Utilização de lactobacillus paracasei como probiotico para o controle de Salmonella spp em frangos de corte

Abstract

The objective of the commercial poultry keeping is getting high productivity for a low cost and offering to the consumer a product with quality. A pathogenic bacterium that has been worring the avicola section during the last years is the Salmonella. To control this bacterium, it was proposed in this paper the Lactobacillus paracasei, used as probiotic. The Lactobacillus paracasei can be in the future a healthy alternative for the indiscriminate antibiotics use, forbidden for export. This assignment was carried out in the Biotery of Veterinary Preventive Medicine of the Federal University of Santa Maria RS (Biotitic of Medicinal Preventive Veterinaries of Public University of Santa Maria RS). Cutting commercial chicks with a day of living were used. They were remained in wire cages, with a heating system. The feeding was ration (not medicated) and water. The treatments were done in the first day of living of the chicks. It was administrated a probiotic sprayed in the water, and salmonella for endo-esofagic inoculation. The pulverization was done with a manual spray. The endo-esofagic inoculation was done with a probe and syringe with 1ml, with 0,1ml of Salmonella Enteritidis for each chick. For the pulverization and for the water, the inoculo had 1010 UFC/ml of Lactobacillus paracasei and for the endo-esofagic tract 103 UFC/ml of Salmonella Enteritidis. Three groups of twenty chicks were used, distributed as follows: Portion 1- Control; Portion 2- pulverization and addiction of probiotic in the drinking water; Portion 3 addition of probiotic in the drinking water and inoculation of Salmonella Enteritidis; In each week, three chicks from each portion were withdrawn from each group to be weighed, sacrificed and for material collection. The presence in the excrements and the colonization of the cecos of cutting chicks for Salmonella Enteritidis was reduced significantly in the groups treated with Lactobacillus paracasei (P2) for pulverization and addiction in the drinking water. Therefore, we can conclude that the use of probiotics inhibits or reduce the salmonella development, in the intestinal treat of the birds, since we can constact its presence in the Treatment Control (P1) in three samples probably because of the presence of bacterium in the feed, water or environment where the birds were. In the treatment with Addiction of Lactobacillus paracasei in the drinking water + inoculation of Salmonella Enteritidis, we verified three absences of salmonella, in the 0; 32; and 42 days of treatment. In the positive samples for salmonella, we observed characteristic damages in the liver, typical of the contamination with salmonella, which affects the bloodstream, probably in an intracellular way, and are removed by the river, spleen or bone marrow. During the 32 and 42 days, there were absences of SE, which indicate the inhibitory capacity of the probiotic used. We observed that the inhibition occurs later. The gain of weight of the portion that received sprayed Lactobacilllus paracasei in the drinking water (P2) did not de different of the other treatments. As this same treatment did not accused the presence of SE in the excrements, while the other groups treated with probiotic the rates of SE in the excrements were detected, there is the indication that the presence of Salmonella Enteritidis does not interfere decisively in the cutting chickens productivity. Although it has not occurred significant variation among the groups, related to the body weight, the group treated with Lactobacilllus paracasei sprayed in the drinking water (P2), presented the best performance.