Airon Aparecido Silva de Melo

Avaliação de diferentes suplementos para vacas mestiças em lactação alimentadas com cana-de-açúcar: desempenho e digestibilidade

The objective of this study was evaluate the intake, milk production and composition, nutrients digestibility and feed efficiency of crossbred cows of low potential of production fed diets based on sugar cane. It was used eight cows crossbred Holstein/Gir, with medium live weight of 425 kg, after the initial third of lactation. They were distributed in two Latin squares (4x4), in agreement with the lactation order, feeding with complete diets to the sugarcane base, being, cane more urea (CAU); cane, urea and cottonseed meal (CFA); cane, urea and corn (CMM); cane, urea and wheat meal (CFT). The intakes of DM, ADF, NDF and OM were higher for CFA and CFT in relation to the others. The intake CP was higher to CFA in relation to CAU. However, the intakes of THC, FNC and TDN presented the same behavior, being higher for CFT and CFA in relation to CAU. The digestibility for DM and OM were higher to CMM in relation the others; however the digestibility of the CP was higher to CFA, in relation to the others. Those digestibilities of the NDF, THC were higher to CMM in relation to CFA. However the digestibility of the ADF was lower to CFA in relationship the others. The levels of TDN were higher to CMM and CAU in relation the others, ranged from 88.25 to 74.44%. The milk production corrected for 4.0% of fat was lower to CAU in relation to the others treatments. There was no alteration in the protein and milk fat levels. However, for protein and fat productions the milk, the treatment CAU was lower to the others. CFA presented to lower feed efficiency.

Microbial protein synthesis and urea nitrogen concentrations in lactating dairy cows fed spineless cactus and different forages based diets.

Five Holstein cows were allotted to a 5 × 5 Latin square design with the objective of evaluating the microbial protein production, using the total excretion of purine derivatives (PD), obtained from spot urine collection, plasma and milk urea and nitrogen (N)-urea. The five treatments contained different forage sources: sugar cane bagasse (CB), tifton hay (TH), elephant grass hay (EH), sorghum silage (SS) and a mixture of sugar cane bagasse + sorghum silage (CBSS). The milk urea (10.98 mg/dL) and N-urea (5.11 mg/dL) concentrations were not influenced by the forage sources, such as plasma urea (28.10 mg/dL) and N-urea (13.09 mg/dL) concentrations. The urinary urea, N-urea, allantoin and PD excretions, the absorbed purine, N-microbial synthesis and milk allantoin concentration remained unchanged. The different forage sources in association with forage cactus did not change the microbial protein production.

INDICADORES REFERÊNCIA (BENCHMARKS) DE SISTEMAS DE PRODUÇÃO DE LEITE DE VACAS NO AGRESTE PERNAMBUCANO

The objective of this work was to identify and assess the technological, zootechnical and socioeconomic profiles and identify and quantify benchmarks for dairy cattle production systems, in a nonexperimental approach, aiming to contribute to the sustainability and competitiveness of dairy farming in the Pernambuco Agreste region, northeastern Brazil. Thirty-six milk production systems of family and corporate farming were evaluated during twelve months, in order to identify and quantify the benchmarks. The systems were characterized regarding their size and technological, zootechnical and economic profiles. The correlation coefficients of the return rate on invested capital were assessed and regression equations were developed for each indicator, according to four scenarios of annual return rates (4, 6, 8 and 10%). The indicators evaluated were milk production per dairy cows, milk production per area, average price of milk, effective operational cost, total operating cost, total cost per price of milk and profitability. The dairy farming in the Pernambuco Agreste region pays the production costs, but tends to a not adequate remuneration of family labor and a need of external capital input for replacement of the assets. The productivity of production factors area and animals showed higher correlation with cost-effectiveness, denoting the need for increase the production through increases in land area and milk productivity per dairy cow. The identification and quantification of benchmarks may help to identify the weak points of dairy farming in the Agreste region, making it sustainable and competitive.

Caroço de algodão em dietas à base de palma forrageira para vacas leiteiras: síntese de proteína microbiana

Objetivou-se avaliar o efeito da inclusao de caroco de algodao em substituicao parcial a silagem de sorgo e ao farelo de soja em dietas a base de palma forrageira sobre a producao de proteina microbiana, a eficiencia de sintese de proteina microbiana e as concentracoes de ureia na urina e de ureia e N-ureia no plasma e no leite de vacas holandesas em lactacao. Foram utilizados cinco animais aos 50 dias de lactacao, distribuidos em quadrado latino 5 × 5. Os tratamentos consistiram de cinco niveis (0,0; 6,25; 12,50; 18,75 e 25,00%) de inclusao de caroco de algodao na MS da dieta. A inclusao de caroco de algodao na dieta nao influenciou a sintese de nitrogenio ou proteina microbiana, cujos valores medios foram 295,08 e 1.844,27 g/dia, respectivamente. As eficiencias de sintese de nitrogenio e proteina microbiana diminuiram linearmente, em proporcoes de 0,30 e 1,43 g para cada 1% de caroco de algodao na dieta, respectivamente. Os niveis de ureia na urina e de ureia e N-ureia no plasma e no leite nao foram afetados pela inclusao de caroco de algodao na dieta. Portanto, em dietas a base de palma forrageira, a inclusao de caroco de algodao em niveis de ate 25% da MS nao interfere na sintese de proteina microbiana e nas concentracoes de ureia.

Aceitabilidade por novilhas Girolando e valor nutricional da palma orelha-de-elefante-mexicana armazenada por diferentes períodos

The objective of this work was to evaluate the nutritional value of erect prickly pear (EPP) (Opuntia stricta), stored for different periods, and its acceptability by Girolando heifers. Five heifers were distributed in a 5x5 Latin square. The treatments were as follows: EPP without storage time; stored EPP for three post-harvest periods – 7, 14, and 21 days; and cochineal nopal cactus (CNC) (Nopalea cochenillifera) without storage time, as a control treatment. The diets offered to the animals were composed of cacti of the different treatments, as well as sugarcane silage and soybean meal, and were evaluated for their chemical composition, intake, and nutrient digestibility. The ingestive behavior of the heifers was evaluated. The cactus EPP did not differ from the CNC for organic matter, crude protein, neutral detergent fiber corrected for ash and protein, nonfibrous carbohydrates, total carbohydrates, ether extract, and mineral matter; however, EPP stored for different periods differed from CNC for dry matter and indigestible neutral detergent fiber. Heifer weights varied 1.35 kg with the low inclusion of concentrate in the diet. The cactus erect prickly pear maintains constant both its nutritional value and its acceptability to Girolando heifers, after storage for different periods up to 21 days.