fecal samples, and Panama in human fecal samples. Some strains isolated from chicken fecal and product samples were indistinguishable by the molecular methods used in the study, suggesting that that the contamination of the broilers on the farm can be transmitted the processed products.

Resumo em Inglês:

ABSTRACT Pathogens of veterinary and medical importance were investigated in 240 feral pigeons (Columba livia) captured in warehouses in São Paulo State, Brazil for one year. Rapid serum agglutination test (RST) was performed for the detection of antibodies against Mycoplasma synoviae, Mycoplasma gallisepticum and Salmonella Pullorum/Gallinarum. Positive samples were submitted to hemagglutination inhibition (HI) and tube seroagglutination tests, respectively. Molecular techniques (RT-PCR and PCR) were performed for Newcastle Diseases Virus (NDV) and Chlamydia psittaci diagnosis. Additionally, HI test was applied to detect antibodies against NDV. Serological results by RST were 3.3% positive for M. synoviae, 2.5% for M. gallisepticum, and 0.4% for S. Pullorum/Gallinarum, all negative on the confirmatory tests performed. NDV RNA or antibodies were not detected. C. psittaci DNA was detected in 13% of the samples. Further research on pigeon health status should be conducted because this species is highly adaptable and their numbers are rapidly rising around the world, posing risks for animals and human beings.

Resumo em Inglês:

ABSTRACT The effect of egg powder inclusion in the pre-starter diet (1-7 days of age) on the performance, and intestinal morphology and microbiology of male broiler chickens was evaluated in a completely randomized design. Starter diets with equal metabolizable energy and crude protein levels were formulated to contain 0, 20, 40, or 60 g egg powder/kg diet. Results showed that body weight, feed intake, feed conversion ratio, and European efficiency index were positively affected (p≤0.05) by egg powder inclusion in the starter diet. Inclusion of 40 g egg powder/kg diet in the starter diet promoted the best performance results. Jejunal villus height and villus to crypt ratio increased (p≤0.05) and intestinal length decreased (p≤0.05) as a result of egg powder inclusion in the starter diet. Egg powder inclusion in the starter diet reduced (p≤0.05E. coli counts, but increased (p≤0.05) lactic acid bacteria counts in the small intestine. The results obtained in the present study indicate that the inclusion of 40 60 g egg powder/kg of starter diet g improved the performance and intestinal health of broilers.

Resumo em Inglês:

ABSTRACT The aim of this study was to evaluate the effects of forced molting using biochemical parameters and histopathological findings in laying hens. 36 Hyline W36 strain laying hens, 90 weeks old were chosen for this research. Eight of these chickens were randomly selected and placed in a cage as the control group before the molting program began. All the others 28 chickens were used for the forced molting program. Eight laying hens were slaughtered at the end of the molting program named as molting group. The remaining 20 hens were fed for 37 days, weighted and slaughtered when they reached the maximum egg production (80%) as postmolting group. Then, blood was analyzed for malondialdehyde, glutathione, catalase, glucose, calcium, phosphorus, albumin, globulin, total protein, triiodothyronine, thyroxine and Vitamin C. The malondialdehyde and glutathione levels of the thyroid and liver tissues were also analyzed along with an examination of the histopathological changes of the liver, ovarium and thyroid glands; and live body, liver, ovarium, thyroid weights and thyroid lengths. In conclusion, it was found that forced molting produces stress and notable side effects in hens, like the oxidant and antioxidant status of the organs, tissue weights and sizes, hormon profiles, blood biochemical and histopathological parameter changes. The activities of thyroid malondialdehyde (p<0.05), liver glutathione (p<0.01), plasma catalase (p<0.001) were significantly decreased in molting group compared to control values, while liver malondialdehyde levels were significantly increased (p<0.001) and thyroid glutathione levels had nonsignificant effect. These levels in molting hens were the first study for veterinary science.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose.

Resumo em Inglês:

ABSTRACT Two experiments were performed to evaluate the hematological and blood biochemistry parameters, biometry of digestive organs, enzyme activities, protein content and absolute weight of the pancreas of broilers fed pre-starter and pre-starter diets supplemented or not with amylase from Aspergillus awamori. In total, 120 male Cobb chicks were housed in heated cages in each experiment. A completely randomized experimental design, with two treatments (feed with and without amylase) and six replicates per treatment of 10 birds each was applied. The data were subjected to analysis of variance using the F-test at 5% probability level. The dietary amylase addition did not affect hematological and blood biochemistry parameters and the biometry of the gastrointestinal tract of 7- and 21-d-old broilers, nor the absolute weight, enzyme activities or protein concentration of the pancreas of 7-d-old broilers. However, the inclusion of amylase in the diet reduced amylase activity and pancreatic protein concentration in 21-d-old broilers. The application of amylase to broiler chicken pre-starter and starter feeds is not justified given the pancreatic amylase activity and protein concentrations.

Resumo em Inglês:

ABSTRACT In this study, 240 one-d-old Arbor Acres broiler chicks (160 males and 80 females) were randomly allocated in a completely randomized design with four treatments and four replicates. Broilers were fed from hatching to 28 d of age four diets: a basal diet (control), 2% red ginseng marc, 1% fermented red ginseng marc with red koji, and 2% liquid red ginseng. Growth performance and fatty acid profiles in broiler were evaluated. Supplementing diets with different types of red ginseng did have significant effects (p<0.05) on initial body weight, due to differences in the birth weights of birds, including weight gain, and mortality. However, no significant differences between the treatments (p>0.05) were found for final body weight, feed intake, and feed conversion. In addition, supplementing broiler diets with different types of red ginseng did not significantly influence (p>0.05) fatty acid profiles in either breast or thigh meats. We concluded that growth performance (weight gain and mortality) was most enhanced in diets supplemented with 1% fermented red ginseng powder combined with red koji.