Abstract in English:Brazil is one of the world's largest countries with a rich diversity of wildlife, including resident and migratory wild birds, which may be natural reservoirs of the Newcastle disease virus (NDV). Because Brazil is a major global exporter of chicken meat, the emergence of such a disease may have a huge negative impact not only on the economy due to trade restrictions and embargoes, but also on the quality of life of the population. Samples were collected from 1,022 asymptomatic domestic and wild birds from the Brazilian coast and the Amazon region using tracheal/cloacal swabs and tested by RT-qPCR. The results showed 7 (0.7%) birds were positive for NDV. The positive samples were then isolated in embryonated chicken eggs and their matrix protein genes were partially sequenced, revealing a low-pathogenicity NDV. This study confirms the maintenance of the velogenic-NDV free status of Brazil.
Abstract in English:Two experiments were carried out to study the effect of breeder age on incubation parameters (hatchability, eggshell thickness, egg surface temperature and chick weight). In Exp. 1, fertile eggs (30- and 60-wk-old breeders) were incubated at three different temperatures (36.8, 37.8 and 38.8 ºC). Eggshell surface temperature was measured by attaching a thermocouple to the shell and data were collected in a datalogger every ten minutes. This study was conducted according to a 3 x 2 factorial design (three temperatures and two breeder ages). Data revealed that eggshell surface temperature changed according to incubation temperature, with the main increase occurring between 10 and 13 days of incubation, and that the maximum increase in eggshell surface temperature was not higher than +0.6 ºC, irrespective of incubator temperature. The incubator temperature affected total incubation period and hatchability (%) at 38.8 ºC, independent of breeder age. Heavier eggs resulted in heavier chicks, irrespective of incubator temperature. In Exp 2, the eggs (30- and 60-wk-old breeders) were incubated at 37.8 ºC and eggs characteristics (weight, specific gravity, total hatchability and chicks weight) were evaluated according to a randomized experimental design. The data showed that breeder age affected eggshell thickness and chick weight (heavier eggs resulted in heavier chicks), but not specific gravity, eggshell surface temperature or hatchability. The findings of this study revealed that hatchability can be influenced by incubation temperature, but not by the breeder age. Breeder age can affect eggshell thickness, egg weight and eggshell surface temperature, but not specific gravity.
Abstract in English:This study was conducted to investigate the effects of the replacement of drinking water by herb infusions on the performance, relative weight of internal organs, hematocrit and immune response to Newcastle disease virus of broiler chickens. A total of 540 male broiler chicks (Ross 308) were divided into five groups, corresponding to four different treatments and one control group. Treatments were replicated eight times, and the control group four times. Experimental treatments included infusions (5 grams per liter) of cinnamon, thyme and turmeric in equal ratios in replacement of drinking water. Experimental period lasted 21 days and all chicks were fed with a corn-soybean based diet. Results showed that all herbs infusions caused significant (p<0.05) decrease in live body weight compared with the control group at 21 days of age. Mix treatment significantly decreased relative carcass weight relative to the control group (p<0.05). Herbs infusions increased the relative weight of some organs. None of herb additives affected hematocrit in comparison to control group. Cinnamon and herb mix infusion significantly improved bird immune response to the NDV vaccine in comparison to the control group and those that received only turmeric infusion. When all in-water additives were compare to each other, the birds supplemented with turmeric infusion showed the worst performance and immunity. The results of this experiment suggest that these herbs infusions did not favor the performance of broiler chickens.
Abstract in English:The present study aimed at evaluating the histo-morphological changes resulting from different fasting periods before the collection of tissue samples in different segments of the small intestine (duodenum, jejunum and ileum) of 7-d-old male chicks of a broiler and a layer strain. A completely randomized experimental design in in a 2x7 factorial arrangement, being two strains with different growth rates (Ross 308 and HyLine® W36) and seven fasting periods (0, 2, 4, 6, 8, 10 and 12 hours ), with six replicates, totaling 84 birds. The comparison of the morphometrics of the duodenum, jejunum and ileum of broiler and layer chicks demonstrated faster digestive tract development in broilers relative to layers. The fasting period caused morphological changes in the liver and small and large intestines in both strains. Therefore, it must be highlighted that in studies involving organ weights and intestinal morphometrics, birds must not be submitted to fasting before tissue collection.
