Efficiency of lysine utilization by growing meat quail.

The objective of present study was to estimate the efficiency of lysine utilization by meat quail of 21 to 35 d of age. A total of 500 meat quails were distributed in a completely randomized design in a 2 × 5 factorial arrangement, with 2 sexes (male and female) and 5 digestible lysine levels (0.714, 0.816, 0.918, 1.020, and 1.122%) and 5 replications of 10 birds each. The variables studied were feather-free body weight (FFBW), feed intake (FI), lysine intake (LysI), feather-free body protein deposition (FFBPD), feather-free body lysine deposition (FFBLysD), feather-free body fat deposition (FFBFatD), feather weight (FW), feather protein deposition, feather lysine deposition, and feather fat deposition. The FFBW, FFBPD, FFBLysD, and FFBFatD were regressed as a function of LysI for each sex to estimate the efficiency of lysine utilization in the feather-free body (ELysFFB), and the individual equations were compared. In addition, a multiple regression without intercept was also used to estimate the ELysFFB and in feathers (ELysF) individually. To compare the ELysFFB obtained by the different methods, the t-statistic was used. There was no effect on sex × lysine level interactions for any variable. The females showed higher FFBW (5.07%) and FFBFatD (26.23%) than males. All variables increased with the level of dietary lysine, with the exception of FI, FW, and the deposition of nutrients within them. The ELysFFB values obtained by simple linear regression and multiple linear regression were 48.0 and 44.6%, respectively. As there was no difference in the efficiencies estimated by the different methodologies, the best estimate of ELysFFB was 46.3%, that is, the average. The best estimate of ELysF was 18.1%, obtained by multiple linear regression.

Allometric coefficients of major chemical components of meat quail raised in different thermal environments.

The objective of the present study was to estimate and compare allometric coefficients of the major chemical components of meat quail raised in different thermal environments, based on protein weight of feather free body (FFB) and feathers. In total, 300 meat quail, males and females, were distributed in a completely randomized design with 2 treatments (climatized environment, 26°C, and non-climatized environment, 29°C) and 6 replicates of 25 birds each. On the first day, 36 birds were selected to form the reference group and from this day on, 2 quail were weekly sampled from each cage. All selected birds were fasted for 24 h, weighed, slaughtered, plucked, and reweighed. The FFB and feathers were ground separately to obtain homogeneous samples, which were freeze-dried to determine the water content, and thereafter, ground again in a micromill before analyzing for protein, lipid, and ash using AOAC procedures. The adjustment of the allometric equations was made using crude protein (CP) weight as the independent variable and water, lipid, and ash weight as the dependent variables. The data of each dependent variable were transformed into natural logarithm (ln), regressed according to lnCP, and subjected to a parallelism test. In the FFB, water showed early development and lipid and ash showed late development in relation to the CP weight. In feathers, water and ash weight showed early development in relation to the feathers protein weight, whereas lipids showed late development. The environments of 26°C and 29°C did not affect the allometric coefficients that described the growth between the chemical components in the body and in the feathers, except for lipids in male FFB, that showed higher allometric coefficient at 29°C than 26°C. Describing the allometric relationships between the major chemical components of meat quail body is an important step in supporting future research comprised modeling of body growth and nutrition for meat quail.

Coeficientes alométricos das partes e dos órgãos de codornas de corte mantidas em diferentes ambientes térmicos / Allometric coefficients of the cuts and organs of meat quail kept in different thermal environments

Objetivou-se comparar os coeficientes alométricos (b) que descrevem o crescimento das partes e dos órgãos de codornas de corte mantidas em diferentes ambientes térmicos. Foram utilizadas 300 codornas distribuídas em delineamento inteiramente ao acaso, com dois tratamentos (ambiente climatizado, AC) com temperatura de 26ºC e ambiente sem climatização (ASC, 32oC) e seis repetições de 25 aves. Ajustaram-se equações alométricas em função do peso em jejum (PJ) para as variáveis: peso do peito (PPEI), coxa (PCX), sobrecoxa (PSCX), asa (PASA), coração (PCOR), fígado (PFÍG), moela (PMOE) e intestino (PINT). Para comparar os "b" das partes e dos órgãos das aves mantidas nos diferentes ambientes, realizaram-se testes de paralelismo. Não houve diferença entre os "b" em nenhuma das partes e dos órgãos das codornas mantidos no ambiente AC ou no ASC. Observou-se que os PPEI e os PSCX apresentaram crescimento heterogônico positivo (b>1), os PCX crescimento isogônico (b=1), os PASA e os órgãos crescimento heterogônico negativo (b<1) em relação ao PJ. Os "b" que descrevem o crescimento das partes e dos órgãos de codornas de corte mantidas nos diferentes ambientes não são influenciados. O peso do peito e o da sobrecoxa apresentaram crescimento tardio, a asa e os órgãos (coração, fígado, moela e intestino) crescimento precoce, e o peso da coxa apresentou crescimento proporcional em relação ao peso em jejum.(AU)

