Topic:Mortality
Mortality in horses refers to the incidence and causes of death within equine populations. Understanding mortality is important for assessing health risks, improving management practices, and guiding veterinary care. Various factors contribute to mortality in horses, including age, breed, health status, and environmental conditions. Common causes of death in horses include colic, injury, infectious diseases, and age-related conditions. Mortality rates and patterns can vary significantly depending on the population and geographic location. This page compiles peer-reviewed research studies and scholarly articles that investigate the epidemiology, causes, and trends of mortality in horses, providing insights into preventive measures and management strategies to reduce mortality rates.
Caesarean section and other methods for assisted delivery: comparison of effects on mare mortality and complications. Data from 116 mares that had caesarean section or vaginal delivery at 2 university hospitals were analysed in 5 groups, as follows: dystocia corrected by caesarean section, Group DCS (n = 48); elective caesarean section, Group ECS (n = 10); caesarean section concurrently with colic surgery, Group CCS (n = 8); assisted vaginal delivery, Group AVD (n = 22); and controlled vaginal delivery under general anaesthesia, Group CVD (n = 28). Survival rate in all mares that had caesarean section, excluding Group CCS, was 88% (51/58). All mares in Group ECS survived and Group CCS had the lowest survival ...
Injuries to riders in the cross country phase of eventing: the importance of protective equipment. To determine the distribution of injuries in the eventing discipline of equestrian sports and the effectiveness of the protective equipment worn. Methods: Data on all injuries sustained in the cross country phase over fixed obstacles were collected from 54 days of competition from 1992 to 1997. This involved 16,940 rides. Results: Data on a total of 193 injuries were collected, which included two deaths. This represents an injury rate of 1.1%. Head and facial injuries represented the largest group (31%), with one third of these requiring treatment in hospital. All riders were wearing protectiv...
Mortality supposedly due to intoxication by pyrrolizidine alkaloids from Heliotropium indicum in a horse population in Costa Rica: a case report. This article describes a case of massive mortality among horses which was probably due to intoxication by pyrrolizidine alkaloids from Heliotropium indicum. Over 4 years more than 75% of a population of about 110 horses on a farm in Costa Rica died after showing nervous neurological symptoms. Two clinical manifestations were encountered, an acute and a chronic one, both with a fatal outcome. Pathological findings in 2 horses coincided with those reported in the literature for intoxication by pyrrolizidine alkaloids and were not specific for VEE. However Venezuelan equine encephalitis (VEE) was...
Dissecting aortic aneurysm in a horse. A case of dissecting aortic aneurysm in a 4-year-old male thoroughbred horse is reported. The horse had a history of inflammation in the right thigh and a fever 2 weeks before sudden death. At necropsy, aortic aneurysms were observed from the aortic valve to the aortic arch, spreading over a distance of 40 cm. An irregular rupture of the intima of the ascending aorta was located in the cardiac side of a ramification to the tunica branchiocephalicus communis. An intramural haematoma, apparent on the cut surface and in the pericardium, had caused cardiac tamponade and sudden death.
Hyperkalaemic periodic paralysis in homozygous and heterozygous horses: a co-dominant genetic condition. Historical, clinical and experimental data were collected from 9 horses homozygous for HYPP (H/H). All showed episodes of respiratory stertor, described as a rattling or honking sound, usually within the first week post partum. Five horses had one or more episodes of dysphagia, in 3 horses this was accompanied by drooling and in 3 by weight loss. In comparison, only one of 35 contemporaneous half siblings (of which approximately half would be expected to be of the H/N genotype and half N/N) was observed to have respiratory stertor prior to weaning and none had problems with dysphagia. One matu...
Presumed moxidectin toxicosis in three foals. Outcome and complications associated with administration of moxidectin gel to 3 foals < 4 months old are described. Two foals became comatose but survived following supportive treatment. One foal died following loss of consciousness associated with moxidectin administration. Risk of moxidectin overdose exists, because horse owners often fail to read or comprehend the package insert instructions pertaining to use of the syringe-locking mechanism. In addition, moxidectin should not be administered to foals < 4 months old, because it is likely that treated foals will become comatose.
Rider injury rates and emergency medical services at equestrian events. Horse riding is a hazardous pastime, with a number of studies documenting high rates of injury and death among horse riders in general. This study focuses on the injury experience of cross country event riders, a high risk subset of horse riders. Methods: Injury data were collected at a series of 35 equestrian events in South Australia from 1990 to 1998. Results: Injury rates were found to be especially high among event riders, with frequent falls, injuries, and even deaths. The highest injury rates were among the riders competing at the highest levels. Conclusions: There is a need for skilled...
