A bitless bridle does not limit or prevent dynamic laryngeal collapse.

BACKGROUND: Bits have often been incriminated as a cause of upper respiratory tract obstruction in horses; however, no scientific studies are available to confirm or refute these allegations. Clinical signs of dynamic laryngeal collapse associated with poll flexion (DLC) are induced when susceptible horses are ridden or driven into the bit. OBJECTIVE: To determine whether use of Dr Cook's™ Bitless Bridle, instead of a conventional snaffle bit bridle, would reduce the severity of DLC in affected horses measured objectively using inspiratory tracheal pressures. STUDY DESIGN: Intervention study using each horse as its own control in a block randomised order. METHODS: Nine Norwegian Swedish Coldblooded trotters previously diagnosed with DLC were exercised on two consecutive days using a standardised high-speed treadmill protocol with either a conventional bridle with a snaffle bit, or Dr Cook's™ Bitless Bridle. Head and neck position, rein tension, inspiratory tracheal pressure measurements, and laryngeal videoendoscopy recordings were obtained. A heart rate greater than 200 bpm, and similar degrees of poll flexion/head height, had to be achieved in both bridles for the individual horse's data to be included for comparison. RESULTS: Seven horses' data met the inclusion criteria. The change in mean inspiratory tracheal pressure between free and flexion phases in the bitless bridle (-15.2 ± 12.3 cmH2 O) was significantly greater (P < .001) than in the snaffle bit bridle (-9.8 ± 7.9 cmH2 O). Mean inspiratory pressure during the free phase was significantly (P < .001) more negative with the snaffle bit bridle (-32.3 ± 6.3 cmH2 O), vs the bitless bridle (-28.5 ± 6.9 cmH2 O). Mean pressures in flexion phase, snaffle bridle (-42.1 ± 10.8 cmH2 O), vs bitless bridle (-43.7 ± 15.6 cmH2 O) where not significantly different between bridles (P = .2). MAIN LIMITATION: Small sample size due to difficulty recruiting suitable clinical cases. CONCLUSIONS: This study could not provide any clear evidence that the effect of a snaffle bit in a horse's mouth influences the development or severity of DLC. Instead, head and neck angles induced by rein tension seem to be the key event in provoking DLC in susceptible horses.

Disease-related and overall survival in dogs with cranial cruciate ligament disease, a historical cohort study.

OBJECTIVE: To analyse the effect of treatment method and other risk factors on survival in dogs with cranial cruciate ligament disease (CCLD). METHODS: A historical cohort study of 333 dogs presenting with CCLD at two University Hospitals (2011-2016) was performed. Signalment, history, treatment and follow-up details were retrieved from medical records, dog owners and referring veterinarians. Treatment groups were defined; conservative or surgical with either lateral fabellotibial suture (LFS) or osteotomy procedures. Multivariable Cox proportional hazards models were applied to evaluate risk factors for disease-related and overall survival. RESULTS: Sixty-five dogs were conservatively managed, 125 treated with LFS and 143 with osteotomy techniques. At follow-up (autumn 2018), 164 dogs (49.3 %) were alive and 169 (50.7 %) were dead. Both final Cox proportional hazards models included variables for treatment, age, weight and hospital. In addition, the final disease-related model included a variable for orthopaedic comorbidity, while non-orthopaedic comorbidities and a time-varying effect for age on a linear scale were included in the overall survival model. Treatment method was found to have an effect on both disease-related and overall survival and surgical treatment was associated with a lower hazard than conservative treatment. CONCLUSION: Survival in dogs with CCLD is influenced by treatment strategy, comorbidities, age and weight.

A comparison of respiratory function in pigs anaesthetised by propofol or alfaxalone in combination with dexmedetomidine and ketamine.

