Early neonatal lamb mortality: postmortem findings.

An investigation of stillbirth and early neonatal lamb mortality was conducted in sheep flocks in Norway. Knowledge of actual causes of death are important to aid the interpretation of results obtained during studies assessing the risk factors for lamb mortality, and when tailoring preventive measures at the flock, ewe and individual lamb level. This paper reports on the postmortem findings in 270 liveborn lambs that died during the first 5 days after birth. The lambs were from 17 flocks in six counties. A total of 27% died within 3 h after birth, 41% within 24 h and 80% within 2 days. Most lambs (62%) were from triplet or higher order litters. In 81% of twin and larger litters, only one lamb died. The most frequently identified cause of neonatal death was infectious disease (n=97, 36%); 48% (n=47) of these died from septicaemia, 25% (n=24) from pneumonia, 22% (n=21) from gastrointestinal infections and 5% (n=5) from other infections. Escherichia coli accounted for 65% of the septicaemic cases, and were the most common causal agent obtained from all cases of infection (41%). In total, 14% of neonatal deaths resulted from infection by this bacterium. Traumatic lesions were the primary cause of death in 20% (n=53) of the lambs. A total of 46% of these died within 3 h after birth and 66% within 24 h. Severe congenital malformations were found in 10% (n=27) of the lambs, whereas starvation with no concurrent lesions was the cause of death in 6% (n=17). In 16% (n=43) of the lambs, no specific cause of death was identified, lambs from triplet and higher order litters being overrepresented among these cases. In this study, the main causes of neonatal lamb mortality were infection and traumatic lesions. Most neonatal deaths occurred shortly after birth, suggesting that events related to lambing and the immediate post-lambing period are critical for lamb survival.

Rural hospital mass casualty response to a terrorist shooting spree.

BACKGROUND: Civilian mass casualty incidents may occur infrequently and suddenly, and are caused by accidents, natural disasters or human terrorist incidents. Most reports deal with trauma centre management in large cities, and data from small local hospitals are scarce. A rural hospital response to a mass casualty incident caused by a terrorist shooting spree was evaluated. METHODS: An observational study was undertaken to evaluate the triage, diagnosis and management of all casualties received from the Utøya youth camp in Norway on 22 July 2011 by a local hospital, using data from the hospital's electronic records. Descriptive data are presented for patient demographics, injuries and patient flow. RESULTS: The shooting on Utøya youth camp left 69 people dead and 60 wounded. A rural hospital (Ringerike Hospital) triaged 35 patients, of whom 18 were admitted. During the main surge, the hospital triaged and treated 22 patients within 1 h, of whom 13 fulfilled the criteria for activating the hospital trauma team, including five with critical injuries (defined as an Injury Severity Score above 15). Ten computed tomography scans, two focused assessment with sonography for trauma (FAST) scans and 25 conventional X-rays were performed. During the first 24 h, ten surgical procedures were performed and four chest drains inserted. No patient died. CONCLUSION: Critical deviation from the major incident plan was needed, and future need for revision is deemed necessary based on the experience. Communication systems and the organization of radiological services proved to be most vulnerable.

Persistence of staphylococcal species and genotypes in the bovine udder.

Staphylococci are a major cause of intramammary infections (IMI) in ruminants. The main aim of this study was to investigate staphylococcal IMI in dairy cattle with emphasis on persistence and distribution of staphylococcal species and genotypes. With a sampling interval of 4-8 weeks, over a year, 4030 samples from 206 cows in 4 herds were collected. Coagulase-negative staphylococci (CNS) and Staphylococcus aureus were detected in 13.2% and 4.2% of the samples, respectively. Selected CNS isolates from quarter milk samples were identified to species level using sodA sequencing. Staphylococcus chromogenes (32%) and Staphylococcus simulans (25%) predominated. The proportion of S. chromogenes was greater in primiparous (52%) than in multiparous cows (12%), while the opposite was the case for Staphylococcus epidermidis (6% and 21%, respectively). Isolates from possibly persistent IMI were selected for pulsed-field gel electrophoresis (PFGE). Six staphylococcal species were found to cause persistent IMI; S. aureus, S. chromogenes, S. simulans, S. epidermidis, Staphylococcus haemolyticus and Staphylococcus warneri. It was shown that several pulsotypes (PTs) within each species were associated with persistent infections, but only a few were spread and caused persistent IMI in multiple cows within a herd. Of special interest was the observation that only one, or a few, strains of each species caused persistent IMI in multiple cows within a same herd. This indicates strain differences with respect to transmissibility and pathogenicity.

