Effects of guavira fruit (Campomanesia adamantium) peel extract on performance and meat quality of broilers

This article assessed the performance, carcass yield, and meat quality of finishing broilers fed increasing levels of hydroethanolic extract of guavira fruit peel (HEGP) were assessed. A total of 480, three-weeks-old male broilers were randomly allocated to dietary levels of HEGP (0, 100, 200, 300, 400, and 500 mg/kg), with five replicates and 16 birds each. There was a quadratic effect of HEGP inclusion on weight gain (WG) and feed conversion ratio (FCR), with the greatest WG and FCR being calculated at levels of 314 and 219 mg/kg HEGP, respectively. Broilers fed diets containing the extract had better performance than those fed an extract-free diet. There was no effect of extract inclusion on carcass yield and cuts. There was a quadratic effect of HEGP inclusion on a* (redness) of thigh meat at 15 min post-mortem, and on water-holding capacity (WHC), with the lowest and highest values being calculated at 270 mg/kg and 263 mg/kg HEGP, respectively. There was a quadratic influence of HEGP inclusion on the malonaldehyde content at 30-day storage, with highest value being calculated at 218 mg/kg HEGP. Dietary inclusion of 219 mg/kg of HEGP resulted in better FCR for broilers in the finishing phase but without improvement in meat quality

Impact of dried brewers’ grains supplementation on performance, metabolism and meat quality of broiler chickens

The objective was to evaluate increasing levels of dried brewers’ grains (DBG) in feed for broiler chickens from 1 to 21 days old and their effect on performance, blood parameters, intestinal morphometry, carcass characteristics and meat quality. The design was completely randomized with six treatments, which consisted of various levels of DBG inclusion, namely 0 (no inclusion), 20, 40, 60, 80, and 100 g/kg with seven replications and 17 animals per experimental unit, totalling 714 male broilers. Performance parameters, blood biochemical profile, morphology of the intestinal epithelium (duodenum), and carcass yield and composition were evaluated. Feed intake was not changed by DBG inclusion levels. Nor were weight gain and feed conversion ratio. Serum cholesterol levels were not influenced, and there were no effects on triglyceride, uric acid and creatinine levels. Enzyme aspartate aminotransferase showed a quadratic effect, as did alanine aminotransferase, with higher values at 79.5 and 63.9 g/kg DBG inclusion, respectively. No changes in carcass yield and relative organ weight were observed. The composition of the carcass in ether extract showed a quadratic effect, as fat deposition rate, with lowest values at 62.8 and 62.4 g/kg of DBG inclusion levels, respectively. Crude protein levels in carcass reduced linearly, as did fat deposition rate. The parameters of intestinal morphology and meat quality were not changed. Dried brewers’ grains can be included in broiler diet from 1 to 21 days at levels up to 100 g/kg without influencing the metabolic parameters and broiler performance. Keywords: alternative feed, blood, by-product, intestinal villi, performanc

Influence of phytate and phytase on performance, bone, and blood parameters of broilers at 42 days old

The objective was to evaluate the effect of diets containing various levels of phytate and phytase on broilers from 1 to 42 days old. The treatments consisted of a combination of diets containing high (HP), medium (MP) and low (LP) phytate with positive control diet (PC) and a negative control diet (NC) that was similar to the PC in energy and protein but with less calcium and phosphorus. Three additional diets, based on the NC were supplemented with 500, 1000, or 1500 FTU kg-1 of phytase. Broilers that received the NC diet exhibited the lowest weight gain (WG), whereas those supplemented with 1000 FTU kg-1 obtained 2.84% higher WG compared with PC. Broilers that received NC had the lowest breaking strength and dry matter. Birds fed HP diets that received NC and NC + 500 FTU kg-1 had a higher concentration of serum Ca and P than birds fed LP diets. Broilers fed the NC and NC + 500 and 1000 FTU kg−1 had lower tibia Ca levels compared with birds fed the PC. Broilers fed HP diets had higher tibia Ca content than MP. Phytase supplementation had a positive response in diets with reduced Ca and P. Based on regression analysis the optimum inclusion of phytase to improve broiler performance parameters was calculated as 952 FTU kg-1

