Resumo em Inglês:

ABSTRACT Barn and cage-fed chickens have presented several problems, such as high rates of infectious disease and consequent antibiotic abuse, poorer chicken health and welfare, and often poorer meat and egg quality compared with free-range chickens. The poultry agroforestry system is becoming increasingly popular in many poultry farms nowadays. In this study, to evaluate the contribution of poultry agroforestry system to enhance some meat and egg traits of Beijing-you chickens, some indexes of meat and egg qualities, some indexes of slaughter traits, and the feed conversion efficiency were investigated in rotational grazing Beijing-you chickens on chicory (Cichorium intybus L.) pasture (CGRG group) and only free-ranging chickens on bare land without forage (control group) in chestnut forest. Results showed that the live body weight, the dressing weight, the thigh muscle weight, and the breast muscle weight were increased (p<0.05) based on the decrease of 15% feed concentration in the CGRG group relative to the control. Furthermore, compared with the control, the crude ash, the essential amino acid content, and the inosinic acid content were increased (p<0.05), and the crude fat contents were decreased (p<0.05) in the thigh and breast muscles, while the yolk cholesterol and the feed conversion ratio were significantly decreased (p<0.05) in the CGRG group. This study would provide a scientific basis and technological support for the large-scale demonstration and application of rotational grazing chickens on the artificial pasture in forest.

Resumo em Inglês:

ABSTRACT Bovine meat and bone meal (MBM) has been used as a low-cost protein source in corn- and soybean meal-based poultry diets. However, to date, no studies investigating the effect of the dietary inclusion of MBM on the performance of Japanese quails and on egg production costs were found in literature. In this study, 600 Japanese quails in lay were distributed in a completely randomized experimental design consisting of six treatments (replacement levels of soybean meal by MBM:0, 1, 2, 3, 4, and 5%) with five replicates of 20 birds each to investigate if MBM is a viable alternative to maintain or to improve the live and economic performances of these birds. Treatments consisted of a control diet, based on corn and soybean meal, with no inclusion of MBM, and diets formulated with increasing levels (1, 2, 3, 4, and 5%) of MBM inclusion at the expense of soybean meal. The studied parameters were evaluated in four periods of 28 days each. Live performance parameters (egg weight, g; average egg production, %; egg weight, g; feed intake, g; feed conversion ratio per egg mass, kg/kg and per dozen eggs, dz/kg; and livability, %); egg quality parameters (proportion of egg components, yolk, albumen, eggshell %; egg specific weight, g/cm3); and economic parameter (bio-economic nutritional index) were determined. Only egg weight, egg specific weight, and eggshell percentage were affected (p<0.05) by the treatments. Our results show that inclusion of bovine meat and bone meal can be added to the diet of Japanese quails in lay, causing no performance losses and promoting feed cost savings up to 5.24%.

Resumo em Inglês:

ABSTRACT Incubation is an important factor in poultry production, particularly in species with relatively low fertility and hatchability rates. This study examined the effect of eggshell thickness on hatching traits of partridges (A. chukar). A total of 462 eggs from intensively reared partridges were separated into three groups according to eggshell thickness, which was measured ultrasonically before incubation. Hatchability, chick weight, and chick length were assessed at the end of the incubation period. Hatching times were recorded during hatching. Embryonic mortalities in unhatched eggs were classified according to mortality stage at the end of incubation. The effect of eggshell thickness on hatchability was found to be insignificant for all groups. Moreover, eggshell thickness had no significant effect on chick weight or length.

Resumo em Inglês:

ABSTRACT This paper discusses the Bayesian approach as an alternative to the classical analysis of nonlinear models for growth curve data in Japanese quail. A Bayesian nonlinear modeling method is introduced and compared with the classical nonlinear least squares (NLS) method using three non-linear models that are widely used in modeling the growth data of poultry. The Gompertz, Richards and Logistic models were fitted to 499 Japanese quail weekly averaged body weight data. Normal prior was assumed for all growth curve parameters of the models with assuming Jeffreys' non-informative prior for residual variances. Models were compared based on the Bayesian measure of fit, deviance information criterion (DIC), and our results indicated the better fit of Gompertz and Richards models than the Logistic model to our data. Moreover, the parameter estimates of the models fitted by both approaches showed only small differences.

Resumo em Inglês:

ABSTRACT Aiming at accelerating the application of molecular markers in the genetic improvement of quails, six EST-SSR markers were successfully developed using a bioinformatics method. Polymorphisms of three quail populations (Chinese yellow quail, China black quail and Korean quail) were detected. The results showed that there were 2-6 alleles in six EST-SSR markers. Mean polymorphism information contents of Chinese yellow quails, Chinese black quails and Korean quails were determined as 0.5451, 0.4962 and 0.4937, respectively. Average heterozygosity valuesof 0.6134, 0.5759 and 0.5613 were calculated. Among the six EST-SSR markers, three were highly polymorphic, and the other three were moderately polymorphic. The newly-developed six EST-SSR markers may be used to determine the genetic diversity of quails. The six EST-SSR markers identified were related to carbohydrate metabolism and melanin synthesis, but their specific mechanisms need to be further analyzed.