Pregnancy associated glycoproteins (PAG) in postpartum cows, ewes, goats and their offspring.

Determination of plasma concentrations of pregnancy associated glycoproteins (PAG) has been used for early pregnancy diagnosis in cows. However, this is complicated by the presence of PAG in plasma for an extended period postpartum. The main objective of the present study was to investigate the postpartum elimination rates of pregnancy associated glycoproteins (PAG) in sheep, goats and cows in order to gain background information applicable to the use of PAG for pregnancy diagnosis in domestic ruminants. A second objective was to investigate whether PAG are transferred to the foetus and newborn, by measuring plasma PAG concentrations in calves, lambs and goat kids before and after colostrum feeding. PAG in the blood at parturition were eliminated by a first order process in the cows and ewes, while a two-step log-linear decline occurred in the goats. Estimated postpartum half-life of plasma PAG in the cows and ewes was 9 and 4.5 days, respectively. In the goats, half-lives were 3.6 and 7.5 days in the initial fast and terminal slow phase. Basal levels were reached 80-90 days postpartum in cows. Plasma PAG concentration can be used for pregnancy diagnosis from day 28 after AI, provided that the time interval from calving to AI is >60 days. Using a heterologous antibody RIA, we found 4 ng/mL to be the appropriate cut-off. Due to the presence of PAG residues from the previous gestation, the interval from AI to pregnancy diagnosis should increase by approximately 0.5 days beyond 28 days for each day of AI closer to calving than 60. Measurements in newborn ruminants suggested that PAG enter the foetal blood in utero and that colostral PAG are transferred to the newborn. Following the peak plasma concentration observed 1 day after birth in most of the animals, PAG were rapidly eliminated in a log-linear fashion.

Comparison of Staphylococcus aureus genotypes recovered from cases of bovine, ovine, and caprine mastitis.

Staphylococcus aureus is an important pathogen in domestic ruminants. The main objective of this study was to determine the similarity of epidemiologically unrelated S. aureus isolates from bovine, ovine, and caprine mastitis. By pulsed-field gel electrophoresis, 160 different pulsotypes (PTs) were identified among 905 isolates recovered from 588 herds in 12 counties in Norway. Based on estimates of similarity, using an 80% cluster cutoff, the isolates were assigned to 47 clusters. One cluster included 62% of all the isolates and more than 45% of the isolates from each host species. Twenty-three PTs included isolates from more than one host species; these 23 PTs represented 72% of all the isolates. The six most prevalent PTs included isolates from all host species and contained 45% of the bovine isolates, 54% of the ovine isolates, and 37% of the caprine isolates. Antimicrobial susceptibility testing of 373 of the isolates revealed resistance to penicillin in 2.9% and to streptomycin in 2.4%; only 1.9% were resistant to 1 of the other 11 antimicrobials tested. The results of this study suggest that a small number of closely related genotypes are responsible for a great proportion of S. aureus mastitis cases in cows, ewes, and goats in Norway and that these genotypes exhibit little or no host preference among these species. Selection due to antimicrobial resistance appears not to have contributed to the predominance of these genotypes.

Spread of Staphylococcus aureus resistant to penicillin and tetracycline within and between dairy herds.

One hundred and seven bovine isolates of penicillin and tetracycline resistant Staphylococcus aureus, recovered from 25 different dairy herds in various parts of Norway, were characterized using antimicrobial susceptibility testing, multilocus enzyme electrophoresis, ribotyping, plasmid analysis and serotyping of capsular polysaccharide. Forty-one isolates from one particular herd, 37 isolates from 5 herds that used a common pasture and milking parlour in summer and 21 isolates from 12 herds in 8 different counties belonged to the same strain. The remaining 8 isolates, which originated from herds in 5 different counties, were assigned to 6 different strains. Seven out of these 8 isolates had the same plasmid restriction profile. In conclusion, penicillin and tetracycline resistant S. aureus occurring in dairy herds in Norway mainly seems to represent one particular strain that has achieved widespread distribution or belong to one of several different strains carrying identical plasmids.

