Cana-de-açúcar tratada com óxido de cálcio em dietas para ovinos, caprinos, novilhas e vacas em lactação

• Ano de defesa: 2008
• Autor(a) principal: Carvalho, Gleidson Giordano Pinto de
• Orientador(a): Garcia, Rasmo
• Banca de defesa: Pereira, Mara Lucia Albuquerque , Paulino, Mário Fonseca
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Consumo; Óxido de cálcio; Digestibilidade
• Palavras-chave em Inglês: Intake; Calcium oxide; Digestibility
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PASTAGEM E FORRAGICULTURA
• Link de acesso: http://locus.ufv.br/handle/123456789/1720

The present work was developed by the conduction of four experiments, which generated information that will be presented in the form of eleven chapters. Initially, it is important to emphasize that the sugar cane used in the experiments that will be described below was treated by a 24 hours period with calcium oxide (CaO) doses of 0; 0.75; 1.5 and 2.25% (in natural matter basis), with the treatment without CaO addition (0%) constituted by sugar cane in natura cut and offered fresh to the animals every day. In the first chapter it was evaluated the nutrients intake, apparent digestibility and the effect of days of total collection (two and four days) in the estimative of apparent digestibility in sheep fed with diets containing sugar cane treated with calcium oxide (CaO). The objective was also to compare the DM and TDN intakes observed with that estimated based on NRC (2006). Eight castrated male Santa Inês sheep, with 16.6 kg average body weight were used, distributed in two 4 x 4 Latin squares, with four experimental periods of 14 days each. The intake and digestibility evaluation was realized at the last four days of each period. The diets were formulated to be isonitrogenous (14% crude protein), presented 70% sugar cane with 0; 0.75; 1.5 or 2.25% of CaO, corrected with 1% urea and 30% of concentrate. The sugar cane with CaO addition doses was chopped, treated and being offered to the animals after 24 hours of storage. The sugar sugar cane with CaO promoted increase of DM, OM, CP, NDF, NDFap, TC, NFCap and TDN intake (kg/day) in relation to the cane in natural, being the same behavior observed for the intake (% BW). There was lineal increase of the intake of DM sugar cane with CaO. The DM and NFCap digestibility reduced linearly. On the other hand the digestibility of DM and NDF, and TDN lineal decrease. It was observed a under estimative of DM and TDN intakes estimated by NRC (2006). The sugar cane chemical treatment with CaO increase of intake but does not improve nutrients digestibility. Two days of total fecal collection are sufficient to estimate the total apparent digestibility in sheep. In the second chapter it was evaluated the ingestive behavior, the nitrogen balance, the urea concentrations in urine and plasma and the microbial protein synthesis in sheep fed diets containing sugar cane treated with CaO. The experimental design and the diets were similar to that reported in the first chapter. The times expended in feeding, ruminating and idle (min/day) were not affected by CaO addition to sugar cane. As excreções de nitrogênio (N) nas fezes e urina aumentaram com as doses de CaO, entretanto, o N retido (g/dia) não foi afetado. Nitrogen (N) feces and urine excretion increased with CaO doses, however, the retained N (g/day) was not affected. Urine and plasma urea concentration and daily urea and purine derivatives excretion were not altered by CaO addition. With the exception of microbial efficiency (g CP/kg TDN) that it was larger in the in natural sugar cane, microbial purine excretion and N and microbial protein synthesis are not affected by addition of CaO to sugar cane, in diets to Santa Inês sheep. In the third chapter it was evaluated the intake, the apparent digestibility of nutrients and the effect of days of total collection (two and four days) in apparent digestibility estimative in goats fed diets containing sugar cane treated with calcium oxide (CaO). The objective was also to compare the DM and TDN intake observed with that estimated by NRC (2006). Eight castrated male Saanen goats, with 22.6 kg average body weight were used, distributed in two 4 x 4 Latin squares, with four experimental periods of 14 days each. The intake and digestibility evaluation was realized at the last four days of each period. The diets were formulated to be isonitrogenous (14% crude protein), presented 70% sugar cane with 0; 0.75; 1.5 or 2.25% of CaO corrected with 1% urea and 30% of concentrate. Most of the variables related with the intake was larger in the treatment with sugar cane with CaO in relation to the in natural sugar cane. The intakes of DM, DMi, OM, CP, NDFi, TC, NFCap and TDN (kg/day) and DM, OM and TDN (% BW) increased with CaO doses added to the sugar cane. The DM, CP and NFCap coefficient of digestibility they were smaller in the treatment with sugar cane with CaO in relation to the in natural sugar cane. It was verified reduced linearly of coefficient of digestibility NDF and effect quadratic of the EE e NFCap. It was observed sub estimative of DM and TDN intakes estimated by NRC (2006). The CaO use in