Comportamento e ganho de peso de leitões na fase de creche com diferentes estratégias de enriquecimento ambiental

Abstract

Environmental enrichment is a strategy that consists in the installation of toys in the environment where production animals are confined, with the objective of increasing positive interactions of the animals and consequently reducing atypical behaviors and improving their performance. Thus, the objective of this study was to evaluate, during 10 days, the behavior and weight gain of pigs in the nursery phase based on the influence of three different types of environmental enrichment that were installed in the pens. The experiment was carried out in an entirely randomized design, with four treatments, with the pens as an experimental unit. There were four replicates for each treatment, being: Treatment 1 - control; Treatment 2 - enrichment with tires; Treatment 3 - enrichment with suspended bottles, and Treatment 4 - enrichment with balls of pet bottles loose on the floor, totaling 16 pens. To characterize the behavior, an ethogram was used and the behaviors expressed by the piglets were observed from 13:00 to 17:00, with 30-minute intervals, for each day of evaluation. The behaviors were evaluated: Playing with Objects (BO), Playing Without Objects (BSO), Agonistic Behaviors (AC), Lying or Sleeping (D), Sniffing the Stall (FB), Sniffing the Other (FO), Ingesting Water (AG), Ingesting Food (AL), Locomotion (L) and, Other (O). To evaluate weight gain, an average weighing of each of the 16 pens was done on the first and last day of the experiment in order to identify whether or not there were differences in weight gain between treatments. In the stalls where the tires were installed, it was noted that the animals expressed with less intensity the agonistic behaviors and even greater interaction with the toys. The same happened with treatments 3 and 4 in relation to the control group, suggesting that any of the three types of enrichment would be sufficient for the piglets to interact in a positive manner. Observing the results of weight gain it was noted that treatment 2 (enrichment with tires) showed a higher final weight in relation to the other three treatments. On the other hand, in treatments 3 and 4, the final weight was higher than in treatment 1, but lower than in treatment 2. Therefore, the use of hanging tires proved to be an efficient and low cost strategy to reduce the occurrence of disputes and fights in nursery stalls, and may also improve the weight gain of animals in this phase.