ABSTRACT:The production capacity of green and dry mass of the entire plant, efficiency of N conversion, apparent N recovery and the chemical composition of cultivar Mulato II was evaluated under a system of cuts and nitrogen doses. The assay, conducted in the municipality of Goiânia, GO, Brazil, had a totally randomized 2 x 4 factorial design (2 height cuts, 0.40 and 0.50 m and 4 nitrogen doses), with three replications and subdivided subplots. Treatments comprised four N doses (0, 50, 100 and 150 kgha -1 N, with urea as nitrogen source). There was no significant interaction (p>0.05) between N doses and cut heights for the variables productivity of green (PGM) and dry (PDM) mass, nitrogen use efficiency (NUE) and apparent N recovery (ANR), which were neither affected (p<0.05) by N doses nor by evaluated cut heights. Average productivity reached 59,450 kgha -1 (PGV) and 10,367 kgha -1 (PDM) and it was produced an average of 19.62 kg of DM per kg of N, with a mean 56.00% recovery. N doses and cut heights did not affect (p>0.05) DM rates of the plant, whilst mean dry matter rate was 17.49%. CP rates were affected (p<0.05) by N doses (0, 50, 100 and 150 kgha -1 ) and cut heights (0.40 and 0.50 m) and by the interaction of these factors. CP rates of the entire plant hybrid Brachiaria cv. Mulato II increased (p<0.05) due to N doses through an increasing linear relationship. Since there was a significant effect (p<0.05) with regard to cut height and CP rates decreased with height increase. NDF rates were significantly influenced by N doses (p<0.05) and by cut heights (p<0.05), with significance for the interaction (p<0.05) of over 100 kgha -1 N doses only. No significant interaction (p>0.05) occurred in ADF rates among the variables analyzed. ADF contents were influenced by N supply (p<0.05) with decreasing quadratic regression as N doses increased.

The objective of this study was to characterize and identify the protein fractions of two cultivars of pearl millet (Pennisetum glaucum) – ADR-300 and cv. BN-1 – submitted to different nitrogen doses (0, 50, 100 and 150 kg.ha-1) at three cutting ages. The experimental design used was randomized blocks with a 4 x 3 factorial treatment structure, with three repetitions. The crude protein concentration (CP) and the protein fractions A, B1, B2, B3 and C of the pearl millet cultivars were evaluated by the Cornell Net Carbohydrate and Protein System. The CP concentrations differed according to the cultivars, with variation between the treatments of 14.01% to 23.29% for ADR-300 and 11.82% to 19.29% for BN-1. Fraction A (P<0.05) differed for the two cultivars, with variations also observed in the B1, B2 and B3 fractions in function of the treatments applied. Fraction C (P<0.05) differed among treatments only on the first cutting, for all doses for the two cultivars evaluated. The nitrogen doses and cutting age influenced the composition of the protein fractions.

The number of sheep flocks in Brazil is increasing. It is known that lambs must be slaughtered when young for producing quality meat. The current study evaluated the inclusion of protected methionine, protected lysine, lysophospholipid and amylolytic enzymes in a diet to lambs and their effects on weight gain and quantitative carcass traits at slaughtering. Eighty non-castrated male crossbred Dorper x Santa Inês lambs, 20.57 ± 4.33 kg live weight, were used. The feedlot lasted 64 days and 60 animals were slaughtered. There were no differences for live weight, daily feed intake, feed conversion and average daily weight gain at the first 28 days of feedlot. From the 28th day lysophospholipid treatment presented the highest live weight. Lysophospholipid and amylolytic enzyme presented the best performance in average daily gain, followed by protected methionine, control and protected lysine. Lysophospholipid treatment presented higher daily feed intake rates than protected lysine and protected methionine. Feed conversion was lower for amylolytic enzyme and higher for control. No changing in carcass traits was reported due to additives. Better performance may be achieved with feedlot lambs fed on diets with the addition of amylolytic enzyme and lysophospholipid at the finishing phase.

Resumo Foram avaliados a composição morfológica, os parâmetros agronômicos, a produção de massa seca das plantas forrageiras utilizadas para o processo de ensilagem, bem como a caracterização do processo fermentativo, em diferentes tempos de abertura dos mini-silos (3, 7, 15, 30, 60, 120 dias) após a ensilagem. Procedeu-se também às determinações das perdas de efluentes e gases, além da composição bromatológica e fracionamento de proteína das silagens. Também foi estimado o custo de produção e a produção de leite em função da matéria seca das silagens produzidas a partir de diferentes gramíneas. As espécies forrageiras avaliadas foram: milheto ADR-7010, sorgo BRS 610, milho AG 5055 com espiga, milho AG 5055 sem espiga e cana-de-açúcar IAC 86-2480. Foram observadas diferenças significativas tanto para produção, quanto composição bromatológica e custos de produção. O milheto não se mostrou competitivo com as demais forrageiras; entretanto, constitui opção como cultura de inverno em decorrência de sua baixa exigência hídrica quando comparado às demais culturas.

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