Clinical bovine mastitis in Norway.

A brief description of the Norwegian Health Card System for Cattle (NHCSC) is given. The incidence of clinical mastitis (CM) for dairy cows in Norway was determined using NHCSC data recorded from 1992 to 1995. Incidence density (ID) (which included repeated episodes of CM in the same cow) and various measures of risk were estimated. The ID for the entire study period, comprising almost 1.2 million cow-years, was 49 CM episodes per 100 cow-years at risk. Twenty-six percent of the cows with CM experienced at least two episodes of CM in 1 year. For the entire study period (1992-1995), the ID was 30 episodes per 100 cow-years at risk for acute CM (ACM). Annual risk of CM for fixed cohorts of cows that were at risk 1 January the particular year, as estimated by the actuarial method and accounting for the exact time of removal of culled cows, varied between 0.32 (1992) and 0.35 (1994 and 1995). Numerically similar risk estimates were found when using the density method for fixed cohorts. Lactational incidence risk for cows that calved in 1992-1994 varied between 0.32 and 0.34. In herds of a size greater than five cow-years, the crude ID of CM tended to decrease with increasing herd size. The ID of CM varied considerably between counties, and was higher in coastal areas than in inland areas.

Plasmid-borne smr gene causes resistance to quaternary ammonium compounds in bovine Staphylococcus aureus.

Resistance to quaternary ammonium compounds (QAC) in staphylococci is common in hospital environments and has been described in the food industry. Little is known about staphylococcal QAC resistance associated with animal disease, although such disinfectants are widely used in veterinary medicine. In order to investigate the occurrence of QAC resistance in staphylococci isolated from QAC-exposed animals, 32 penicillin- and tetracycline-resistant and 23 penicillin- and tetracycline-susceptible Staphylococcus aureus isolates collected from milk from cows with mastitis during a 4-year period were selected for QAC susceptibility studies and genetic characterization. The isolates originated from four different herds that used a common pasture with a joint milking parlor in the summer. During the pasture season, a teat cream containing the QAC cetyltrimethylammonium bromide had been used daily for more than 10 years for mastitis control. Three of the penicillin- and tetracycline-resistant isolates, which were recovered from three different cows during a 20-month period, were resistant to QAC. Plasmid analysis, PCR, and DNA sequencing revealed a novel plasmid of 2,239 bp containing the smr gene. The plasmid, designated pNVH99, has similarities to small, smr-containing staphylococcal plasmids previously found in human and food isolates. pNVH99 is a new member of the pC194 family of rolling-circle replication plasmids. The three QAC-resistant isolates, as well as 28 of the 29 remaining penicillin- and tetracycline-resistant isolates, were indistinguishable by pulsed-field gel electrophoresis. The study indicates that the occurrence and spread of QAC-resistant S. aureus among dairy cows may be a problem that needs further investigation.

Case-control study of risk factors for clinical mastitis in postpartum dairy heifers.

A case-control study was carried out to evaluate risk factors for clinical mastitis occurring in dairy heifers between 1 and 14 d postpartum. Case and control heifers were matched on herd; the control was the heifer that calved closest in time, before or after, the particular case. Data were analyzed by conditional logistic regression. The final multivariate model included 339 case-control pairs. Blood in the milk, udder edema, teat edema, and milk leakage, all recorded at the time of parturition, were significant risk factors. Purchased heifers and heifers with skin lesions between udder and thigh were not at increased risk of clinical mastitis. Separate analysis of a subgroup of case-control pairs identified teat edema, blood in the milk, and milk leakage at calving as risk factors for clinical mastitis caused by Staphylococcus aureus.

Influence of new infection with bovine virus diarrhoea virus on udder health in Norwegian dairy cows.

