a b s t r a c tStorage of goat milk production in cold temperatures is a current Brazilian legislation request, however there is no specification of a limit period for this. The present work aimed to characterize the microbiological characteristics of raw goat milk produced in a specific region of Brazil, as well as the influence of the storage system and period on its quality. Sixtyone samples from 12 goat farms were collected and subjected to analysis to enumerate hygiene indicator microorganisms, psychrotrophics and proteolytic psychrotrophics. The obtained counts were described and compared considering the system and period of storage (ANOVA, Tukey). Despite presenting low counts of mesophiles, the samples presented high counts of other groups and a relevant presence of proteolytics. Samples collected from bulk tanks presented higher counts of mesophiles and psychrotrophics when compared to immersion tanks and freezers (p < 0.05). When stored for a period of 48 h or longer, the counts of mesophiles, coliforms, Escherichia coli and psychrotrophics were also significantly higher when compared to a storage period of 24 h or less (p < 0.05). The results indicate specific problems in goat milk production in the studied area and the need of establishing a period limit for raw goat milk collection in Brazil.

The bacterium Actinobacillus pleuropneumoniae is the etiological agent of Contagious Porcine Pleuropneumonia, a disease responsible for economic losses in the swine industry worldwide. A. pleuropneumoniae is capable of producing proteinaceous exotoxins responsible for inducing hemorrhagic lesions, one of which is ApxI. Few studies have conducted an in-depth evaluation of polymorphisms of the nucleotides that make up the ApxI toxin gene. Here we analyze the polymorphisms of the apxIA gene region of A. pleuropneumoniae serovar 5 isolated from swine in different regions in Brazil and report the results of molecular sequencing and phylogenetic analysis. Analysis of the apxIA gene in 60 isolates revealed the presence of genetic diversity and variability. The polymorphisms in the nucleotide sequences determined the grouping of the Brazilian sequences and five more sequences from the GenBank database into 14 different haplotypes, which formed three main groups and revealed the presence of mutations in the nucleotide sequences. The estimation of selection pressures suggests the occurrence of genetic variations by positive selective pressure on A. pleuropneumoniae in large groups of animals in relatively small spaces. These conditions presumably favor the horizontal dissemination of apxIA gene mutations within bacterial populations with host reservoirs. As a result, the same serovar can demonstrate different antigenic capacities due to mutations in the apxIA gene. These alterations in sequences of the apxIA gene could occur in other areas of countries with intense swine production, which could lead to differences in the pathogenicity and immunogenicity of each serovar and have implications for the clinical status or diagnosis of A. pleuropneumoniae.