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This study evaluated the effects of replacing ground corn with buriti oil ( L.) on feed intake and digestibility and on the production, composition, fatty acid profile and sensory characteristics of goat milk. A double Latin square (4 × 4) was used; eight goats were distributed in a completely randomized design. The square comprised four periods and four buriti oil concentration (0.00; 1.50; 3.00 and 4.50% of total DM) replacing corn. Intakes of DM, CP, NDF, ADF, non-fibrous carboydrates (NFC) and TDN were not affected by the replacement of corn with oil in the diet. However, lipids intake was increased ( < 0.01) by 100% in the diet of goats with 4.50% oil inclusion, as total DM. DM and CP digestibility were similar between the buriti oil concentrations. However, lipid digestibility increased linearly ( = 0.01) and may have contributed to a quadratic reduction in NDF digestibility ( = 0.01) and a linear reduction of NFC ( = 0.04) with buriti oil content in the goat feed. Goat milk production, corrected production and chemical composition were not influenced by the concentration of buriti oil replacement; however, milk fat concentration ( = 0.04) and feed efficiency ( < 0.01) increased linearly with the amount of buriti oil in the diet. There was a linear reduction on hypercholesterolemic SFA such as C12:0 ( < 0.01) and C14:0 ( < 0.01) as well as the atherogenic index (AI; < 0.01) with buriti oil inclusion in goat's diet. In contrast, the fatty acids C18:0 ( < 0.01) and C18:1 9 ( < 0.01) increased linearly in the milk of goats that were fed with buriti oil. However, CLA ( < 0.01) varied quadratically; the maximum production of 0.62 g/100 g of fat was observed when using 1.50% buriti oil. The sensory characteristics of the milk were not changed ( > 0.05) by the replacement of corn with buriti oil in the goats' diet. It is recommended to replace corn with buriti oil in goat feed by up to 4.5% of total DM, resulting in improved feed efficiency and milk fat without affecting production; this recommendation satisfies the minimum requirements of the industry and preserves the organoleptic characteristics of the milk and its acceptability for human consumption. In addition, buriti oil replacing ground corn by up to 4.5% DM in the diet of lactating goats decrease medium-chain SFA which are hypercholesterolemic and increase the concentrations of the C18:19, CLA and DFA in goat milk fat, helping to protect against cardiovascular disease.

The aim of this study was to estimate the energy and protein requirements for maintenance and growth of lambs. A total of 35 crossbreed Dorper × Santa Ines lambs [31 ± 1.28 kg of initial body weight (BW) and 4 months old] were distributed in a completely randomized design with three treatments groups (ad libitum, 30 and 60% of feed restriction). Five lambs were slaughtered at the beginning of the experimental trial as a reference group to estimate the initial empty BW (EBW) and body composition. When the animals of the ad libitum treatment reached a BW average of 47.2 kg, at day 84 of trial, all lambs were slaughtered. The feed restriction promoted reduction in body fat (P &lt; 0.001) and energy concentration (P &lt; 0.001), while protein showed a quadratic response (P = 0.05). The equations obtained for NEg and NPg requirements were 0.2984 × EBW0.75 × EBWG0.8069 and 248.617 × EBW−0.15546, respectively. The net energy (NEm) and protein (NPm) for maintenance were 71.00 kcal/kg EBW0.75/day and 1.76 g/kg EBW0.75/day, respectively. In conclusion, the NEg and NPg requirement for lambs with 30 kg of BW and 200 g of average daily gain (ADG) were 0.736 Mcal/day and 24.38 g/day, respectively. Our findings indicate that the NEm for crossbreed Dorper × Santa Ines lambs is similar to those recommended by the international committees; however, we support the hypothesis that the requirements for gain are lower.

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