sugar cane treatment increase of intake but did not improve nutrients digestibility. Two days of total feces collection are sufficient to estimate the total apparent digestibility in goats. In the fourth chapter it was evaluated the ingestive behavior, nitrogen balance, urine and plasma urea concentrations and microbial protein synthesis in goats fed with diets containing sugar cane treated with CaO. The design and experimental conditions were similar to that related in the third chapter. The times in feeding, ruminating (min/day; min/kg DM and min/kg NDF) and idle (min/day) did not show effect in function of CaO doses added to sugar cane. Except for feeding time in min/kg DM, that reduced linearly, the times expended feeding (min/day; min/kg DM and min/kg NDF), ruminating and in idle (min/day, min/kg DM and min/kg NDF) were not affected by CaO addition to sugar cane. To chewing activities, it was verified effect only to total time expended in min/kg DM. The feeding and ruminating efficiency were not affected by CaO addition to sugar cane. It was verified a reduction (P<0.05) in average time spent in each feeding period. The nitrogen balance, urine and plasma urea concentrations and urine urea excretion did not show effect in function of CaO doses added to sugar cane. The allantoin (% of total purines) increased and the uric acid reduced in the treatments with sugar cane treated with CaO in relation to the in natural cane. The microbial production and efficiency are not affected by CaO addition to sugar cane, in diets for growing goats. In the fifth chapter it was studied the effect of intervals among observations in the estimative of sheep and goats ingestive behavior. The animals (chapters 1 and 3) were observed 24 hours per day, at the end of each experimental period, in intervals of 5, 10, 15 and 20 minutes. The effect of intervals among observations on the behavior variables was evaluated by Dunnett test, in independent manner to fixed effects of treatment and Latin squares. As far as to sheep as to goats, lesser values (P<0.05) to number of periods (no/day) and greater values (P<0.05) to time expended for period of feeding, ruminating and idle activities in 10, 15 and 20 minutes were verified. The DM and NDFap average intake per feeding period also presented low (P<0.05) in 10, 15 and 20 minutes intervals compared to that of 5 minutes. The use of the intervals of 10, 15 and 20 minutes in ingestive behavior evaluation of sheep and goats does not alter the time spent in feeding, rumination and idle (P>0.05), though, conduct to overestimated estimative of average time expended in each activity period and under estimated estimative of number of feeding, ruminating and idle periods. It is recommended the use of the 5 minutes interval among observations for the ingestive behavior studies with sheep and goats. In the sixth chapter the objective was to evaluate the long time vice (LTV) of the internal markers indigestible dry matter (iDM) and indigestible neutral (iNDF) and acid detergent fiber (iADF) in sheep and goats. Feed, scraps and feces samples (chapters 1 and 3) were submitted to in situ ruminal incubation, during 240 hours, for the estimative of the markers concentration. The ratio between intake and excretion of markers was realized by adjustment of simple linear regression model, in independent way from fixed effects of treatments and Latin squares. Both in sheep and goats, complete recovered of iDM and iNDF markers was verified (P>0.05), indicating absence of LTV for these markers. For iADF, the recovery was not complete, verifying LTV of -9.12% (P<0.05) in sheep evaluation and - 3.02% (P<0.05) in the evaluation realized with goats. In the seventh chapter it was evaluated the intake and apparent digestibility of nutrients in dairy heifers fed diets containing sugar cane treated with calcium oxide (CaO). It was also objective to evaluate the prediction efficiency by NRC (2001) system of equations of the DM intake and feeds energetic value. Twenty Holstein-zebu crossbred dairy heifers, with 200 kg average initial body weight were used, distributed in a completely randomized design, with four treatments and five repetitions. The treatments were constituted of four doses of CaO (0; 0.75; 1.5 and 2.25%) used in sugar cane treatment. The experimental period was of 21 days, with intake and digestibility evaluated at the last seven days. The diets were formulated to be isonitrogenous (14% crude protein), presented 71% sugar cane with 0; 0.75; 1.5 and 2.25% CaO corrected with 1% of urea and ammonium sulfate (9:1) mixture and 29% of concentrate. The DM, EE, NDF, NDFap, iNDF, TC and NFCap intakes (kg/day) were not affected by CaO addition to sugar cane. The OM, NDF, NDFap and TDN intakes (% BW) reduced linearly with CaO doses. The OM, NDF, NDFap, TC and NFCap digestibilities and the diets TDN content were not affected. However, the sugar cane treatment with CaO caused reduction of DM and CP digestibility. The equations proposed by NRC (2001) underestimated the DM and TDN intakes and digestible CP and NFC and overestimated that of digestible NDF. The sugar cane treatment with CaO do not improve the nutrients