Two-dimensional, M-mode and left atrial velocity echocardiographic measurements in healthy Norwegian-Swedish Coldblooded Trotters.

INTRODUCTION: The Norwegian-Swedish Coldblooded Trotter (NSCT) is an important breed in Norwegian and Swedish harness racing. In spite of this, little is known about its cardiac measurements and factors that may influence these. The aims of this study were to establish reference intervals (RI) for a series of conventional echocardiographic variables, primarily of the left heart, in NSCTs in race training and to evaluate any effects age, gender, estimated body weight (EBW), number of starts and racing performance may have on these. ANIMALS: Sixty-three apparently healthy NSCTs in race training. METHODS: Observational study, convenience sampling. All horses were examined unsedated in their normal stabling environment. Auscultatory and echocardiographic examinations were performed. Means, standard deviations, medians and confidence intervals of the RI limits were used to summarize the data. The relationship between selected echocardiographic variables and age, gender, EBW, racing performance and number of starts were explored using linear regression analyses. RESULTS: Reference intervals were determined for routinely used echocardiographic variables. Data for left atrial velocity were also obtained. Increasing age, number of starts and money earned significantly increased all cardiac measurements. Males had significantly higher ventricular measurements than females. Great vessel measurements increased with increasing EBW. Horses with faster recorded racing times had generally significantly increased cardiac measurements. Clinically insignificant valvular regurgitation was a common finding, particularly at the tricuspid and pulmonary valves. CONCLUSIONS: The RIs described and the factors that may affect these will assist clinicians in interpreting echocardiograms of NSCTs with suspected cardiac disease or poor performance.

Acquired equine polyneuropathy of Nordic horses: A conspicuous inclusion body schwannopathy.

Acquired equine polyneuropathy (AEP), formerly also known as Scandinavian knuckling syndrome, is one of the most prevalent polyneuropathies in equids in Norway and Sweden, with more than 400 cases registered since first observations in 1995. Despite geographical clustering and an association to forage feeding, its aetiology remains unknown. Clinically AEP is characterized by knuckling due to dysfunction of metatarsophalangeal extensor muscles. This neuropathological study aimed to gain further insights in the pathobiology of AEP and its underlying aetiopathogenesis. We thereby confirmed that all affected horses suffered from similar large fibre neuropathy, exhibiting conspicuous Schwann cell inclusions in most samples, suggestive of a primary disruption of Schwann cell metabolism leading to inclusion body schwannopathy with secondary inflammatory changes. The degree of nerve pathology was not predictive of clinical outcome.

Long-term follow-up of Norwegian horses affected with acquired equine polyneuropathy.

BACKGROUND: Acquired equine polyneuropathy (AEP), a neurological disease clinically characterised by knuckling of metatarsophalangeal joints, has been described in numerous Nordic horses during the last 20 years. Although clinical recovery has been reported, large-scale data on long-term follow-up of survivors have been lacking. OBJECTIVES: To describe long-term survival of AEP affected horses registered in Norway, with a focus on athletic performance and possible residual clinical signs connected to the disease. STUDY DESIGN: A retrospective cohort study. METHODS: The study includes 143 horses recorded with AEP in Norway from 2000 to 2012, with the follow-up period continuing until 2015. Participating owners of survivors completed a standardised questionnaire, providing information on disease and convalescence, management, performance-level and possible residual clinical signs. To investigate the follow-up of survivors, we performed 2 multivariable linear regression models. RESULTS: The follow-up time of survivors was 1.0-14.5 years (median 5.3, interquartile range 2.5-7.2). Fifty-seven horses survived and all but 3 horses returned to previous or higher level of performance. However, possible disease-related residual clinical signs were reported in 14/57 horses. Forty-nine of the survivors were in athletic use at time of contact. The majority of survivors were categorised with low severity-grades at time of diagnosis and the initial grade was significantly associated with time to resumed training. Only 3 horses had experienced relapse/new attack during the follow-up period. MAIN LIMITATION: Athletic performance was judged by owners, which renders a possible source of bias. CONCLUSIONS: Although AEP is a potential fatal disease, most survivors will recover and return to minimum previous level of athletic performance. Some horses display residual clinical signs, but often without negative effect on performance and relapse of disease is rare.

