An experiment was carried out to verify the response to the Ca reduction levels of diets with different vitamin D sources on performance, bone mineral deposition, serum concentrations, digestibility, carcass characteristics, and meat quality of broiler chickens in the period from 1 to 42 days reared in thermoneutral environment. A total of 504 male broilers with one day of age and average weight of 43.27±1.08 g were housed in climatic chambers and distributed in a completely randomized design. The study consisted of a 4×2 factorial, with four Ca reduction levels (0, 10, 20, and 30%) and two vitamin D sources (2760 IU of D 3 or 25-OH-D 3). The performance of animals at 21 and 42 days of age was not affected by Ca reduction by up to 30%, regardless of the vitamin source used. Dietary reduction from 10% decreased serum Ca concentrations. The use of vitamin D 3 provided a serum P level greater than the 25-OH-D 3. Calcium reduction decreased serum 25-OH-D 3 levels. No effect of vitamin source or Ca levels on broiler carcass characteristics was observed at 42 days. The vitamin source did not influence meat quality, while Ca reduction of the diet provided lower losses by thawing and cooking and higher initial pH values. The b* color was reduced in diets with lower Ca levels of the diet. Reducing Ca up to 30% does not affect the performance and carcass characteristics, regardless of the vitamin D source used. The quality of broiler meat is improved with the Ca reduction in the diet, but the vitamin used has no effect on such characteristics. We can conclude, based on the results of performance, blood, and bone, that the performance variables are not adequate to determine the actual requirement of Ca, since as it is a priority to maintain performance, bone mineral mobilization occurs, which may compromise the carcass quality of the birds.

ResumoO trabalho foi realizado com o objetivo de avaliar os parâmetros de qualidade do leite segundo três níveis de especialização das unidades de produção de leite de diferentes municípios do Oeste Catarinense. A caracterização das unidades de produção de leite foi realizada utilizando-se um questionário em 29 propriedades rurais como instrumento de coleta de dados, aplicado durante a visita à propriedade rural. Também foram coletadas 58 amostras de leite dos tanques de resfriamento para a determinação dos níveis de gordura, proteína, lactose, contagem de células somáticas (CCS) e contagem bacteriana total (CBT). Considerando-se as informações obtidas, as unidades de produção de leite foram classificadas em: especializado (E), semiespecializado (SE) e não especializado (NE). Os dados foram submetidos a métodos multivariados de análise estatística, com o emprego da Análise de Componentes Principais (ACP) e da Análise de Redundância (RDA). Os resultados das análises indicam que o tempo na atividade, a área com pastagem perene, a renda bruta com bovinos de leite, o tipo de ordenha, a lavagem dos tetos e o método de reprodução são as variáveis que mais interferem na qualidade do leite. O aumento do nível de especialização da atividade leiteira, mesmo produzindo menor porcentagem de gordura e proteína no leite, proporciona a obtenção de leite de melhor qualidade, devido aos menores índices de CCS e CBT, associadas principalmente, à maior renda proporcionada pela atividade. Nas propriedades especializadas, a atividade leiteira apresenta maior importância econômica, estimulando o produtor a adotar melhores práticas de higiene na ordenha e de reprodução do rebanho. Palavras-chave: Composição do leite, ordenha, práticas de higiene, renda do leite AbstractThis work was aimed to evaluate milk quality parameters according to three levels of specialization of milk production units in different districts of West Santa Catarina´s State, Brazil. Characterization of milk production units was carried out using a questionnaire in 29 farms as a tool for data collection, applied during a visit to the farm. At the time, 58 milk samples were collected from cooling tanks to determine the levels of fat, protein, lactose, somatic cell count (SCC) and total bacteria count (TBC). Considering the information obtained the milk production units were classified as specialized (E), semi-specialized (SE) and not specialized (NE). The database was subjected to multivariate methods of statistical analysis with the use of Principal Component Analysis (PCA) and Redundancy analysis (RDA). The results indicated that variables that most influence milk quality are: time in the activity, area with perennial pasture, gross income from milk activity, type of milking, teat washing and method