BACKGROUND: General anaesthesia in pigs maintained with intravenous drugs such as propofol may cause respiratory depression. Alfaxalone gives less respiratory depression than propofol in some species. The aim of the investigation was to compare respiratory effects of propofol-ketamine-dexmedetomidine and alfaxalone-ketamine-dexmedetomidine in pigs. Sixteen pigs premedicated with ketamine 15 mg/kg and midazolam 1 mg/kg intramuscularly were anaesthetised with propofol or alfaxalone to allow endotracheal intubation, followed by propofol 8 mg/kg/h or alfaxalone 5 mg/kg/h in combination with ketamine 5 mg/kg/h and dexmedetomidine 4 µg/kg/h given as a continuous infusion for 60 min. The pigs breathed spontaneously with an FIO2 of 0.21. Oxygen saturation (SpO2), end-tidal CO2 concentration (PE'CO2), respiratory rate (fR) and inspired tidal volume (VT) were measured, and statistically compared between treatments. If the SpO2 dropped below 80% or if PE'CO2 increased above 10.0 kPa, the pigs were recorded as failing to complete the study, and time to failure was statistically compared between treatments. RESULTS: Alfaxalone treated pigs had significantly higher respiratory rates and lower PE'CO2 than propofol treated pigs, with a fR being 7.3 /min higher (P = 0.01) and PE'CO2 0.8 kPa lower (P = 0.05). SpO2 decreased by 0.6% and fR by 1.0 /min per kg increase in body weight in both treatment groups. Three of eight propofol treated and two of eight alfaxalone treated pigs failed to complete the study, and times to failure were not significantly different between treatments (P = 0.75). CONCLUSIONS: No major differences in respiratory variables were found when comparing treatments. Respiratory supportive measures must be available when using both protocols.

Prescription Patterns of Non-Vitamin K Oral Anticoagulants Across Indications and Factors Associated with Their Increased Prescribing in Atrial Fibrillation Between 2012-2015: A Study from the Norwegian Prescription Database.

OBJECTIVE: We studied prescription patterns for non-vitamin K oral anticoagulants (NOACs) in Norway between 2012 and 2015, and compared NOAC and warfarin patient characteristics such as age, gender and cardiovascular (CV) co-medications across reimbursed indications. Factors associated with NOAC prescribing in atrial fibrillation (AF) were also analysed. METHODS: All Norwegian patients (N = 156,124) who received at least one dispensed NOAC or warfarin prescription within the indications of AF, deep vein thrombosis and pulmonary embolism (DVT_PE) or prevention of venous thromboembolic events after a hip or knee surgery (VTE_surg) between 2012 and 2015 were included in the study. Descriptive statistics was applied to compare patient characteristics between NOACs and warfarin across indications and a logistic regression model was used to identify factors associated with NOAC prescribing in AF. RESULTS: NOACs and warfarin were most commonly prescribed in AF (83,729 patients in 2015), followed by DVT_PE (16,077 patients) and lastly in VTE_surg (4060 patients). In 2015, NOACs achieved a dominant (>50%) patient share over warfarin in AF and DVT_PE, and were prescribed in >80% of new oral anticoagulation (OAC) patients. Apixaban, despite its delayed market entry, emerged as the preferred NOAC in VTE_surg (46% share), whereas rivaroxaban captured a 43% patient share in DVT_PE. Warfarin patients were on average older and received more CV co-medication than NOAC patients in AF and DVT_PE. Age, gender and certain CV co-medications emerged as significant predictors of NOAC prescribing in AF. AF patients <70 years old had higher odds of NOAC prescribing (OR 1.19-1.29, depending on age category), in contrast to patients >74 years old (OR 0.51-0.77). Women had 32% higher odds of receiving a NOAC in AF. CONCLUSION: NOACs achieved a dominant market share over warfarin within 3 years from receiving reimbursement in Norway. There were significant differences in patient characteristics between drugs and indications.

Major vectors and vector-borne diseases in small ruminants in Ethiopia: A systematic review.