Resumo em Inglês:

ABSTRACT Calcium (Ca) and available phosphorus (avP) requirements for egg production are different between the beginning and the end of the egg-production cycle. The objective of this study was to estimate the Ca and avP requirements of Japanese quails at end of the production phase. In total, 256 Japanese quails with 48 weeks of age were randomly distributed in 2 x 2 factorial arrangement consisting of two Ca levels (29 and 38 g/kg) and two avP levels (1.5 and 3.0 g/kg), totaling four treatments with eight replicates of eight hens each. The variables evaluated were feed intake (FI); egg production (EP); marketable egg production (MEP); egg weight (EW); egg mass (EM); feed conversion ratio per egg mass (FCRM); feed conversion ratio per dozen eggs (FCRD); livability (L); yolk weight (YW), albumen weight (AW), eggshell weight (SW); yolk percentage (YP), albumen percentage (AP), eggshell percentage (SP), specific egg weight (SEW); bone calcium percentage (BCa), bone phosphorus percentage (BP), bone ash weight (Bash) and bone ash percentage (PBash). There was no interaction between Ca and avP levels for any of the evaluated parameters, except for SEW. Quail performance was not influenced by the treatments, except for MEP. Bone characteristics were not influenced by the tested dietary Ca and avP levels. However, SW and SP increased and AP decreased as dietary Ca level increased. The dietary supplementation of 38 g Ca/kg and 3.0 g avP/kg may increase marketable egg production and the egg quality of Japanese quails at end of the production cycle.

Resumo em Inglês:

ABSTRACT The study aimed at evaluating the effect of litter substrates on the performance, carcass traits, and environmental comfort of red-winged tinamou (Rhynchotus rufescens). In this experiment, 160 birds, with 100 and 300 days of age, were housed into 20 pens, and distributed according to a completely randomized experimental design into five treatments with four replicates of eight birds each. Treatments consisted of five litter substrates: wood shavings, rice husks, peanut hulls, grass hay, or sand. Feed intake; weight gain; breast, hock, and footpad lesions; back feathering; total meat production; carcass and parts yield; and leukocyte counts were evaluated. Litter substrates were analyzed for dry matter content, standard microbial count, ammonia volatilization potential, water content, water holding capacity, temperature, and radiant heat load. The results showed that litter substrate did not influence the evaluated bird parameters, despite the higher microbial counts and released ammonia values determined in peanut hulls and sand, respectively. Sand also tended to have higher average temperature than the other litter substrates. It was concluded that litter substrate should be chosen at farmer discretion, taking into consideration its cost and utilization after use.

Resumo em Inglês:

ABSTRACT Time of exposure and light intensity rearing house may affect the performance and egg quality of laying quails. This research aimed at evaluating the live performance, egg quality, biometry of the reproductive system, and the gastrointestinal tract of Japanese quails (Coturnix coturnix japonica) exposed to artificial light-emitting diodes (LED) of different colors in comparison with fluorescent lamps. A total of 240 Japanese quails were distributed in completely randomized experimental design with four treatments (fluorescent lamp, and green, red, or blue LED lamps) with six replicates of 10 birds each. Average egg weight and eggshell thickness were different (p<0.05) when LED bulbs were compared with fluorescent lamps. The egg weight of the birds exposed to the red LED was similar to those under a fluorescent lamp (p>0.05). The oviduct of 64-d-old hens exposed to green LED lighting was shorter (p<0.05) than those exposed to the fluorescent lamp. Red LED can be used to replace the fluorescent lamps, as they promote the same live performance, egg quality, and morphological development of the reproductive tract of laying Japanese quails.

Resumo em Inglês:

ABSTRACT The objective of this study was evaluated the villus integrity of commercial turkeys submitted to coccidiosis prevention methods and challenged with Eimeria field oocysts, using scanning electron microscopy. Sixty BUT 9 female commercial turkeys were distributed in a completely randomized block design split with two treatments: T1- control diet without vaccinations against coccidiosis and anticoccidial drug, and T2- vaccinated against coccidiosis (commercial vaccine). On d 21 of life, all birds of all treatments were challenged with a mixed-species containing E. meleagrimitis and E. galopavonis, via crop intubation with 1 mL of ~20,000 sporulated oocysts/bird. The size of the inoculum was determined in previous experiments. At 27 and 70 days of age, five birds per treatment were randomly removed to evaluate the intestinal integrity. Duodenum, jejunum and ileum segments were collected and processed according to routine scanning electron microscope. The enteric mucosa integrity of the commercial turkeys subjected to coccidiosis vaccination was reduced when compared to the birds of the control treatment. There was no difference in the performance results, therefore these results cannot be attributed to the vaccination as well as to the ineffectiveness against the challenge that was administered.

Resumo em Inglês:

ABSTRACT The objective of this study was to determine the effects of eggshell color of guinea fowl (Numida meleagris) eggs on eggshell quality and hatchery results. The highest mean grey value (MGV), integrated density (ID), lightness (L*) and Hue angle (H*) values were obtained in eggs with lighter eggshell color. The effects of color difference (DE*) value levels on egg characteristics were evaluated. Eggshell color presented different (p<0.01) MGV, ID, L*, redness (a*), yellowness (b*), H* and Chroma (C*) values. Eggs with lighter color presented thicker eggshells and lower egg weight loss on day 25 of incubation (p<0.05) compared with intermediate and darker eggs. Eggshell color did not have any significant effect on fertility and hatchability (p>0.05). In conclusion, under the conditions of the present study, eggshell color influenced eggshell thickness and weight loss, but not hatching parameters of guinea fowl eggs. Further studies on this subject should be carried out.