This study was carried out to compare the allometric coefficients (b) that describe the cuts and organs' growth of quails kept in different thermal environments. Three hundred meat quails were distributed in a completely randomized design with two treatments (climatized environment (CE) with 26°C of ambient temperature and environment without climatization (EWC, 32°C)) and six replicates of 25 birds. Allometric equations based on weekly fasting weight (WF) for the breast weight (BW), thigh (TW), drumstick (DW), wing (WW), heart (HW), liver (LW) gizzard (GW) and intestine (IW) were performed. To compare the "b" of the cuts and organs parallelism tests were carried out. There was no difference between the "b" in any cuts and organs of quails kept in CE or EWC environments. We observed that the BW and DW showed positive heterogonic growth (b>1), TW isogonic growth (b=1), and WW and organs negative heterogonic growth (b<1) in relation PJ. The "b" that describes the growth of cuts and organs of quails kept in CE or EWC environments are not affected. The breast and drumstick presented late growth, the wing and the organs early growth, and the thigh showed a proportional increase with the fasting weight.(AU)

Níveis nutricionais de cálcio para aves de corte ISA label criadas sob semiconfinamento / Dietary calcium levels for ISA label broilers raised in semi-confined system

Determinaram-se os níveis nutricionais de cálcio (Ca) para aves, machos e fêmeas, da linhagem ISA Label, nas fases inicial (um a 28 dias), crescimento (28 a 56 dias) e final (56 a 84 dias). Foram realizados três ensaios, um para cada fase, e, em cada ensaio, 480 aves com idade correspondente à fase de criação foram alojadas em 24 unidades experimentais com áreas de abrigo e de pastejo. Foi utilizado delineamento inteiramente ao acaso, em esquema fatorial 4x2 (Ca e sexo), totalizando oito tratamentos com três repetiç ões de 20 aves. Avaliaram-se: ganho de peso (GP); consumo de dieta (CD); conversão alimentar (CA); teores de fósforo (PT), de cálcio (CaT) e de cinzas na tíbia (CT) e resistência à quebra óssea (RQO). Na fase inicial, recomenda-se 1,16 por cento de Ca na dieta, para aves de ambos os sexos, na fase de crescimento, 0,78 e 0,88 por cento de Ca para machos e fêmeas, respectivamente, e, na fase final, 0,69 por cento de Ca na dieta para ambos os sexos.

The nutritional calcium (Ca) levels were determined for ISA Label broilers in the starter (1 to 28 days), growing (28 to 56 days), and finishing (56 to 84 days) phases. Three trials were conducted, one for each phase and in each trial, 480 birds with age corresponding to the phase were housed in 24 experimental units with shelter and pasture areas. The experimental design was completely randomized in a factorial arrangement of 4x2 (Ca levels and sex), totaling eight treatments with three replicates of 20 birds. Body weight gain (BWG); feed intake (FI); feed per gain (FG); contents of phosphorus (TP), calcium (TCa) and ash (TA) in tibia; and bone breaking strength (BSB) were evaluated. At the starter phase, 1.16 percent of Ca is recommended in the diet for birds of both sexes. At the growing phase, 0.78 and 0.88 percent of Ca for males and females, respectively, are recommended and at the finishing phase, the level of 0.69 percent of Ca is recommended in diet for both sexes.

Exigências de lisina digestível para aves de corte da linhagem ISA Label criadas em semiconfinamento / Digestible lysine requirements for ISA Label broilers reared in free-range system

Foram realizados três experimentos para determinar as exigências de lisina digestível para aves da linhagem ISA Label, de ambos os sexos, criadas em semiconfinamento durante as fases: inicial (1 a 28 dias), de crescimento (28 a 56 dias) e final (56 a 84 dias). Em cada experimento, foram utilizadas 480 aves, alojadas em 24 piquetes, cada um contendo abrigo coberto de 3,13m² e área de pastejo de 72,87m². O delineamento experimental utilizado foi o inteiramente ao acaso, em esquema fatorial 4x2 (níveis de lisina e sexo) com três repetições de 20 aves cada. Os níveis de lisina digestível avaliados foram: 0,850; 0,970; 1,090 e 1,210 por cento na fase inicial; 0,750; 0,870; 0,990 e 1,110 por cento na fase de crescimento e 0,640; 0,760; 0,880 e 1,000 por cento na fase final. Foram mensuradas as variáveis de desempenho, característica de carcaça, deposição de proteína e gordura corporal, peso e teor de proteína das penas. Com base nos resultados de desempenho, recomendam-se 1, 041; 1,006 e 0,760 por cento de lisina digestível em rações para aves ISA Label nas fases inicial, de crescimento e final, respectivamente.

Three assays were carried out to determine digestible lysine requirement for ISA Label, both genders, in free-range system on starter (1 to 28 days), growing (28 to 56 days) e finishing phases (56 to 84 days). A total of 480 birds were distributed into 24 pens, each one composed by shelter (3.13m²) and pasture (72.87m²). The experimental design was a completely randomized in factorial arrangement (four levels of lysine and two genders) with three replicates of 20 birds. The digestible lysine levels were 0.85, 0.97, 1.09, and 1.21 percent for starter; 0.75, 0.87, 0.99, and 1.11 percent for growing; and 0.64, 0.76, 0.88, and 1.00 percent for finishing phases. The analyzed parameters were performance, carcass yield, protein and fat deposition, weight, and protein in the feathers. Based on bird performance the estimated digestible lysine level, was 1.041, 1.006, and 0.760 percent for the starter, growing and finishing phases, respectively.