Effects of short-term feed restriction on the physiological parameters and metabolites of F1 Holstein x Zebu cows in different stages of lactation / [Efeitos da restrição alimentar de curto prazo sobre os parâmetros fisiológicos e metabólicos de vacas F1 Holstein x Zebu em diferentes estágios da lactação]

This study aimed to evaluate the effects of different nutritional plans on the productive, physiological and metabolic parameters of F1 ½ Holstein x ½ Zebu cows in different stages of lactation. Sixty lactating cows were allotted to a completely randomized 5 x 3 factorial design with five feed allowances and three lactation periods. The dry matter intake, milk yield and heart rate were reduced by 5.69kg, 2.41kg and 10.36 beats/min (morning) and 10.25 beats/min (afternoon) for each 1% feed restriction, respectively. There was no difference in the concentration of glucose, total protein, albumin, cholesterol and non-esterified fatty acids for cows subjected to different feed allowances, with means of 95.25, 7.98, 2.95, 121.68 and 0.45mg/dL, respectively. Feed restriction of up to 2.50% BW is a cost reduction strategy that does not alter milk yield, regardless of the stage of lactation.(AU)

Objetivou-se avaliar os efeitos de diferentes planos nutricionais sobre as características produtivas, fisiológicas e metabólicas de vacas F1 ½ Holandês x ½ Zebu. Foram utilizadas 60 vacas em lactação, seguindo-se o delineamento inteiramente ao acaso, em esquema fatorial 5 x 3, com cinco níveis de oferta de dieta e três períodos de lactação. À medida que se aumentou 1% na restrição da oferta da dieta, houve redução linear de 5,69kg no consumo de matéria seca pelos animais, 2,41kg na produção de leite, bem como de 10,36bat/min (manhã) e 10,25 bat/min (tarde) na frequência cardíaca dos animais. Não houve diferença para a concentração de glicose, proteínas totais, albumina, colesterol e NEFA com a restrição na oferta da dieta dos animais, sendo a média de 95,25, 7,98, 2,95, 121,68 e 0,45mg/dL, respectivamente. Recomenda-se a restrição de até 2,50% de peso corporal como estratégia de redução dos custos em todos os estágios em lactação, visando não alterar, economicamente, a produção de leite.(AU)

Efeito do transporte de péletes sobre sua qualidade / Effect of pellets transport on its quality

The objective of this study was to evaluate the quality of pellets from the end of the pelletizer machine until the end of the line feed plate, using two methods of analysis: pellet durability index (PDI) and EMBRAPA pelletizing method (MEP). Furthermore, the effect of the discharging methods at the broiler farm on the physical quality of pellets using MEP as a method of analysis was evaluated. The first phase of the experiment was a randomized block with six treatments: A - pellets at the end of the pelletizer machine; B - pellets inside the truck; C - truck's discharging at the feed silo; D - place inside the warehouse after the feed silo; E - the middle of the feed plate line and F - the end of the feed plate line. The experiment was carried out in seven replicates (blocks). The second phase of the experiment was a randomized block with two treatments: A - smaller discharge opening (for pellets feed); B - bigger discharge opening (for mashed feed). The experiment was performed with twelve replicates (blocks). The discharge of the pellets feed at broilers farm is the point that worsens the pellets quality. The discharge of pellets feed by the truck should be done with the bigger discharge opening. Moreover, MEP showed to be a better method than PDI to evaluate the integrity of the pellets for broiler chickens.(AU)

Potencial antiviral da quercetina sobre o parvovírus canino / Antiviral potencial of quercetin in canine parvovirus

Avaliou-se o efeito do flavonoide quercetina na replicação do parvovírus canino in vitro por meio do ensaio de determinação da atividade virucida (ensaio 1), ensaio de determinação da atividade sobre a célula (ensaio 2) e ensaio de tempo de adição das drogas em diferentes etapas do ciclo replicativo viral (ensaio 3). A quercetina apresentou significante atividade antiviral, com valores máximos de redução do título viral de 96,3% no ensaio 1, 90% no ensaio 2 e 90% no ensaio 3. Os efeitos mais expressivos ocorreram nas etapas de adsorção e penetração viral. Os resultados deste trabalho sugerem a importância da quercetina para a medicina veterinária.

The in vitro effect of the flavonoid quercetin against canine parvovirus was evaluated. The antiviral activity of quercetin was evaluated by determining the virucidal activity (assay 1), determining the activity on the cell (assay 2) and using the time of addition assay to test the inhibition of the viral replication cycle (assay 3). Quercetin showed a significant antiviral activity, with maximum viral titer reduction of 96.3% in assay 1, 90% in assay 2 and 90% in assay 3. The most expressive effects occurred in the stages of viral adsorption and penetration. The results show the importance of quercetin for veterinary medicine.