CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O objetivo neste estudo foi avaliar a inclusÃo de diferentes fontes de lipÃdeos na dieta de cordeiros sobre o consumo e digestibilidade da matÃria seca (MS), matÃria orgÃnica (MO), proteÃna bruta (PB), extrato etÃreo (EE), fibra em detergente neutro (FDN), carboidratos totais (CT), carboidratos nÃo-fibrosos (CNF), nutrientes digestÃveis totais (NDT) e energia metabolizÃvel (EM); a produÃÃo microbiana; o balanÃo de nitrogÃnio (BN), as excreÃÃes de creatinina e os padrÃes nictemerais do comportamento ingestivo. Foram utilizados 35 ovinos da raÃa Santa InÃs com peso mÃdio inicial de 13,00  1,80 kg, em delineamento experimental em blocos ao acaso, com cinco dietas experimentais (dieta controle, sem suplementaÃÃo; dieta com caroÃo de algodÃo (CAL), com farelo de castanha de caju (FCC), com caroÃo de algodÃo mais farelo de castanha de caju (CALFCC) e com sais de cÃlcio de Ãcidos graxos de cadeia longa (CaAgCl). O consumo de MS (kg/dia, %PC e g/kg0,75) e dos nutrientes (kg/dia) nÃo foram alterados com a inclusÃo de fontes lipÃdicas nas dietas, com exceÃÃo dos consumos de EE, CNF (kg/dia) e FDN (%PC e g/kg0,75). A suplementaÃÃo lipÃdica influenciou a digestibilidade dos nutrientes, de modo que as dietas com CAL apresentaram os menores coeficientes de digestibilidade da MS, MO, FDN e CT (63,89; 64,41; 70,79 e 54,02%, respectivamente), quando comparado à dieta controle. NÃo houve diferenÃa entre as dietas em relaÃÃo ao volume urinÃrio, no entanto as excreÃÃes de creatinina foram influenciadas. O BN nÃo foi alterado com a inclusÃo de lipÃdeos, porÃm as excreÃÃes dos derivados de purina (DP mmol/dia), absorÃÃo dos derivados de purina (abs. DP mmol/dia), produÃÃo de nitrogÃnio microbiano (N mic mmol/dia), proteÃna bruta microbiana (PB mic g/dia) e eficiÃncia de sÃntese de proteÃna microbiana (ESPBmic g/kgNDT) foram afetadas pela adiÃÃo de lipÃdeos dietÃticos, de modo que as menores mÃdias para essas variÃveis foram para a dieta suplementada com CaAgCl (3,48; 2,95; 2,14; 13,40; 21,31 mmol/dia, respectivamente). O tempo de ruminaÃÃo (TR), o nÃmero de mastigaÃÃes merÃcicas (nÂ/dia) e mastigaÃÃes merÃcicas por bolo (nÂ/bolo) foram influenciados de acordo com as fontes lipÃdicas na dieta, de modo que os maiores tempos foram dispendidos para o tratamento CAL (10,14; 61026 e 78,91, respectivamente). Os animais consumiram preferencialmente nos horÃrios que compreenderam os perÃodos de 06:00 Ãs 12:00 e 12:00 Ãs 18:00 hs e ruminaram nos perÃodos que compreenderam os intervalos 18:00 Ãs 24:00 e 24:00 Ãs 06:00 hs. A adiÃÃo de diferentes fontes de lipÃdeos nÃo influencia o consumo de MS e dos nutrientes, com exceÃÃo do consumo de EE e CNF, porÃm influencia os coeficientes de digestibilidade da MS e dos nutrientes. O BN e o volume urinÃrio nÃo sÃo influenciados de acordo com a fonte de lipÃdeos da dieta, contudo as excreÃÃes de creatinina sÃo influenciadas e a produÃÃo microbiana à reduzida quando CaAgcl fazem parte da dieta. A suplementaÃÃo à base de caroÃo de algodÃo influencia os padrÃes nictemerais do comportamento ingestivo em ovinos da raÃa Santa InÃs. / The aim of this study was to evaluate the inclusion of different fat sources in the diet of lambs over the intake and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), total carbohydrates (TC), non-fiber carbohydrates (NFC), total digestible nutrients (TDN) and metabolizable energy (ME), microbial production, nitrogen balance (NB), creatinine excretion and nictemeral pattern of feeding behavior. It was used 35 Santa InÃs sheep with initial body weight of 13.00  1.80 kg. The experimental design was randomized blocks. The experimental diets consisted of five treatments: the control diet without supplementation, added cottonseed (CAL), bran cashews (FCC), cottonseed meal plus cashews (CALFCC) and calcium salts of long chain fatty acids (CaAgCl). DM intake (kg/day, %PC and g/kg0.75) and nutrients (kg/day) did not change according to the inclusion of dietary lipids, with the exception of EE, NFC intake (kg/day) and NDF (%PC and g/kg0.75). The lipid supplementation influenced the nutrients digestibility, so that diets with CAL showed the lowest digestibility coefficients for DM, OM, NDF and CT (63.89, 64.41, 70.79 and 54.02%), respectively, when compared to the control diet. There was no difference between diets in relation to urinary volume, however the excretions of creatinine were influenced. The NB did not change with the inclusion of lipids, however, purine derivatives excretions (PD mmol/dia), purine derivatives absorption (PD abs. mmol/day), microbial nitrogen production (N microb mmol/day), microbial crude protein (CP microbial g/day) and microbial protein efficiency synthesis (ESPBmic (g)/kgNDT) were influenced by addition of dietary lipids, so that the lowest means for these variables were for diet supplemented with CaAgCl (3.48, 2.95, 2.14, 13.40, 21.31 mmol/day), respectively. The ruminating time (RT), number of chews (No/day), chews per bolus (No/bolus) are influenced in accordance with the addition of lipids in the diet, so that longer times have been expended for the CAL treatment (10,14, 78,91 and 61,026), respectively. The animals fed heavily at times on the periods of 06 to 12 and 12 to 18 h and ruminated in periods that comprised the intervals 18 to 24 and 24 to 06 h. Supplementation with different lipid sources did not influence the consumption of DM and nutrients, with the exception of EE and NFC intake but influences the digestibility of DM and nutrients. NB and urine volume are not affected according to the lipid inclusion in diets, however, the excretions of creatinine are influenced and microbial production is reduced when CaAgcl are part of the diet. The lipid supplementation influences diary cycle patterns on intake behavior in Santa Ines sheep.