Abstract The aim was to evaluate the effect of different feeding volumes on the cut yield and meat quality of brown eggshell laying hens strain Embrapa 051 (E051) during the laying cycle, reared in an alternative system and slaughtered at 73 weeks, with reference to the lineage Lohmann Brown (LB). 600 hens E051 and 200 hens LB were used in an entirely randomized experimental design totalizing 5 replicates with 40 birds each. The treatments were: Control (LB fed with 100% of their dietary requirements), E051 fed with 93% of the control diet, E051 fed with 100% of the control diet, and E051 fed with 107% of the control diet. Birds were supplemented daily with 30g of ground grasses. Different feeding volumes did not alter the physicochemical quality of the meat and the cut yield. Body and cold carcass weight were greater in the E051 fed with 107% of the reference feed compared to the LB or the E051 fed with 7% less than the control diet. Yellow color intensity was greater in the E051 than in LB. The results demonstrated that, at the end of their productive cycle, the E051 without a restricted diet presents good carcass characteristics and potential for industrialized development. 05 E (E051 cycle 7 weeks . (LB) 60 E05 20 4 each 100 requirements, requirements , requirements) 93 107 g grasses that development 0 (E05 6 E0 2 10 9 (E0 1 (E

Abstract Male broiler chickens (384), Cobb 500, were housed in metabolic cages to assess the efficacy of phytase in diets with low and high phytate-phosphorus on the performance, bone physical characteristics, tissue and serum mineral deposits. Birds were distributed in four treatments with a 2 x 2 factorial arrangement in a completely randomized block design. Experimental diets based on maize-soybean meal were T1 – diet low phytate-phosphorus; T2 – diet low phytate-phosphorus and phytase (500 FTU/kg); T3 – diet high phytate-phosphorus; T4 – diet high phytate-phosphorus and phytase (500 FTU/kg). Feed intake, body weight, weight gain and feed conversion ratio were assessed. Two left tibias per experimental unit were analyzed for physical characteristics and mineral concentration; a section of skinless breast muscle and blood were collected to measure the concentration of calcium, phosphorus and sodium. Results showed interaction between bone stiffness and serum calcium. The inclusion of phytase in diets with low and high phytate-phosphorus did not alter performance, bone resistance and flexibility, mineral deposits in the tibia and breast muscle, but increased bone stiffness after 22 days of age. It also provided a higher serum calcium rate in broilers fed diets with low phytate-phosphorus up to 32 days of age. 384, 384 , (384) 500 phytatephosphorus phytate performance design maizesoybean maize soybean T (50 FTU/kg FTUkg FTU kg FTU/kg) FTU/kg. . intake assessed sodium flexibility age 3 38 (384 50 (5 (38 5 ( (3

Foram realizados três experimentos para avaliar o desempenho e o rendimento de cortes e carcaça de frangos de corte, recebendo ou não monensina (MON) na dieta, em diferentes doses (D) (100, 110 e 120 ppm), de acordo com as fases de crescimento (FC) (1 a 21, 22 a 40 e 41 a 45/46 dias de idade). O experimento 1 foi realizado em gaiolas metabólicas, no qual foram determinadas energia metabolizável aparente (EMA), digestibilidade da matéria seca - MS (DMS) e retenção de nitrogênio (RN). Os experimentos 2 e 3 foram realizados em boxes. No experimento 3, a conversão alimentar (CA) foi melhor nos tratamentos com MON, principalmente na FC de 22 a 40 dias. As doses de 100 e 110 ppm de MON mostraram melhor resposta que 120 ppm, sobretudo quando não houve retirada na droga nos cinco últimos dias da FC. No experimento 3, as aves que não receberam MON tiveram maior consumo de ração (CR). Não foram observadas diferenças na DMS, EMA e RN das rações experimentais. Nos experimentos 1 e 2, a manutenção da droga na última semana influenciou positivamente o rendimento de carcaça e a dose de 110 ppm mostrou maior rendimento de peito que as demais. A gordura abdominal não foi influenciada pelas doses de MON nas dietas. O uso de MON influenciou positivamente a CA de frangos de corte. Apesar do reduzido CR, o ganho de peso das aves que receberam MON na dieta não foi alterado.

Three experiments were conducted to evaluate the performance and carcass yield of broilers, receiving or not monensin (MON), at different levels (100,110 and 120 ppm) according to the growth phase (GP) (1 to 21; 22 at 40 and 41 to 45/46 days of age). The Experiment 1 was performed at metabolic cages and the AME, dry matter digestibility (DDM.) and nitrogen retention (NR) were determined. The Experiments 2 and 3 were performed at floor pens. In the Experiment 3, feed:gain ratio (F/G) was improved with MON, mainly from 22 to 40 days. The 100 and 110-ppm levels better responded than 120 ppm, mainly without drug withdrawal in the last GP. In the Experiment 3, birds without MON had higher feed intake (FI). No differences were observed in DMD, ME or NR. In the Experiments 1 and 2, the maintenance of the drug up to the last week positively influenced the carcass yield and 110-ppm dose showed higher breast yield than other levels. Abdominal fat was not affected by the MON levels in the diets. The use of MON positively affected the broiler F/G. The birds weight gain was not affected, even with reduced CR.