Vector-borne diseases are among major health constraints of small ruminant in Ethiopia. While various studies on single vector-borne diseases or presence of vectors have been conducted, no summarized evidence is available on the occurrence of these diseases and the related vectors. This systematic literature review provides a comprehensive summary on major vectors and vector-borne diseases in small ruminants in Ethiopia. Search for published and unpublished literature was conducted between 8th of January and 25th of June 2015. The search was both manual and electronic. The databases used in electronic search were PubMed, Web of Science, CAB Direct and AJOL. For most of the vector-borne diseases, the summary was limited to narrative synthesis due to lack of sufficient data. Meta-analysis was computed for trypanosomosis and dermatophilosis while meta-regression and sensitivity analysis was done only for trypanososmosis due to lack of sufficient reports on dermatophilosis. Owing emphasis to their vector role, ticks and flies were summarized narratively at genera/species level. In line with inclusion criteria, out of 106 initially identified research reports 43 peer-reviewed articles passed the quality assessment. Data on 7 vector-borne diseases were extracted at species and region level from each source. Accordingly, the pooled prevalence estimate of trypanosomosis was 3.7% with 95% confidence interval (CI) 2.8, 4.9), while that of dermatophilosis was 3.1% (95% CI: 1.6, 6.0). The in-between study variance noted for trypanosomosis was statistically significant (p<0.05). Among the three covariates considered for meta-regression, only one (species) fitted the final model significantly (p<0.05) and explained 65.44% of the between studies variance (R2). The prevalence in sheep (5.5%) increased nearly by 34% compared to goats (2.9%). The parasitic presence in blood was documented for babesiosis (3.7% in goats); and anaplasmosis (3.9% in sheep). Serological evidence was retrieved for bluetongue ranging from 34.1% to 46.67% in sheep, and coxiellosis was 10.4% in goats. There was also molecular evidence on the presence of theileriosis in sheep (93%, n=160) and goats (1.9%, n=265). Regarding vectors of veterinary importance, 14 species of ticks in five genera, four species of Glossina and 4 genera of biting flies were reported. Despite the evidence on presence of various vectors including ticks, flies, mosquitoes and midges, studies on vector-borne diseases in Ethiopia are surprisingly rare, especially considering risks related to climate change, which is likely to affect distribution of vectors. Thus better evidence on the current situation is urgently needed in order to prevent spread and to model future distribution scenarios.

How severe and prevalent are Ebola and Marburg viruses? A systematic review and meta-analysis of the case fatality rates and seroprevalence.

BACKGROUND: Ebola and Marburg virus diseases are said to occur at a low prevalence, but are very severe diseases with high lethalities. The fatality rates reported in different outbreaks ranged from 24-100%. In addition, sero-surveys conducted have shown different seropositivity for both Ebola and Marburg viruses. We aimed to use a meta-analysis approach to estimate the case fatality and seroprevalence rates of these filoviruses, providing vital information for epidemic response and preparedness in countries affected by these diseases. METHODS: Published literature was retrieved through a search of databases. Articles were included if they reported number of deaths, cases, and seropositivity. We further cross-referenced with ministries of health, WHO and CDC databases. The effect size was proportion represented by case fatality rate (CFR) and seroprevalence. Analysis was done using the metaprop command in STATA. RESULTS: The weighted average CFR of Ebola virus disease was estimated to be 65.0% [95% CI (54.0-76.0%), I2 = 97.98%] whereas that of Marburg virus disease was 53.8% (26.5-80.0%, I2 = 88.6%). The overall seroprevalence of Ebola virus was 8.0% (5.0%-11.0%, I2 = 98.7%), whereas that for Marburg virus was 1.2% (0.5-2.0%, I2 = 94.8%). The most severe species of ebolavirus was Zaire ebolavirus while Bundibugyo Ebolavirus was the least severe. CONCLUSIONS: The pooled CFR and seroprevalence for Ebola and Marburg viruses were found to be lower than usually reported, with species differences despite high heterogeneity between studies. Countries with an improved health surveillance and epidemic response have lower CFR, thereby indicating need for improving early detection and epidemic response in filovirus outbreaks.

