Time trends and epidemiological patterns of perinatal lamb mortality in Norway.

Background: Perinatal mortality is a major cause of loss in the sheep industry. Our aim was to explore time trends in crude population stillbirth and neonatal mortality rates in Norway. We used data on 6,435,715 lambs from flocks enrolled in the Norwegian Sheep Recording System (NSRS) from 2000 through 2010 for descriptive analysis of trends.

Ewe characteristics associated with neonatal loss in Norwegian sheep.

A case-control study was conducted to identify ewe characteristics that affect the risk of a ewe losing at least one lamb during the first 5 days post lambing. Data were from a national sheep registry, and only ewes that lambed in the spring of 2010 belonging to flocks that reported disease events were included. Ewes registered with abortion or stillbirth were excluded.

Short-term and long-term outcomes of ewes and their offspring after elective cesarean section.

Postoperative outcomes of animals that have undergone cesarean delivery have been reported previously; however, in most studies results were influenced by a combination of surgery per se and the preoperative condition of the animal, which was frequently impaired because of the presence of dystocia. To evaluate the effects of the cesarean section itself we conducted a matched cohort study comparing postpartum complications and future reproductive performance of 162 ewes subjected to elective cesarean section and 162 ewes that had an unassisted vaginal delivery. Survival and subsequent growth of their lambs were also compared.

Housing conditions and management practices associated with neonatal lamb mortality in sheep flocks in Norway.

A study was conducted in order to obtain information about sheep farms in Norway and to identify housing and management characteristics that were risk factors for neonatal mortality of lambs 0-5 days of age. A questionnaire was submitted to sheep farmers, who provided demographic data and information on sheep housing conditions and feeding and management practices. Our description of farms is based on the questionnaire responses received from 2260 farmers.

Reproductive performance, udder health, and antibiotic resistance in mastitis bacteria isolated from Norwegian Red cows in conventional and organic farming.

Background: The objectives of this study were to investigate whether there were differences between Norwegian Red cows in conventional and organic farming with respect to reproductive performance, udder health, and antibiotic resistance in udder pathogens.

Methods: Twenty-five conventional and 24 organic herds from south-east and middle Norway participated in the study. Herds were matched such that geographical location, herd size, and barn types were similar across the cohorts.

Individual animal risk factors for clinical mastitis in meat sheep in Norway.

An m:n matched case-control study was conducted to identify risk factors for ovine clinical mastitis (CM). Data were from a national sheep registry and only ewes that lambed in the spring of 2004 were included. Eligible cases (n = 2857) and controls (n = 76,716) from 1056 flocks of meat sheep were matched on flock and conditional logistic regression was used for analysis of the data.

Clinical mastitis in ewes; bacteriology, epidemiology and clinical features.

Background: Clinical mastitis is an important disease in sheep. The objective of this work was to identify causal bacteria and study certain epidemiological and clinical features of clinical mastitis in ewes kept for meat and wool production.

Methods: The study included 509 ewes with clinical mastitis from 353 flocks located in 14 of the 19 counties in Norway.

Deletion of pT181-like sequence in an smr-encoding mosaic plasmid harboured by a persistent bovine Staphylococcus warneri strain.

Objectives: The aim was to study the persistence and characteristics of Staphylococcus warneri strains resistant to quaternary ammonium compounds (QACs), including sequencing and analysis of two plasmids proved to carry the smr gene.

Methods: During a 3.5 year period quarter milk samples were collected on three occasions from all lactating cows in a dairy herd.

Widespread distribution of disinfectant resistance genes among staphylococci of bovine and caprine origin in Norway.

We demonstrate here a widespread distribution of genes mediating efflux-based resistance to quaternary ammonium compounds (QACs) in staphylococci from unpasteurized milk from 127 dairy cattle herds and 70 dairy goat herds. QAC resistance genes were identified in 21% of the cattle herds (qacA/B, smr, qacG, and qacJ) and in 10% of the goat herds (qacA/B and smr). Further examination of 42 QAC-resistant bovine and caprine isolates revealed the following genes: qacA/B (12 isolates) was present in four different species of coagulase-negative staphylococci (CoNS), smr (27 isolates) was detected in eight different CoNS species and in Staphylococcus aureus on a previously reported plasmid (pNVH99), qacG (two isolates) was detected on two plasmids (pST94-like) in Staphylococcus cohnii and Staphylococcus warneri, and qacJ (two isolates) was found in Staphylococcus hominis and Staphylococcus delphini on a plasmid (pNVH01) previously found in equine staphylococci.

Genetic diversity of Staphylococcus aureus isolated from ovine intramammary infections in Norway.

Three hundred and eighty-four Staphylococcus aureus isolates obtained from mammary secretions from 332 ewes kept for meat production were typed by pulsed-field gel electrophoresis (PFGE). The ewes were from 242 flocks located in 13 counties distributed in four regions of Norway. In total, 64 different pulsotypes were identified, 31 of these were represented by a single isolate.

Novel plasmid-borne gene qacJ mediates resistance to quaternary ammonium compounds in equine Staphylococcus aureus, Staphylococcus simulans, and Staphylococcus intermedius.

We identified a novel plasmid-borne gene (designated qacJ) encoding resistance to quaternary ammonium compounds (QACs) in three staphylococcal species associated with chronic infections in four horses. qacJ was located on a 2,650-bp plasmid (designated pNVH01), a new member of the pC194 family of rolling-circle replication plasmids. The 107-amino-acid protein, QacJ, showed similarities to known proteins of the small multidrug resistance family: Smr/QacC (72.