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) among treatments, with the best results obtained with red LED, white LED, and incandescent light sources. Egg weight, feed intake, and internal egg quality (albumen height, specific gravity, and Haugh units) were not influenced (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.

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Infection with Eimeria sp. results in the activation of multiple facets of the host immune system; the use of phytogenics can modulate the inflammatory response and improve the performance of the challenged animal. The aim of this study was to evaluate the effect of a commercial blend of cashew nut shell liquid (CNSL) and castor oil on the immune response of broilers challenged with coccidiosis. A total of 864 one-day-old male chicks (Cobb 500) were randomly distributed into six treatment groups (8 pens/treatment and 18 chicks/pen) in a three-by-two factorial design with three additives: control (non-additive), 100 ppm of monensin or 0.15% CNSL–castor oil. Challenge status was determined twice at 14 days of age. Unchallenged birds were inoculated by gavage with oocysts sporulated with Eimeria tenella, Eimeria acervulina and Eimeria maxima. Although the positive control (non-additive and challenged) and CNSL–castor oil treatment groups exhibited similar variation in weight gain (ΔBWG) compared to unchallenged birds fed without additives, the variation observed in birds fed diets containing CNSL–castor oil was associated with a higher maintenance requirement and not feed efficiency. In the second week after infection, ΔBWG of the CNSL–castor oil treatment group did not significantly change compared to the other treatment groups. At days 7 and 14 post-challenge, there was a higher excretion of oocysts in the control group, whereas the CNSL–castor oil and monensin groups did not differ. The CNSL–castor oil group exhibited increased gene expression of interferon (IFN), interleukin 6 (IL-6) and tumor necrosis factor (TNF), while the control group exhibited increased expression of cyclooxygenase (COX) and IL-1. The heterophils/lymphocyte ratio was low for the monensin treatment group. The unchallenged birds that received monensin treatment presented higher gene expression of IFN, COX and IL-1 compared to the other treatments, while the CNSL–castor oil group exhibited reduced gene expression, except for TNF. The commercial blend of cashew nut liquid and castor oil modulated the inflammatory response against Eimeria spp. In the absence of the parasite, there was no stimulation of genes involved in the inflammatory response, demonstrating that the blend is an effective tool in specifically modulating the immune system of birds afflicted with coccidiosis.

This study aimed to identify the influence of climate pattern and rearing conditions on broiler carcass condemnations observed during processing. We evaluated the registered data of 2015 from the federal inspection files in all broiler slaughterhouses located in the state of Mato Grosso do Sul, Midwestern Brazil. The percentages of condemnations by airsacculitis, cellulitis, dermatosis, ascites syndrome, total carcass condemnations, and average broiler weight at 42 days were analyzed. Data were associated with housing systems and season of the year in which each flock was reared. Two-way ANOVA was applied to the data in a completely randomized design 4×3 (four seasons and three houses) and compared by Tukey's test. The results indicated that the housing system did not affect the studied condemnations, and seasons of the year did not change condemnation by airsacculitis; however, the other pathologies leading to carcass condemnations were affected by season. Condemnations by cellulite were higher during summer than in winter. For dermatosis, the maximum index appears during summer and the lowest during winter and spring. The ascites syndrome presented the smallest index in summer and winter, and the minimum value was found in spring. The average bird weight was higher in autumn than in winter and spring. Type of broiler rearing did not affect the carcass condemnation index. Summer was the most detrimental period regarding the condemnation rates for the pathologies studied, mainly cellulitis and dermatosis, while the highest average weight of birds was found during autumn and spring.

Vitamin D is added to broiler diets to supply its physiological requirement for bone formation. The fast growth rate of modern broilers is often associated with poor bone formation. Increasing vitamin D supplementation levels and the use of more available sources have applied to try to prevent leg problems, to increase carcass yield, and to improve the performance of broilers. The present study evaluated three vitamin D supplementation levels (1) 3,500 IU (control); (2) control + 1,954 IU of 25-hydroxycholecalciferol; and (3) control + 3,500 IU of vitamin D in broiler diets supplied up to 21 days of age. The objective was to investigate if the vitamin D levels above the recommendations could reduce leg problems in broilers. In this experiment, a total of 1,296 oneday-old male and female Cobb® 500 broilers were used. A 2 x 3 factorial arrangement was applied, consisting of two sexes and three vitamin D levels. No difference was found between the levels of vitamin D (p > 0.05), the performance of males or females, the gait score, the valgus and varus incidence, the tibial dyschondroplasia incidence, the occurance of femoral degeneration, the bone colorimetric, and the carcass yield. Parts yield differences were found (p > 0.05), except for liver and intestine yields. We concluded that the lowest tested vitamin D level (3,500 IU per kilogram of feed) added to the diet was the best choice in terms of cost/ benefit to help minimizing leg problems in broilers.

Light is an important environmental factor for birds, allowing not only their vision, but also influencing their physiological responses, such as behavioral and reproductive activity. The objective of this experiment was to evaluate the impact of different colors of monochromatic light (LED) sources in laying hens production during the second laying cycle. The study was conducted in an experimental laying house during 70 days. A total of 300 laying hens Isa Brown® genetic strain, aged 95 weeks, in the second laying cycle were used in the study. The artificial light sources used were blue, yellow, green, red and white. The light regimen was continuous illumination of 17 h per day (12 h natural and 5 h artificial) in a daily light regimen of 17L:5D (light: dark). The Latin Square design was adopted with five treatments (five colors) divided into five periods, and five boxes, with six replicates of ten birds in each box. The production and egg quality were evaluated. The different colors of light source did not affect production parameters or egg quality (p > 0.05). The monochromatic light source may be considered as an alternative to artificial lighting in laying hens during the second production cycle.

The pre-slaughter period is considered critical in broiler production. Several factors contribute to increase the birds' stress, such as handling, harvesting, and transportation, negatively affecting their welfare. This study aimed at evaluating the addition of lemon grass (Cymbopogon citratus Stapf) to the drinking water of broilers during the pre-slaughter period on their behavior, blood cortisol, and surface temperature. The study was carried out at the experimental farm of the Federal University of Grande Dourados (UFGD), Dourados, MS, Brazil. In total, 2594 broilers were distributed according to a completely randomized experimental design, in a 3x2x2 factorial arrangement, with four replicates per treatment. Treatments consisted of three different lemon grass levels (Cymbopogon citratus Stapf) used in the form of an infusion (0, 0.1, and 5 g per L of water), sex (male or female), and genetic strain (Ross® 308 or Cobb® 500). The infusion was offered when birds were 42 days old. On that day, blood was collected for blood cortisol level determination, broiler surface temperature was recorded, and an ethogram was applied to register broiler behavior. Blood cortisol level and broiler surface temperature were not affected by treatments (p>0.05). The behavior of beak opening was different between the genetic strains (p<0.05), being more frequent in Ross® 308 broilers. Lemon grass water content did not affect broilers' surface temperature when consumed during the pre-slaughter period.