Global Emergence of Trimethoprim/Sulfamethoxazole Resistance in Stenotrophomonas maltophilia Mediated by Acquisition of sul Genes

The first sul2 genes have been found in S. maltophilia from several different countries

Supplementation of pregnant cows with protected proteins when fed tropical forage diets

Native pastures in the dry tropics rapidly decline in digestibility and N content with the onset of the dry season. N supplementation is offered as a management strategy to overcome the dry season nutritional deficit. This deficit occurs despite an abundance of dry standing pasture and one of the susceptible groups of cattle is lactating cows

The effect of genotype and zeranol implantation on performance of steers grazing Mitchell grass pastures in north-west Queensland

[Summary]: Steers of seven different genotypes were purchased from six locations in north-west Queensland and their liveweight performance was compared while grazing Mitchell grass pastures. Only small differences were recorded in liveweight gain between steers containing the approximate breed components of Africander 3 Shorthorn 5, Sahiwal 3 Shorthorn 5, Santa Gertrudis, Brahman 4 British 4, and Brahman 6 British 2. The Bos indicus infused steers had annual liveweight gains of 135 compared with 110kg / head / year in the comparable age Hereford group. Zeranol implantation gave 6% advantage in liveweight gain durin the first 84 d post implantation. This response was consisten across genotype groups. Final liveweight of treated steers was 3% heavier than of untreated steers, although zeranol treatment was given 444 d before slaughter

Seasonal effects of dosing cattle with monensin sodium in the dry tropics

Monensin sodium is one of the few products available which will successfully manipulate rumen fermentation over an extended period of time. This experiment studied the metabolic effect of dosing cattle with monensin sodium during the dry and wet seasons in the dry tropics

The effect of trenbolone acetate on liveweight changes and pregnancy rates in zebu crossbred heifers grazing tropical pastures

Trenbolone acetate (androst-4, 9(10), 11 trien-3-one, -17 acetate) (TBA) is one of the few anabolic compounds available for use in female cattle. Best (1972) demonstrated that the growth rate of pasture fed Bos taurus heifers was increased by 38% when treated with TBA. However, Heitzman et al (1977) reported that TBA caused anoestrus in dry dairy cows. The present study used Zebu crossbred heifers to examine the effect of TBA on liveweight gain and pregnancy rates

The effect of three different nitrogen based supplements on the utilization of tropical forage diets by zebu crossbred steers

Thirty-two Bos indicus crossbred steers were offered ad libitum a basal diet of low quality tropical native pasture hay. Supplements of urea (US), urea and formaldehyde cottonseed meal (US+PP) or urea, soyabean meal and maize (UPM) were compared in a 64 day pen feeding study. The unsupplemented controls lost 27kg and those fed urea lost 14kg. Liveweight gains of 18kg and 11kg were observed in treatments US+PP and UPM respectively. The liveweight responses were related to a 60% increase in roughage intake and the increased nutrient supply from supplemental protein and energy

Clinical utilization of bacteriophages: a new perspective to combat the antimicrobial resistance in Brazil

Due to the emergence of multi-drug resistant bacteria, and the evident limitation in therapeutic options, alternatives to combat bacterial infections have been sought. One of these is phage therapy, which is the use of bacterial viruses to kill pathogenic bacteria responsible for the infection. These viruses called bacteriophages are very abundant organisms in the world and are harmless to humans. There are several advantages in using phage therapy, especially against multi-drug resistant pathogens, which tend to be dominated by individual strains. The advantages include fewer collateral effects such as lower disturbance of gut microbiota and less antimicrobials consumption, which itself leads to reducing antibiotic resistance rates. Unfortunately, few clinical studies have been initiated in Brazil and this area is little explored in our country. This manuscript describes clinical evidence of successful phage utilization on pathogens considered a threat in Brazil, highlighting the benefits of a possible phage utilization as an important tool to combat antimicrobial resistance in our country

OXA-1 β-lactamase and non-susceptibility to penicillin/β-lactamase inhibitor combinations among ESBL-producing Escherichia coli

Background ESBL-producing Escherichia coli have expanded globally since the turn of the century and present a major public health issue. Their in vitro susceptibility to penicillin/inhibitor combinations is variable, and clinical use of these combinations against ESBL producers remains controversial. We hypothesized that this variability related to co-production of OXA-1 penicillinase. Methods During a national study we collected 293 ESBL-producing E. coli from bacteraemias, determined MICs by BSAC agar dilution, and undertook genomic sequencing with Illumina methodology. Results The collection was dominated by ST131 (n = 188 isolates, 64.2%) and bla CTX-M-15 (present in 229 isolates, 78.2%); over half the isolates (159/293, 54.3%) were ST131 with bla CTX-M-15. bla OXA-1 was found in 149 ESBL producers (50.9%) and bla TEM-1/191 in 137 (46.8%). Irrespective of whether all isolates were considered, or ST131 alone, there were strong associations (P < 0.001) between co-carriage of bla OXA-1 and reduced susceptibility to penicillin/inhibitor combinations, whereas there was no significant association with co-carriage of bla TEM-1/191. For piperacillin/tazobactam the modal MIC rose from 2 mg/L in the absence of bla OXA-1 to 8 or 16 mg/L in its presence; for co-amoxiclav the shift was smaller, from 4 or 8 to 16 mg/L, but crossed the breakpoint. bla OXA-1 was strongly associated with co-carriage also of aac(6′)-Ib-cr, which compromises amikacin and tobramycin. Conclusions Co-carriage of OXA-1, a penicillinase with weak affinity for inhibitors, is a major correlate of resistance to piperacillin/tazobactam and co-amoxiclav in E. coli and is commonly associated with co-carriage of aac(6′)-Ib-cr, which narrows aminoglycoside options

Longitudinal genomic surveillance of MRSA in the UK reveals transmission patterns in hospitals and the community.

Genome sequencing has provided snapshots of the transmission of methicillin-resistant Staphylococcus aureus (MRSA) during suspected outbreaks in isolated hospital wards. Scale-up to populations is now required to establish the full potential of this technology for surveillance. We prospectively identified all individuals over a 12-month period who had at least one MRSA-positive sample processed by a routine diagnostic microbiology laboratory in the East of England, which received samples from three hospitals and 75 general practitioner (GP) practices. We sequenced at least 1 MRSA isolate from 1465 individuals (2282 MRSA isolates) and recorded epidemiological data. An integrated epidemiological and phylogenetic analysis revealed 173 transmission clusters containing between 2 and 44 cases and involving 598 people (40.8%). Of these, 118 clusters (371 people) involved hospital contacts alone, 27 clusters (72 people) involved community contacts alone, and 28 clusters (157 people) had both types of contact. Community- and hospital-associated MRSA lineages were equally capable of transmission in the community, with instances of spread in households, long-term care facilities, and GP practices. Our study provides a comprehensive picture of MRSA transmission in a sampled population of 1465 people and suggests the need to review existing infection control policy and practice