Irenilza de Alencar Nääs

Selecting appropriate bedding to reduce locomotion problems in broilers

Two experiments were carried out at the Poultry Sector of the School of Agrarian Sciences of the Federal University of Grande Dourados to evaluate the incidence of leg problems in broilers reared on two distinct types of bedding material: rice husks or wood shavings, both new and reused. In both trials, a randomized experimental design was applied in factorial arrangement (2 x 2 x 2) using two genetic strains (Cobb® or Ross®); two sexes (male or female), and two litter materials (rice husks or wood shavings). In each trial 1080 one day pullets were reared equally divided in the treatments. The birds were placed in 4.5 m2 boxes at a density of 10 birds m-2. All birds were fed diets with equal nutritional density, and water was offered ad libitum. Feeds were divided in three phases: starter diet (1 - 21 days), grower diet (22 - 35 days), and finisher diet (36 - 45 days). On day 45, fifty birds were randomly selected in each experiment to evaluate flock leg problems. The following parameters were analyzed: gait score, incidence of valgus and varus disorder, footpad dermatitis, femoral degeneration, tibial dyschondroplasia, and spondylolisthesis. Ambient temperature during rearing and litter caking and moisture content were recorded in four boxes per treatment. The analytical hierarchy process was used to organize the data into specific criteria. Several criteria, related to the attributes that were determinant according to the statistical analysis, were chosen in order to provide the best input to the process. Results indicated that new wood-shavings bedding was the most appropriate bedding to prevent locomotion problems, followed by new rice husks, reused wood shavings, and reused rice husks. However, when leg problems were associated to sex and genetic strain, male Ross birds strain presented less problems when reared on new rice husks, followed by new wood shavings

The use of light-emitting diodes (LED) in commercial layer production

Artificial lighting is one of the most powerful management tools available to commercial layer producers. Artificial light allows anticipating or delaying the beginning of lay, improving egg production, and optimizing feed efficiency. This study aimed at comparing the performance of commercial layers submitted to lighting using different LED colors or conventional incandescent lamps. The study was carried out in a layer house divided in isolated environments in order to prevent any influenced from the neighboring treatments. In total, 360 Isa Brown layers, with an initial age of 56 weeks, were used. The following light sources were used: blue LED, yellow LED, green LED, red LED, white LED, and 40W incandescent light. Birds in all treatment were submitted to a 17-h continuous lighting program, and were fed a corn and soybean meal-based diet. A completely randomized experimental design with subplots was applied, with 24 treatments (six light sources and four periods) of three replicates. Egg production (%) was significantly different (p 0.05) by light source. It was concluded that the replacement of incandescent light bulbs by white and red LEDs does not cause any negative effect on the egg production of commercial layers.

Propriedades físicas e sensoriais da carne suína PSE

The work was carried out to evaluate the physical and sensory characteristics of PSE pork, their correlations and damages caused to the industry because of its occurrence. In a commercial slaughterhouse has measured the pH of carcasses (n = 1601) at 45 minutes post mortem (pH45), classified them into PSE (pH45 < 5.8) or normal (pH45 5.8). After 24 hours of cooling were collected the samples from the Longissimus dorsi muscle of the 26 normal and 26 PSE carcasses that were evaluated for color (L*, a*, b*), exudate loss, cooking loss, shear force, sensory attributes (tenderness, juiciness and flavor) and centesimal composition. Were evaluated the correlations between the physical and sensory parameters. The final pH, cooking loss, shear force and centesimal composition did not differ between the types of meat. The exudate loss was 39% higher for the PSE meat. The pH45 was negatively correlated with L* (R= -0.331) and b* (R = -0.528). The juiciness was positively correlated with flavor (r = 0.436) and tenderness (R = 0.297) and negatively with cooking loss (R = -0.326). The shear force was positively correlated with exudate loss (R = 0.529) and negatively with tenderness (R = -0.767). The estimated loss due to the occurrence of PSE meat were of R

Impact of global warming on Brazilian beef production.

340,800.00 per year. The PSE meat show negative changes in the functional and sensory properties, almost all related to reducing its water holding capacity, causing considerable losses to the processing industry.

Implications of the use of sorghum in broiler production

According to the Intergovernmental Panel on Climate Change (IPCC), in the next hundred years the average temperature may increase by 5 oC in most Brazilian regions. Global climate changes may influence the way pasture is produced, leading most of the herd to change from pasture to either confinement or semi-confinement, which significantly increases the cost of meat production. This research aims at developing a predictive function by using quantitative predictive techniques in order to estimate the loss in Brazilian cattle meat production under the IPCC forecast scenario for global warming. The fuzzy model was developed having as input variables the following historical data about environmental factors for the most important producing counties in the Cerrado: total rain index (mm); environmental temperature (oC); extension of the dry season (days). The output was the risk of decreasing the grazing land capacity (RP). As a result of RP fuzzy model, an algorithm was developed to predict the impact of the IPCC forecast scenario in order to describe the risk of drought in pasture. The results of this research pointed that the increase of 5 oC may lead to decrease in pasture capacity around 50%. According to the built scenario of global warming, environmental techniques for mitigating exposure to higher temperatures will be needed, and the cost of production will proportionally rise.

