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The objectives of this study were: 1) to compare the effects of live yeast (LY), yeast fermentation product (YFP), a mix of Lactobacillus acidophilus and Propionibacterium freudenreichii (MLP), and Lactobacillus plantarum included as additives in dairy cows’ diets on in vitro ruminal fermentation and gas production (GP); and 2) to evaluate the effects of L. plantarum as direct-fed microbials (DFM) in dairy cows’ diets on in vitro ruminal fermentation, GP, nutrient digestibility, and N metabolism. Three experiments were carried out: Exp. 1 had the objective to compare all additives regarding ruminal fermentation parameters: an Ankom GP system was used in a completely randomized design, consisting of four 48 h incubations, and eight replications per treatment. There were eight treatments: a basal diet without additive (CTRL) or with one of the following additives: LY, YFP, MLP, or L. plantarum at four levels (% of diet Dry Matter (DM)): 0.05% (L1), 0.10% (L2), 0.15% (L3), and 0.20% (L4). In Exp. 2, a batch culture was used to evaluate ruminal fermentation, and CO2 and CH4 production using the same treatments and a similar experimental design, except for having 16 replications per treatment. Based on Exp. 1 and 2 results, Exp. 3 aimed at evaluating the effects of the L. plantarum on ruminal true nutrient digestibility and N utilization in order to evaluate the use of L. plantarum as DFM. The treatments CTRL, MLP, L1, and L2 were used in a replicated 4 × 4 Latin square design using a dual-flow continuous culture system. Data were analyzed using linear and nonlinear regression; treatment means were compared through contrasts, and L treatments in Exp. 1 and 2 were tested for linear, quadratic, and cubic effects. In Exp. 1, all treatments containing additives tended to reduce OM digestibility as well as reduced total volatile fatty acids (VFA) concentration and total GP. The YFP had greater OM digestibility than LY, and MLP treatment had greater total VFA concentration compared to L. plantarum treatments. In Exp. 2, additives reduced CO2 production, and there were no major differences in CH4. In Exp. 3, all additives reduced NH3-N concentration. In conclusion, pH and lactate concentration were not affected in all three experiments regardless of additive tested, suggesting that these additives may not improve ruminal fermentation by pH modulation; and L. plantarum may improve ruminal N metabolism when used as DFM in high-producing dairy cows’ diets, mainly by reducing NH3-N concentration.

The objective of this study was to evaluate the effects of Lactobacillus inoculants on fermentation, losses, and aerobic stability of a total mixed ration (TMR) silage. A TMR, formulated to meet the requirements of dairy cows producing 25 kg of milk/d, was applied with the following treatments prior to ensiling: 1) Control (CON), 2) Lactobacillus buchneri (10(5) cfu/g of fresh forage; LB), and 3) Lactobacillus plantarum (10(5) cfu/g of fresh forage; LP). TMR silages were ensiled for 15 and 60 d in silos equipped with an apparatus for determination of gravimetric DM, gas, and effluent losses. The experiment was performed in a complete randomized design with a 3 × 2 factorial arrangement of the treatments, with 5 replicates per treatment. Chemical changes, microbial counts, fermentation profile, and aerobic stability were measured after opening the silos. Data were submitted to ANOVA, and means were compared by Tukey and T-test and statistical significance was declared at P ≤ 0.05. After 15 d of ensiling, the inclusion of inoculant decreased NDF (P < 0.05) and butyric acid concentrations (P < 0.05) in TMR. LP had the lowest aerobic stability (P < 0.05) and the greatest loss of DM (P < 0.03). Ensiling for 60 d increased ammonia nitrogen (NH(3)-N), lactic acid bacteria (LAB), aerobic stability, and concentrations of lactic and acetic acid (P < 0.01) and lowered (P < 0.02) total fermentation losses compared to 15 d across all treatments. After 60 d of ensiling, LP lowered pH to the greatest extent. Treatment had no effect on concentrations of DM, CP, ADF, ash, and EE, as well as in vitro DM digestibility. In conclusion, inoculants containing LP or LB did not improve fermentation profile, did not prolong the aerobic stability, nor reduced losses. Furthermore, the 15-d ensiling period was insufficient for adequate bacterial activity.

The effect of nitrogen (N) fertilization on the dry-matter (DM) yield and nutritional value of sorghum (Sorghum sp., cv. Jumbo) and black oat (Avena strigosa cv., IPR 61) was investigated in the context of forage and livestock production in southern Brazil. Sorghum was cultivated with 0, 37·5, 75, 150, 225, 300 and 375 kg N ha−1 during the summer crop seasons of 2010/11 and 2011/12. Black oat received 0, 40, 80, 120, 160, 200 and 240 kg N ha−1 in the winter of 2011. According to the adjusted polynomial regression, sorghum DM yield increased in response to N up to 288 (12·9 t ha−1) and 264 kg ha−1 (5·6 t ha−1) in 2010/11 and 2011/12 respectively. Crude protein (CP) content of sorghum was highest at 349 and 328 kg N ha−1, but in vitro dry-matter digestibility (IVDMD) was highest at 212–207 kg N ha−1 in 2010/11 and 2011/12 respectively. Sorghum neutral detergent fibre (NDF) and acid detergent fibre (ADF) were not affected by N fertilization. In black oat, the maximum DM yield (6·0 t ha−1) was obtained with 187 kg N ha−1; the IVDMD, NDF and ADF were not affected by N fertilization, but the CP content increased up to 220 kg N ha−1. It is concluded that these forage species can improve the year-to-year amount and quality of forage produced but high rates of N fertilizer are required to achieve high yields. Fertilizer N rates of 210–280 kg N ha−1 in sorghum and 180 kg N ha−1 in black oat in the crop rotation provide the greatest responses in DM yield consistent with good nutritional quality for livestock production.

