Demographics and costs of colic in Swedish horses.

BACKGROUND: Colic is an important cause of morbidity and mortality in horses. In Sweden, an insurance database with diagnostic medical information is maintained on >30% of the nation's horse population. HYPOTHESIS: The objective was to describe the occurrence of colic, defined by costly veterinary care and life claims, in horses at 1 insurance company during 1997-2002. HORSES: All horses (<21 years of age) with complete insurance for veterinary care and life during the period 1997-2002 were included. METHODS: Colic was defined as conditions where the main clinical sign was abdominal pain and the problem was related to the gastrointestinal system. The analyses included measures of incidence by sex, breed group, age categories, geographical location (urban/other), survival to and survival after colic, medical cost for colic, and multivariable modeling of risk factors related to the event of colic. RESULTS: In all, 116,288 horses contributed to 341,564 horse years at risk (HYAR). There were 3,100 horses with a colic diagnosis, of which 27% were settled for life insurance. The median gross cost for veterinary care was 4,729 Swedish Kronor (SEK). The overall occurrence and mortality rate of colic was 91 and 24 events per 10,000 HYAR. Survival after colic at 1 month was 76% (95% confidence interval: 75-78%). CONCLUSIONS AND CLINICAL IMPORTANCE: The occurrence of colic varied with breed group, age, and season. The mortality rates probably reflected the true mortality of colic. The veterinary care rates most likely underestimated of the risk colic because they represent relatively costly events.

Assessment of maximal aerobic power and critical power in a single 90-s isokinetic all-out cycling test.

The purpose of this study was to establish the validity of a 90-s all-out test for the estimation of maximal oxygen uptake (V.O (2max)) and submaximal aerobic ability as represented by critical power. We hypothesized that the fall in power output by the end of the 90-s all-out test (end power) would represent the exhaustion of anaerobic work capability, and as such, would correspond with the critical power. Sixteen active individuals (mean +/- SD: 30 +/- 6 years; 69.6 +/- 9.9 kg) carried out a series of tests: (i) an incremental ramp test to determine V.O (2max), (ii) three fixed-work rate trials to exhaustion to determine critical power, and (iii) two 90-s all-out tests to measure end power and peak V.O (2). End power (292 +/- 65 W) was related to (r=0.89) but was significantly higher (p<0.01) than critical power (264 +/- 50 W). The mean +/- 95 % limits of agreement (29 +/- 65 W) were too low to use these variables interchangeably. The peak V.O (2) in the 90-s trial was significantly lower than the V.O (2max) (3435 +/- 682 ml x min (-1) vs. 3929 +/- 784 ml x min (-1); p<0.01); mean +/- 95 % limits of agreement was equal to 495 +/- 440 mL x min (-1). The 90-s all-out test cannot, therefore, assess both V.O (2max) and critical power in adult performers. The duration of all-out exercise required to allow V.O (2) to attain its maximum is longer than 90 s.

Mortality of Swedish horses with complete life insurance between 1997 and 2000: variations with sex, age, breed and diagnosis.

The aim of this study was to evaluate the potential usefulness of the database maintained by the Swedish insurance company Agria for providing mortality statistics on Swedish horses. Mortality statistics (incidence rates and survival) were calculated, both crudely and stratified by sex, age, breed, breed group and diagnosis, for the horses with complete life insurance, which covers most health problems. The total mortality was 415 (95 per cent confidence interval [CI] 399 to 432) deaths per 10,000 horse-years at risk, and the diagnostic mortality, including only deaths with an assigned diagnosis, was 370 (95 per cent CI 355 to 386) deaths per 10,000 horse-years at risk. The diagnostic mortality of geldings was 459 (95 per cent CI 431 to 487), of mares 345 (95 per cent CI 322 to 365) and of stallions 214 (95 per cent CI 182 to 247) deaths per 10,000 horse-years at risk. The mortality rates increased with age and differed widely between breeds. Survival analysis showed that the median age at death of the horses enrolled before they were one year of age was 18.8 years. The most common cause of death or euthanasia was joint problems, which were responsible for 140 (95 per cent CI 130 to 149) deaths per 10,000 horse-years at risk. The results of multivariable models developed by using Poisson regression generally agreed well with the crude results.

Specific causes of morbidity among Swedish horses insured for veterinary care between 1997 and 2000.

The principal aim of this study was to analyse the incidence of disease due to general and more specific causes among over 100,000 horses covered by complete insurance for veterinary care by a Swedish insurance company during 1997 to 2000. The database was used to calculate the rate of cause-specific morbidity in horses of different ages, sexes and breed groups kept in different regions with different human population densities. The joints were the most commonly affected part of the body, followed by unspecified/whole body, the skin and the digestive system. The most common specific diagnosis was fetlock arthritis, followed by lameness of undefined origin, other locomotor problems, traumatic injuries to the skin, arthritis in several joints, and colic. Geldings had the highest rate of at least one disease event in the joints, unspecified/whole body, skeletal or respiratory system, whereas in the other four major systems the difference between the sexes was marginal.