A retrospective longitudinal study was conducted to examine whether the exposure of dairy herds to bovine virus diarrhoea virus (BVDV) affected udder health. All Norwegian dairy herds that had experienced a marked increase in the BVDV antibody titres in bulk milk (from a level corresponding to an optical density (OD) <0.25 to >0.55, as determined by an indirect enzyme-linked immunosorbent assay) between two nation-wide herd screening examinations carried out late in 1992 and 1993, respectively, were considered to have been exposed to BVDV during the period between the examinations. The reference group included all dairy herds in which the bulk milk was BVDV antibody-negative or had only very low titres of BVDV antibodies (OD <0.25) each year from 1992 to 1995. The annual incidence rate of clinical mastitis, the bulk-milk somatic-cell count, and the annual rate of culling because of mastitis in the herds, were compared in the year of BVDV exposure (1993) as well as in a period prior to exposure (from 1988 to 1992) and two years following the year of exposure. In herds exposed to BVDV, there was a 7% increase in the incidence rate of clinical mastitis in the year of exposure, as compared with the nonexposed herds. No significant changes attributable to BVDV exposure were observed in the bulk-milk somatic-cell count or in the rate of culling because of mastitis.

Outcome of clinical mastitis in dairy heifers assessed by reexamination of cases one month after treatment.

Heifers that were treated for clinical mastitis prior to parturition or within 14 d postpartum were reexamined approximately 1 mo after treatment. Clinical examination of the heifers and microbiological examination of quarter milk samples were carried out on both occasions. Of the 1000 heifers included in the study, 10.9% were culled within 28 d after treatment. Udder damage caused by mastitis was the only or main reason for culling in 96% of those heifers. In comparison, 4.5% of nonmastitic heifers from the same herds were culled within 30 d postpartum. Twenty-five percent of those heifers that were not culled at d 28 after treatment had at least one nonfunctional quarter at that time. One thousand one hundred twenty-two quarters that were clinically affected at the time of treatment were reexamined; 22% were nonfunctional, 14% were still affected by clinical mastitis, 12% had subclinical mastitis, 5% had a latent infection with coagulase-positive staphylococci or Streptococcus dysgalactiae, and 46% were bacteriologically negative and had a normal cell count at the time of reexamination. High percentages of nonfunctional quarters were observed among those quarters that were infected with Arcanobacterium pyogenes or with coagulase-positive staphylococci at treatment. When all quarters that were clinically affected at treatment were considered, 40% of quarters were cured and were still in lactation at reexamination. Quarters infected with coagulase-negative staphylococci had a higher cure rate than quarters infected with other organisms. At reexamination, clinical signs of thelitis were observed in many of those quarters that were nonfunctional following the episode of clinical mastitis and also in 25% of lactating quarters in which clinical mastitis persisted.

Diagnostic alternatives used by veterinary surgeons for the recording of udder diseases in the Norwegian Health Card System for Cattle.

A questionnaire, in which 7 cases of udder disease were described, was distributed to 890 veterinarians in Norway. They were requested to classify the cases according to the diagnostic alternatives listed in the Norwegian Health Card System for Cattle (NHCSC). The NHCSC recordings are used for progeny testing of bulls, for disease monitoring, and for research purposes. The aim of this study was to evaluate the quality of the recordings for udder diseases. The questionnaire was answered by 633 veterinary surgeons. Four cases of clinical mastitis (CM) with abnormal secretion as well as other clinical signs of inflammation were correctly classified as CM by almost 100% of the veterinary surgeons. A cow in the final stage of lactation, showing no clinical signs except for clots in the milk, was considered not to be a clinical case by more than 25% of the veterinary surgeons. A typical case of subclinical mastitis (SM) was reported as SM by 83% of the veterinary surgeons, and as CM by 16%. A subclinical case with a recent history of clots in the secretion was classified as SM by 66% of the veterinary surgeons, but almost 40% either reported CM as their sole diagnosis or considered the case to be CM in combination with SM. Of the clinical cases, those exhibiting marked local signs of inflammation and a systemic reaction were correctly classified as acute clinical mastitis (ACM) by 96%-98% of the veterinary surgeons. In the NHCSC, the diagnostic alternatives for cases of CM are ACM and chronic clinical mastitis (CCM). One case, for which the diagnosis subacute clinical mastitis was appropriate according to standard definitions, was classified as CCM by 66%, and as ACM by 6%. Based on the information given in the questionnaire, the diagnosis for 2 of the clinical cases could have been either ACM or CCM, and for both cases each of these 2 alternatives was reported by more than 43% of the veterinary surgeons. A teat lesion, which was present together with ACM in one cow, was reported by 91% of the veterinary surgeons.

