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M M Chengappa

Publications and source records attributed to M M Chengappa.

103 records · Page 6Linked to original sources
PubMed1984

Effect of pH, temperature and media on acid and alkaline phosphatase activity in "clinical" and "nonclinical" isolates of Bordetella bronchiseptica.

Twenty-two isolates of Bordetella bronchiseptica were studied to determine the effects of pH, incubation temperature and type of media on peak acid and alkaline phosphatase activity. The pH optimum for alkaline phosphatase activity was 9.0 for all of the isolates tested. The pH optimum for acid phosphatase activity was 5.8 for 67% of the isolates and 4.8 for 33%. All of the isolates showed peak phosphatase activity at 37 degrees C. No preference was shown in 35% of the isolates between the types of media tested; however, 40% preferred tryptose broth, 20% preferred nutrient broth and 5% preferred brain-heart infusion broth. No relationship was shown between phosphatase activity and the mouse lethality of the isolates.

Acid Phosphatase↗
PubMed1982

Capsular and somatic types of Pasteurella multocida from rabbits.

Capsular and somatic serotyping was performed on 79 cultures of Pasteurella multocida from rabbits. Of these isolates, 74 were capsular type A as determined by the staphylococcal hyaluronidase decapsulation test and five were type D by the acriflavine flocculation test. Somatic type 12 was the dominant serotype, and the remainder (type 1, 3, 4 and 11) were less frequent as determined by the gel diffusion precipitin test. This report is in general agreement with other recent reports with rabbit isolates and collectively they provide important serotype and epizootiological information that will be useful in the control and prevention of rabbit pasteurellosis.

Animals↗
PubMed1980

Hyaluronidase production by type B Pasteurella multocida from cases of hemorrhagic septicemia.

Seventy-four cultures of Pasteurella multocida representing all four capsular types, A, B, D, and C, from various animal species and diseases were examined for the production of hyaluronidase by two procedures. In one, hyaluronidase production was determined by the depolymerization of streptococcal capsular hyaluronic acid, and in the other, production was determined by degradation of sodium hyaluronidate in a solid culture medium. Hyaluronidase production was only demonstrated in the 13 type B cultures that had been recovered from cases of hemorrhagic septicemia.

Animals↗
PubMed1980

Production and characterization of streptomycin dependent mutants of Pasteurella multocida from bovine haemorrhagic septicaemia.

A large number of streptomycin dependent mutants were produced from bovine haemorrhagic septicaemia strains of Pasteurella multocida. The mutants required a minimum concentration of 25-50 microgram/mL streptomycin for growth and tolerated a concentration of 200 mg/mL. These mutants were avirulent to mice, when inoculated alone, but some mutants killed mice when inoculated with streptomycin. Biochemically all mutants were uniform and similar to the wild type. Most mutants were stable, but a few produced streptomycin independent revertants. The rate of reversion varied with each mutant. Most revertants were highly virulent for mice, some totally avirulant and a few relatively avirulent.

Animals↗
PubMed1980

A streptomycin dependent live Pasteurella multocida vaccine for the prevention of rabbit pasteurellosis.

A culture of Pasteurella multocida was isolated from a rabbit exhibiting clinical signs of respiratory pasteurellosis. Organisms from this culture were incubated in the presence of the mutagen n-methyl-n'-nitro-n-nitrosoguandine in order to obtain a streptomycin dependent mutant. A live vaccine was prepared from this mutant, and healthy pasteurella-free rabbits were vaccinated either by intranasal or subcutaneous administration. Either method provided complete protection against homologous, wild-type challenge as evidenced by absence of clinical signs or gross pathology and failure to isolate the organism from mucous secretions of tissues from vaccinated individuals.

Animals↗
PubMed1977

Demonstration of bacteriocin activity in bovine and bison strains of Pasteurella multocida.

Of 33 strains of Pasteurella multocida examined, 14 showed bacteriocin activity and 17 were susceptible to bacteriocin. The activity was increased by about twofold if the cultures were induced with ultraviolet radiation; however, no increase in bacteriocin activity was observed if the potential producer strains were induced with mitomycin C. The bacteriocin activity of potential producer strains was increased if CaCl2 was incorporated in the medium. The patterns of bacteriocin susceptibility indicate that these substances may ultimately contribute to a typing scheme for the species. An extra-chromosomal genetic element was not detected when a potential producer strain was not detected when a potential producer strain was tested by the dye-buoyant density gradient method. This fact suggests that the genetic material responsible for bacteriocin activity in P multocida is located on the host chromosome proper.

Animals↗
PubMedDate not supplied

Comparative evaluation of two surgical scrub preparations in cattle.

One hundred seventeen cattle that had undergone surgery were assigned randomly to two preoperative skin preparation protocols. Group 1 (60 animals) skin preparation was with povidoneiodine soap and isopropyl alcohol, whereas group 2 (57 animals) had skin preparation with chlorhexidine gluconate and isopropyl alcohol. Quantitative microbial culture plates were used to estimate the number of colony forming units (CFUs) before skin preparation (prescrub), after skin preparation (postscrub), after surgery (postoperative), and in room air (environment). A significant decrease in CFU occurred postscrub for both skin preparations (P < .05). Chlorhexidine and alcohol preparation resulted in significantly fewer CFUs (LSMean +/- SE = 2.79 CFU +/- 1.74) and a greater percentage reduction in CFUs (98.64% +/- 2.01) postscrub than providone and alcohol (LSMean +/- SE = 10.27 CFUs +/- 1.51, 93.29% +/- 1.85); (P < .005). Group 2 had a significantly higher frequency of negative cultures postscrub (49.1%) compared with group 1 (18.3%) (P < .001). The number of postoperative CFUs were not significantly different between the two treatment groups. Wound infection frequency for clean surgical procedures was not significantly different between the two skin preparation protocols (group 1 = 9.8%, group 2 = 10.7%), however, infection frequency was significantly higher for surgical procedures with a ventral abdominal approach (5 of 14, 35.7%,) compared with a flank approach (1 of 41, 2.4%) or other approaches (orthopedic procedures) (1 of 16, 6.3%) (P < .05). Both skin preparation protocols were effective and safe in decreasing the skin microflora population of cattle before surgery and although preparation with chlorhexidine gluconate and alcohol resulted in less CFUs immediately postscrub, the frequency of surgical wound infection was similar for both protocols.

1-Propanol↗
PubMedDate not supplied

Salmonella enteritidis infection in two species of psittaciformes.

In 1990, Salmonella enteritidis phage type 4 was recovered from two young (less than 20-week-old) lilac-crowned Amazon parrots (Amazona finschi Schlater), one in Tennessee and one in Kansas. The parrot from Tennessee was treated for a plugged naris and anorexia before the S. enteritidis infection was discovered. The parrot from Kansas exhibited signs of septicemia and died within 24 hours of examination. An apparently healthy green-cheeked conure (Pyrrhura molinae) on the same premises as the parrot from Tennessee was positive for S. enteritidis phage type 4 on a cloacal swab. These are the first reported cases of avian infection with S. enteritidis phage type 4 in the United States. Because several infectious agents were present simultaneously in the Amazon parrots, it was difficult to determine the precise role of S. enteritidis phage type 4 in the clinical presentations.

Animals↗