Abstract in English:
The objective of this study was to investigate the prevalence of health related symptoms and to analyze the work activities of workers in contracted non-mechanized broiler farms in two regions of the state of Paraná in order to determine possible factors associated to those symptoms. The methods consisted in selecting the houses and the workers, and to apply a questionnaire that included demographic data, questions related to work, the Nordic Questionnaire for Musculoskeletal Symptoms, other symptoms (runny nose, skin itching, throat and eye irritation). In addition, workers were asked if they enjoyed their job, if the supervisor motivated them to work, and if they were afraid to lose their job. Activities were submitted to systematic observations, adapted from Ergonomics, and the loads carried were analyzed and some instruments weighted. The study included 80 workers of both genders between 16 and 59 years, being 40 from each region. There were evidences of low back pain risk in the activities of filling drinkers and washing bell drinkers, with a higher prevalence in region A, where automated systems were less frequently used. The study suggests that mechanized filling of feeders, and the use of nipple drinkers may prevent health problems. It was also found that psychosocial aspects were associated to musculoskeletal symptoms. Promoting better working conditions is essential, as these aspects can affect human behavior at work.Abstract in English:
A 112-day trial was carried out to evaluate the effect of dietary calcium level and limestone particle size on the egg quality of 288 Hy-Line Brown semi-heavy layers, with 83 weeks of age at the beginning of the experiment. A completely randomized experimental design was applied in a 2x3 factorial arrangement, with two dietary calcium levels (3.5 and 4.0%) e three limestone particle size compositions (100% fine limestone (FL), with 0.185mm; 30% coarse limestone (CL), with 2.83mm, + 70% FL, with 0.185mm; and 50% CL, with 2.83mm, + 50% FL, with 0.185mm), with six replicates of eight birds each. Mean geometric diameter and in-vitro solubility of the limestone sources were, respectively, 0.185mm and 18.7% for the fine limestone, and 2.83mm and 10.5% for the coarse limestone. At the end of each 28-day period, 72 eggs per treatment were used to determine egg specific gravity, yolk percentage, albumen percentage, eggshell percentage, yolk index, Haugh units, eggshell thickness, and eggshell breaking strength. There was no influence of the treatments on the evaluated parameters. It was concluded that feeding the level of 3.5% calcium usually recommended for layers in their first laying cycle, and the substitution of up to 50% fine limestone by coarse limestone in the feed of semi-heavy commercial Hy-Line Brown layers in their second laying cycle can be applied with no impairment of egg quality.Abstract in English:
This study evaluated the effect of dietary calcium levels and limestone particle size distribution on first-cycle layer performance and egg quality. A completely randomized experimental design in 4x3 factorial arrangement (four Ca levels - 3.0, 3.5, 4.0, 4.5%; and three limestone particle size distributions - 100% fine, 50% fine and 50% coarse, 30% fine and 70% coarse) was applied, totaling 12 treatments with six replicates of eight birds each. The treatments did not influence the most of evaluated performance and internal and external egg quality parameters. However, limestone particle size distribution quadratically affected with percentage of defective eggs, with the lowest percentage obtained with the distribution 61.75% fine limestone and 38.25% coarse limestone. Increasing dietary Ca levels significantly increased eggshell weight per surface area and the percentage of Ca excreted in the feces. It was concluded that the combination of the highest dietary Ca level (4.5%) with 50% replacement of fine-particle limestone by coarse limestone results in better eggshell and increases the number of marketable eggs.Abstract in English:
Lutein supplements are often used to pigment and enrich layer chicken eggs. This experiment was conduced to compare the bioavailability of free and esterified lutein, by depletion method. Forty chickens were randomly divided into two groups. After 2 weeks of washout period, when all birds were fed the same low lutein basal diet, the two groups were fed for another 2 weeks with diets supplemented with free lutein or esterified lutein. Two experimental diets were supplemented with the same amount of 15 mg lutein/kg. On day 0 (baseline) and days 3, 7, and 14, birds fasting morning plasma samples were collected and stored for lutein analysis by high performance liquid chromatography method (HPLC). Results showed that: 1) Plasma lutein concentration increased dramatically after feeding free or esterified lutein; 2) Plasma lutein level in birds fed the diet supplemented with free lutein significantly differed from those fed esterified lutein on day 3. 3) There were no significant differences in plasma lutein levels between free lutein and esterified lutein on days 7 and 14. In conclusion, the lutein bioavailability from free lutein or esterified lutein supplements was comparable.Abstract in English:
