Effect of the use of different roughages on the consumption and behavior of newly weaned foals

The objective was to evaluate the consumption and behavior of recently weaned foals receiving different sources of roughage. Twenty recently weaned foals of the Mangalarga Marchador breed, with an average of 6 months and 135.9kg, were distributed into four groups: corn silage (CS), conventional hay (HAY), pelleted hay (PELET), and haylage (HL). The diets were formulated to meet the requirements of the category and were isoproteic and isoenergetic. The experimental period lasted 110 days, with the first 35 days of adaptation. The dry matter intake was manually measured at the beginning, middle, and end of the twenty foals experiment, and the ingestion and ingestive behavior of ten foals were also evaluated in an automated way (Intergado®). Two behavioral assessments were also performed (START and END) through visual observations at 5-minute intervals for 24 hours. Ingestion and behavior results were analyzed in a randomized block design (RBD) with split plots, and the results recorded by the Intergado® electronic feeder were analyzed in RBD, and the means were compared by Tukey test at 5% of significance. The lowest forage dry matter (FDMI) and total (TDMI) intakes throughout the experiment were from the CS treatment and the highest was from the HAY Similar results were found for FDMI measured by the Intergado® feeder (FDMIi). At the START, the CS and PELET treatments provided the lowest times consuming roughage and the longest times standing idle and performing stereotypical behavior. At the END, the same treatments provided the shortest times in social interaction and the longest times performing stereotypic behavior. PELET continued to be the treatment with the shortest time-consuming roughage. Thus, CS should not be used as a roughage base in diets for recently weaned foals, as it results in lower FDMI and lower TDMI, resulting in longer idle times and higher frequency of stereotypic behavior. The pelleted hay should be used with caution, because in addition to causing less consumption time, longer idle time, and greater frequency of stereotypic behavior, it can cause colic.