First description of the female of the jumping spider Balmaceda nigrosecta Mello-Leitão (Salticidae, Dendryphantini, Marpissina).

The female of Balmaceda nigrosecta Mello-Leitão, 1945 is described and illustrated for the first time. In addition, this paper further illustrates the male, and provides the first known observations on the natural history of this species, including habitat, cohabitation, and prey capturedata.

Freyinae, a major new subfamily of Neotropical jumping spiders (Araneae: Salticidae).

Freyinae, new subfamily, is described for a group of genera of Neotropical jumping spiders that can be distinguished from other non-ant mimic salticoid Neotropical salticids by having the following three morphological features: a slightly more elongate carapace, a distinctive prolateral tibial macrosetae arrangement (medially placed subdistal and subproximal macrosetae, with a subdorsal medial macroseta in some males), and an unusual dorsoventrally thick tegulum basal division (although one or two of these features are sometimes lost). It includes 20 genera previously considered valid, of which 19 are retained: Akela Peckham & Peckham, 1896, Aphirape C.L. Koch, 1850, Asaracus C.L. Koch, 1846, Capidava Simon, 1902, Chira Peckham & Peckham, 1896, Edilemma Ruiz & Brescovit, 2006, Eustiromastix Simon, 1902, Freya C.L. Koch, 1850, Frigga C.L. Koch, 1850, Kalcerrytus Galiano, 2000, Nycerella Galiano, 1982, Onofre Ruiz & Brescovit, 2007, Pachomius Peckham & Peckham, 1896, Phiale C.L. Koch, 1846, Rishaschia Makhan, 2006, Sumampattus Galiano, 1983, Trydarssus Galiano, 1995, Tullgrenella Mello­Leitão, 1941, and Wedoquella Galiano, 1984. Romitia Caporiacco, 1947 (and its synonym Uspachus Galiano, 1995) is synonymized with Pachomius, new synonymy. New genera described in the subfamily are: Drizztius, Leptofreya, Megafreya, Philira, Tarkas, Triggella, and Xanthofreya. The following nomenclatorial changes are made: New synonyms: Freya demarcata Chamberlin & Ivie, 1936 = Freya (sub Cyrene) albosignata (F.O.P.-Cambridge, 1901); Freya (sub Cyrene) grisea (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) infuscata (F.O.P.-Cambridge, 1901); Freya (sub Cyrene) emarginata (F.O.P.-Cambridge, 1901) and Nycerella (sub Heraclea) sanguinea paradoxa (Peckham & Peckham, 1896) = Nycerella (sub Heraclea) sanguinea (Peckham & Peckham, 1896); Pachomius (sub Phiale) maculosus (Chickering, 1946) = Phiale (sub Cyrene) bilobata (F.O.P.-Cambridge, 1901); Phiale (sub Cyrene) mediocava (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) maculatipes (F.O.P.-Cambridge, 1901); Phiale (sub Cyrene) simplicicava (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) bifurcata (F.O.P.-Cambridge, 1901). New combinations: Capidava rufithorax Simon, 1902 = Drizztius rufithorax; Freya frontalis Banks, 1929 = Eustiromastix frontalis; Chira (sub Attus) spinipes (Taczanowski, 1872) = Eustiromastix spinipes; Freya (sub Euophrys) ambigua (C.L. Koch, 1846) = Leptofreya ambigua; Freya (sub Cyrene) bifurcata (F.O.P.