An experiment was carried out to evaluate the effects of different levels of digestible lysine in the diets of male and female broilers on protein and fat deposition. A total of 2160 Avian Farms broilers. A completely randomized experimental design was applied, and treatments consisted of the effects of three digestible lysine levels nested within each sex, with 12 replicates and 30 birds per experimental unit. The adopted digestible lysine levels corresponded to 92.5, 100.0, and 107.5% of the nutritional requirements of phases 1 to 21 days, 22 to 42 days, and 43 to 56 days of age, respectively. In each phase, the experimental diets contained similar calorie and protein levels within each sex. No significant effects of lysine levels were found on dry matter and fat percentages in the carcass of birds during the evaluated periods. Also, there were no significant effects of lysine levels on protein and fat deposition in males or females. However, males presented higher protein deposition and lower fat deposition than females during the total experimental period. Gompertz equations showed that females deposit more fat and less protein than males, and that this affected the fall in the curve of protein deposition, when the curve of fat deposition was still rising. Therefore, it was concluded that the older the broilers at slaughter, the higher their body fat content and the lower their body protein content, particularly in females.Abstract in English:
This study aimed at studying alternative methods to induce molting and to compare them with the conventional forced-molting method (fasting). In the experiment, 420 70-week-old layers were used. The total experimental period was 140 days. Molting was induced during the first 28 days, when birds were submitted to the experimental treatments, and bird performance and egg quality parameters were determined during 112 subsequent days. A completely randomized experimental design was applied in a 5x2 factorial arrangement of five feed restriction regimes (0, 15, 30, 45, or 60g feed/bird/day) and with or without the addition of coarse-particle limestone to the feed, with seven replicates of six birds each. Egg quality was evaluated at the end of each 28-day period for three consecutive days, using three eggs per experimental unit (21 eggs/treatment), with a total of 210 eggs. It was concluded that feeding 15g feed/bird/day to induce molting is feasible, as birds submitted to this treatment presented similar performance and better egg quality than those submitted to fasting during molting. The use of coarse-particle limestone during molting did not influence post-molting bird performance or egg quality.Abstract in English:
This paper describes the identification of an outbreak of fowlpox in backyard chickens in two villages the state of Bahia, the intervention strategy to control the disease by adopting health measures and vaccination, as well as the impact of the intervention. The diagnosis was based in clinical and laboratory data. After the diagnosis was confirmed, control measures and the vaccination of non-infected birds were recommended. Finally, the impact of the intervention on re-incidence of the disease was evaluated. A number of 700 chickens was vaccinated, after which only 9% of the farmers reported the occurrence of new cases, and 70% informed the acquisition of new birds after vaccination. The information reported in this paper can be useful to design strategic plans to control fowlpox in backyard chickens.Abstract in English:
The beetle Alphitobius diaperinus (Panzer), considered a worldwide pest in the poultry industry, is difficult to control and it is a vector for pathogens. The objective of this study was to evaluate the biological control of the lesser mealworm, by strains of fungi Beauveria bassiana, Cladosporium sp. and Trichoderma sp. Larvae and adults of the A. diaperinus were inoculated with suspensions of conidia in the concentration of 10(7) conídia.mL-1. The B. bassiana isolate caused higher insect mortality as compared to Cladosporium sp. and Trichoderma sp. isolates, with the larvae being more susceptible than adults. The entomopathogenicity of B. bassiana was further evaluated with 200 larvae and 200 adults of A. diaperinus inoculated with suspensions 10(6), 10(7), and 10(8) conidia.mL-1, and observed for ten days. Larvae mortality started at the fourth day at the lowest concentration, and the adult mortality was only observed on the sixth day at the concentration of 10(8) conidia.mL-1.Abstract in English:
Intracerebral pathogenicity index (ICPI) and mean death time (MDT) were determined using commercial live vaccines against Newcastle disease available in Brazil. The ICPI profiles obtained for B1 vaccine strains were nonvirulent and varied from 0 to 0.19, and their MDT was 104-116 hours. The LaSota strains had an ICPI varying between 0.02 and 0.37 and MDT from 92 to 116 hours. ICPI and MDT for the Clone 30 were 0.11 and 104 hours, respectively. For Ulster vaccines, ICPI and MDT were 0 and >150 hours; for VG-GA was 0.03 and 140 hours; and for C2, 0.04 and >144 hours. Eye drop vaccination and IM challenge, at the 1st week and the 4th week, respectively, resulted in highest protection for B1 (95-100%) and LaSota (90-100%) strains. The variability in vaccine ICPI did not interfere with immune response and all vaccines provided similar protection. All vaccines were considered non virulent and were classified as lentogenic according to the immunobiological product standards.Abstract in English:
The occurrence of CAV in backyard chickens in the metropolitan area of Belo Horizonte, Brazil, was evaluated. The spleen and thymus of chickens from different origins were collected for DNA extraction and nested-PCR. CAV genome was detected in 30% of the flocks (n=20) examined. CAV origin for backyard chickens is speculated, taking into consideration its widespread incidence in the chicken industry, the contamination of live vaccines with CAV prior to its eradication from SPF flocks, and the use of attenuated CAV vaccines.