Serum concentration of gastrin, cortisol and C-reactive protein in a group of Norwegian sled dogs during training and after endurance racing: a prospective cohort study.

BACKGROUND: High incidences of gastritis and gastric ulceration are observed in sled dogs participating in endurance races. Exercise-induced increases in hormones like gastrin and cortisol have been suggested as possible contributing factors. An increase in C-reactive protein (CRP) has also been observed in canines during physical exercise. The aim of this study was to evaluate the effect of long distance racing on the serum concentration of gastrin, cortisol and CRP in a group of sled dogs, by comparing the results achieved early in the training season and after participating in a long distance race; "Femundløpet". Dogs that only trained to the race, but did not compete in the race, were used as control dogs. Sixty-five sled dogs participated in the study; 46 competing dogs (25 completing and 21 non-completing the race) and 19 non-racing dogs (control dogs). The blood samples were collected in October 2012 and February 2013. RESULTS: The post-race serum concentration of gastrin, cortisol and CRP was significantly elevated in sled dogs participating in the race (both completing and non-completing dogs) when compared to the results from training. However, no significant differences were observed between the two sampling dates in the control dogs. Post-race results for completing and non-completing dogs were also compared. This demonstrated a significant elevation in gastrin in non-completing versus completing dogs, and a significant elevation in cortisol in completing compared to non-completing dogs. CONCLUSIONS: Participation in a long distance race was associated with a significant increase in serum gastrin, cortisol and CRP in sled dogs.

Mange mite infestation in small ruminants in Ethiopia: Systematic review and meta-analysis.

Mange mites are economically important ectoparasites of sheep and goats responsible for rejection or downgrading of skins in tanneries or leather industries in Ethiopia. The objective of this systematic review was to compute the pooled prevalence estimate and identify factors influencing mange mite prevalence in sheep and goats at national level based on the available research evidence. Articles on mange mite infestation of small ruminants in Ethiopia were searched in PubMed, Web of Science, Google scholar and African journals on-line. The review was based on 18 cross-sectional studies carried out between 2003 and 2015 in four administrative states of Ethiopia. Accordingly, the pooled prevalence estimate in a random effects meta-analysis was estimated to be 4.4% (95% CI 3.0, 6.3) although there were evidence of a substantial amount of between-study variance (I(2)=98.4%). In subgroup and multivariable meta-regression analyses, animal species, agro-ecology and administrative state were found to have significant effect on the prevalence estimate (P<0.05) and explained 32.87% of the explainable proportion of the heterogeneity noted between studies The prevalence was found to be higher in goats in lowland agro-ecology. Region wise the highest estimate was calculated for Amhara (6.4%) followed by Oromia (4.7%), Tigray (3.6%) and Southern Nations, Nationalities and People Region (SNNPR) (3.1%). Significant difference was noted between Amhara and SNNPR. The study further revealed that mites of the genus Sarcoptes, Demodex and Psoroptes are the most prevalent mites infesting small ruminants in Ethiopia. Valid studies were lacking from five regional states. As some of these regions are known for their large small ruminant population, further studies are warranted to produce better picture of the infestation at a national level. Meanwhile, the need for monitoring the ongoing control intervention is suggested.

The cardiovascular status of isoflurane-anaesthetized horses with and without dexmedetomidine constant rate infusion evaluated at equivalent depths of anaesthesia.