-Cambridge, 1901) = Leptofreya bifurcata; Freya (sub Cyrene) laticava (F.O.P.-Cambridge, 1901) = Leptofreya laticava; Freya (sub Cyrene) longispina (F.O.P.-Cambridge, 1901) = Leptofreya longispina; Phiale (sub Cyrene) bilobata (F.O.P.-Cambridge, 1901) = Pachomius bilo-batus; Phiale (sub Cyrene) hieroglyphica (F.O.P.-Cambridge, 1901) = Pachomius hieroglyphicus; Phiale (sub Cyrene) niveoguttata (F.O.P.-Cambridge, 1901) = Pachomius niveoguttatus; Romitia (sub Euophrys) albipalpis (Taczanowski, 1878) = Pachomius albipalpis; Romitia (sub Euophrys) andina (Taczanowski, 1878) = Pachomius andinus; Romitia (sub Uspachus) bahiensis (Galiano, 1995) = Pachomius bahiensis; Romitia (sub Uspachus) columbiana (Galiano, 1995) = Pachomius columbianus; Romitia (sub Uspachus) juquiaensis (Galiano, 1995) = Pachomius juquiaensis; Romitia (sub Phiale) ministerialis (C.L. Koch, 1846) = Pachomius ministerialis; Romitia (sub Uspachus) misionensis (Galiano, 1995) = Pachomius misionensis; Romitia nigra Caporiacco, 1947 = Pachomius nigrus; Romitia (sub Uspachus) patellaris (Galiano, 1995) = Pachomius patellaris; Chira (sub Diagondas) micans (Simon, 1902) = Philira micans; Chira superba Caporiacco, 1947 = Philira superba; Freya (sub Cyrene) maculatipes (F.O.P.-Cambridge, 1901) = Tarkas maculatipes; Freya (sub Cyrene) bifida (F.O.P.-Cambridge, 1901) = Triggella bifida; Freya infuscata (F.O.P.-Cambridge, 1901) = Triggella infuscata; Freya (sub Cyrene) minuta (F.O.P.-Cambridge, 1901) = Triggella minuta; Freya (sub Cyrene) albosignata (F.O.P.-Cambridge, 1901) = Xanthofreya albosignata; Freya arraijanica Chickering, 1946 = Xanthofreya arraijanica; Phiale (sub Cyrene) bicuspidata (F.O.P.-Cambridge, 1901) = Xantho-freya bicuspidata; Freya chionopogon Simon, 1902 = Xanthofreya chionopogon; Freya (sub Heraclea) rustica (Peckham & Peckham, 1896) = Xanthofreya rustica. Combinations restored: Phiale (sub Pachomius) flavescens (Peckham & Peckham, 1896) = Pachomius flavescens; Phiale (sub Pachomius) similis (Peckham & Peckham, 1896) = Pachomius similis. Invalid name: Freya dyali Roewer 1951 is an invalid replacement name for Euophrys trifasciata "Dyal 1935", which was a redescription of Euophrys trifasciata C.L. Koch, 1846, not a homonym. New species: Drizztius geminensis. First female descriptions and transfers of mismatched females: First descriptions for Asaracus megacephalus C.L. Koch, 1846, Capidava biuncata Simon, 1902, and Phiale formosa (Banks, 1909); the true female of Eustiromastix spinipes is described, and its mismatched female is identified as the female of Eustiromastix falcatus Galiano, 1981; the mismatched female of Freya (sub Cyrene) prominens (F.O.P.-Cambridge, 1901) is identified as the female of Xanthofreya rustica; the misidentified female of X. rustica is identified as the female of Leptofreya bifurcata. Lectotypes: designated for Cyrene bifida F.O.P.-Cambridge, 1901 and Cyrene formosa Banks, 1909. New synapomorphy: a constricted proximal end of the cymbium of the male palp is an apparent new synapomorphy for Salticoida.

