The role of particular virulence factors of Trueperella pyogenes that determine different pyogenic infections among domestic animals is poorly understood. Eight putative virulence genes and genotype profiles of 71 isolates were investigated among different clinical manifestations in domestic animals. The most common genes were plo (71/71 = 100·0%), fimA (70/71 = 98·6%), nanP (56/71 = 78·9%), fimE (53/71 = 74·6%), fimC (46/71 = 64·8%) and nanH (45/71 = 63·4%), whereas plo/fimA/fimE/fimC/nanH/nanP (17/71 = 23·9%), plo/fimA/fimE/nanH/nanP (13/71 = 18·3%), and plo/fimA/fimE/fimC/nanP (11/71 = 15·5%) were the most frequent genotypes. Studies involving virulence factors are critical in the investigation of molecular epidemiology, pathogenicity, and hypothetical differences in the virulence among T. pyogenes strains from different geographical areas.

Tuberculosis remains as the world’s biggest threat. In 2014, human tuberculosis ranked as a major infectious disease by the first time, overcoming HIV death rates. Bovine tuberculosis is a chronic disease of global distribution that affects animals and can be transmitted to humans by the consumption of raw milk, representing a serious public health concern. Despite the efforts of different countries to control and eradicate bovine tuberculosis, the high negative economic impact on meat and milk production chains remains, given the decreased production efficiency (approximately 25%), the high number of condemned carcasses, and increased animal culling rates. This scenario has motivated the establishment of official programs based on regulations and diagnostic procedures. Although Mycobacterium tuberculosis and Mycobacterium bovis are the major pathogenic species to humans and bovines, respectively, nontuberculous mycobacteria within the Mycobacterium genus have become increasingly important in recent decades due to human infections, including the ones that occur in immunocompetent people. Diagnosis of mycobacteria can be performed by microbiological culture from tissue samples (lymph nodes, lungs) and secretions (sputum, milk). In general, these pathogens demand special nutrient requirements for isolation/growth, and the use of selective and rich culture media. Indeed, within these genera, mycobacteria are classified as either fast- or slow-growth microorganisms. Regarding the latter ones, incubation times can vary from 45 to 90 days. Although microbiological culture is still considered the gold standard method for diagnosis, molecular approaches have been increasingly used. We describe here an overview of the diagnosis of Mycobacterium species in bovine milk.

No abstract

No abstract

No abstract

We investigated the genes kpsMTII, iucD, sfaDE, afaBC, papA and papC, (proposed to be involved in extra‐intestinal pathogenic Escherichia coli—ExPEC), phylogroup classification and the in vitro swimming and swarming motility in 50 E. coli isolated from bovine mastitis with different clinical severity scores (mild, moderate and severe). The aforementioned genes were detected in 12 (n = 12/50; 24·0%) isolates. kpsMTII and iucD were the most frequent genes identified in six (n = 6/50; 12·0%) and four (n = 4/50; 8·0%) of the isolates, respectively. In only one (n = 1/50; 2·0%) isolate, more than one gene was simultaneously identified: iucD and kpsMTll were detected whereas sfaDE and afaBC were not detected. Mild, moderate and severe clinical signs were observed in 40·0% (n = 20/50), 28·0% (n = 14/50) and 32·0% (n = 16/50) of the cases. Commensal phylogroups B1 (n = 19/50; 38·0%) and A (n = 19/50; 38·0%) were prevalent; whereas pathogenic phylogroups B2 and D were observed in only 10·0% (n = 5/50). Swarming and swimming motilities were observed in 90·0% (n = 45/50) and 68·0% (n = 34/50) of the isolates, respectively; and there was a significant association (P = 0·0036) between swarming motility and severe clinical cases (score 3). To the best of our knowledge, this is the first study where clinical severity of bovine mastitis cases and the genes proposed to classify ExPEC were assessed in relation to swarming and swimming motility. Significance and Impact of the Study Escherichia coli is classified as extra‐intestinal (ExPEC) when strains contain at least two of the genes kpsMTII, iucD, sfaDE, afaBC and papA and/or papC. We investigated in vitro motility and the presence of these genes in 50 E. coli isolated from bovine mastitis with different clinical scores (mild, moderate and severe). Clinical severity was not associated with the genes studied. Swarming motility was associated with severe cases (score 3) of clinical mastitis. Results of this study contribute to a better understanding of the factors that determine the severity of clinical mastitis.

Bovine dermatophilosis is a dermatitis characterized by typical focal or localized lesions with “paintbrush” aspect and occasionally as disseminated cutaneous disease. We report the case of a one-year-old Nelore female with history of chronic cutaneous disseminated lesions that appeared immediately after a rainfall period. Serous to purulent exudates, hair with tufted appearance, hyperkeratotic, non-pruritic, hardened, yellowish to brown, and coalescent crusty lesions were observed distributed all over its body. Removal of the crusts revealed ulcerated or hemorrhagic areas, with irregular elevated crusts like “paintbrush”. Microbiological diagnosis enabled the identification of a microorganism, the Dermatophilus congolensis. Despite disseminated and chronic lesions, we obtained a successful therapy with parenteral therapy using long-acting tetracycline based on modified in vitro disk diffusion test. The present report highlights success therapy in uncommon generalized bovine dermatophilosis with selection of first-choice drugs based on modified in vitro susceptibility test, and need of responsible use of antimicrobials in livestock.

Although the tuberculin test represents the main in vivo diagnostic method used in the control and eradication of bovine tuberculosis, few studies have focused on the identification of mycobacteria in the milk from cows positive to the tuberculin test. The aim of this study was to identify Mycobacterium species in milk samples from cows positive to the comparative intradermal test. Milk samples from 142 cows positive to the comparative intradermal test carried out in 4,766 animals were aseptically collected, cultivated on Lowenstein-Jensen and Stonebrink media and incubated for up to 90 days. Colonies compatible with mycobacteria were stained by Ziehl-Neelsen to detect acid-fast bacilli, while to confirm the Mycobacterium genus, conventional PCR was performed. Fourteen mycobacterial strains were isolated from 12 cows (8.4%). The hsp65 gene sequencing identified M. engbaekii (n=5), M. arupense (n=4), M. nonchromogenicum (n=3), and M. heraklionense (n=2) species belong to the Mycobacterium terrae complex. Despite the absence of M. tuberculosis complex species in the milk samples, identification of these mycobacteria highlights the risk of pathogen transmission from bovines to humans throughout milk or dairy products, since many of mycobacterial species described here have been reported in pulmonary and extrapulmonary diseases both in immunocompetent and immunocompromised people.