Effect of Feeding Frequency of Fresh Forage on Ruminal pH: Data Review

Data of 58 × 24 observations of hourly ruminal pH dynamics, used in 13 experimental treatments of 6 independent trials, were used for the study. Each 24-hour observation was categorized according to the feeding frequency of the animals (lambs, ewes, heifers or cows) in ‘continuous access to food’ (C) when they were fed in 4 meals or more (26 ×24 observations) or in ‘restricted access to food’ (R) when they were fed in 1 or 2 meals per day (32×24 observations). All the experiments were performed in the Nutrition and Physiology Departments (Facultad de Veterinaria, UdelaR). Diets were composed by fresh temperate pastures (grasses and legumes) as main component, and some of them included concentrates at a maximum rate of 30% of the diet. For the analysis, pH data for 24 h and from 0 to 8 hours relative to the beginning of the main meal (0-8 h) were considered separately. pH values were analyzed as repeated measures using the mixed model including observation, experiment, treatment (C or R), hour and treatment×hour interaction effects. Mean ruminal pH for 24 h was lower for ...