The genus Myrmarachne (Araneae, Salticidae) in Flores, Indonesia.

Two new species of the genus Myrmarachne are described (Myrmarachne acutidens sp. n., Myrmarachne epigealis sp. n.), and Myrmarachne macrognatha and Myrmarachne melanocephala are redescribed from Flores specimens. The females of Myrmarachne macrognatha are recorded for the first time.

Do subcutaneous sutures increase risk of laparotomy wound suppuration?

REASONS FOR PERFORMING STUDY: Incisional drainage and suppuration occurs commonly following exploratory laparotomy; any technique with the potential to reduce the incidence of this complication warrants investigation. OBJECTIVES: To determine if abandoning the use of subcutaneous sutures in laparotomy wound closure is safe and whether it reduces the risk of suppuration. METHODS: A randomised controlled study was carried out at 2 referral hospitals in the UK, involving 309 horses undergoing exploratory laparotomy; 150 horses underwent '2-layer' closure without a subcutaneous suture, while 159 underwent conventional '3-layer' closure. Information regarding degree of oedema and gross types of discharge was recorded daily; suppuration was defined as discharge of pus. Telephone follow-up was carried out 30 days after hospital discharge to identify those complications occurring after that date and, thereafter, every 3 months. The influence of closure method on risk of wound suppuration was assessed by Chi-squared analysis and by logistic regression. Time to suppuration was modelled using a Cox proportional hazards model. RESULTS: No catastrophic failures of 2-layer closures were recorded. Prevalence of suppuration was not significantly different, being 18.7% and 23.9% for 2- and 3-layer closures, respectively (OR = 1.37, 0.79-2.37, P = 0.263). CONCLUSIONS AND POTENTIAL RELEVANCE: This study found no significant difference in prevalence or rate of wound suppuration in 2-layer closures compared to conventional 3-layer closure. Two-layer closure is recommended as a safe alternative means of achieving ventral midline abdominal closure in horses.

Differential survival in horses requiring end-to-end jejunojejunal anastomosis compared to those requiring side-to-side jejunocaecal anastomosis.

REASONS FOR PERFORMING STUDY: Horses requiring different methods of intestinal anastomosis during equine colic surgery may have differences in mortality and morbidity. HYPOTHESES: Horses requiring side-to-side jejunocaecal anastomosis have a higher mortality and morbidity rate than those requiring end-to-end jejunojejunal anastomosis. Morbidity and mortality of handsewn vs. stapled side-to-side jejunocaecal anastomoses are not significantly different. METHODS: A prospective, nonrandomised, observational study was conducted. Clinical and surgical details were recorded during hospitalisation and survival data acquired by periodic telephone questionnaire. Differences in mortality and morbidity rate were evaluated by survival analysis. RESULTS: A total of 184 horses underwent end-to-end jejunojejunal anastomosis and 178 underwent side-to-side jejunocaecal anastomosis. Horses with a jejunocaecal anastomosis had a significantly higher mortality rate. The incidence of post operative colic in horses requiring side-to-side jejunocaecal anastomoses was greater than those requiring end-to-end jejunojejunal anastomoses. Within the group undergoing side-to-side jejunocaecal anastomosis there was no evidence of differential survival between horses with handsewn vs. stapled anastomoses. CONCLUSIONS: Mortality rate is higher in horses that have required side-to-side jejunocaecal anastomosis than in those that needed end-to-end jejunojejunal anastomosis; and post operative colic is more common after side-to-side jejunocaecal anastomosis. No difference in mortality was found between horses with handsewn and stapled side-to-side jejunocaecal anastomoses. POTENTIAL RELEVANCE: Surgeons should be aware of the increased mortality and morbidity in horses requiring side-to-side jejunocaecal anastomosis. Our finding of no difference in mortality between handsewn and stapled side-to-side jejunocaecal anastomoses justifies surgeons exercising personal preference in their selection of anastomosis method.

Pre-operative and anaesthesia-related risk factors for mortality in equine colic cases.

Mortality rates for horses that have undergone emergency abdominal surgery are higher than for other procedures. Here, multivariable modelling of data from 774 surgical colic cases is used to identify pre-operative and anaesthesia-related variables associated with intra- and post-operative mortality. Intra-operative mortality was significantly (P<0.05), and positively associated with heart rate and packed cell volume (PCV) at admission, and negatively associated with the severity of pain. Post-operative mortality increased with increasing age and PCV at admission. Draught horses, Thoroughbreds and Thoroughbred-cross horses carried a significantly worse prognosis. We detected a small but significant variability in the risk of intra-operative death amongst referring veterinary surgeons. Different anaesthetic induction agents, inhalation maintenance agents and the use, or not, of intermittent positive pressure ventilation had no significant effect on risk of death. We conclude that cardiovascular compromise, level of pain, age, and breed are all associated with the risk of mortality in equine surgical colic cases.

Factors affecting long-term survival of horses recovering from surgery of the small intestine.

