The objective of this study was to evaluate the effect of the addition of a phytogenic compounds blend (PHA) containing hydrolyzable tannins, carvacrol and cinnamaldehyde oil in the mineral salt or energy supplement on the rumen microbiota and nitrogen metabolism of grazing Nellore cattle. Eight castrated Nellore steers were distributed in a double Latin square 4 × 4 design, with a 2 × 2 factorial arrangement (two type supplements and the addition or not of PHA) as follows: energy supplement without PHA addition (EW); energy supplement with PHA addition (EPHA); mineral supplement without the addition of PHA (MW); and mineral supplement with PHA addition (MPHA). Steers that received supplements with PHA have a lower ruminal proportion of Valerate (with PHA 1.06%; without PHA 1.15%), a lower ruminal abundance of Verrucomicrobia and a tendency for lower DM digestibility (with PHA 62.8%; without PHA 64.8%). Energy supplements allowed higher ammonia concentrations (+2.28 mg of NH3-N/dL), increased the propionate proportion (+0.29% of total VFA), and showed a tendency to have a higher abundance of Bacteroidetes and a lower abundance of Firmicutes in the rumen. The PHA addition in the supplement did not improve the use of nitrogen in grazing cattle, but negatively affected the diet digestibility.

Background: Porteirinha is endemic for visceral leishmaniasis (VL), with intense disease transmission of the disease. We evaluated the impact of canine euthanasia as a single control measure on the incidence of VL in humans and canines. Methods: A prospective observational cohort study was carried out over four years (1998–2002) in eight of the 12 neighborhoods of the city. The dynamics of canine visceral leishmaniasis (CVL) transmission were evaluated for 2 years, before beginning the screening-culling intervention. The comparative morbidity index (CMI) was used to stratify areas with the greatest risk of CVL, and the spatial distribution of human and canine VL cases was compared using univariate and bivariate K functions. Results: Human cases conglomerated in three neighborhoods. Spatial clusters were detected for CVL in 1998, 2000, and 2001, but not in 1999, when greater spatial dispersion occurred. The screening and culling intervention reduced the number of human VL cases and decreased the incidence of CVL, mainly in neighbor-hoods with a high CMI. Conclusions: The systematic euthanasia of seropositive dogs was shown to be an effective control action of the Program for Control of Visceral Leishmaniasis (PCLV) in Brazil. The fundamental role of domestic dogs in the epidemiological chain of VL was reaffirmed.