Glycerin is a major co-product resulting from biodiesel production, and it has been proposed as a highenergy source for use in swine diets. However, it is necessary to determine the nutritional value of neutral semi-purified glycerin (NSPG). In this study two experiments were carried out to determine the nutritional value, evaluated the performance and economic feasibility of starting piglets fed on neutral semi-purified glycerin. A digestibility trial (Experiment I) was conducted using 30 crossbred barrows with an initial average body weight of 42.91±1.58 kg. The glycerin levels used in the digestibility assay were 4, 8, 12 and 16% of the basal diet (corn + soybean meal based). The digestible energy (DE) and metabolizable (ME) energy values of glycerin were estimated by regression of DE and ME (kcal/kg) intake associated with glycerin vs. glycerin intake (kg). The values (as-fed-basis) of DE and ME (kcal/ kg) obtained were 3,298 and 2,531, respectively. In Experiment II, 100 piglets (50 gilts and 50 barrows) with BW = 15.14±0.06 to 30.28±0.65 were allotted in a randomized design using four inclusion levels (3.5, 7.0, 10.5 and 14%) of NSPG. There were ten replicates with two piglets per experimental unit. Additionally, a control diet containing no glycerin (0%) was formulated. The results show it is feasible to use up to 14% NSPG in piglet feed without impairing performance and plasma chemistry. Key words: Biodiesel, digestibility, glycerol, performance ResumoA glicerina é o principal coproduto da produção do biodiesel, e é proposta sua utilização como uma fonte de alto potencial energético na alimentação de suínos. No entanto é necessário determinar seu valor nutricional da glicerina semi-purificada neutralizada (GSPN). Neste estudo, foram conduzidos dois experimentos com o objetivo de determinar o valor nutricional, avaliar o desempenho e a viabilidade econômica de leitões alimentados com GSPN. O ensaio de digestibilidade (Experimento I) foi conduzido utilizando 30 suínos mestiços com peso vivo médio inicial de 42,91 ± 1,58 kg. Os níveis de substituição da ração referência pela glicerina foram 4, 8, 12 e 16%. Os valores de energia digestível (ED) e metabolizável (EM) das glicerinas foram estimados pela análise de regressão do consumo de ED e EM (kcal/kg) associada com a glicerina vs. consumo de glicerina (kg). Os valores de ED e EM (kcal/ kg), na matéria natural, obtidos foram de: 3.298 e 2.531 kcal/kg respectivamente. No experimento II, 100 leitões (50 fêmeas e 50 machos cadastros) com peso vivo inicial de 15,14±0,06 a 30,28±0,65 kg) foram distribuídos em delineamento de blocos casualizados, com quatro níveis de inclusão (3,5; 7,0;

-Two experiments were carried out to determine the nutritional value and to evaluate performance of piglets fed two types of crude glycerine (CG), which were made from vegetable oil (CGS) and a mix of animal fat + % soybean oil (CGA). In experiment I, a digestibility assay was conducted using 32 crossbred piglets (19.20±1.52 kg). The experimental unit consisted of one pig, with a total of four experimental units per diet. The glycerine levels used in the digestibility assay were 4, 8, and 12% of the basal diet (corn + soybean based). The digestible (DE) and metabolizable energy (ME) values of glycerine were estimated by regression of DE and ME intake (kcal/kg) vs. glycerine intake (kg). The values (as-fed basis) of DE and ME (kcal/kg) obtained were: CGS = 5,070 and 4,556; CGA = 5,143 and 4,488, respectively. The results indicate that these two types of glycerine are a highly-available energy source for the feeding of piglets (15-30 kg). In experiment II, 90 piglets (BW = 15.18±0.67 to 30.28±1.68 kg), were allotted in a completely randomized design in 2 × 4 factorial arrangement, with of two types of crude glycerine (CGS and CGA) and four inclusion levels (3, 6, 9, and 12%). Five experimental units (pens with two pigs) were used for each level of crude glycerine, resulting in five replicates per treatment in the diet. Additionally, a control diet containing no glycerine (0%) was formulated. There was no interaction between levels of CG and types of crude glycerine, and the regression analysis indicates no effects of crude glycerine inclusion on performance and plasma variables. The results suggest that it is feasible to use up to 12% of both tyes of crude glycerine (obtained from soybean oil and mixed) in the diet for piglets without impairing performance, in addition to promoting a reduction of about 11% in the cost with feeding.

This study aimed to assess the effects of β-mannanase supplementation in metabolizable energy (ME)-reduced diets containing xylanase-phytase on performance, fecal score, blood biochemical and immunological profile, apparent total tract digestibility (ATTD), digesta passage rate, fecal microbiome, carcass traits and meat quality in finisher pigs (n = 40 entire male hybrid, 26.0 ± 0.9 kg) randomly assigned to 1 of 4 dietary treatments: a control diet containing isolated phytase and xylanase valued at 40 kcal of ME/kg (CD0), CD0 + β-mannanase (0.3 g/kg valued at 30 kcal of ME/kg) (CD70), CD0 + β-mannanase (0.3 g/kg valued at 45 kcal of ME/kg) (CD85), and CD0 + β-mannanase (0.3 g/kg valued at 60 kcal of ME/kg) (CD100), with 10 pen replicates. Pigs fed CD0 diet showed (P = 0.002) greater ADFI. However, pigs fed CD0 diet showed (P = 0.009) lower G:F than those provided CD70 or CD85 diets. A greater (P < 0.001) superoxide dismutase concentration was observed in pigs fed CD70 diet. Pigs fed CD85 diet showed (P = 0.002) greater digestible protein than pigs fed CD0 or CD100 diets. Pigs fed CD70 diet showed an increase of 11.3% in digestible protein than those fed CD0 diet. In addition, greater (P < 0.001) digestible energy was observed in pigs fed CD85 diet. Pigs fed CD0 or CD100 diets showed greater (P < 0.05) Firmicutes:Bacteroidota ratio than those fed CD85 diet. The Muribaculaceae was more abundant (P = 0.030) in pigs fed CD70 diet than in those fed CD0 diet. The Prevotella was more abundant (P = 0.045) in pigs fed CD85 diet than in those fed CD100 diet. In conclusion, β-mannanase supplementation in diets containing xylanase-phytase allows reducing 85 kcal of ME/kg because it improves gain to feed ratio, energy and protein usage, and backfat thickness without metabolic and intestinal ecosystem disorders in finisher pigs.