REASONS FOR PERFORMING STUDY: Epiploic foramen entrapment (EFE) has been associated with a particularly poor post operative prognosis for equine colic cases, but the reasons for this are unknown. OBJECTIVES: To identify variables associated with post operative survival following surgery for small intestinal disease; develop a model describing long-term post operative survival; and identify reasons for the poor prognosis associated with EFE. METHODS: Data from 382 horses undergoing surgery were used to identify variables associated with survival. A multivariable Cox proportional hazards model for post operative survival was developed and model fit evaluated. RESULTS: The final model included the variables total plasma protein (TP) and packed cell volume (PCV) at admission, duration of surgery and the dichotomous variable relaparotomy (yes/no). Risk of death was positively associated with increasing PCV, but negatively associated with increasing TP (which decreased the probability of death). In a univariable model, EFE cases had a significantly higher death rate than other types of small intestinal disease (hazard ratio = 1.7, P = 0.035). Multivariable modelling indicated that some of the increased risk associated with EFE cases was due to lower TP values and longer duration of surgery. CONCLUSIONS: Preoperative TP is associated negatively with the risk of post operative death in horses recovering from small intestinal surgery. Other variables associated with the probability of survival are preoperative PCV, duration of surgery and relaparotomy. The increased post operative death rate of EFE cases can be explained in part by lower TP and longer surgery times of these cases. POTENTIAL RELEVANCE: Total plasma protein may be not simply a measure of hydration status in small intestinal colic cases, but an important determinant of survival. Further investigation of this relationship is warranted. Our model for post operative survival highlights the importance of preoperative TP, PCV and duration of surgery as prognostic indicators. This information should allow a more accurate post operative prognosis following small intestinal surgery.

Modelling long-term survival of horses following surgery for large intestinal disease.

REASONS FOR PERFORMING STUDY: Large intestinal diseases are an important cause of equine colic that require surgical management, but there is little published information about long-term survival of such cases. OBJECTIVES: To identify variables associated with post operative mortality and to develop a model for post operative survival following surgery for large intestinal disease. METHODS: Clinical data and long-term follow-up information from 275 horses undergoing surgery for large intestinal disease were used. A multivariable, Cox proportional hazards model for post operative death was developed and the fit of the model evaluated. RESULTS: The continuous variables age, heart rate and packed cell volume (PCV) were associated positively with the risk of post operative death, as were the categorical variables resection (odds ratio [OR] 2.4, 95% confidence interval [CI] 1.2-5.1) and relaparotomy (OR 3.5, 95% CI 1.4-8.4). CONCLUSIONS: In the population studied, the probability of post operative survival following surgery for large intestinal disease was associated with the cardiovascular parameters heart rate and PCV on admission, age of the horse and whether it underwent resection or relaparotomy. POTENTIAL RELEVANCE: The prognosis for post operative survival for horses with large intestinal disease may be improved by early surgery, prior to the development of cardiovascular compromise. Surgeons should be aware that increasing age, resection of large colon and relaparotomy are all associated with a worsening prognosis for survival.

Evaluation of the clinical efficacy of prokinetic drugs in the management of post-operative ileus: can retrospective data help us?

The objectives of the study were to determine whether retrospective data can be used to answer questions about the efficacy of prokinetic agents when used to treat horses with post-operative ileus (POI). We describe prevalence and mortality of POI with reference to treatment with four prokinetic agents. By combining data from two Hospitals a study population of 55 horses with POI following pedunculated lipoma obstruction (PLO) was established. Univariable and multivariable associations were determined between short term survival and potential explanatory variables. With death as outcome in multivariable models, breed and hospital were significantly associated with outcome but the use of prokinetic agents was not (P=0.15). However, sample size estimates indicate the low power of this study to detect differences in outcome. It was not possible definitively to evaluate the efficacy of prokinetics as treatment for POI following PLO using retrospective data. The data were suggestive of limited efficacy of prokinetics as treatment for POI. It is postulated that the identified association between hospital and survival reflects differences in clinician decision making. The study highlights the need for further prospective studies using randomised clinical trials to evaluate accurately the efficacy of prokinetic agents. This report illustrates difficulties with performing retrospective analysis of clinical data to determine the efficacy of treatment regimes.

Suspected venous air embolism in a horse.