SUMMARY Vision is important in poultry behavior and welfare. Poultry have highly specialized visual systems, and the majority of their behavior is mediated by vision. In the present study, we evaluated the lighting preference of broiler chickens exposed to different lighting sources and their production performance. In the first portion of the study, we evaluated the preference of birds for white and yellow lighting provided by light-emitting diode (LED) bulbs. Bird preference was assessed by videos recorded during the experiment. In the second portion of the study, we evaluated the performance of broiler chickens exposed to LED and compact fluorescent lamps (CFL). Performance was assessed in terms of mortality rate, bird BW, daily BW gain, feed consumption, and feed conversion. The chickens occupied environments with yellow and white LED lighting evenly and did not show any behavioral sign of preference for one of the environments. However, birds presented greater feed consumption at 21, 28, and 35 d of age when exposed to white LED lighting. Generally, birds exposed to LED lighting presented better production performance than birds under the CFL. Seven-day-old male chickens presented better feed conversion under LED illumination than did males of the same age under CFL.

Phosphorus (P) is one of the most limiting mineral elements for biomass and grain production in tropical soils. This study was undertaken to assess the influence of P on herbage accumulation (DM) and the nutritive value of forage sorghum (Sorghum bicolor) and black oat (Avena strigosa) in succession. Evaluated treatments were P fertilization levels of 0, 50, 100, 150 and 200 kg of P2O5 ha-1 distributed in a randomized complete block design with three replicates. The treatments were applied at sorghum seeding in the summer 2010/2011 and 2011/2012. Black oat was seeded following sorghum in 2011 with no additional P fertilization. Herbage production and its nutritive value were assessed by successive cuts. The greatest sorghum DM yields were obtained at the highest phosphate level tested (200 kg P2O5 ha-1), with residual response in subsequent black oat. There was no effect of P fertilization levels on the nutritive values of both crops, considering crude protein (CP) levels, in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF) and acid detergent fiber (ADF), what demonstrates that P addition has no effect in forage nutritive value, especially when the soil P levels are classified as medium or high. The plant P recovery efficiency decreased when increasing P fertilization levels for both sorghum and black oat. The level of 50 kg P2O5 ha-1 year-1 presented the greatest P recovery by plants, which supports the idea of less fertilizer use with more efficiency.

This experiment was carried out in a 104 m² poultry house located between the geographical coordinates 25°45'00" south latitude and 53°03'25" west longitude and an average altitude of 550 m, from September to November, 2008. The chickens were placed in 12 pens measuring 2 m² each at a stocking density of 12 chickens m-2. This study aimed at evaluating the effect of two different initial weights (chick weight on first day of experiment) and two types of litter material on broiler production parameters, litter humidity, as well as on breast and footpad lesions. A total of 240 female Cobb® chickens, derived from the same flock of breeders, was distributed in a completely randomized experimental design with a 2 (initial weight) by 2 (litter material) factorial arrangement with three replicates per treatment. Initial weights were classified as light (34.40 - 35.22 g) or heavy (39.29 - 41.30 g), whereas wood shavings and sawdust were used as litter material. Data were analyzed by ANOVA and means were compared by Tukey's test at 95% confidence level. Initial weight significantly influenced bird performance, as chickens with heavy initial weight presented higher feed intake and body weight. Type of litter did not have any effect on breast injuries and litter humidity. However, the wood shavings litter significantly influenced footpad lesions.

Balance between nutrient uptake by the crop and the amount of applied fertilizer is desired in a production system, and this measurement can predict the nutrient use efficiency. The present study aimed to evaluate nitrogen- (N-) use and recovery efficiency and extraction of N, phosphorus (P), and potassium (K) by sorghum (Sorghum bicolor) and black oat (Avena strigosa) forages under nitrogen fertilization in three consecutive crop cultivation. The experiment was carried out at Federal Technological University of Paraná (UTFPR), Dois Vizinhos, Paraná, Brazil, in Rhodic Hapludox soil. Treatments included 0, 37.5, 75, 150, 225, 300, and 375 kg N ha−1applied to sorghum in the summer seasons of 2010/2011 and 2011/2012, intercalated by, respectively, 0, 40, 80, 120, 160, 200, and 240 kg N ha−1applied to black oat in the winter/2011. Forage production, N, P, and K extraction, and N recovery efficiency were determined through samplings during the crop cycle. The highest sorghum forage production and N and K extraction were under 230 to 300 kg N ha−1, which was around 190 kg N ha−1for black oat. The values of N recovery, efficiency, and N-use physiological efficiency were higher under lower N rates for both crops. Based on this, about 150 kg N ha−1is recommended to obtain good sorghum forage production with higher N efficiency levels, which is about 120 kg N ha−1for black oat.

The present study evaluated the preference and the production performance of broiler chickens exposed to different lighting sources. The first portion of this study evaluated bird preference to white and yellow lighting provided by Light-Emitting Diodes (LED). Bird preference was assessed through images recorded during the experiment. The second portion of this study evaluated the performance of broiler chickens under the exposure of Light –Emitting Diodes and Compact Fluorescent bulbs. Performance was assessed in terms of mortality rate, bird weight, weight gain, feed consumption and feed conversion.