Abstract in English:The aim of this study was to evaluate the effects of different litter materials on litter compaction, broiler feathering and the incidence of carcass lesions. In the experiment, 3240 one-day-old Ross® chicks were selected by sex and distributed according to a completely randomized experimental design in a 2 x 6 factorial arrangement (two sex and six litter materials). The following litter materials were used: wood shavings, rice husks, chopped Napier grass, 50% sugar cane bagasse plus 50% wood shavings, 50% sugar cane bagasse plus 50% rice husks, and pure sugar cane bagasse. Litter compaction was weekly assessed using a penetrometer. On days 21, 35 and 42 of the experimental period, feathering on the back and legs was scored according to a 0 - 10 scale. On day 42, birds were slaughtered and the presence of bruises, scratches and footpad lesions was recorded. Litter material had no effect on bird feathering. Carcass lesions (scratches, bruises and footpad lesions) were influenced by the litter material evaluated. Birds reared on sugarcane bagasse and chopped Napier grass presented more scratches, bruises and footpad lesions than the others. Dermatitis was more evident in birds reared on sugarcane bagasse, chopped Napier grass and the combination of litter materials. It was found that males presented higher incidence of dermatitis and footpad lesions than females. Each litter material presented different compaction degrees, which increased along the experimental period. Sugarcane bagasse, chopped Napier grass and the combination of bedding materials presented the highest degree of compaction, compared with wood shavings and rice husks.
Abstract in English:This study was conducted to determine the presence of enterobacteria in the eggs of ostriches reared on a farm with a history of reproductive failure. Ninety samples from twenty eggs were submitted to bacteriological tests. The results showed Enterobacteria growth in 100% of the eggs. The microorganisms isolated were Hafnia alvei in 50% (10/20), Serratia spp. in 20% (4/20), Escherichia coli in 15% (3/20), and Citrobacter freundii in 15% (3/20). All eggs presented poor eggshell quality, which favored enterobacteria contamination. Hafnia alvei was present only in the internal egg structures (albumen and yolk sac), suggesting the possibility of vertical infection.
Abstract in English:Aiming at evaluating the influence of cyclic temperatures on the performance and egg quality of Japanese quails an experiment was carried out with 480 birds after egg production peak. Birds were housed in a bioclimatic chamber with automatic temperature control that contained two rooms, one maintained at thermoneutral temperature (21 ºC) and the other adjusted for the tested cyclic temperatures (24, 27, 30, 33 and 36 ºC at a time). Each room had a battery of five floors and ten cages, with a capacity of 24 birds per cage, totaling 240 birds per battery. Birds were fed iso-nutritious and iso-caloric diets. Data obtained under the tested cyclic temperatures were compared with those obtained under thermoneutral temperature. At the end of each experimental period (14 days) performance and egg quality parameters were evaluated. A completely randomized experimental design with two treatments (thermoneutral temperature and tested temperature) and ten replicates of 24 birds each. Cyclic increases of 27 ºC and higher in environmental temperature negatively affected bird performance, with reduced feed intake and consequent reductions in egg weight and mass. A cyclic increase of the environmental temperature to 36 ºC reduced the percentage of saleable eggs and egg production.