OBJECTIVE: To compare cardiac index and oxygen extraction at equivalent depths of anaesthesia between isoflurane-anaesthetized horses and horses anesthetized with isoflurane and dexmedetomidine CRI. STUDY DESIGN: Sequential, blinded, randomized, balanced, crossover study. ANIMALS: Eight horses weighing a mean ± standard deviation of 478 ± 58 kg. METHODS: Horses were premedicated with 0.03 mg kg(-1) acepromazine intramuscularly (IM) and 8 µg kg(-1) dexmedetomidine intravenously (IV). Anaesthesia was induced with 2.5 mg kg(-1) ketamine and 0.1 mg kg(-1) midazolam IV and maintained with isoflurane in oxygen and air. Horses were mechanically ventilated. Fractional concentration of end-tidal isoflurane (Fe'Iso) was stabilized at 1.7% with a CRI of 0.9% NaCl (IsoNaCl), or at 1.1% with 1.75 µg kg(-1)  hour(-1) dexmedetomidine (IsoDex). Mean arterial blood pressure was maintained above 60 mmHg by dobutamine infusion. Following nociceptive electrical stimulation, Fe'Iso was stabilized at a 0.1% lower concentration and nociceptive stimulation was repeated. This procedure was continued until the horse moved. Fe'Iso values prior to the concentration at which movement occurred were considered to indicate equivalent depths of anaesthesia between treatments. Cardiac index and oxygen extraction were compared at equivalent depths of anaesthesia using a paired Student's t-test. RESULTS: Cardiac index differed between IsoNaCl at 61 ± 12 mL kg(-1)  minute(-1) and IsoDex at 48 ± 10 mL kg(-1)  minute(-1) (p = 0.047). In addition, oxygen extraction differed between IsoNaCl at 3.4 ± 0.8 mL kg(-1)  minute(-1) and IsoDex at 4.5 ± 0.5 mL kg(-1)  minute(-1) (p = 0.0042). Two horses receiving IsoNaCl were administered dobutamine at equivalent depths of anaesthesia (7.0 and 28.8 µg kg(-1)  hour(-1) , respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Cardiovascular function in horses receiving isoflurane and 1.75 µg kg(-1)  minute(-1) dexmedetomidine is more compromised than in horses receiving a higher concentration of isoflurane and 0.9% NaCl CRI.

Toxoplasma gondii seroprevalence in pet cats in Norway and risk factors for seropositivity.

OBJECTIVES: The aims of the study were to estimate Toxoplasma gondii seroprevalence in pet cats in Norway and to evaluate risk factors for seropositivity. Additionally, serum biochemistry and haematological variables for T gondii seropositive and seronegative cats were compared. METHODS: A convenience sample of surplus sera submitted to the Central Laboratory, Norwegian University of Life Sciences, was collected. The samples were from healthy cats and cats with a variety of diseases. Analyses for IgG antibodies to T gondii were performed with a commercial direct agglutination test, with 1:40 as the threshold value. For risk factor analysis a logistic regression model of the relationship between predictors and the outcome was applied. RESULTS: One hundred and ninety-six of 478 cats were seropositive for T gondii, and the estimated seroprevalence in the study sample was 41.0% (95% confidence interval 36.6-45.4). Compared with domestic cats, pedigree cats had reduced risk for Toxoplasma seropositivity (odds ratio [OR] 0.42). Males had increased risk (OR 1.63) compared with females. The effect of age was highly significant, and an increase in the cats' age across the interquartile range (IQR; 52-160 months/4-13 years of age) doubled the risk of Toxoplasma seropositivity (OR 2.11). The risk for Toxoplasma seropositivity among cats living in Oslo was significantly reduced (OR 0.51) when compared with the rest of Norway. CONCLUSIONS AND RELEVANCE: Pet cats in Norway appear to be commonly exposed to T gondii. Signalment and geographical region influenced the odds of Toxoplasma seropositivity, whereas health status did not.

Meta-analysis of Brucella seroprevalence in dairy cattle of Ethiopia.

