Glicerina bruta em suplementos para novilhas mestiças em pastagens

• Autor(a) principal: Almeida, Vitor Visintin Silva de
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1784
• topic: Glicerina bruta; Digestibilidade; Desempenho; Consumo; Pastagem; Suplementação; Crude glycerine; Digestibility, Performance, Consumption, Pasture, Supplemental; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA

The objective was to evaluate the effect of the use of crude glycerin supplementation in heifers reared on pasture on intake, digestibility and performance, check the chemical composition and fatty acids in beef heifers raised on pasture, to investigate correlations between consumption and deposition fatty acids in the carcass of calves raised on pasture; evaluate the ingestive behavior in the transition period drywater and water, check the economic responses to the inclusion of crude glycerin in the diet. 36 heifers were used crossbred Holstein x Zebu, with initial average weight of 301.5 kg, distributed in a completely randomized design with four treatments and nine replicates per treatment. The animals were kept in pasture production system in Brachiaria brizantha cv. Marandu in rotational stocking during the dry period of transition waters and waters. The treatments tested were 0.0, 3.33, 6.66 and 9.99% crude glycerin inclusion in the total dry matter in replacement of corn, provided a level of 0.7% PC. The intakes of DM and nutrients of the experimental diets were not influenced by the inclusion of crude glycerin, except for the consumption of EE and NFC. The digestibility of DM and nutrients of the experimental diets were not influenced by the inclusion of crude glycerin. The crude glycerin did not affect animal performance, which showed a mean value of 649 g/day. The thickness of fat in the carcass showed increased linearly with the addition of glycerin in the diet. The concentrations of moisture, ash and protein the Longissimus dorsi showed no difference with the addition of glycerin. The total fat content of meat was increased with the addition of glycerin in the diet. The deposition of fatty acids in meat Daisy (17:00), 8- heptadecenóico (17:01), vacênico (18:1 n-7t) and CLA (18:2 c9-t11-) increased, while the pentadecenóico (15 : 01) decreased with the inclusion of glycerol in the diet. The other fatty acids were not altered by the addition of glycerin. The total content of saturated fatty acids (SFA), unsaturated (UFA), monounsaturated (MUFA), polyunsaturated (PUFA), n-6 fatty acids, fatty acids n-3 PUFA ratio: SFA and n-6: n-3 were not affected. The consumption of oleic acid (18:1 n9) correlated with the deposition of acids 12:0, 14:1, 15:0 and 17:0 moderately positively and negatively with acid 15:1. The deposition of the fatty acid 18:1 n7t moderately correlated with almost all the acids in the diet except 14:0, 16:0, 16:1, 17:0 and SFA. Differently than the 18:2 n6 was correlated only with 16:0, 16:1, SFA and PUFA/SFA. The c9t11 18:2 (CLA) showed moderate correlation with almost all fatty acids in the diet. Since the correlation was negative for acids 14:0, 15:0, 18:3 n3, 20:1, 20:1 n9, PUFA, PUFA/SFA and n3. The inclusion of crude glycerin decreases the time of grazing and trough, and increased leisure time animals in the transition period dry water. Rumination was influenced quadratically. The power (min/kg DM and NDF) was reduced, while ruminating (min /kg DM and NDF) had a quadratic effect with the addition of glycerin. The variables of time spent for each ruminated cake, cake and numbers chews per day were not affected. The number of cakes per day showed a quadratic effect. The numbers of grazing periods, leisure, rumination and troughs were not influenced by the inclusion of crude glycerin, with mean values of 15.1, 24.9 and 13.3 and 3.71 times per day, respectively. The efficiency of feeding and rumination (kg / hour of DM and NDF) increased with the inclusion of crude glycerin in the diet. The inclusion of crude glycerin promotes improvement in the efficiency of feeding and rumination in grazing heifers. In the period of time spent on water supply (minutes/kg DM and NDF) was not affected, while ruminating (min/kg DM and NDF) was reduced with the addition of glycerin. The variable number of cakes per day and chews per day had a linear effect with the levels of inclusion. The time taken for each cake ruminated and the number of chews per bolus was not influenced. Intake of DM and NDF (g /meal) had a quadratic effect and efficiency of power expressed per kg DM and NDF per hour was not influenced by inclusion of glycerol in the diet. The efficiencies of rumination was improved with the addition of glycerin. The inclusion of crude glycerin in diets affects some parameters of the feeding behavior of heifers on pasture. Meat production was not modified by the inclusion of glycerol in the diet. The inclusion of glycerol caused a reduction of up to 14.93% in the price of the concentrate. A significant increase in the total balance which increased from 3.76 to 91.89 reais / ha with the addition of glycerin. The inclusion of crude glycerin in the supplement was able to raise the net present value and internal rate of return, proving to be an alternative to lower the production cost of supplemented animals on pasture.