intake and digestibility in dairy heifers. The equations proposed by NRC (2001) to estimate the DM intake and feed s energetic value are not applied to tropical conditions. The eighth chapter it was evaluated the ingestive behavior, the nitrogen (N) balance, the urea concentrations in urine and plasma and the microbial protein synthesis in heifers fed diets containing sugar cane treated with CaO. The design and experimental conditions were similar to that reported in the seventh chapter. There was linear reduction of the number of daily mastication s (P<0.05) and of total time of mastication (min/day) (P<0.01). The rumination efficiency (number of bolus/day) had linear negatively with the CaO doses added to sugar cane. The animals N balance was also affected by the CaO doses added to sugar cane, registering reduction also of the intake as of the digested and retained N quantity. The retained N content (% of N ingested and digested) also decreased linearly (P<0.01). The use of the CaO doses of up to 2.25% in sugar cane treatment did not affected the urine and plasma urea concentrations, the urine urea excretion and the microbial protein synthesis in dairy heifers. In the ninth chapter it was evaluated the intake, apparent digestibility of nutrients and milk production and composition of dairy cows fed diets containing sugar cane treated with CaO. It was also objective to evaluate the prediction efficiency by NRC (2001) system of equations of the DM intake and feeds energetic value. Sixteen crossbred dairy cows were used, distributed in a completely randomized design, with four treatments and four repetitions. The treatments were constituted of four CaO (0; 0.75; 1.5 and 2.25%) doses added to the sugar cane. The experimental period was of 21 days, with the intake and digestibility evaluated at the seven last days. The diets were formulated to be isonitrogenous (13% crude protein), presented 85% sugar cane with 0; 0.75; 1.5 or 2.25% CaO corrected with 1% of urea and ammonium sulfate (9:1) mixture and 15% of concentrate. The DM, OM, NDF, NDFap, TC and NFCap intakes (kg/day) were not affected by CaO addition to sugar cane. With the exception of the EE digestibility, that it didn't present significant effect (P>0.05), the other nutrients digestibility (DM, OM, CP, NDF, NDFap, TC and TDN) had quadratic behavior. Milk production and DM efficiency were not affected by sugar cane addition (P>0.05). Milk fat, protein, lactose, total solids and defatted dry extract contents (kg/day) were not altered by CaO addition to sugar cane (P>0.05). The equations proposed by NRC (2001) overestimate the DM and CP intakes and digestible NDF and NFC and underestimate that of digestible EE and of TDN. The use of CaO chemical treatment of sugar cane does not promote significant improve in nutrients intake and digestibility neither in cows milk production and composition. The equations proposed by NRC (2001) to estimate the DM intake and feeds energetic value do not apply to tropical conditions. In the tenth chapter it was evaluated the ingestive behavior, nitrogen (N) balance, urine and plasma urea concentrations and microbial protein synthesis in dairy cows fed diets containing sugar cane treated with CaO. The design and experimental conditions were similar to that reported in the ninth chapter. The ingestive behavior was realized during two consecutive days, with the observations done at five minutes intervals. The rumination (min/day) reduced linearly (P<0.05). The N retention had quadratic behavior with the CaO addition to sugar sugar cane. The excretions of nitrogen in the urine and in the milk (g/day) were not affected by CaO addition to sugar cane. The urine, plasma and milk urea concentrations and the urine and milk urea excretions were not affected by CaO doses. There was no effect of the treatments on urine and milk allantoin excretions, uric acid in urine and excretion of total purines. The CaO addition to sugar cane does not influence the microbial synthesis in dairy cows. In the eleventh chapter it was studied the effect of intervals among observations in the estimative of ingestive behavior in dairy heifers and cows. The animals (chapters 7 and 9) were observed, 24 hours a day, at the end of the experimental period, in 5, 10, 15 and 20 minutes intervals. The effect of intervals among observations on the behavioral variables was evaluated by the Dunnett test, in independent way from fixed effects of CaO doses and Latin squares. Both for heifers as for cows, lesser values (P<0.05) were verified for number of periods (no/day) and greater (P<0.05) for average time spent per period of activities of feeding, rumination and idle at the 10, 15 and 20 minutes intervals. The average DM and NDFap intake per feeding period was also lesser (P<0.05) at 10, 15 and 20 minutes intervals. The intervals among observations of 10, 15 and 20 minutes underestimate the number of periods (no/day) and overestimate the average time spent per feeding, rumination and idle period (min) in dairy heifers and cows, conducting to fallacy estimates. It is recommended the use of the 5 minutes interval in studies of cattle ingestive behavior evaluation.