ABSTRACT
Mastitis is the most devastating economic disease in dairy cattle. Mastitis in dairy cattle frequently occurs during the dry period or during early lactation. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus)are the main causative agents of mastitis in India. S. aureus can form microabscesses in the udder and develop a subclinical form of mastitis. This bacterial property hinders an effective cure during the lactation period. Antimicrobials used for treatments have a short half-life at the site of action because of frequent milking; thereforethey are unable to maintain the desired drug concentration for effective clearance of bacteria. We demonstrated the potential of ciprofloxacin-encapsulated nanocarriersthat can improve the availability of drugs and provide an effective means for mastitis treatment. These drug-loaded nanoparticles show low toxicity and slow clearance from the site of action. Antimicrobial activity against clinical strains of E. coli and S. aureus showed that the zone of inhibition depended on the dose (0.5 mg to 2 mg/mL nanoparticle solution from 11.6 to 14.5 mm and 15 to 18 mm). These nanoparticles showed good antimicrobial activity in broth culture and agar diffusion assay against bacteria.
ABSTRACT
Mastitis is a multi-etiological complex disease of dairy cows and negatively affects the quality and quantity of milk. Milk is a nutritious food for human being; milk quality is negatively affected by intramammary infection of dairy cows. A total of 300 milk samples were collected from mastitis dairy cows irrespective of parity and stage of lactation, 235 (78.33%) samples were culturally positive and yielded 1,100 bacterial isolates. Staphylococcus aureus was found to be the prime etiological agent involved in the mastitis of dairy cows, followed by Escherichia coli and other environmental pathogens. On the molecular characterization of isolates obtained from the milk culture, various toxic genes such as nuc, seb, hla, stx1, stx2, hly, and Sagl were found on different isolated bacteria. Milk somatic cell counts (SCC) were found to be directly related to the severity of mastitis. On drawing the SCC correlation with milk components, it was found that SCC had a significant negative correlation with fat, lactose, solid not fat (SNF), and ash. It was concluded that mastitis-affected milk contains numerous pathogenic bacteria, toxins, and reduced milk quality, which is unfit for human consumption.
ABSTRACT
Fast and precise diagnosis of infectious and non-infectious animal diseases and their targeted treatments are of utmost importance for their clinical management. The existing biochemical, serological and molecular methods of disease diagnosis need improvement in their specificity, sensitivity and cost and, are generally not amenable for being used as points-of-care (POC) device. Further, with dramatic changes in environment and farm management practices, one should also arm ourselves and prepare for emerging and re-emerging animal diseases such as cancer, prion diseases, COVID-19, influenza etc. Aptamer - oligonucleotide or short peptides that can specifically bind to target molecules - have increasingly become popular in developing biosensors for sensitive detection of analytes, pathogens (bacteria, virus, fungus, prions), drug residues, toxins and, cancerous cells. They have also been proven successful in the cellular delivery of drugs and targeted therapy of infectious diseases and physiological disorders. However, the in vivo application of aptamer-mediated biosensing and therapy in animals has been limited. This paper reviews the existing reports on the application of aptamer-based biosensors and targeted therapy in animals. It also dissects the various modifications to aptamers that were found to be successful in in vivo application of the aptamers in diagnostics and therapeutics. Finally, it also highlights major challenges and future directions in the application of aptamers in the field of veterinary medicine.
