ABSTRACT: The objective was to evaluate the impact of producing piglets fed diets with different crude protein (CP) levels through life cycle assessment and experimental data. In Trial I (performance), 28 crossbred barrow piglets, with an initial average weight of 15.3 ± 1.15 kg were divided into a randomized block design with four treatments, seven replications and one animal per experimental unit. In Trial II (nitrogen and phosphorus balance), 20 crossbred barrow piglets with an average weight of 21.4 ± 1.62 kg were divided in a randomized block design with four treatments, five replications and one animal per experimental unit. Four experimental feeds were evaluated: HighCP, CP18, CP17 and LowCP, with 19, 18, 17 and 16 % of CP, meeting the requirements of digestible amino acids through industrial amino acid (IAA) addition. From Trial I and II data, the environmental impact was calculated for global warming potential, acidification potential, eutrophication potential, cumulative energy demand, terrestrial ecotoxicity and land occupation (LO). Total nitrogen excretion decreased by 0.226 g d−1 for each 1 g of reduction on daily nitrogen intake. However, there was no statistical difference (p > 0.05) among experimental treatments for all impact categories. For LO, there was a reduction (p = 0.078) of impact with CP reduction, which was 8 % lower with the LowCP diet, in comparison with HighCP. Dietary CP reduction for piglets from 15 to 30 kg, through IAA supplementation, reduced the environmental impact under LO, considering soybean meal from southern Brazil and observed individual data of performance and excretion.

ABSTRACT: The chemical composition of corn is variable and the knowledge of its chemical and energetic composition is required for an accurate formulation of the diet. This study aimed to determine the chemical composition, that is, dry matter (DM), mineral matter (MM), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), crude protein (CP), gross energy (GE) and energetic values of different varieties (batches) of corn and validate mathematical models to predict the metabolizable energy values (ME) of corn for pigs using near infrared spectroscopy (NIRS). Corn samples were scanned in the spectrum range between 1,100 and 2,500 nm, the model parameters were estimated by the modified partial least squares (MPLS) method. Ten prediction equations were inserted into the NIRS and used to estimate the ME values. The first degree linear regression models of the estimated ME values in function of the observed ME values were adjusted. The existence of a linear ratio was evaluated by detecting the significance to posterior estimates of the straight line parameters. The values of digestible energy and ME ranged from 3,400 to 3,752 and 3,244 to 3,611 kcal kg−1, respectively. The prediction equations, ME1 = 4334 – 8.1MM + 4.1EE – 3.7NDF; ME2 = 4,194 – 9.2MM + 1.0CP + 4.1EE – 3.5NDF; and ME7 = 16.13 – 9.5NDF + 16EE + (23CP × NDF) – (138MM × NDF) were the most adequate to predict the ME values of corn by using NIRS.

ABSTRACT This study was carried out to evaluate the effect of different levels of standardized ileal digestible (SID) methionine + cystine (Met+Cys) and vitamin B6 supplementation on the performance, blood variables, and gene expression of enzymes involved in methionine metabolism in female pigs between 75 and 100 kg. Fifty six female pigs were used (Talent × Topigs 20), averaging 75.06±1.68 kg in initial weight, allotted in a completely randomized block design arranged in a 2 × 4 factorial scheme, composed of two vitamin B6 supplementation levels (1.58 and 3.58 mg/kg) and four levels of SID Met+Cys (0.370, 0.470, 0.570, and 0.670%), with seven replicates and one animal per experimental unit. No interactions between vitamin B6 supplementation and SID Met+Cys levels were observed. The levels of SID Met+Cys and vitamin B6 supplementation did not affect animal performance. Triacylglycerols showed a quadratic response to the SID Met+Cys levels, in which the lowest plasma concentration was estimated as 0.575%. Treatments did not affect the expression of the methionine synthase and cystathionine-γ-lyase enzymes or serum homocysteine levels. The SID Met+Cys requirement for female pigs from 75 to 100 kg is equal to or lower than 10.60 g/day, which corresponds to the level of 0.370% Met+Cys in the diet and a relationship 0.48% with the SID lysine.

RESUMO Objetivou-se com este estudo, determinar a composição química, a energia metabolizável aparente (EMA), energia metabolizável aparente corrigida para o nitrogênio (EMAn) e a metabolizabilidade da matéria seca (MS), proteína bruta (PB), extrato etéreo (EE) e fibra em detergente neutro (FDN) do farelo da semente de maracujá (FSM) para codornas. Foram utilizadas 100 codornas de corte (Coturnix coturnix japonica) com 21 dias de idade, distribuídos em um delineamento inteiramente casualizado, com quatro tratamentos, cinco repetições e quatro aves por unidade experimental. Os tratamentos constituíram de diferentes níveis de FSM (4,0; 8,0; 12,0; 16,0%) em substituição a ração referência. Valores metabolizáveis foram determinados por ajuste de equações lineares. O FSM pode ser caracterizado como um alimento alternativo para codornas de corte e seus principais compostos são a energia bruta (5.569 kcal kg-1), PB (11,34%), EE (18,84%) e FDN (50,22%), na matéria natural. Foram ajustadas as equações EMA = 2.976 + 5,877 x (r2 = 0,94) e EMAn = 2.939 + 4,864 x (r2 = 0,95), assim, a EMA e EMAn foram estimadas em 2.976 e 2.939 kcal kg-1, respectivamente. Adicionalmente, foram ajustadas equações para PB, EE, FDN e MS resultando em valores metabolizáveis de 6,35, 17,9, 12,48 e 45,66%, respectivamente. Conclui-se que os principais componentes do farelo da semente de maracujá são a energia bruta, proteína bruta, extrato etéreo e fibra em detergente neutro, e a EMA e EMAn para codornas de corte é de 2.976 e 2.939 kcal kg-1, respectivamente.

SUMMARY The objective of this study was to determine the chemical composition, apparent metabolizable energy (AME), apparent metabolizable energy corrected for nitrogen balance (AMEn) and the metabolizability of dry matter (DM), crude protein (CP), ether extract (EE) and neutral detergent fiber (NDF) of passion fruit seed meal (PFM) for quails. One hundred meat quails (Coturnix coturnix japonica), with 21 days old, allotted in a completely randomized design, with four treatments, five replicates and four animals per experimental unit. The treatments consisted of different levels PFM (4.0, 8.0, 12.0 and 16.0%) that replaced the basal diet (w/w). Metabolizable values were determined by fitting linear equations the PFM can be characterized as an alternative feedstuff for meat quails and the main chemical compounds are gross energy (5,569 kcal kg-1), CP (11.34%), EE (18.84%) and NDF (50.22%), as fed basis. Linear equations were fitted as follow: AME = 2,976 x + 5.877 (r2 = 0.94) and AMEn = 2,939 x + 4.864 (r2 = 0.95), thus AME and AMEn were estimated at 2,976 and 2,939 kcal kg-1, respectively. Additionaly, equations were adjusted for CP, EE, NFD and DM, respectively resulting in a metabolization of 6.35, 17.9, 12.48 and 45.66%. It is concluded that main components of the passion fruit seed meal are gross energy, crude protein, ether extract and neutral detergent fiber and its AME and AMEn for meat quails are 2,976 and 2,939 kcal kg-1, respectively.