Alyson Andrade Pinheiro

Fatty Acid Profile of Milk and Cheese from Dairy Cows Supplemented a Diet with Palm Kernel Cake.

Lipid supplements (oilseeds vegetables) are included in ruminant diet to increase its energy density and improve fatty acid composition of milk and consequently of fresh cheese. Milk and cheeses were evaluated from crossbred Holstein × Zebu, fed diets enriched with 0%, 25%, 50%, and 75% inclusion levels of palm kernel cake in concentrated supplement, which were supplied daily (3.0 kg). Milk and fresh cheese (p = 0.001) fatty acids C12:0 exhibited quadratic negative values. Milk fatty acids C13:0, C20:0, C18:2t10c12, and C20:2n-6 presented positive quadratic values. The milk C18:2n-6 decreased linearly and in fresh cheese exhibited an increasing linear effect (p = 0.016). However, the fatty acids grouped in milk fat were not affected. The medium-chain fatty acids varied negatively and quadratically (p = 0.045). There was no effect on milk and fresh cheese chemical composition (p > 0.05). The milk fat was increased (p = 0.0065) quadratically (minimum point of 24.7%). Thus, the addition of palm kernel cake to cow diets negatively altered the fatty acid profile, it raises the percentage of lauric (C12) and tridecanoic (C13) acids fat which is not beneficial to human health from a nutraceutical perspective, although it did not influence the atherogenicity index.

Consumo e digestibilidade aparente em novilhas alimentadas com dietas contendo cana-de-açúcar tratada com óxido de cálcio

This study was developed to evaluate the intake and apparent digestibility of nutrients in dairy heifers fed diets containing sugar cane treated with calcium oxide (CaO). It was also evaluated the prediction efficiency of dry matter intake and food energy value. Twenty Holstein-zebu crossbred dairy heifers, at 200 kg average initial body weight were used, distributed in a completely randomized design, with four diets and five repetitions. The diets were formulated to be isoprotein and to supply 14% crude protein and they were composed of 71% sugar cane treated with 0; 0.75; 1.5 or 2.25% calcium oxide (in natural matter basis) corrected with 1% of urea and ammonium sulfate (9:1) and 29% of concentrate. Intakes of dry matter (DM), organic matter (OM), ether extract (EE), neutral detergent fiber (NDF), neutral detergent fiber corrected for ash and protein (NDFap), indigestible neutral detergent fiber (iNDF), total carbohydrates (TC), non-fibrous carbohydrates corrected for ash and protein (NFCap) and total digestible nutrients (TDN) (% BW) were linearly reduced with calcium oxide doses. Digestibilities of OM, NDF, NDFap, total carbohidrates and NFCap and TDN content in the diets were not affected. However, hydrolyses of sugar cane with calcium oxide caused reduction in the digestibility of DM and CP. The equations proposed by National Research Council underestimated intakes of DM and TDN and digestible CP and NFC and overestimated intakes of digestible NDF. Hydrolyses of sugar cane with calcium oxide do not improve intake of nutrients neither digestibility of nutrients in dairy heifers. The equations proposed by National Research Council are not efficient to estimate the DM intake and food energy value in experimental conditions.

Avaliação de Equações para Predição do Valor Energético de Dietas com Torta de Amendoim (Arachis hypogaea)

Objetivou-se avaliar as equacoes adotadas pelo NRC e Detmann para estimar o conteudo energetico via nutrientes digestiveis totais (NDT), de dietas contendo torta de amendoim. O valor energetico das dietas foi estimada a partir das equacoes do NRC e de Detmann e feita a avaliacao das mesmas equacoes para predicao do valor energetico, confrontadas com os dados obtidos atraves de experimento de digestibilidade in situ. Foram utilizados cinco bovinos mesticos Holandes x Zebu, castrados, dispostos em um quadrado latino 5 x 5. As dietas foram compostas de feno de tifton, milho moido, farelo de soja e torta de amendoim. Os tratamentos foram constituidos de zero (100% de farelo de soja), 25, 50, 75 e 100% de substituicao por torta de amendoim no concentrado. O coeficiente de inclinacao da reta nao diferiu estatisticamente de um para as variaveis analisadas. As equacoes propostas pelo NRC e Detmann foram eficazes para estimar o valor energetico de dietas com torta de amendoim no concentrado. DOI:10.15528/2176-4158/rcpa.v14n2p199-202

Avaliação Econômica de Diferentes Níveis de Suplementação na Terminação de Novilhos Nelore em Pastagens de Brachiaria brizantha

Neste estudo, objetivou-se avaliar as respostas economicas de quatro niveis de suplementacao na terminacao de novilhos Nelore em pastagens de Brachiaria brizantha no Sudoeste da Bahia. O experimento foi desenvolvido na Fazenda Boa Vista, localizada no municipio de Macarani – Estado da Bahia, entre os meses de agosto de 2006 e fevereiro de 2007. A parte de campo foi implantada numa area de 52,0 ha, dividida em oito piquetes de aproximadamente 6,5 ha cada, subdivididas em formato de pizza com aguada central. Testaram-se quatro niveis de suplementacao em funcao do peso vivo: sal mineral, 0,3%, 0,6% e 0,9% do peso vivo do animal. Os niveis de suplementacao criaram uma diferenciacao na epoca de comercializacao dos animais o que representam, na pratica, diferentes precos em funcao do mes de venda dos lotes de animais. A curva de crescimento da receita e menos acentuada do que a curva de crescimento dos custos, direcionando para um achatamento do lucro em funcao dos niveis de suplementacao estudados. Niveis de suplementacao na terminacao, inferiores a 0,3% do peso vivo, apresentam potencial economico. DOI:10.15528/2176-4158/rcpa.v12n1p110-113