Two trials were conducted to determine the non-phytate phosphorus (nPP) requirement for broiler under heat stress. In both trials, birds were distributed in a completely randomized 4 × 2 factorial design with four nPP concentrations: 0.25, 0.35, 0.45, and 0.55%, and two Ca supply techniques: Ca fixed at 0.899% (CaF) or varying along with nPP aiming a 2:1 Ca to nPP ratio (CaV). Both trials had eight pens/treatment, with nine and five birds/pen for exp. 1 and exp. 2, respectively. nPP concentration had no effect on feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), nor fat deposition ratio (FDR). nPP levels showed a linear effect on protein deposition ratio (PDR) only for CaF diets. The nPP levels had a significant effect, regardless the technique adopted, on tibia phosphorus (TibP), which varied quadratically, on tibia calcium (TibCa) that increased quadratically and linearly, respectively, on CaF and CaV diets, and on tibia ash (TibAsh) that showed a quadratic effect for both. No effect was observed on Ca to P ratio in the tibia (TibCa:TibP). The nPP levels showed a linear increase effect over phosphorus intake (PI), phosphorus excreted (PE), and phosphorus retained (PR), and a linear decrease effect on phosphorus retention coefficient (PRC). Therefore, the nPP requirement for broilers from 8 to 21 days of age that provided better performance and bone variables were 0.250 and 0.484%, respectively, for CaF diets and 0.250 and 0.511%, respectively, for CaV diets.

-This study was conducted to evaluate the effect of reduction of the available phosphorus (avP) in diets supplemented with 500 FTU/kg phytase on performance, carcass characteristics, and bone mineralization of broilers aged 22 to 42 days kept in a high-temperature environment. A total of 336 Cobb broilers with an average initial weight of 0.883±0.005 kg were distributed in a completely randomized design with six treatments -a positive control (0.354 and 0.309% avP without addition of bacterial phytase for the phases of 22 to 33 and 34 to 42 days, respectively), and another five diets with inclusion of phytase (500 FTU) and reduction of the level of avP (0.354, 0.294, 0.233, 0.173, and 0.112%; and 0.309, 0.258, 0.207, 0.156, and 0.106% for the phases of 22 to 33 and 34 to 42 days, respectively) -eight replicates, and seven birds per cage. The experimental diets were formulated to meet all nutritional requirements, except for avP and calcium. Birds were kept in climatic chambers at a temperature of 32.2±0.4 °C and air humidity of 65.3±5.9%. Phytase acted by making the phytate P available in diets with reduction in the levels of avP, keeping feed intake, weight gain, feed:gain, and carcass characteristics unchanged. Treatments affected ash and calcium deposition and the Ca:P ratio in the bone; the group fed the diets with 0.112 and 0.106%, from 22 to 33 and 34 to 42 days of age, respectively, obtained the lowest values, although the phosphorus deposition in the bone was not affected. Diets supplemented with 500 FTU of phytase, with available phosphorus reduced to 0.173 and 0.156%, and a fixed Ca:avP ratio of 2.1:1, meet the requirements of broilers aged 22 to 33 and 34 to 42 days, respectively, reared in a high-temperature environment.

Keywords Branched-chain amino acids, Coturnix coturnix coturnix, ideal protein.Submitted: 27/October/2016 Approved: 08/January/2017 ABSTRACT This study was conducted to determine the optimum standardized ileal digestible isoleucine to lysine (SID Ile:Lys) ratio for meat-type quails from 15 to 35 d of age. Three hundred fifty not-sexed meattype quails (Coturnix coturnix coturnix) were randomly assigned into five treatments, with seven replicates of 10 quails each. An isoleucinedeficient corn-soybean meal-based diet was formulated and graded supplemented with L-isoleucine (99%) to obtain diets containing SID Ile:Lys ratios of 55,61, 67, 73, and 79%. Data were analyzed as oneway ANOVA and optimum SID Ile:Lys was estimated by polynomial (linear and quadratic) regression. Statistical differences were considered when p<0.05. Quail performance from 15 and 21 d and 15 and 28 d of age was not affected by the treatments. From 15 to 35 d of age, body weight gain and body weight exhibited a quadratic response to increasing dietary SID Ile:Lys ratios, and were optimized at 66 and 67% SID Ile:Lys, respectively. Feed conversion ratio was not influenced by SID Ile:Lys ratios in any of the phases assessed herein. Based on the results, the optimum SID Ile:Lys ratio for meat-type quails from 15 to 35 d of age is 67%.