A horse which had had a caecal impaction for 10 days was treated by means of an ileocolostomy [corrected] but failed to respond satisfactorily. Before a second laparotomy was performed it was observed to have dislodged the extension set from a jugular catheter and air was heard being sucked into the vein. It became very agitated but was anaesthetised again and the impaction was removed through an incision in the apex of the colon [corrected] After recovering from the anaesthesia it developed severe signs of pruritus which subsided only after 12 hours. These signs were considered most likely to have resulted from a venous air embolism.

A review of some south american species of jumping spiders (Araneae: Salticidae) described by Mello-Leitão from Brasil, with resolution of the genus Asaphobelis

Os tipos de 18 espécies de Salticidae descritas por Mello-Leitão para o Brasil foram re-examinados e redescritos quando necessário. As seguintes mudanças nomenclaturais foram propostas: Novas sinonímias: Akela quinquevittata Mello-Leitão 1947 = Ilargus coccineus Simon 1901; Asaphobelis pluripunctatus Mello-Leitão 1947 = Asaphobelis physonychus Simon 1902; Asaracus elegantulus Mello-Leitão 1947 = Chira thysbe Simon 1902; Breda nigrotaeniata Mello-Leitão 1947 = Breda flavostriata Simon 1901; Phiale duplocellata Mello-Leitão 1947 = Phiale tristis Mello-Leitão 1945. Novas Combinações: Akela longibarba Mello-Leitão 1943 = Phiale longibarba (Mello-Leitão 1943); Marpissa broadwayi Peckham & Peckham 1892 (= Naubolus aureocomosus Mello-Leitão 1943) = Platycryptus broadwayi (Peckham & Peckham 1892); Saitis labyrintheus Mello-Leitão 1947 = Mopiopia labyrinthea (Mello-Leitão 1947) [lectótipo e paralectótipo designados]; Saitis tristis Mello-Leitão 1947 = Mopiopia tristis (Mello-Leitão 1947); Semora albibarbis Mello-Leitão 1947 = Tariona albibarbis (Mello-Leitão 1947); Asaphobelis fasciiventris Simon 1902 = Coryphasia fasciiventris (Simon 1902). Asaphobelis physonychus Simon 1902 agora e a única espécie no gênero. Outras espécies redescritas: Coryphasia castaneipedis Mello-Leitão 1947; Coryphasia nigriventris Mello-Leitão 1947; Cotinusa leucoprocta (Mello-Leitão 1947); Naubolus trifasciatus Mello-Leitão 1927; Phiale bipunctata Mello-Leitão 1947; Pseudofluda pulcherrima Mello-Leitão 1928; Semora langei Mello-Leitão 1947; e Titanattus pallidus Mello-Leitão 1943.

Septic tenosynovitis of the tarsal sheath of an Arab gelding and suspected sepsis of the lateral digital flexor tendon subsequent to bacterial peritonitis.

A 21-year-old Arab gelding with clinical signs of acute peritonitis had a perforating ulcer on the mesenteric border of the jejunum which resulted in localised contamination of the abdomen with ingesta. The affected segment of jejunum was resected and the abdomen was lavaged extensively. Postoperatively, the gelding was treated with broad-spectrum antibiotics, non-steroidal anti-inflammatory drugs and intravenous fluids, but after four days it became acutely non-weight bearing on its right hindlimb, and a tendonitis of the lateral digital flexor tendon within the tarsal sheath was identified ultrasonographically. The septic tendonitis was treated with broad-spectrum antibiotics but progressed proximodistally within the tendon until it involved both the tarsal sheath and the associated tarsocrural joint, necessitating the euthanasia of the gelding.

Interstitial cells of Cajal (ICC) in equine colic: an immunohistochemical study of horses with obstructive disorders of the small and large intestines.