Two experiments were carried out aiming to determine the nutritional value and to evaluate performance, carcass traits and economic feasibility of growing-finishing pigs fed on two types of crude glycerine (CG) which were made from vegetable oil (CGS), and mixed of animal fat + soybean oil (CGA). In Experiment I, a digestibility assay were carried out using 32 (24 test diet and 8 basal diet) cross breed pig (45.08 ± 4.11 kg). The experimental unit consisted of one pig, with a total of four experimental units per diet. Glycerine levels used in the digestibility assay were 6, 12, and 18% of the basal diet (corn + soybean meal based). The values (as-fed-basis) of DE and ME (kcal/kg) obtained were: CGS= 5,040 and 4,481; CGA= 5,234 and 4,707, respectively. In the Experiment II, 63 pigs, were allotted in a completely randomized design in 2 x 4 factorial scheme, with two types of crude glycerine (CGS and CGA) and four inclusion levels (3, 6, 9, and 12%). Additionally, it was formulated a control diet containg no glycerine (0%). There was no interaction (P≥0.05) among levels of CG and types of glycerine sources, and the regression analysis indicates no effects (P≥0.05) of crude glycerine inclusion on performance and carcass traits (backfat thickness and loin depth). The results suggest that it is feasible to use up to 12% of both crude glycerine (made from soybean oil and mixed) on growing-finishing pigs diet, without impairing performance and carcass traits, besides providing a reduction of about 11% on feeding cost. Key words: Biodiesel, co-product, digestibility, glycerol ResumoForam conduzidos dois experimentos com o objetivo de determinar o valor nutricional e avaliar o desempenho, característica de carcaça e viabilidade econômica de suínos em fase de crescimento e terminação alimentados com rações contendo dois tipos de glicerinas brutas: GBV -oriunda de óleo vegetal (soja) e GBM -mista, oriunda de gordura animal e óleo de soja. No Experimento I, foi conduzido um ensaio de digestibilidade com 32 (24 rações testes e 8 ração referência) suínos (45,08 ± 4,11 kg) mestiços. A unidade experimental consistiu-se de um suíno, totalizando quatro unidades experimentais por ração. Os níveis de substituição da ração referência pela glicerina foram 6, 12 e 18%. Os valores de ED e EM (kcal/kg), na matéria natural, obtidos foram: GBV= 5.040 e 4.481 e GBM= 5.234 e 4.707, respectivamente. No Experimento II, foram utilizados 63 suínos, distribuídos em delineamento inteiramente casualizados, em esquema fatorial 2 x 4, sendo dois tipos de glicerina bruta (GBV e GBM) e quatro níveis de inclusão (3, 6, 9 e 12%). Adicionalmente, foi formulada uma ração testemunha, não contendo glicerina (0%). Não houve interação (P≥0,05) entre os níveis de inclusão e o tipo da glicerina bruta. A análise de regressão indica que não houve efeito (P≥0,05) do nível de inclusão das glicerinas brutas sobre o desempenho e característica de carcaça (espessura de toucinho

Três experimentos foram conduzidos com o objetivo de avaliar o efeito da adição de complexo enzimático (CE) sobre o valor nutritivo da casca de soja utilizada na alimentação de suínos na fase inicial. O complexo enzimático utilizado continha α-galactosidase, β-glucanase, galactomananase e xilanase. No experimento 1, determinou-se a digestibilidade da casca de soja com complexo enzimático (0, 200 e 300 mg/kg) em leitões com peso inicial de 22,49 ± 1,73 kg. Nenhum dos níveis de complexo enzimático afetou a digestibilidade da casca de soja. Assim, realizou-se outro ensaio de digestibilidade (experimento 2) com dois níveis (0 e 600 mg/kg) de complexo enzimático e, novamente, a adição de complexo enzimático (600 mg de CE/kg de ração) não melhorou a digestibilidade da casca de soja. No experimento para análise do desempenho (experimento 3), foram utilizados 60 leitões, machos castrados e fêmeas com peso inicial de 15,07 ± 1,69 kg, distribuídos em delineamento em blocos casualizados, com cinco tratamentos, seis repetições e dois animais por unidade experimental. Avaliaram-se uma ração à base de milho e farelo de soja e outras quatro rações isonutritivas com 15% de casca de soja e complexo enzimático nos níveis 0, 200, 400 ou 600 mg/kg. O consumo diário de ração e o ganho de peso diário foram menores entre os animais alimentados com a ração contendo casca de soja em comparação àqueles alimentados com a ração-referência. Entretanto, a conversão alimentar melhorou de forma linear com inclusão do complexo enzimático (200, 400 e 600 mg/kg). O uso do complexo enzimático não afeta a digestibilidade da casca de soja, mas melhora a conversão alimentar de leitões (15-30 kg) alimentados com dietas contendo 15% de casca de soja.