Polyethylene wear, osteolysis and acetabular loosening with an HA-coated hip prosthesis. A follow-up of 94 consecutive arthroplasties.

We have followed up for a period of seven to nine years 100 consecutive arthroplasties of the hip in which an entirely HA-coated implant had been used. The clinical results were excellent and bony incorporation was extensive in all components. No stem became loose or subsided but five cups were revised because of loosening after 3.8 to 5.5 years, having functioned painlessly and shown radiological ingrowth. Revision procedures because of excessive polyethylene wear have been performed on 18 hips and are planned for six more. Two eroded metal backings with worn-through polyethylene were exchanged; six hips showed metallosis without polyethylene wear-through. There were two cases of granulomatous cysts in the groin and 66 hips had osteolysis located periarticularly, in the greater trochanter or in the acetabulum.

Bacteria associated with clinical mastitis in dairy heifers.

A 1-yr field investigation of clinical mastitis in heifers was carried out in 24 veterinary districts in Norway. Quarter lacteal secretions from cases that occurred prepartum or within 14 d postpartum were examined bacteriologically. The study included 1040 heifers with clinical mastitis, and the total number of quarters that were clinically affected was 1361. The organisms that were most frequently isolated from samples from these quarters were Staphylococcus aureus (44.3%), Streptococcus dysgalactiae (18.2%), Staph. aureus together with Strep. dysgalactiae (1.2%), coagulase-negative staphylococci (12.8%), Arcanobacterium pyogenes (3.5%), A. pyogenes together with Strep. dysgalactiae (0.5%) or Staph. aureus (0.4%), and Escherichia coli (6.4%). Of the coagulase-negative staphylococci, Staphylococcus simulans (53.7%), Staphylococcus hyicus (14.8%), and Staphylococcus chromogenes (14.8%) were the most prevalent species. Except for a higher relative percentage of A. pyogenes in cases that occurred before parturition (8.2%) than in cases that occurred after parturition (2.7%), no significant differences were observed in the distribution of the various organisms among prepartum and postpartum cases. Regional variations were observed in the distribution of organisms. The proportions of Staph. aureus and A. pyogenes were highest, and the proportion of coagulase-negative staphylococci was lowest, in late autumn and early winter. The proportion of E. coli was highest in summer. In heifers in which mastitis was associated with increased rectal temperature or other systemic signs, the proportion of clinically affected quarters that were infected with Staph. aureus was larger than that in heifers without systemic reaction.

Identification of risk factors for clinical mastitis in dairy heifers.

A nested case-control study was conducted to identify risk factors for clinical mastitis in heifers. Cases and controls originated from dairy herds that were enrolled in the Production Recording Scheme. Heifers that had been treated for clinical mastitis prepartum or on the day of parturition were eligible for inclusion as cases. The controls were heifers that had not been treated for clinical mastitis before parturition, during their first lactation, or during the dry period. In the final analysis, 4256 heifers with mastitis and 67,072 control heifers were included. An increase in the incidence of clinical mastitis in the herd, a decrease in the bulk milk somatic cell count, and an increase in the mean milk yield of the herd were associated with an increased risk for clinical mastitis. The risk varied among regions, and, depending on region, significant influences of both herd size and composition of the diet were observed. Heifers kept on pasture in summer were at a decreased risk for clinical mastitis. Calving in late spring or summer was associated with greater risk than was calving at other times of the year. An increase in age at first calving was associated with increased risk of mastitis. Mastitis was also more likely to occur in heifers leaking milk or in heifers that had a low milk flow rate in the subsequent lactation. For purchased heifers, risk factors were identified in both their previous and current herds.

A study of phage- and ribotype patterns of Staphylococcus aureus isolated from bovine mastitis in the Nordic countries.