REASONS FOR PERFORMING STUDY: The gastrointestinal pacemaker cells, the interstitial cells of Cajal (ICC), have been implicated in several human gastrointestinal dysmotility syndromes. Recently, the involvement of these cells in equine gastrointestinal diseases has been investigated in cases of equine grass sickness where a significant reduction in ICC density was observed. OBJECTIVE: To investigate ICC density in equine obstructive gastrointestinal disorders using immunohistochemical labelling methods. METHODS: Intestinal samples were analysed from 44 horses undergoing exploratory surgery for colic and from 11 control animals subjected to euthanasia for conditions not related to the gastrointestinal tract. Immunohistochemical labelling of ICC was carried out using an anti-c-Kit antibody. Two independent observers assessed ICC density using a semiquantitative grading system. RESULTS: There was a significant reduction in ICC density in horses with large colon disorders compared to the controls (P<0.01). Horses with strangulating lesions of the small intestine showed no difference when compared to the controls. CONCLUSIONS: There was a reduction in ICC density in horses with large intestinal disorders. POTENTIAL RELEVANCE: The reduction in ICC density may be associated with the clinical findings as well as recurrent colic episodes observed in a number of these cases. This immunohistochemical study provides a basis for future functional electrophysiological investigations to determine the precise effect of ICC reduction on equine intestinal motility.

Reports of envenomation by brown recluse spiders (Araneae: Sicariidae) outnumber verifications of Loxosceles spiders in Florida.

Bites attributed to the brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, are frequently reported by medical personnel throughout Florida, whereas the extensive arachnological evidence contradicts the alleged widespread occurrence of Loxosceles spiders in the state. We compared reports of brown recluse spider bites made by medical personnel from a 6-yr Florida poison control center database to the known verifications of Loxosceles spiders from 100 yr of Florida arachnological data. Medical personnel diagnosed 124 brown recluse spider bites from 31 of Florida's 67 counties in 6 yr. In contrast, only 11 finds of approximately 70 Loxosceles spiders have been made in 10 Florida counties in 100 yr. Florida does not have sufficient widespread populations of Loxosceles spiders to warrant consideration of brown recluse spider envenomation as a probable etiology of dermonecrosis. Florida health care would improve if medical personnel would consider the multitude of other etiologies that manifest in dermonecrosis.

Equine grass sickness is associated with low antibody levels to Clostridium botulinum: a matched case-control study.

REASONS FOR PERFORMING STUDY: Equine grass sickness is a high mortality disease which, despite many years of investigation, is of unknown aetiology. Recent findings indicating that the disease is associated with Clostridium botulinum require support from an epidemiological study that recognises and controls for potential confounders, e.g. age, time of year and premises. HYPOTHESIS: EGS is associated with low antibody levels to C. botulinum antigens. METHODS: A matched case-control study was conducted. Data were collected from 66 histologically confirmed cases of EGS and 132 premises-matched control horses. The probability of EGS in horses was modelled using conditional logistic regression. RESULTS: EGS was significantly associated (age-adjusted P < 0.005) with low antibody levels to each of 3 clostridial antigens; C. botulinum type C and C. novyi type A surface antigens and a C. botulinum type C toxin complex toxoid. These serological risk factors for EGS remained highly significant when entered into multivariable models. This study also identified new horse-level risk factors for EGS; feeding hay or haylage was associated with a decreased risk of disease, change of feed type or quantity during the 14 days prior to disease was associated with increased risk, and the use of an ivermectin anthelmintic at both the ultimate and penultimate treatments was also associated with a significantly increased risk of EGS. CONCLUSIONS: This study provides strong support for the role of C. botulinum in the aetiology of EGS and identifies managemental risk factors for the disease. POTENTIAL RELEVANCE: Increasing anticlostridial antibody levels by vaccination and appropriate managemental interventions may decrease the risk of EGS occurring.

Why are certain premises at increased risk of equine grass sickness? A matched case-control study.

REASONS FOR PERFORMING STUDY: Equine grass sickness (EGS) occurs repeatedly on certain premises over time. Few studies have sought, or identified, the determinants of this phenomenon in order to inform advice on disease prevention strategies. HYPOTHESIS: Premises-level risk factors are important determinants of whether EGS occurs. METHODS: A matched case-control study was undertaken. Sixty premises giving rise to one or more histologically confirmed case of EGS and 120 time-matched control premises were sampled. Data were collected on pasture management, soil nutrient content, pasture nutrient content and local weather conditions for 2 weeks prior to the onset of disease. Data were analysed by conditional logistic regression. RESULTS: Multivariable modelling identified an association between EGS and increased soil nitrogen content, pasture disturbance and previous occurrence of EGS on the premises. None of the meteorological variables recorded in this study were significantly associated with EGS occurrence. No relationship between certain management practices (e.g. harrowing, fertilisation, reseeding) and the risk of EGS was detected. CONCLUSIONS AND POTENTIAL RELEVANCE: This information is useful in understanding the causal pathway of EGS and may be used in the formulation of evidence-based disease avoidance strategies.

