Comportamento durante o desmame de peixe-boi-da-amazônia Trichechus inunguis (NATTERER, 1883) em cativeiro.

Abstract

The amazonian manatee Trichechus inunguis (Natterer, 1883) has been widely exploited by hunting, being one of the most hunted sea mammals in the twentieth century. Currently its hunting is prohibited. However, the legal provisions do not prevent young specimens, for various reasons, beached and require care in captivity for rehabilitation of this species. The Chico Mendes Institute of Biodiversity Conservation (ICMBio) maintained a base of the Center for Conservation and Management of Aquatic Mammals Research (CMA) installed at the Federal Rural University of the Amazon (UFRA) with enclosures for rehabilitation of Trichechus inunguis. Some of them come young animals, still lactating, so as they grow, are stimulated to weaning, that in captivity of this study, occurred in thirty days. The behavior of the animals and the water quality of the enclosures in seven specimens of this species has been the object of this study, comparing the execution patterns of some behaviors during lactating, weaning and after weaning, during herbivory. In addition, four limnological parameters of water of three enclosures were analyzed considering the different nutritional support provided by weaning. The results indicate, among other behaviors, significant differences in the frequencies of execution related to feeding behavior by statistical KruskalWallis test (p value <0.0001) having behavioral response of animals to decrease the supply of nutrients provided by feedings. With the same statistical test, one of the behaviors that is classified as a stereotype of captivity (movement in circles) was decreasing as the animal leaves the lactating to herbivory (p value <0.0023). Limnological parameters related to phosphate compounds (total phosphorus and phosphate) also showed significant difference when values were adjusted due to the biomass and volume of enclosures, according to the number of bottles that were offered daily, being subjected to analysis of variance ANOVA (p value <0.0002, p value <0.0032) showing equal when animals suckle one or no bottle for both phosphate compounds. The ammoniacal nitrogen parameter, when adjusted and subjected to analysis of variance ANOVA showed no statistical difference when bottles were being removed. There was variation in temperature between the enclosures (ANOVA: P value <0.039). The offer of three plant species Pistia stratiotes L., Eichhornia crassipes (Mart.) Solms and Hymenachne amplexicaulis (Rudge) Nees, in order to perform weaning and maintain the captive animals in full herbivory shown nutritionally inadequate, since the subsequent problems related to feeding.