This meta-analysis estimates a single-group summary (effect size) for seroprevalence of Brucella spp. exposure in dairy cattle of Ethiopia. It also attempts to identify study-level variables that could explain the variation in apparent seroprevalence. The literature search was restricted to studies published in English language from January 2000 to December 2013. A template was designed to retrieve the most biologically plausible and consistent variables from the articles. A total of 29 published papers containing 40 animal-level studies were used in the analyses. The single-group summary of Brucella seroprevalence in cattle was estimated to reach 3.3 % with 95 % confidence interval (CI) (2.6-4.2 %). Of all the variables considered, region was the only specific factor identified to explain about 20 % of between-study variation. Accordingly, the region-based meta-analysis forest plot revealed the highest prevalence in central Ethiopia followed by southern part. The lowest prevalence estimate was observed in the western part of the country. The visual inspection of the funnel plot demonstrated the presence of possible publication bias which might dictate shortage of studies with higher prevalences or variance inflation due to infectiousness of Brucella. In conclusion, the quantitative review showed the seroprevalence to be low but widely distributed. More importantly, the review underscores the need for isolation and characterization of the circulating Brucella spp. to capture the type of Brucella spp. involved and its distribution in cattle in Ethiopia.

Surgical treatment of equine colic - a retrospective study of 297 surgeries in Norway 2005-2011.

BACKGROUND: Colic, defined as pain originating from the abdomen, is a common condition in horses. Most of the cases resolve spontaneously or after medical treatment, but a few require surgical treatment. Surgical treatment of colic in horses is resource-demanding and expensive, and information on prognosis is therefore important for both owners and surgeons. In the present study, surgical cases in two equine hospitals in Norway between 2005 and 2011 were reviewed. The aim of the study was to describe associations between prognostic indicators, diagnoses and short term survival by use of random effects logistic regression. RESULTS: In the present study, 162 out of 297 (54.5%) surgeries resulted in the horse being discharged from the hospital. Excluding cases euthanized during surgery, the overall short-term survival was 74.0% (162 out of 219 surgeries). Seventy-eight (26.3%) of the horses were euthanized during surgery, due to grave or poor prognosis. In univariable analyses, duration of colic signs, heart rate, capillary refill time, mucosal membrane appearance, intestinal sounds, affected gastrointestinal segment, hematocrit, intestinal resection, hospital and surgeon board-certification had P-value <0.20 and were assessed in multivariable analyses. Respiration rate, rectal temperature and lactate in blood also had univariable P <0.20, but were left out from multivariable analyses due to too high levels of missing values. A random effect of primary surgeon was included and breed, sex and age were tested in multivariable analyses as possible confounders; and hospital was included to control for hospital routine differences. In the final multivariable model the variables mucosal membrane appearance, affected gastrointestinal segment and surgeon board-certification significantly influenced survival. The random surgeon effect was not significant. CONCLUSIONS: The present study showed that prognostic parameters and diagnoses of surgical treatment of horses with colic in Norway are in accordance with reports from other parts of the world. The significant effect of board-certification of surgeon is not reported in previous studies. The general short-term survival rate was somewhat lower than reported in other studies, partly due to more horses being euthanized intraoperatively in the present study. This might be because of economical or animal welfare reasons.

Evaluation of urinalyses from untreated adult cats with lower urinary tract disease and healthy control cats: predictive abilities and clinical relevance.

This case-controlled study evaluated urinalyses from 111 primary cases diagnosed with feline lower urinary tract disease (FLUTD) and 101 healthy control cats. Urine samples were analysed by standardised procedures, and differences between the two groups were compared by multivariable logistic regression analysis, while controlling for age, body weight, gender and reproductive status. Further, the ability of using urine sediment findings to predict bacteriuria was evaluated. In addition, urinalyses from cats with bacterial cystitis, idiopathic cystitis, urolithiasis and urethral plugs were compared. The main findings were that increasing body weight was significantly associated with increased odds of FLUTD, while the influence of age and reproductive status was of less importance. Increasing amounts of red blood cells and epithelial cells were significantly associated with increased odds of FLUTD. The predictive ability of using bacterial sediment findings to predict bacterial growth was dependent on subjective grading of the amount of bacteria in the sediment and was, at best, only moderate. The few significant differences found between the different FLUTD diagnoses were of limited diagnostic value.