Abstract in English:This study was conducted to test the hypothesis that proper diet dilution ratio at early age might improve feed conversion ratio (FCR) and reduce body fat deposition of meat-type ducks. One hundred and fifty 1-day-old male and female White Pekin ducks (44.5±1.0 g) were randomly assigned into three treatments with five replicates (pens) of 10 birds each, respectively representing the experimental diets with 0 (control), 40 or 60% rice hulls inclusion in the basal diet between 8 and 14 d of age. The basal diet was fed before and after this period. The results showed that diluting the diet with 40% rice hulls increased (p < 0.05) feed intake, decreased adjusted (excluding rice hulls) feed:gain and body weight gain of ducks during the diet-dilution period; ducks fed the diet with 40% rice hulls had better growth rate (p < 0.05) during the recovery period (15 to 42 d of age) and lower adjusted feed conversion ratio (p < 0.05) during the entire experimental period (1 to 42 d of age) than the control birds, but the same body weight (p > 0.05) as the controls at 42 d of age. The diet diluted with 60% rice hulls resulted in lower (p < 0.05) body weight at market age than the other treatments. The diet with 40% rice hulls reduced (p < 0.05) skin with fat and abdominal fat pad, crude fat content in the carcass and in breast meat, and increased (p < 0.05) carcass crude protein at 42 d of age. These changes may be explained by the lower (p < 0.05) activities of hepatic malic dehydrogenase (MDH), glucose-6-phosphate dehydrogenase (G-6-PDH) and fatty acid synthetase (FAS) enzymes both at 14 and 42 d of age in birds fed the diluted diets relative to the control birds. The results of this study indicate that feeding diets diluted with 40% rice hulls to Pekin ducks between 8 to 14 d of age may induce compensatory growth during the following recovery period, and may be used to improve FCR and to reduce body fat deposition at market age.
Abstract in English:The objective of this study was to verify if the dietary inclusion of sugarcane yeast at levels commonly used in broiler diets influences the traceability of cattle meat meal and poultry offal meal, using the technique of stable carbon and nitrogen isotopes in the breast muscle of chickens. A number of 325 one-d-old male broilers were randomly distributed into 13 treatments with 25 birds each. Treatments consisted of a control diet based on corn and soybean meal, and the inclusion of 1, 2, 4, or 6% meat and bone meal, poultry offal meal or sugarcane yeast. At 42 days of age, six birds per treatment were randomly selected, sacrificed, and their breast muscle was collected for isotopic ration analysis. The isotopic ratio of birds fed the diet with inclusion of 6% sugarcane yeast was different from those fed the control treatment, but not from those fed diets with the inclusion of 2, 4 and 6% meat and bone meal or 4 and 6% poultry offal meal. The inclusion of 6% sugarcane yeast in broiler diets based on corn and soybean meal may affect the traceability of animal by product meals.
Abstract in English:The relationship between sorghum grain color and tannin content was reported in several references. In this study, 33 phenotypes of sorghum grain differing in seed characteristics were collected and analyzed by Folin-Ciocalteu method. A computer image analysis method was used to determine the color characteristics of all 33 sorghum phenotypes. Two methods of multiple linear regression and artificial neural network (ANN) models were developed to describe tannin content in sorghum grain from three input parameters of color characteristics. The goodness of fit of the models was tested using R², MS error, and bias. The computer image analysis technique was a suitable method to estimate tannin through sorghum grain color strength. Therefore, the color quality of the samples was described according three color parameters: L* (lightness), a* (redness - from green to red) and b* (blueness - from blue to yellow. The developed regression and ANN models showed a strong relationship between color and tannin content of samples. The goodness of fit (in terms of R²), which corresponds to training the ANN model, showed higher accuracy of prediction of ANN compared with the equation established by the regression method (0.96 vs. 0.88). The ANN models in term of MS error showed lower residuals distribution than that of regression model (0.002 vs. 0.006). The platform of computer image analysis technique and ANN-based model may be used to estimate the tannin content of sorghum.
Abstract in English:Recent studies have reported the use of IgY antibody in the prevention or treatment of diseases in animals. IgY can be obtained in large amounts from the yolk of chicken eggs through a low-cost process. This study evaluated the effect of different routes of inoculation on antibody production and spleen morphological characteristics of laying hens (White Leghorn) inoculated with sheep red blood cells. The analysis of the results showed that the intramuscular route is the most efficient for total antibody production in the primary immune response, while the intravenous route is the most efficient in producing IgY antibodies in the secondary immune response. No histological changes were observed in the spleen of laying hens. This study could be useful for developing protocols of antigen inoculation in laying hens for IgY antibody production.