Vigilância da encefalopatia espongiforme bovina (EEB) no estado do Maranhão

Abstract

The present study aimed to characterize the surveillance of Bovine Spongiform Encephalopathy (BSE) in the State of Maranhão, to report a sanitary episode of ingestion of poultry litter by cattle and to describe the socioeconomic, productive and sanitary profile of poultry farms in the Maranhão hinterland, Brazil. To characterize the BSE surveillance, a survey was carried out of data extracted from the “Term of investigation of food supplied to ruminants in a breeding establishment” applied by the Official Veterinary Service, in the period from 2016 to 2019. The sanitary episode was the result of active surveillance by the official veterinary service in the municipality of São João dos Patos-MA, which, upon suspicion, collected a sample of the cattle feed for analysis. The profile of poultry farms in the Maranhão hinterland was obtained through interviews with the owners and on-site inspection of the establishments, where samples of poultry litter were collected in the operating sheds of 3 farms and 3 distributors, totaling 17 samples that were analyzed using the sedimentation technique with adapted centrifuge-flotation to identify the presence of parasitic agents. The survey found that 526 inspections were carried out on rural properties to investigate food supplied to ruminants, 98.9% of which came from active surveillance. The characterization made it possible to identify the profile of the inspected breeding establishments, with a predominance of: (i) beef cattle farming (54.8%); (ii) extensive breeding system (56.7%); (iii) cattle as the most exploited ruminant species (88.4%); and, (iv) feeding of ruminants with pasture associated with concentrates and / or supplements of different types (60.3%). The presence of poultry litter on the property was registered in 18.3% of inspections and in 1% the use of this bed in the feeding of ruminants was verified. The analysis of the bovine feed sample collected on the property with suspected supply of poultry litter confirmed the presence of non-calcined bones, non-hydrolyzed feathers and blood. Thus, the procedures for sanitation of the property were adopted as described in the current legislation: interdiction of the property, identification of the animals that consumed the poultry litter, complementary visits to the property until laboratory confirmation and slaughter of the animals involved with the removal and disposal of specific risk materials. Regarding the socioeconomic, productive and health profile of poultry farms in the hinterland Maranhão region, there was a predominance of: (i) male gender; (ii) age range from 41 to over 50 years; (iii) with high school education; (iv) have been in business for more than five years; (v) not participating in associative entities; (vi) poultry farming is the main source of income; (vii) the birds remain for five to ten days in the distributors and 41 to 50 days in the farms; (viii) use an intensive farming system; (ix) used the poultry litter to fertilize the crop and those who marketed this by-product are unaware of its final destination; (x) know the risks of using poultry litter to feed these animals. Parasitological examination of poultry litter showed the presence of eggs and larvae of nematodes and coccids in 47.05% and 29.41% of the samples, respectively. The morphological analysis of the oocysts found the following species: Eimeria maxima (38.71%); Eimeria tenella (22.58%); Eimeria necatrix (19.35%), all of them important for poultry health, not posing any problems for ruminants. It is concluded that despite the prohibition, the use of poultry litter to feed cattle in the State of Maranhão is still practiced, thus emphasizing the importance of surveillance actions on properties with the creation of ruminants associated with health education activities, as well as such as the importance of controlling poultry litter to ensure its proper disposal and mitigate the risk of introducing Bovine Spongiform Encephalopathy