phenylephrine-hydrochloride and Mastitis

Staphylococcus aureus is an opportunistic pathogen in dairy ruminants where it is found in healthy carriage and can be a major cause of mastitis. A better knowledge of the host-pathogen interactions is needed to tackle this serious animal health problem. This study aimed at identifying S. aureus proteins differentially expressed by S. aureus in nasal colonization versus mastitis. Serological proteome analysis (SERPA) was used to examine protein samples prepared from culture supernatants of S. aureus strains originally isolated from gangrenous mastitis and nasal carriage (O11) or subclinical mastitis (O46) and to compare patterns of immune-reactive proteins. These staphylococcal proteins were revealed by sera obtained from ewes suffering from S. aureus mastitis and by sera obtained from healthy nulliparous ewes (i.e. no lactation and no mastitis or other symptoms) that were nasally colonized by S. aureus. Altogether 49 staphylococcal immune-reactive proteins were identified in this study. Patterns of proteins revealed by sera from infected- or healthy carrier- animals were comparable and analysis singled out one immune-reactive protein, N-acetylmuramyl-L-alanine amidase, which was recognized by each of the 6 sera from infected animals, when tested individually, and not by the sera of healthy carriers. This is the first study that compares the S. aureus seroproteome in colonization versus mastitis context in ruminants. These results open avenues for studies aiming at a better understanding of the balance between infection and commensal lifestyle in this opportunistic pathogen and at new prevention strategies.

Topics: Animals; Bacterial Proteins; Carrier State; Female; Mastitis; N-Acetylmuramoyl-L-alanine Amidase; Nose; Proteome; Sheep; Sheep Diseases; Sheep, Domestic; Staphylococcal Infections; Staphylococcus aureus

A comparison was made between the results of phage and lysogenic typing of S. aureus strains isolated during several outbreaks of staphylococcal infection and S. aureus cultures isolated from the same carriers at different periods. The study of the groups of strains having the same origin showed that the differences in the number of reactions were more pronounced in lysogenic typing than in phage typing. For this reason lysogenic typing can be recommended only for the identification of those strains which cannot be identified with the use of the phages of the International Basic Set. The results of the experiments with induced phages proliferating in a restriction-defective strain indicated that restriction and modification were mainly responsible for the specificity of lytic reactions.

Topics: Animals; Bacteriophage Typing; Bronchi; Carrier State; Chickens; Feces; Female; Food Microbiology; Humans; Infant, Newborn; Infant, Newborn, Diseases; Lysogeny; Mastitis; Nose; Poultry Diseases; Pregnancy; Staphylococcal Food Poisoning; Staphylococcal Infections; Staphylococcus aureus; Staphylococcus Phages; Synovitis

Topics: Animals; Antigens, Bacterial; Cattle; Cell Wall; Columbidae; Dogs; Female; Horses; Humans; Immunodiffusion; Mastitis; Mink; Nose; Polysaccharides, Bacterial; Precipitins; Pregnancy; Rabbits; Serotyping; Staphylococcus; Swine; Teichoic Acids