Selecting the most adequate bedding material for broiler production in Brazil

This study aimed at evaluating total or partial replacement of corn by sorghum in broiler diets and at estimating the effect of the pigment supplementation on broiler performance, carcass and cuts yield, and possible breast and leg pigmentation. We used 1680 one-d-old Ross® 308 broilers. Birds were sexed and distributed according to a completely randomized design (2 x 3 + 1). Treatments consisted of a control diet based on corn and diets with two levels corn replacement by sorghum (50 and 100%) and three pigments levels, with four replicates of 60 birds per treatment. There was no effect (p > 0.05) of the dietary replacement of corn by sorghum on performance, carcass and parts yield, and no changes in breast and leg meat pH (p >0.05). Meat redness (a*), yellowness (b*) and luminosity (L*) increased (p < 0.05) as pigment inclusion levels increased. It was concluded that the use of sorghum instead of corn did not affect broiler performance or carcass and cuts yield. When adequate pigments were used, meat color significantly improved.

Effect of the litter material on drinking water quality in broiler production

Broiler chicken production is widely dispersed across the globe, and one important issue for growers is the selection of adequate bedding material, as the availability and price of substrates varies among countries and regions within a same country. This study aimed at applying a multiple criteria analysis approach for the selection of the most appropriate bedding material for broiler production. Based on field research data and growers’ experience, the most desirable characteristics of a litter material were chosen as the main criteria. The selected materials were wood shavings, rice husks, chopped Napier grass (Pennisetum pupureum), 50% sugar cane bagasse (Saccharum L.) plus 50% wood shavings, 50% sugar cane bagasse (Saccharum L.) plus 50% rice husks, and pure sugar cane bagasse (Saccharum L.). The analytical hierarchy process (AHP) was applied for selecting the most suitable bedding material. Validation was performed using data from previous studies carried out in central-western Brazil on the effects of different types of bedding material on broiler carcass quality. Considering the selected criteria, several bedding materials were tested and ranked, and the results showed that wood-shavings litter was the best option (weight = 0.28), followed by rice husks (weight = 0.24). All other tested alternatives presented lower scores and were, therefore, not considered for use. The AHP approach was found to be an efficient tool to select the most appropriate litter material under specific scenarios.

Ad Hoc Wireless Sensor Networks Applied to Animal Welfare Research

Considering the importance of drinking water and its effect on broiler performance, drinking water quality was studied using six different litter materials. The presence of coliform bacteria and Escherichia coli was investigated. The following litter materials were used in the trial: wood shavings, rice husks, chopped Napier grass (Pennisetum pupureum), 50% sugarcane bagasse (Saccharum L.) + 50% wood shavings, 50% sugarcane bagasse (Saccharum L.) + 50% rice husks, and plain sugarcane bagasse (Saccharum L.). A number of 1620 Ross ® one-dayold chicks were reared in 54 pens measuring 4.5 m 2 each, equipped with a bell drinker and a tube feeder. Water samples were collected in sterile tubes on days 28 and 42 of the rearing period, and submitted to the laboratory for analyses. Microbiological data were organized by classes expressed in a logarithm scale, where the lowest contamination corresponds to class 1 and the highest contamination to class 4. Results showed that total coliform contamination was higher on day 28 than in the end of the rearing period, and that E. coli presence was detected during both analyzed periods. The litter materials that presented lower degree of water contamination, predominantly class 1, were sugarcane bagasse and 50% of sugarcane bagasse and 50% of rice husks.

Multi-criteria analysis of the influence of rearing, equipment, and catching management practices on the Incidence of back scratches in broilers

Ad hoc Wireless Sensor Networks (AWSN) are arrays of miniaturized electronic devices that embed sensors and have communication capabilities that allow them to interconnect using a radio network. They are available with different technologies, configurations, and sensing capabilities, and can be used on different network topologies. As an AWSN is composed of a large number of compact low-cost and energy-constrained sensor nodes, it offers unprecedented flexibility and mobility, which makes them suitable for environmental data acquisition in the field, and allows fine-granular observations. The sensors are easy to deploy and can be used to detect previously unrecognized relationships and behaviors in natural systems, which cannot be detected by conventional approaches. In many cases, power consumption is still an issue. Research related to biological and environmental systems can be enhanced with AWSNs. Monitoring and control of the quality of indoor environment is very important for animal health and welfare and directly impacts productivity and quality. The goal of this work was to evaluate the capability and usefulness of an AWSN in studies related to animal housing environment. An AWSN has been set up and applied to monitor environmental variables in an animal housing facility. The network is composed of several sensing nodes and a gateway that links the network to a microcomputer. They were distributed over strategic points inside an animal housing facility to allow us to collect data about those environmental variables in real time. The inherent flexibility and mobility of the nodes allowed us to move them through the facility to determine different profiles of temperature, humidity and luminosity across the facility. Model based on this data can be derived to enhance animal welfare.

Desenvolvimento microbiológico em carne suína PSE e normal armazenada sob refrigeração

Carcass quality is one of the main parameters to evaluate broiler welfare, and the presence of back scratches indicates that the birds were submitted to stress. The objective of this study was to identify the best management practices during rearing and catching, taking into consideration broiler genetic differences (genetic lines A and B) and sexes. The survey was carried out in 351 broiler houses belonging to an integrated company and located in the region of Dourados, MS, Brazil. Between January and October, 2010, 2% of broilers of all ages (one to 43 days old) in all flocks were sampled. The sampled flock was evaluated in 21 d intervals. Scratches were classified as present or absent. The results indicated that catching management has the strongest influence on back scratches (73%), followed by rearing management (17%) and equipment management (10%). In general, strain A females presented the lowest probability of presenting scratches after weighing, equipment management, and catching. It was concluded that, although rearing and equipment management practices affected the presence of scratches, catching caused the highest percentage of lesions in birds of both strains, and therefore, it is considered critical. Broilers from distinct that genetic strains reacted differently to management practices due to their temperament and growth rate. Therefore, broilers should be housed according to genetic strain due to their different temperaments.