Raylon Pereira Maciel

Consumo, digestibilidade e desempenho de novilhas leiteiras alimentadas com dietas contendo torta de dendê

The objective was to evaluate the effects of inclusion of palm kernel cake in the diet on intake, digestibility and performance of dairy heifers. Sixteen dairy Holstein-Zebu crossbred heifers with average age of 13 months and average weight of 183.4±32.5 kg were distributed to four treatments in a completely randomized design with four levels of palm kernel cake (0, 11.9, 22.9 and 34.2% from total dry matter), each one with four replicates. The intake of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), non-fibrous carbohydrates (NFC), ether extract (EE) and total digestible nutrients (TDN), and the apparent digestibility of DM, CP, NDF, NFC and EE were evaluated. There was linear reduction in DM, CP, NDF, NFC, and TDN intake. The apparent digestibility of DM and NDF reduced with the inclusion of palm kernel cake in the diet, while the apparent digestibility of CP and NFC showed quadratic effect. The inclusion of palm kernel cake in the diets resulted in linear increase in the apparent digestibility of ether extract. Weight gain decreased linearly with the inclusion of palm kernel cake in the diet, with values of 1.06, 0.99, 0.89 and 0.54 kg/day for diets containing 0, 11.9, 22, 9 or 34.2% palm kernel cake, respectively. Feed conversion was not affected by the inclusion of levels of palm kernel cake. The inclusion of palm kernel cake in the diet reduces nutrient intake and performance of dairy heifers during growth, but when used in levels up to 24.6% of the total diet, it provides weight gain compatible with growth programs aiming calving at 24 months of age.

Consumo e digestibilidade de dietas contendo níveis de farelo do mesocarpo de babaçu para ovinos

The objective of this study was to evaluate the intake, apparent digestibility of nutrients and the nitrogen balance of diets containing babassu-mesocarp meal (BMM) as a replacement for elephant-grass silage (0, 21, 38, 62 and 78%). Twenty sheep were used, housed in individual metabolic cages and distributed in a completely randomized design with four replications. Food intake was noted and faeces and urine excretions were collected and recorded. Intake of dry matter, organic matter, crude protein, ash, neutral-detergent fibre, acid-detergent fibre, hemicellulose, and total carbohydrate was not affected by the experimental diets. Changes were observed in the non-fibrous carbohydrates intake (INFC) and a reduction in the intake of ether extract as a % of live weight (LW) and grams per unit of metabolic body size (g MBS-1). Total digestible nutrient intake (ITDN) presented quadratic behaviour, with maximum points at 37.3% and 37.9% of BMM expressed as %LW and g MBS-1 respectively. The apparent digestibility of organic matter, neutral-detergent fibre, acid-detergent fibre, crude protein and non-fibrous carbohydrate decreased with the increase in BBM in the diet. The apparent digestibility of dry matter (ADDM), ether extract and non-fibrous carbohydrates showed a quadratic response, with maximum ADDM estimated at 10% of BMM. The TDN decreased by 0.28% for each percentage point of BMM added to the diet. The addition of BMM reduced digestibility of the fibres and increased both INFC and ITDN, indicating that this byproduct can be used as an energy source in ruminant diets.

Production responses in young bulls fed glycerin as a replacement for concentrates in feedlot diets

We assessed the productive performance, blood parameters, and carcass characteristics of young crossbreed dairy bulls kept in feedlots and fed with diets containing 0, 60, 120, and 240 g/kg of crude glycerin, replacing a mixture of ground pearl millet grain (50%) and babassu mesocarp bran (50%). Twenty-four bulls with an average age of 24 months and an average initial weight of 390 ± 31.5 kg were used. The experimental design was completely randomised with six replications. Dry matter and digestible energy intake were not influenced by diets. Feed conversion linearly decreased with increasing glycerin levels. The increase in the levels of glycerin resulted in a linear increase in blood glucose and in average daily weight gain. Carcass weight was not affected, but trimming fat increased and carcass yield decreased linearly, with increasing glycerin levels. The addition of crude glycerin at levels up to 240 g/kg of dry matter to diets containing babassu mesocarp bran and ground pearl millet grain increased the performance of young feedlot bulls, and improved feed efficiency and carcass subcutaneous fat thickness.

Performance, rumen development, and carcass traits of male calves fed starter concentrate with crude glycerin

The objective of this study was to assess the effects of including crude glycerin in the diet on intake, performance, rumen development, and carcass traits of dairy crossbred veal calves fed starter concentrate containing 0, 80, 160, and 240 g kg−1 crude glycerin. Twenty-eight calves with an average weight of 38.03±6.7 kg and five days of age were distributed in a completely randomized design with four treatments with seven replications. Calves were individually housed in covered stalls equipped with feeders and drinkers for 56 days. The calf response to inclusion of crude glycerin in the concentrate changed over the weeks and the inclusion level of 240 g kg−1 resulted in greater dry matter intake and average daily gain. There was no effect on the final weight and total weight gain of the animals, with mean values of 73.60 and 35.16 kg, respectively. The weight of the rumen-reticulum adjusted for body weight, empty body weight, and total stomach weight increased linearly with the inclusion of crude glycerin. Blood total protein, globulin, urea, cholesterol, gamma glutamyl transferase, aspartate aminotransferase, and alkaline phosphatase concentrations did not differ among treatments. Carcass traits and meat color were not affected. Crude glycerin can be added to dairy calf starter concentrate up to 240 g kg−1 dry matter because it benefits concentrate intake, performance, and rumen development without affecting animal health.