ABSTRACT
The objective of the present study was to determine whether there was an association between in the in vitro antimicrobial sensitivity test results of subclinical mastitis pathogens and bacteriological cure following intramammary treatment using a combination of nafcillin, penicillin, and streptomycin [NPS]. Eighty-six intramammary pathogens from 43 cows were examined in this study. Most intramammary infections were due to coagulase-negative staphylococci, coliforms, and environmental streptococci. The antibiotic sensitivity to NPS was determined using the Kirby-Bauer disc diffusion method. Bacteriological cure rates for sensitive, intermediate, and resistant isolates in the standard treatment group [3 intramammary infusions of NPS once daily] were 84.44, 88.9, and 100%, respectively. These figures in the extended treatment group [6 intramammary infusions of NPS once daily] were 100% for the 3 categories. Bacteriological cure was not associated with the sensitivity test result. Based on this study, Kirby-Bauer sensitivity test results were not useful as predictors of the bacteriological outcome of subclinical mastitis treated with intramammary NPS
ABSTRACT
In this study 130 bulk tank milk samples which were delivered to the Pegah Pasturisation Factory in Mashhad were collected randomly during the summer months. Samples were firstly enriched in modified trypticase soy broth containing novobiocin, followed by plating onto sorbitol MacConkey agar supplemented with cefixine and potassium tellurite for isolation of Escherichia coli O157:H7. Consequently the suspected non-sorbitol fermenting [NSF] colonies were confirmed by biochemical tests as Escherichia coli and then were used for multiplex-PCR assay, using primers specific for O157 and H7 antigens genes and then primers specific for stxl and stx2 genes. NSF Escherichia coli colonies were recovered from 8 samples, and in multiplex-PCR assay one sample [0.77%] was confirmed as Escherichia coli O157:H7. The second multiplex PCR assay showed that the isolate was harboring the stx2 gene. The PCR assay used in this study may be a possible alternative to immunological assays which detect somatic and flagellar antigens. Besides, this procedure determines the potential of isolates for toxin production
ABSTRACT
The objective of the present study was to determine whether there was an association between the in vitro antimicrobial susceptibility test results of subclinical mastitis pathogens and bacteriological outcomes of intramammary treatments using cefquinome. A total of 110 intramammary pathogens from 51 cows were assessed in this study. Most intramammary infections were due to coagulase-negative staphylococci, environmental streptococci, and coliforms. The antimicrobial susceptibility to cefquinome was determined using the Kirby-Bauer disc diffusion method. Bacteriological cure rates for the sensitive, intermediate, and resistant isolates in the standard treatment group [three intramammary infusions of 75 mg cefquinome at 16 h intervals] were 82.4%, 90%, and 87.5%, respectively. These figures in the extended treatment group [six intramammary infusions of 75 mg cefquinome at 16 h intervals] were 83.3%, 100%, and 100%, respectively. Treatment outcomes were not associated with the results of sensitivity tests in the standard group. However, in the extended group, the probability of a bacteriological cure was lower in quarters from which cefquinome-sensitive pathogens were isolated than the quarters from which intermediate or resistant pathogens were isolated. Based on this study, the Kirby-Bauer susceptibility test result is a poor predictor for the bacteriological cure of subclinical mastitis treated with intramammary cefquinome
Subject(s)
Animals , Female , Mastitis, Bovine/drug therapy , Cephalosporins , Microbial Sensitivity Tests , In Vitro TechniquesABSTRACT
A prospective study was conducted to investigate the difference in levels of some blood constituents between fertile and infertile cows, A total of 40 dairy cows were selected at random from a dairy farm. Serum samples were collected three times on 5 +/- 3, 30 +/- 3 and 58 +/- 3 days postpartum. Serum glucose, urea nitrogen [UN], cholesterol, albumin, total protein, calcium, inorganic phosphorus and aspartate aminotransferase [AST] were measured for each sample. Cows were divided into two categories; those which conceived at either the first or second insemination [group 1] and those which conceived >/= 3 inseminations [group 2]. Seventy percent [28 of 40] of the cows conceived at first or second insemination and 30% [12 of 40] needed 3 or more inseminations. Results showed that calcium [2.34 vs. 2.17 mmol/L] and inorganic phosphorus [1.84 vs. 1.42 mmol/L] were significantly [P<0.05] higher in the group 1 cows at second stage of sampling