NUTRIÇÃO DE PRECISÃO PARA VACAS LEITEIRAS

Within a dairy farm there are differences between the diets formulated, offered and actually consumed by the animals, in a way that they can interfere with the productive performance, because of errors that are multifactorial. Assessing the ingestive behavior of lactating cows is a tool that makes it possible to understand the challenge that the animal is facing, both in terms of diet and factors related to the environment. Accelerometer sensors allow continuous monitoring of these variables, helping the producer to understand the behavior of his flock. As foods within a property may have nutritional values different from those listed, the use of NIRS (Near Infrared Spectroscopy - Near Infrared Spectroscopy) allows chemical-bromatological analyzes to be carried out in a practical, fast and cheap way, generating data immediately delivery and enabling the formulation of new diets in a shorter time. The particle length of forages offered to the animals must be in a standard that allows the correct consumption of dry matter and productive performance, as well as ensuring adequate rumen health and activity. Thus, the Penn State Particle Separator was developed with the aim of evaluating the percentages of different particle sizes that make up the diet, as well as the animal selection pattern and possible errors in the mixing time of the ingredients in the forage carDentro de uma propriedade leiteira existem diferenças entre as dietas formuladas, ofertadas e realmente consumida pelos animais, de maneira que podem interferir no desempenho produtivo, por causa de erros que são multifatoriais. Avaliar o comportamento ingestivo de vacas em lactação é uma ferramenta que possibilita entender qual o desafio que o animal está enfrentando, tanto em nível dietético, como por fatores relacionados ao ambiente. Os sensores acelerômetros permitem o monitoramento continuo dessas variáveis, auxiliando o produtor a entender o comportamento de seu plantel. Como os alimentos dentro de uma propriedade podem possuir valores nutritivos diferentes daqueles tabelados, o uso do NIRS (Near Infrared Spectroscopy - Espectroscopia no infravermelho próximo) permite que sejam realizadas análises químico-bromatológicas de uma forma prática, rápida e barata, gerando dados a pronta entrega e possibilitando a formulação de novas dietas em um tempo menor. O comprimento de partículas dos volumosos ofertados aos animais devem estar em um padrão que possibilitem o correto consumo de matéria seca e desempenho produtivo, bem como garantam a saúde e atividade ruminal adequadas. Dessa maneira o Separador de Partículas Penn State (Penn State Particle Separator), foi desenvolvido com o intuito de avaliar as porcentagens de diferentes tamanhos de partículas que constituem a dieta, bem como o padrão de seleção dos animais e possíveis erros no tempo de mistura dos ingredientes no vagão forrageir

Intensity and interval of recovery in strength exercise influences performance: salivary lactate and alpha amylase as biochemical markers: a pilot study

Purpose The aim of the present study was to evaluate the effects of intensity and interval of recovery on performance in the bench press exercise, and the response of salivary lactate and alpha amylase levels. Methods Ten sportsman (aged 29 ± 4 years; body mass index 26 ± 2 kg/cm2 ) were divided in two groups: G70 (performing a bench press exercise at 70 % one repetition maximum—1RM), and G90 (performing a bench press exercise at 90 %—1RM). All groups were engaged in three intervals of recovery (30, 60 and 90 s). The maximum number of repetitions (MNR) and total weight lifted were computed, and saliva samples were collected 15 min before and after different intervals of recovery. For the comparison of the performance and biochemistry parameters, ANOVA tests for repeated measurements were conducted, with a significance level set at 5 %. Results In G70, the 30 s MNR was lower than the 60 and 90 s intervals of recovery (p\0.05) and the MNR with the 60 s interval of recovery was lower than the 90 s interval of recovery (p\0.041). Similarly, in G90 with the 30 s of interval of recovery, the sets were lower than observed with the 60 and 90 s (p\0.05), and MNR with the 60 s interval of recovery was lower than the 90 s interval of recovery (p\0.05). The salivary lactate showed an increase after exercise (p\0.05) when compared with the rest period for all groups, and no effects were observed for salivary alpha amylase. Conclusions Based on this result, the sets and reps can be modified to change the recovery time. This effect is very useful to improve the performance in relationship to different fitness levels