Acquired equine polyneuropathy in Norway and Sweden: a clinical and epidemiological study.

REASONS FOR PERFORMING STUDY: Acquired equine polyneuropathy (AEP, also known as 'Scandinavian knuckling syndrome'), is a serious disease of unknown aetiology, which emerged clustering in horse farms in Sweden, Norway and Finland in the 1990s. Clinical and epidemiological data regarding the syndrome are scarce. OBJECTIVES: To describe the clinical and epidemiological findings and outcome in outbreaks of AEP and compare risk factors in affected and unaffected horses on affected farms in Norway and Sweden during 2007-2009. METHODS: Neurological examinations were performed and data collected regarding demography, usage, turning-out, feeding, prophylactic strategies and long-term outcome. RESULTS: Thirteen affected farms with 157 horses of various breeds, of which 42 were AEP cases, were studied. Typical digital extensor dysfunction and knuckling of pelvic limbs were noted in 34 definitive cases. Eight additional plausible cases had a severe, acute course of neurological disease. There were no signs of brain orcranial nerve dysfunction. Cases occurred from December to April, with new cases emerging within 100 days of the index case. Affected and unaffected horses were fed wrapped forage. Prevalence for AEP was 27% and case fatality 29%. The median duration of AEP in survivors was 4.4 months (1-17 months). Survivors returned to full work within 19 months (median 6.6 months). Acquired equine polyneuropathy was less prevalent in horses aged > 12 years and young horses had a higher chance of survival than older horses. Management factors did not differ between affected and unaffected horses. CONCLUSIONS: Acquired equine polyneuropathy is a potentially fatal neurological disease characterised by pelvic limb knuckling. Surviving horses returned to normal function after a long period of rest. Cases were clustered in farms during the winter/spring season. Wrapped forage was used in all farms. POTENTIAL RELEVANCE: The results provide valuable insights into the dinical examination, handling and prognosis of cases of AEP, an emerging neurological disease of unknown aetiology in horses.

Relative prevalence of upper respiratory tract obstructive disorders in two breeds of harness racehorses (185 cases: 1998-2006).

REASONS FOR PERFORMING STUDY: Two genetically and phenotypically distinct horse breeds are used for harness racing in Scandinavia: the Standardbred (SB) and Coldblooded Trotter. These racehorses have identical environmental, management and racing conditions. Therefore, this study was undertaken to identify and compare the relative prevalence of upper respiratory tract (URT) obstructive disorders in these 2 breeds. OBJECTIVES: To determine whether these 2 phenotypically different breeds of harness racehorses have different predispositions for URT disorders. METHODS: Retrospective study of 88 Norwegian Coldblooded Trotters (NCT) and 97 SBs referred to this hospital for URT evaluation between 1998 and 2006. Case records of all horses diagnosed with an URT disorder during resting endoscopy, and all horses undergoing high-speed treadmill videoendoscopy (HSTV) with one or more periods of induced poll flexion were evaluated. The relative prevalence of URT disorders between the 2 breeds was analysed using a Fisher's exact test. RESULTS: There was a significant (P<0.05) breed predisposition regarding 6 URT disorders. Bilateral dynamic laryngeal collapse associated with poll flexion and flaccid epiglottis was significantly more frequent in the NCT. Alar fold collapse and nasopharyngeal collapse were significantly more frequent in SBs. Epiglottic entrapment and nasal flutter were only diagnosed in the SBs. Dynamic disorders were more common than resting disorders in both breeds. CONCLUSION: URT obstructive disorders (dynamic laryngeal collapse associated with poll flexion, flaccid epiglottis, pharyngeal collapse, alar fold collapse, nasal flutter and epiglottic entrapment) are breed related, indicating an anatomic or functional cause. Periods of induced poll flexion during HSTV was essential to declare harness racehorses free of URT disorders. POTENTIAL RELEVANCE: Further anatomic or physiological studies comparing these breeds could potentially provide insight into the pathogenesis of certain URT obstructive disorders. Induced poll flexion should be included in routine HSTV examinations of all harness racehorses.

