Occupational exposure to aflatoxin B1: the case of poultry and swine production

Although there is an abundance of literature concerning the ingestion of food contaminated with aflatoxin B1 (AFB1), only a small number of studies explore mycotoxin exposure in occupational settings. Taking this into consideration, our study was developed with the intention of elucidating whether there is occupational exposure to AFB1 in Portuguese poultry and swine production facilities. A specific biomarker was used to assess exposure to AFB1. A total of 45 workers (34 from poultry farms; 11 from swine production facilities) participated in this study, providing blood samples. Additionally, a control group (n=30) composed of subjects without any type of contact with agricultural activity was considered. All participants signed a consent form and were provided with the study protocol. Eighteen poultry workers (58.6%) and six workers from the swine production facilities (54.5%) showed detectable levels of AFB1. In the control group, the AFB1 values were all below 1 ng/ml. No significant differences in AFB1 levels in serum between workers from poultry and swine farms were found. Poultry workers, however, showed the highest serum levels and a significant statistical difference between this group and the control group was found. Results suggest that exposure to AFB1 by inhalation occurs in both occupational settings representing an additional risk that needs to be recognised, assessed and prevented.

Potential poultry and meat products contamination by aflatoxin B1 due to fungal presence in Portuguese poultry units

The impact of mycotoxins on human and animal health is well recognized. Aflatoxin B1 (AFB1) is by far the most prevalent and the most potent natural carcinogen and is usually the major aflatoxin produced by toxigenic fungal strains. Data available, points to an increasing frequency of poultry feed contamination by aflatoxins. Since aflatoxin residues may accumulate in body tissues, this represents a high risk to human health. Samples from commercial poultry birds have already presented detectable levels of aflatoxin in liver. A descriptive study was developed in order to assess fungal contamination by species from Aspergillus flavus complex in seven Portuguese poultry units. Air fungal contamination was studied by conventional and molecular methods. Air, litter and surfaces samples were collected. To apply molecular methods, air samples of 300L were collected using the Coriolis μ air sampler (Bertin Technologies), at 300 L/min airflow rate. For conventional methodologies, all the collected samples were incubated at 27ºC for five to seven days. Through conventional methods, Aspergillus flavus was the third fungal species (7%) most frequently found in 27 indoor air samples analysed and the most commonly isolated species (75%) in air samples containing only the Aspergillus genus...

Macrocheles muscaedomesticae (Acari, Macrochelidae) and a species of Uroseius (Acari, Polyaspididae) phoretic on Musca domestica (Diptera, Muscidae): effects on dispersal and colonization of poultry manure

Differences in the phoresy of the mites Macrocheles muscaedomesticae (Scopoli, 1972) (Macrochelidae) and Uroseius sp. (Polyaspidae) on the house fly, Musca domestica (Linnaeus, 1758) and the similarities in their phoretic dispersal and parasitism are discussed, altogether with the effects on predator-prey interactions. The prevalence and intensity of phoresy in the mite species were significantly related to the attachment site on the hosts. The phoresy of Uroseius sp. was correlated with temperature but not with rainfall and relative humidity. Selective pressure in the environment resulted in displacement and the emergence of local and regional populations. These results suggest that in each habitat the populations will use different resources and will show several relationships with other species, as well as a selection for morphological and behavioral types.

The interaction between Poultry and Triatoma infestans Klug, 1834 (Hemiptera: Reduviidae) in an experimental model

This paper compares the predation pressure that ducks and chickens exert on triatomines. For the tests, these birds were placed in individual boxes together with a known number of Triatoma infestans and left to interact from 6 p.m. till the next morning, involving a long lasting period of complete darkness limited by two short-term periods of semi-darkness. There was a shelter which could prevent the bugs from being predated. The number of live and dead triatomines was recorded, considering missing bugs as predated by the birds. Ducks exhibited a greater predatory activity than chickens, that could be due to a long term active period at night while chickens sleep motionless from sunset to dawn. Surviving triatomines that had fed on chickens outnumbered those fed on ducks suggesting that these were less accessible to the triatomine biting. If ducks are better than chickens to detect and eat bugs and to interfere with their feeding in the field, an increase in duck number might help to diminish triatomine density. Further research is needed to determine the feasibility of application of these experimental results.