Housing- and exercise-related risk factors associated with the development of hip dysplasia as determined by radiographic evaluation in a prospective cohort of Newfoundlands, Labrador Retrievers, Leonbergers, and Irish Wolfhounds in Norway.

OBJECTIVE: To identify housing- and exercise-related risk factors associated with the development of hip dysplasia (HD) as determined by radiographic evaluation in Newfoundlands, Labrador Retrievers, Leonbergers, and Irish Wolfhounds in Norway. ANIMALS: 501 client-owned dogs from 103 litters. PROCEDURES: Dogs were assessed from birth until official radiographic screening for HD at 12 (Labrador Retriever [n = 133] and Irish Wolfhound [63]) or 18 (Newfoundland [125] and Leonberger [180]) months of age. Information regarding housing and exercise conditions during the preweaning and postweaning periods was obtained with questionnaires. Multivariable random effects logistic regression models were used to identify housing- and exercise-related risk factors associated with the development of radiographically detectable HD. RESULTS: Puppies walking on stairs from birth to 3 months of age had an increased risk of developing HD. Factors associated with a decreased risk of developing HD included off-leash exercise from birth to 3 months of age, birth during the spring and summer, and birth on a farm. Significant clustering of dogs with HD was detected within litters. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that puppies ≤ 3 months old should not be allowed access to stairs, but should be allowed outdoor exercise on soft ground in moderately rough terrain to decrease the risk for developing radiographically detectable HD. These findings could be used as practical recommendations for the prevention of HD in Newfoundlands, Labrador Retrievers, Leonbergers, and Irish Wolfhounds.

Risk factors for hip-related clinical signs in a prospective cohort study of four large dog breeds in Norway.

We conducted a prospective cohort study including privately owned dogs from the breeds Newfondland (NF), Labrador Retriever (LR), Leonberger (LEO), and Irish Wolfhound (IW) followed from birth until age 9 yrs. We wanted to investigate whether radiological hip dysplasia status given at approximately age 12-18 mos and other factors during growth influenced development of clinical signs due to hip-joint disease necessitating veterinary consultation. Whether or not such signs occurred due to hip dysplasia or due to secondary or primary DJD could not be distinguished, and we therefore used the term "owner-reported veterinary-diagnosed hip-related clinical signs" ("the event"). The included dogs were followed from birth to the event or until a maximum of 9 yrs of age. Our objectives were to describe breed differences in time to incidence and to evaluate potential risk factors for the time to event. We used Kaplan-Meier curves to describe time to incidence, and potential risk factors were assessed by use of a Cox proportional-hazards model. We enrolled 494 dogs from 103 litters, and 46 dogs were reported as having had the event during the observation period. We observed a significant time-varying effect (TVE): LR and LEO developed clinical signs later in life than NF. If the radiological hip status was either mild, moderate, or severe the hazard of experiencing the event was significantly increased. Access to off-leash exercise at age 12 mos decreased the hazard of the event, and the hazard varied by litter. The findings supported the hypothesis that radiological hip status at screening and exercise conditions during growth influenced the time to incidence of the event and that there were breed differences in time to the event.

The effect of radiological hip dysplasia and breed on survival in a prospective cohort study of four large dog breeds followed over a 10 year period.

The aim of the study was to measure the effect of radiological hip and elbow dysplasia status and breed on overall survival in a cohort of four large dog breeds in Norway. Privately owned dogs of the Newfoundland (NF), Labrador Retriever (LR), Leonberger (LEO), and Irish Wolfhound (IW) breeds were followed prospectively from birth to 10 years of age. The age of death/euthanasia was registered. A total of 501 dogs from 103 litters were enrolled. Kaplan-Meier survival curves were used to describe breed differences in survival times. The effects of radiological hip and elbow dysplasia status as well as breed were assessed using a Cox proportional hazards model. The variables 'sex' and 'living region' were explored as potential confounders. Among LRs, 60.2% of the dogs were still alive at 10 years of age, and the corresponding figures for NFs, LEOs, and IWs were 28.8%, 16.11%, and 6.4%, respectively. Radiological hip dysplasia status and breed were found to influence overall survival. Two different time-varying effects were observed in that with the IW the hazard of death increased linearly through time, while the effect of severe radiological hip dysplasia decreased logarithmically with time. Location influenced the death hazard and dogs living in suburban areas or cities had longer mean time to death and a lower hazard compared to dogs living in the countryside. Radiological elbow dysplasia status was not found to have an effect on overall survival.