Polyneuropathy associated with forage sources in Norwegian horses.

BACKGROUND: Cases of hindlimb digital extensor weakness of unknown etiology have been observed in Norway since 1995. HYPOTHESIS: We hypothesized that the observed bilateral extensor weakness was attributable to neuropathy of the distal nerves and that this was related to environmental factors, possibly dietary. ANIMALS: Seventy-five horses with digital extensor weakness occurring from 1995 to 2004 are described. METHODS: Eleven horses were examined at The Norwegian School of Veterinary Science, and the medical records of 64 horses seen in ambulatory practice were reviewed. RESULTS: There was no apparent sex, age, or breed predilection, but the majority were horses kept for pleasure or breeding purposes. Clinical signs varied from intermittent knuckling of the hindlimbs to paraplegia. Some horses showed no or only slow progression of signs, whereas others developed severe signs within hours. No other neurologic deficits were detected in any of the horses. Epidemiologic data and laboratory results were not supportive of an infectious etiology. The only common factor for all affected horses seemed to be feeding big bale silage or, occasionally, hay of poor microbiologic quality. Forty of the 75 horses were euthanized. Histopathologic examination of peripheral nervous tissue was performed in 22 horses, all of which had neuronal fiber degeneration. The majority of horses with mild signs recovered after 5-6 months of rest. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinical signs correlated with polyneuropathy involving sciatic nerves.

Patient performance with two types of multiple electrode intracochlear implant.

The functional results of 9 persons implanted with the Symbion Ineraid and 8 persons implanted with the Nucleus cochlear implant with the F0, F1, F2 coding strategy are reported. All patients were postlingually totally deaf, the patients implanted with the Symbion Ineraid were all above 40 years of age, while the Nucleus patients were with one exception under 40 years of age. The CID Everyday Sentences Test, the Helen Test and the Speech Tracking Test showed that all patients improved their communication skills when sound through the implant was added to lip-reading. The patients' ability to understand without lip-reading was tested with the CID everyday sentences test, with the Helen test, with spondees, with three-choice vowels and with a consonant confusion test. These showed that all 9 Symbion Ineraid patients achieved some degree of open speech understanding. Four of the 8 Nucleus patients achieved some degree of open speech understanding. Difference limen tests for intensity and frequency indicated that 2 of the Nucleus patients who did not achieve open speech understanding probably had extensive cochlear nerve damage, while the remaining 2 Nucleus patients without open speech understanding had good frequency and intensity discrimination.

[Care of hearing in the elderly in Akershus. Use of hearing aids]. / Hørselomsorg blant eldre i Akershus. Bruksfrekvens av høreapparat.

The daily use of hearing aids was investigated in two groups of persons over 70 years of age. One group received only initial instruction in the use of the hearing aid. In this group only six of the 35 patients used their hearing aid every day or on most days. In the other group, which received a further audiopedagogical follow-up, the corresponding figure was 48 out of 61. Better cooperation between the primary health care and ear-nose-and throat-departments/specialists may lead to a better audiopedagogical follow-up of these patients.

[Care of hearing in the elderly in Akershus. Needs and provisions]. / Hørselomsorg for eldre i Akershus. Behov og behovsdekning.

543 persons over 70 years of age and living in Akershus county near Oslo were offered a hearing test at the local health centre. 495 (91%) were tested. The test revealed that 111 (22.4%) needed a hearing aid. 52 (10.5%) of these already had a hearing aid. Most of those who required a hearing aid (97.3%) belonged to the group with subjective hearing problems. It is concluded that good health care for the elderly also includes a hearing test for persons with a hearing problem, and provision of a hearing aid if necessary. It is important that also this part of the health care is provided locally.