Morbidity of Swedish horses insured for veterinary care between 1997 and 2000: variations with age, sex, breed and location.

The aim of this study was to evaluate the potential usefulness of the database maintained by the Swedish insurance company Agria for providing disease statistics on Swedish horses. The demography of the horses insured for veterinary care during the period 1997 to 2000 was recorded and the incidence of morbidity, defined as horses that required veterinary care that cost more than the policy excess, was calculated. Yearly incidences were calculated for horses that required veterinary care at least once, first overall, and then for horses with complete insurance, by sex, age, breed group, breed, location and human population density. Poisson regression was applied to a multivariable model to produce estimates of relative risk adjusted for other factors in the model, such as age. The total number of horse-years at risk for those with complete insurance was over 72,000 each year. The annual incidence rate for horses that required veterinary care at least once varied from 1080 to 1190 events per 10,000 horse-years at risk; for geldings the averaged incidence rate was 1398 events, for mares it was 1042 events, and for stallions it was 780 events per 10,000 horse-years at risk. There were considerable variations in incidence rate between breeds.

Correlates of mental health service utilization and unmet need among a sample of male adolescents.

The authors sought to identify the correlates of mental health services utilization and unmet need for these services among a sample of adolescent males. We hypothesized that our findings would replicate and extend those of the recent Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) study, which found that parental factors play a major role in their children's unmet mental health care needs. Our study involved an evaluation of mental health service utilization and unmet need during the prior 2 years, as reported by the subjects at a follow-up assessment at age 16. Four factors were found to predict increased mental health services utilization, including attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) among the adolescent males, the father's alcohol use disorder, and the mother's amphetamine use disorder. One factor was found to predict decreased utilization, the father's cannabis use disorder. Four factors significantly predicted unmet treatment need, including conduct disorder, the mother's amphetamine use disorder, a higher number of siblings, and a parental history of having had a childhood anxiety disorder. The results of this study suggest that parental psychopathology, parental substance abuse, the presence of conduct disorder, and an increased number of siblings act as barriers to adequate mental health treatment among adolescents. These findings confirm the crucial role that parental factors play in the treatment utilization and the unmet treatment need of their children, and also suggest that an increased number of siblings can also be associated with unmet treatment need.

Assessment of muscle oxygenation in the horse by near infrared spectroscopy.

This study examined the ability of near infrared spectroscopy (NIRS) to noninvasively determine changes to muscle oxygenation in the resting horse. Five horses had (NIRS) performed over extremity muscle while under general anaesthesia, first with 8 min limb ischaemia, then systemic hypoxaemia for 5 min. A second group of 6 awake horses had NIRS performed over extremity muscle while being administered hypoxic gas (F(I)O2 0.10) for 5 min, and after return to steady state, limb ischaemia was induced for an additional 5 min. In the anaesthetised horses' ischaemia induced marked and significant muscle deoxygenation of haemoglobin/myoglobin (P<0.01), with corresponding arterial saturation decreasing from 98.9 to 81.9%. Hypoxaemia induced small yet significant muscle deoxygenation (P<0.01) that was 3.2% of the ischaemia deoxygenation signal, with a corresponding decrease in arterial saturation from 98.6 to 90.4%. In the awake horses muscle deoxygenation was not detectable during hypoxia despite reduction of arterial saturation from 97.8 to 86.8%, whereas ischaemia induced rapid and significant deoxygenation of muscle (P<0.05), with corresponding reduction of venous saturation from 78.4 to 75.4%. In neither group of horses was there evidence of cytochrome aa3 reduction, despite complete ischaemia for up to 8 min. NIRS changes in the resting horse muscle clearly differed between ischaemia and hypoxaemia, and can readily show muscle deoxygenation in clinically relevant hypoxaemia in the horse under anaesthesia. Further, as the deoxygenation signal induced by ischaemia was clearly detectable above a background movement artefact, NIRS application to study of muscle oxygenation in the working horse should be explored.

Near infrared spectroscopy for non-invasive assessment of intracranial haemoglobin oxygenation in an in vitro model of the calf head.