Age structure and abundance in populations of muscoid flies from a poultry facility in Southeast Brazil

Muscina stabulans, M. domestica, Chrysomya putoria, C. megacephala and Stomoxys calcitrans were the most abundant muscoid flies captured in a poultry facility in southeastern Brazil. We examined the gonadotrophic profiles of the females caught at different sites and different times and found that Mu. stabulans and M. domestica, the predominant species, presented similar gonadotrophic profiles only when captured on the manure under the cages, but very different and sometimes opposite gonadotrophic profiles when sampled from wooden posts, vegetation or electric cords. We also determined sex ratios and relative abundance for these two species and found significant differences between them. More than 50% of the females of both species of Chrysomya captured on manure carried eggs or exhibited signs of recent oviposition. The vast majority of S. calcitrans presented ovaries with eggs or signs of recent oviposition. A small proportion of them had ovaries in the recent emerged condition. Our data on ovarian stages, sex ratio and relative abundance allowed us to associate different gonadotrophic profiles with each site and characterize each site as a resting, ovipositing or mating site.

Antimicrobial resistance profiles of enterococci isolated from poultry meat and pasteurized milk in Rio de Janeiro, Brazil

The enterococci are important nosocomial pathogens with a remarkable capacity of expressing resistance to several antimicrobial agents. Their ubiquitous nature and resistance to adverse environmental conditions take account for their ability to colonize different habitats and for their potential for easy spreading through the food chain. In the present study we evaluated the distribution of species and antimicrobial susceptibility among enterococcal isolates recovered from food obtained in retail stores in Rio de Janeiro, Brazil. The following species were identified among 167 isolates obtained from poultry meat and 127 from pasteurized milk: Enterococcus faecalis (62.6%), E. casseliflavus (17.3%), E. durans (6.5%), E. gallinarum (3.0%), E. gilvus (2.4%), E. faecium (2.0%), E. hirae (1.4%), and E. sulfureus (1.0%). The overall percentages of antimicrobial resistant isolates were: 31.2 % to tetracycline, 23.8% to erythromycin, 11.3% to streptomycin, 4.3% to chloramphenicol, 3.9% to gentamicin, 1.4% to norfloxacin, 1.1% to imipenem, 0.7% to ciprofloxacin, nitrofurantoin, and penicillin, and 0.4% to ampicillin. Intermediate resistance was detected in frequencies varying from 0.5% for linezolid to 58.2% for erythromycin. None of the isolates showed resistance to glycopeptides. High-level resistance to aminoglycosides was observed in 13.1% of the isolates. Multiresistance was observed in E. faecalis, E. casseliflavus, E. faecium, E. gallinarum, E. durans and E. gilvus.

Year-round poultry litter decomposition and N, P, K and Ca release

Poultry litter is an important nutrient source in agriculture, although little information is available regarding its decomposition rate and nutrient release. To evaluate these processes, poultry litter (PL) was applied to the soil to supply 100, 200 and 300 kg ha-1 N contained in 4,953, 9,907 and 14,860 kg ha-1 PL, respectively. The litter bag technique was used to monitor the process of decomposition and nutrient release from the litter. These bags were left on the soil surface and collected periodically (after 15, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, and 365 days). The dry matter (DM) loss was highest (35 %) after the first 30 days of field incubation. The highest nutrient release occurred in the first 60 days on the field, when 40, 34, 91, and 39 %, respectively, of N, P, K, and Ca of the initial PL dry matter (4,860 kg ha-1) was already released to the soil. In absolute terms, these percentages represent 40, 23, 134, and 69 kg ha-1 of N, P, K, and Ca and these values doubled and tripled as the PL fertilization rates increased to 9,907 and 14,860 kg ha-1, respectively. After one year of field incubation, the residual contents in the litter were 27, 15, 18 and 30 % of the initial DM , and N, P and Ca, respectively. The release rate of K was the fastest and 91 % of the K had been released from the PL after 30 days of field incubation.