This study was conducted to investigate the geographical distribution of phage and ribotypes of Staphylococcus aureus causing bovine mastitis in the 5 Nordic countries. A total of 403 isolates of S. aureus was isolated from 403 different dairy herds. One hundred five strains were isolated in Denmark, 81 in Finland, 17 in Iceland, 96 in Norway and 104 in Sweden. The isolates were phage typed and characterized for their EcoRI restriction fragment length polymorphisms of the genes encoding ribosomal RNA (ribotyping). A total of 351 (87%) of the 403 isolates could be typed by phages assigning them to 25 different phage types. Two to 3 different phage types predominated within each country. One type (29/52) accounted for 36% of all the isolates and was found in 4 of the countries. A total of 87 different ribotypes was found among the isolates investigated. As for phage typing 2 to 3 different types predominated within countries. However, except for one type (ribotype 1), which was commonly found in Denmark, Sweden and Finland, different ribotypes predominated within each country. The combination of phage and ribotyping assigned the isolates to 178 different types. Ninety-six percent of the isolates of ribotype 1 belonged to phage type 29/52. This combined type accounted for 17% of all the 403 isolates. These findings show that a large number of different types of S. aureus can be isolated from cases of bovine mastitis. However, few types predominate within different countries. These predominating types seem to be specific in each country, however, a single type was common for both Denmark, Sweden and Finland. This could suggest differences in the virulence or in modes of transmission of predominating and rare types of S. aureus associated with bovine mastitis.

Comparison of two regimens for the treatment of clinical bovine mastitis caused by bacteria sensitive to penicillin.

The efficacies of two regimens for the treatment of acute clinical mastitis were compared in a randomised multi-centre field trial in Norway, using 657 cows. The purpose was to determine whether repeated intramuscular injections of penicillin G for three days were more effective than a single injection, when given in combination with intramammary treatment for five days. The results were evaluated on the basis of clinical and microbiological examinations and cell count determinations of quarter milk samples taken at the initial visit and four weeks later. There were no significant differences between the effects of the treatments, either for all the cows, or for subgroups of the cows based on age, stage of lactation, and systemic reaction, or the type of causal bacteria.

Field studies show associations between pulsator characteristics and udder health.

Four different field studies including 64, 140, 850 and 180 herds were used to investigate the association between pulsator characteristics and udder health. The results indicate that the best udder health is found in herds with a d phase > 330 ms and a pulsation rate > 55 min-1. A d phase of < 250 ms was associated with significant elevation in bulk milk somatic cell count, a higher incidence of acute clinical mastitis and a higher frequency of cows having mastitis associated with major pathogens (mainly Staphylococcus aureus) as compared with a d phase of > 331 ms. There was also a significant positive association between a shorter d phase and a high incidence of teat lesions needing veterinary treatment. Herds having no such teat lesions had pulsators with significantly longer d phase than herds with teat lesions (300 ms v. 288 ms). These results strongly suggest that in high-line milking machines the d phase should not be as short as 250 ms and should preferably be approximately 300 ms, and the pulsation rate should be at least > 55 cycles min-1. There was a strong relationship between the effect of d phase and the rate of pulsation.

Glaucoma screening with oculokinetic perimetry in general practice: is its specificity acceptable?

The main aim of the study was to estimate the specificity of oculokinetic perimetry (OKP) for glaucoma case-finding in general practice. The visual fields of 185 consecutive patients aged 40 years or more were screened with OKP in one general practice. Test specificity was 94%. The OKP test was abnormal in 17 patients. At follow-up 6 of these patients had glaucoma or were glaucoma suspects. Three of the remaining 11 patients had cataract. Eight OKP-positive patients had no eye disease. In 96 of the patients results of OKP were compared with Bjerrum campimetry, which revealed one possibly false-negative OKP test. Ten patients with previously diagnosed glaucoma were also examined with OKP. All 10 patients were identified by the OKP test. In 80 of the patients OKP was performed twice, supervised by two different observers. The proportion of agreement for normal tests was very high: 0.96 (95% CI: 0.91-1.0). The proportion of agreement for abnormal tests was 0.79 (95% CI: 0.57-1.0). The OKP test may be useful in glaucoma case-finding in general practice. However, the proportion of false-positive tests seems to be too high for OKP to be used alone in mass screening.

Free flaps in the reconstruction of foot injury. 4 (1-7) year follow-up of 24 cases.

We reconstructed in 24 patients, traumatic tissue loss in the foot with 10 lateral arm flaps and 14 scapular flaps. The mean follow-up was 4 (1-7) years. There was 1 flap loss, and 1 patient was amputated because of septic ankle arthrodesis. Healing with stable skin and scar was achieved in the remaining patients. Only patients with additional serious skeletal injury had reduced walking ability.