An in vitro model of the calf head was used to examine the ability of near infrared spectroscopy (NIRS) to non-invasively determine oxygenation events within the calf head. The brains were removed from 16 calf skulls and replaced with oxygenated dilutions of calf blood that had the oxygen progressively decreased from PO2 > 110 mmHg to < 10 mmHg. Appropriate placement of the lighting source and sensor (optodes) was examined, as were the influences of skull thickness and overlying skin of the skull (including colour). The changes in haemaglobin oxygenation in the model calf head, as observed by NIRS, were highly correlated to PO2 changes in all 16 calf skulls examined (mean r2=0.91, range 0.71 to 0.99). There was a trend for optode positioning to achieve optimal NIRS signals over the middle of the frontal bone in a longitudinal axis and with optodes spaced 4 cm apart, but with the large variation between calf heads this was not shown to be significantly different from other sites tested. The presence of skin over the skull had a significant damping effect on the NIRS signal when compared with the bare skull (P<0.01) but it was not possible to detect a difference in this damping effect between black and white coloured skin. All but the two thickest skulls (13 and 14 mm frontal bone thickness) appeared to allow sufficiently strong NIRS signals of changes in haemoglobin oxygenation. This study showed that NIRS can be used for non-invasive study of oxygenation events within the cranial cavity of calves, and established some guidelines and limitations for its use in this species.

Additional modules for versatile and economical PCR-based gene deletion and modification in Saccharomyces cerevisiae.

An important recent advance in the functional analysis of Saccharomyces cerevisiae genes is the development of the one-step PCR-mediated technique for deletion and modification of chromosomal genes. This method allows very rapid gene manipulations without requiring plasmid clones of the gene of interest. We describe here a new set of plasmids that serve as templates for the PCR synthesis of fragments that allow a variety of gene modifications. Using as selectable marker the S. cerevisiae TRP1 gene or modules containing the heterologous Schizosaccharomyces pombe his5+ or Escherichia coli kan(r) gene, these plasmids allow gene deletion, gene overexpression (using the regulatable GAL1 promoter), C- or N-terminal protein tagging [with GFP(S65T), GST, or the 3HA or 13Myc epitope], and partial N- or C-terminal deletions (with or without concomitant protein tagging). Because of the modular nature of the plasmids, they allow efficient and economical use of a small number of PCR primers for a wide variety of gene manipulations. Thus, these plasmids should further facilitate the rapid analysis of gene function in S. cerevisiae.

Assessment of the ruminant respiratory system.

With practice, complete use of the methods of this assessment: history, detailed examination of the head and neck, cough induction, chest auscultation and percussion, and chest auscultation following forced rebreathing can be completed within 10 minutes. The examination can provide a great deal of new information regarding the respiratory system that would go undetected on a more general physical examination. In cases in which the diagnosis is still in question or requires confirmation, this will also enable the optimal use of appropriate ancillary tests, as described in the article on ancillary testing for the respiratory tract elsewhere in this issue.

Borderline epithelial ovarian tumors: a review of 81 cases with an assessment of the impact of treatment.

Optimal management of borderline epithelial ovarian tumors remains controversial because of the lack of clear, universally accepted pathologic criteria for diagnosis, the lack of complete understanding of the significance of intraperitoneal implants, and the desire to employ more limited surgery in young women. We reviewed the experience with borderline epithelial ovarian tumors at Princess Margaret Hospital in order to assess the natural history of the disease, to determine prognostic factors that would aid in management decisions, and to determine if adjuvant therapy influenced outcome. Eighty-one patients were analyzed. The mean age was 48 years. Seventy-two percent of tumors were of the serous histologic sub-type and 28% were mucinous. Seventy-eight percent were Stage I, 11% Stage II, and 11% Stage III. Peritoneal washings contained malignant cells in 14 of 32 patients (not recorded or obtained in 49), cyst rupture occurred in 25%, surface excrescences in 40%, and adhesions in 46%. None of these factors had a significant effect on recurrence rate or survival. Eleven patients received adjuvant radiation therapy (10 abdomino-pelvic and 1 pelvic alone), four adjuvant chemotherapy, and one both radiation therapy and chemotherapy. The rest (65) received no adjuvant therapy. Due to the small numbers and infrequent events, it was not possible to analyze and thus draw valid conclusions regarding the effect of adjuvant therapy on survival or recurrence. The overall survival (OS) and cause specific survival (CSS) were 85% and 96% at 10 years, respectively. No Stage I patient died of tumor. OS for Stage I patients was 90% at 10 years, the majority of whom (61 of 63) received no adjuvant therapy, and is thus unnecessary in Stage I disease. The adequacy of unilateral oophorectomy or ovarian cystectomy could not be confirmed because of small numbers. The 10 year OS and disease-free survival in Stage II and III were 75% and 50%, respectively, despite the use of adjuvant radiation therapy, chemotherapy, or both. It is necessary to create a multi-center tumor registry in order to acquire a prospective data base from which to develop sound therapeutic decisions.