Effects of feed particle size on energy values for broiler chickens at various ages

The objective of this study was to evaluate the effects of various geometric mean diameters (GMDs) of particles of corn, pelleted soybean meal and a corn-soy mixture in the proportion of 70% and 30%, respectively, on the nutritional value of the feeds. The study evaluated energy consumption, the contents of apparent metabolizable energy (AME) and AME corrected for nitrogen balance (AMEn) and the metabolizability coefficients for broiler chickens at various ages. A total of 540 Cobb 500 male broilers were housed in metabolic cages (experimental units). Trials were performed separately with each feed. A completely randomized design was used with four treatments, namely corn with 573, 636, 851, and 1012 μm GMDs; pelleted soybean meal with 538, 550, 665, and 741 μm GMDs; and the corn-soy mixture with 627, 658, 893, and 1040 μm GMDs. Birds were evaluated on days 1 - 10, 11 - 20, 21 - 30, and 31 - 40. Larger GMDs resulted in lower energy consumption. From 1 to 10 days, birds consumed less metabolizable energy than older birds. Birds fed corn from days 1 to 10 had higher metabolizable energy (P <0.05) with increasing GMD up to 1042 μm. However, the results varied, depending on the feed and its combinations. The use of coarse particles could reduce the costs of grinding, and would have few effects on the metabolizable energy of broiler chickens

Bone Characteristics Of Broiler Chickens Fed Diets Supplemented With Solanum Glaucophyllum

The aim of this study was to assess the characteristics of the tibiotarsus of male broilers at 21 and 35 days of age. The percentages of collagenous proteins (CP), non-collagenous proteins (NCP), ash, and minerals (calcium, phosphorus, potassium and sodium), as well as weight of dried and defatted tibiotarsus in natura were determined. A total of 648 Cobb® male broilers were used in a random block design study with 6 treatments, 6 replicates, and 18 birds per experimental unit. The treatments consisted of diet supplementation with 0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 μg of active Vitamin D3 per kg of feed. The birds were weighed at 21 and 35 days of age and one bird per repetition with the mean weight of the experimental unit was slaughtered to collect the tibiotarsus. The organic and mineral composition of the bone was affected by the addition of active Vitamin D3 to the feed. Our results indicate that a dose of up to 1.50 μg of 1,25(OH)2D3/kg of feed is ideal for male broilers between 8 and 35 days of age.37138139

Response of vegetation to fire disturbance: short-term dynamics in two savanna physiognomies

Fire is a constitutive ecological force in savanna ecosystems, but few studies have monitored its short-term effects on plant community dynamics. This study investigated changes in plant diversity in the South American savanna (Cerrado) after severe disturbance by fire. We monitored 30 permanent plots (10 m × 5 m) distributed in two Cerrado physiognomies (típico: more forested; ralo: grass-dominated), being 10 plots in the area disturbed by fire, and five in a preserved control area (undisturbed). From August 2010 to June 2011, we evaluated changes in species richness, abundance and composition of savanna vegetation. Monitoring started one week after the fire; disturbed plots were surveyed monthly, while control plots were surveyed every two months. We observed rapid reassembling in both physiognomies: plots affected by fire showed rapid increase in species richness and plant density during the first four months after the disturbance. Concerning species composition, disturbed plots in the cerrado típico tended to converge to control plots after one year, but each local assemblage followed particular temporal trajectories. A different pattern characterized cerrado ralo plots, which showed heterogeneous trajectories and lack of convergence between disturbed and control plots; the structure of these assemblages will likely change in next years. In conclusion, our results showed that fire significantly affected plant diversity in the two savanna physiognomies (cerrado típico and ralo), but also indicated that community reassembling is fast, with different dynamics between Cerrado physiognomies