Phosphorus transformation in poultry litter and litter-treated Oxisol of Brazil assessed by 31P-NMR and wet chemical fractionation

Large quantities of poultry litter are being produced in Brazil, which contain appreciable amounts of phosphorus (P) that could be of environmental concern. To assess the immediate environmental threat, five poultry litters composed of diverse bedding material were incubated for 43 days under greenhouse conditions. The litters consisted of: coffee bean husk (CH); wood chips (WC); rice husk (RH); ground corn cobs (CC) and ground napier grass (NG) (Pennisetum purpureum Schum.), in which the change in forms of soluble P was evaluated using 31P NMR spectroscopy. On average, 80.2 and 19.8 % of the total P in the extract, respectively, accounted for the inorganic and organic forms before incubation and 48 % of the organic P was mineralized to inorganic P in 43 days of incubation. Wide variation in the organic P mineralization rate (from 82 % -WC to 4 % - NG) was observed among litters. Inorganic orthophosphate (99.9 %) and pyrophosphate (0.1 %) were the only inorganic P forms, whereas the organic P forms orthophosphate monoesters (76.3 %) and diester (23.7 %) were detected. Diester P compounds were mineralized almost completely in all litters, except in the CH litter, within the incubation period. Pyrophosphates contributed with less than 0.5% and remained unaltered during the incubation period. Wood-chip litter had a higher organic P (40 %) content and a higher diester: monoester ratio; it was therefore mineralized rapidly, within the first 15 days, achieving steady state by the 29th day. Distinct mineralization patterns were observed in the litter when incubated with a clayey Oxisol. The substantial decrease observed in the organic P fraction (Po) of the litter types followed the order: CH (45 %) > CC (25 %) > RH (13 %) ≈ NG (12 %) > WC (5 %), whereas the Pi fraction increased. Incubation of RH litter in soil slowed down the mineralization of organic P.

Official positions of the International Society for Clinical Densitometry (ISCD) on DXA evaluation in children and adolescents.

Dual-energy X-ray absorptiometry (DXA) is the most widely used technical instrument for evaluating bone mineral content (BMC) and density (BMD) in patients of all ages. However, its use in pediatric patients, during growth and development, poses a much more complex problem in terms of both the technical aspects and the interpretation of the results. For the adults population, there is a well-defined term of reference: the peak value of BMD attained by young healthy subjects at the end of skeletal growth. During childhood and adolescence, the comparison can be made only with healthy subjects of the same age, sex and ethnicity, but the situation is compounded by the wide individual variation in the process of skeletal growth (pubertal development, hormone action, body size and bone size). The International Society for Clinical Densitometry (ISCD) organized a Pediatric Position Development Conference to discuss the specific problems of bone densitometry in growing subjects (9-19 years of age) and to provide essential recommendations for its clinical use.

Poultry carcass decomposition and physicochemical analysis of compounds in different Composter types

This study aimed to assess five composter types in poultry carcasses decomposition and to perform a physicochemical analysis of the compounds obtained. Composter types used were six-hole brick, wood, screen, windrow with three PVC pipes with six holes and windrow with three PVC pipes with 10 holes. Composting was followed by four periods using wood shaving like substrate with one bird carcass placed in each composter. Pile turning was performed every 10 days and temperature in each layer was measured on 1st, 7th, 14th, 19th and 29th day, at 3 p.m., as well as room temperature. Temperature during pile turning was also measured at five points per layer and carcass weighing performed to calculate decomposition percentage. Physicochemical parameters evaluated in substrates were moisture, ash, phosphorus, potassium, nitrogen, pH, organic carbon and C/N ratio, up to 30 days. Data were analyzed by repeated measures model, using MIXED method of SAS software. All values of final physicochemical composition of substrates were found according to values of IN-25, except nitrogen. The composter types were efficient in decomposition of poultry carcasses.