A prospective study on canine hip dysplasia and growth in a cohort of four large breeds in Norway (1998-2001).

The study-objective was to measure the effect of weight and growth related parameters on the risk of development of Canine Hip Dysplasia (CHD). The hypothesis was that heavy and fast growing dogs of large sized breeds were at increased risk of development of CHD compared to lighter and slower growing dogs. A prospective cohort study was conducted among dogs of four large breeds: Newfoundland (NF), Leonberger (LEO), Labrador retriever (LR), and Irish wolfhound (IW). The dogs were privately owned with individualized nutrition and environment, and they were followed from birth and throughout the growth period until the official screening for CHD was performed. The study sample consisted of 501 dogs from 103 litters, with the breed distribution 125 NF, 180 LEO, 133 LR, and 63 IW. Because the dogs were clustered in litters a multivariable random effects logistic regression model was used to assess statistically significant growth-related risk factors for CHD. The estimated incidence risk of CHD was 36% in NF, 25% in LEO, 20% in LR, and 10% in IW. Based upon the final multilevel model it appears that the odds of CHD among both LR and IW (odds ratio (OR) 0.22) are about one-fifth of the odds for NF. The odds for LEO (OR 0.60) are not significantly different from NF. There appeared to be an inverse relationship between body weight at 3 months of age and odds of CHD, with an OR of 0.89 (P=0.044). The degree of clustering at the litter-level was high (22.6%) and highly significant (P<0.001). Findings failed to support the hypothesis that heavy and fast growing dogs from four large sized breeds were at increased risk for development of CHD. There might be other unmeasured environmental risk factors for CHD in this cohort of dogs, although the contribution of the genetic variance to the litter-level clustering also needs further investigation.

Bacteriuria in cats with feline lower urinary tract disease: a clinical study of 134 cases in Norway.

Feline lower urinary tract disease (FLUTD) is considered to be one of the most common diagnoses in feline patients. Several authors have concluded that feline idiopathic cystitis is the most common cause of FLUTD, whereas infectious cystitis is diagnosed in only 2% of the cases. In the period from January 2003 to February 2005, 134 cats that presented with signs of lower urinary tract disorders were included in a study at the Norwegian School of Veterinary Science. Ninety-seven percent were first opinion cases. All the cats went through a physical examination, and blood samples were collected for haematology and clinical chemistry. The urine analysis included urine stix, specific gravity, microscopic examination of the sediment and microbiological culturing. The urine samples were collected as voided mid-stream urine samples, by catheter or by cystocentesis and the method used was registered. Of the 134 cats included in the study, 37% were diagnosed as having obstructive and 63% as having non-obstructive FLUTD. In total 44 cats (33%) were diagnosed with bacteriuria, exceeding 10(3) colony forming units per millilitre (cfu/ml) and 33 (25%) of these cats had bacterial growth exceeding 10(4) cfu/ml, either alone or in combination with crystals and/or uroliths. Six cats (18%) with bacterial growth exceeding 10(4) cfu/ml were older than 8 years. No significant difference was found between the sampling methods performed with regard to bacteriuria. This study indicates that bacteriuria may have been underdiagnosed in Norwegian cats with clinical signs of FLUTD. It also confirms the importance of microbiological culturing in first opinion cases with FLUTD and that a skilled operator can get representative samples regardless the choice of method.