Entrapment of the small intestine in the epiploic foramen in horses: a retrospective analysis of 71 cases recorded between 1991 and 2001.

The clinical features of 71 cases in 70 horses in which part of the small intestine became entrapped in the epiploic foramen are described. The horses' sex, age and breed, the month during which they were affected, and whether they exhibited stereotypic behaviour were compared with the same variables in 1279 horses which suffered other types of surgical colic during the same period. Thoroughbred and thoroughbred cross horses were over-represented among the 70 affected horses. There was no age or sex predilection. Fifty-five (77.5 per cent) of the cases occurred between October and March and 15 (21.1 per cent) occurred in January. The cases were significantly more likely to have a history of crib-biting/windsucking than the control group (odds ratio 7.9, 95 per cent confidence interval 4.1 to 15.3). The condition had recurred in two of the horses. Fifty-eight (81.7 per cent) recovered from surgery and 49 (69 per cent) survived until they were discharged from hospital. The median survival time of 31 of the affected horses discharged from the hospital was 700 days, whereas 417 horses with other types of surgical colic had a median survival time in excess of 1931 days.

Long-term survival of equine surgical colic cases. Part 1: patterns of mortality and morbidity.

Postoperative complications and mortality can occur many weeks or months after colic surgery. We are interested in the long-term outcome of these cases. This study documents patterns of mortality and morbidity among 341 horses that recovered from colic surgery March 1998-August 2000. The progress of each horse was rigorously followed by periodic telephone and postal questionnaires. Event time data were recorded for each animal and a total of 321 horse years of survival, together with death from all causes, colic-related death and various postoperative complications. Postoperative survival (of all horses excluding grass sickness cases) was triphasic over the first 600 days and there was marked mortality in the first 10 days postoperatively. The probability of survival postoperatively decreased to 0.87 by 10 days, 0.82 by 100 days and declined slowly to 0.75 at 600 days. Horses suffering from epiploic foramen entrapment had a significantly reduced probability of postoperative survival (RR = 2.1, P = 0.033). The causes of death for 104 horses that died postoperatively and the prevalence of postoperative complications are recorded for the study population. Postoperative colic was the most prevalent complication with 100 horses (29%) suffering one or more episodes. However, only 16 horses (4.6%) suffered 3 or more episodes. The incidence of postoperative colic was 0.55 episodes/horse year at risk. This study provides data that will inform the prognosis for postoperative colic cases and identifies epiploic foramen entrapment as carrying a worse prognosis for survival than other strangulating lesions.

Long-term survival of equine surgical colic cases. Part 2: modelling postoperative survival.

Colic surgery is a frequently performed operation with high postoperative mortality. This study was undertaken to identify variables associated with decreased postoperative survival. We used data from 321 horse years of postoperative survival time to model the probability of survival following recovery from colic surgery. Continuous variables were modelled using a 6 variable, penalised Cox regression model. This demonstrated approximately linear relationships between survival and the following variables: increase in packed cell volume (PCV), intestinal resection length, time to surgery (interval between onset of colic and surgery) and duration of surgery. No significant decrease in survival was demonstrated with increasing age of the patient or with heart rate. The only categorical variable to be significantly associated with decreased survival was epiploic foramen entrapment. The final, fixed effects Cox proportional hazards model of postoperative survival included the variables epiploic foramen entrapment, PCV, resection length and duration of surgery, each variable adjusted for the nonlinear relationship with time to surgery. Residual variation in postoperative survival attributable to professional personnel (referring veterinary surgeon, anaesthetist and surgeon) was explored by fitting each as a random effects term in the model. Little of the residual variation could be attributed to any category of personnel. Model diagnostics indicated little influence by individual outliers on model parameters and little evidence of subjects poorly predicted by the final model. The study highlights factors influencing the long-term survival of horses recovering from colic surgery and proposes a model that can be used to inform prognosis.