Environment in poultry production covered with thermal and aluminum roofing tiles

Brazil is a country of tropical climate, a fact that hinders the poultry production in the aspect of thermal comfort. Thus, we aimed to evaluate the thermal environment in commercial poultry houses with different covers during the months of December 2012 to May 2013, in the municipality of Rio Verde, Goiás. The experimental design was completely randomized in split plots with factorial arrangement of treatments 2x3, being two shed models (thermal and aluminum roof tiles) and three sections within each shed (initial, central and final) for 182 days, having the days as replicates. The thermal environment was assessed through thermal comfort indices: Temperature and Humidity Index, Black Globe Temperature and Humidity Index, Radiant Heat Load and Enthalpy. The data was analyzed by SISVAR 5.1., through the analysis of variance, the Scott Knott test used to compare the means, considering a significance level of 1%. The results showed a significant statistical difference between the sheds and the points assessed (P < 0.05). The thermal shed had the lowest values for the environmental variables (Dbt and Bgt) and thermal indices studied, but larger values for the RH compared to the shed with aluminum covering. The use of thermal covers minimizes the difference in temperature range throughout various times of the day, being at 14:00 o'clock the prominence time to others.

Effect of cycle time and airflow in biological nitrogen removal from poultry slaughterhouse wastewater using sequencing batch reactor

This study aimed to evaluate the influence of airflow (0.25, 0.50 and 0.75 L.L-1.min-1) and cycle time (10.45 h, 14.25 h and 17.35 h) on a sequencing batch reactor (SBR) performance in promoting nitrification and denitrification of poultry slaughterhouse wastewater. The operational stages included feeding, aerobic and anoxic reactions, sedimentation and discharge. SBR was operated in a laboratory scale with a working volume of 4 L, keeping 25% of biomass retained inside the reactor as inoculum for the next batch. In the anoxic stage, C: N ratio was maintained between 5 and 6 by adding cassava starch wastewater. A factorial design (22) with five repetitions was designed at the central point to evaluate the influence of cycle time and airflow on total inorganic nitrogen removal (N-NH4++N-NO2-+N-NO3-) and in the whole process (nitrification and denitrification). The highest total inorganic nitrogen removal (93.3%) was observed for airflow of 0.25 L.L-1.min‑1 and a cycle time of 14.25 h. At the end of the experiment, the sludge inside the reactor was characterized by fluorescent in situ hybridization (FISH), indicating the presence of ammonia and nitrite oxidizing bacteria.

Energy balance in the poultry-shed system and its influence on broiler performance

ABSTRACTThe objective of this study was to determine the energy balance of the poultry-shed system and its effect on broiler performance during the production cycle. The experimental design was completely random with sub-divided blocks. The blocks were composed of five different types of sheds and the sub-blocks of the evaluation times (00:00 h to 23:00 h), allowing an analysis of variance and a comparison between means with the Tukey test. There were no significant differences between the mean values of the exchanges of sensible, latent and total heat between the poultry sheds but the differences for the evaluation times were significant (P<0.05). There was no significant difference between sheds 1 and 4 for broiler productive performance regarding weight gain, feed consumption and feed conversion. Bird performance was significant (P<0.05) for the remaining poultry sheds. The productive indexes remained below the ranges considered ideal for broilers and values in the final weeks were characterized by the poor installation efficiency in controlling temperature variations and, consequently, the energy balance in the system, which adversely affected bird productive performance.

Epidemiological survey on Mycoplasma gallisepticum and M. synoviae by multiplex PCR in commercial poultry

Mycoplasmas are important avian pathogens, which cause respiratory and joint diseases that result in large economic losses in Brazilian and world-wide poultry industry. This investigation regarding the main species of mycoplasmas, Mycoplasma gallisepticum (MG) and M. synoviae (MS), responsible for the above mentioned conditions, was carried out through PCR Multiplex analysis. One thousand and forty-six (1,046) samples of tracheal swabs and piped embryos were collected from 33 farms with laying hens, breeders, broilers or hatchery, located in the Brazilian states of São Paulo, Paraná and Pernambuco, where respiratory problems or drops in egg production had occurred. The MG and MS prevalence on the farms was 72.7%. These results indicated (1) high dissemination of mycoplasmas in the evaluated farms, with predominance of MS, either as single infectious agent or associated with other mycoplasmas in 20 farms (60.6%), and (2) an increase of MS and decrease of MG infection in Brazilian commercial poultry.