Characteristics and risk factors for failure of horses with acute diarrhea to survive: 122 cases (1990-1996). To characterize horses with acute diarrhea and determine risk factors for failure to survive. Methods: Retrospective study. Methods: 122 adult horses admitted for acute diarrhea at the teaching hospital between Jan 1, 1990 and Dec 31, 1996. Methods: Medical records of horses with acute diarrhea were reviewed to abstract information regarding signalment, history, physical examination, clinicopathologic testing, treatment, and outcome. Results: 91 of 122 (74.6%) horses lived and were discharged from the hospital. Horses with history of administration of antimicrobials for a problem preceding dia...
Evaluation of enterolithiasis in equids: 900 cases (1973-1996). To identify breed, age, sex, physical findings, history, and outcome of treatment in horses and other equids with enterolithiasis. Methods: Retrospective study. Methods: 900 equids with enterolithiasis. Methods: Medical records from equids with enterolithiasis admitted between 1973 and 1996 were reviewed. Data on signalment, history, physical examination and clinicopathologic findings, surgical findings, and outcome were compiled from records and from telephone interviews with owners. Sex and breed predilections were determined by comparison of the study population with the general hospital po...
Prevalence of beta2-toxigenic Clostridium perfringens in horses with intestinal disorders. The incidence of a new, yet unassigned toxin type of Clostridium perfringens containing the genes for the alpha-toxin and the recently described beta2-toxin in horses with intestinal disorders is reported. The study included 18 horses suffering from typical typhlocolitis, 7 horses with atypical typhlocolitis, 16 horses with other intestinal disorders, and 58 horses without intestinal disease. In total, 20 samples of ingesta of the small and large intestines, five biopsy specimens of the intestinal wall, and 74 fecal samples were analyzed bacteriologically. C. perfringens isolates were typed fo...
Cecocolic and cecocecal intussusception in horses: 30 cases (1976-1996). To determine the prognosis in horses with cecocolic or cecocecal intussusception. Methods: Retrospective study. Methods: 30 horses with cecocolic intussusception or cecocecal intussusception. Methods: Information on history, physical examination findings, and laboratory values was summarized from the medical records. Laboratory data included results of hematologic examination, serum biochemical analysis, and peritoneal fluid color, total nucleated cell count, and total protein concentration. A one-year follow-up via the telephone was used to determine long-term survival. Results: Horses ranged...
Enterotoxigenic Clostridium perfringens type A necrotic enteritis in a foal. A Thoroughbred-Quarter Horse crossbred foal developed hemorrhagic enteritis and died < 48 hours after birth. Gross and histologic findings were suggestive of Clostridium perfringens type C infection, and large numbers of C perfringens were isolated from intestinal contents. However, genotyping of isolates indicated that they were enterotoxigenic C perfringens type A, and isolates were found to produce C perfringens enterotoxin in vitro. This case suggests that enterotoxigenic C perfringens type A may cause enteric disease in horses.
Influence of fecal shedding of Salmonella organisms on mortality in hospitalized horses. To predict mortality of horses by use of clinical data from the first day of hospitalization, to determine whether fecal shedding of Salmonella organisms is related to severity of clinical disease, and to determine the impact of fecal shedding of Salmonella organisms on mortality. Methods: Prospective study. Methods: 1,446 hospitalized horses. Methods: Medical information was obtained from horses hospitalized in an intensive care unit or isolation facility during a 4.5-year period. A model was created to predict mortality, using covariates determined on the day of admission. Predicted mortalit...
Endocrinology of pregnancy: chorionic somatomammotropins and pregnancy-associated glycoproteins: review. The two main groups of placental proteins of ruminants are discussed in this paper: chorionic somatomammotropins (placental lactogens) and pregnancy-specific (-associated) proteins. Placental lactogens belong to the prolactin and growth hormone family. They stimulate mammogenesis, fetal growth and maternal metabolism. Pregnancy-specific proteins and pregnancy-associated glycoproteins belong to the aspartic proteinase family like pepsin, cathepsin D and E. These two groups of proteins are secreted in the maternal circulation by the binucleate cells after their migration to and fusion with the u...
Arboviral infections of the central nervous system–United States, 1996-1997. Arboviruses include mosquitoborne and tickborne agents that persist in nature in complex cycles involving birds or mammals, including humans. Arboviral infection can cause fever, headache, meningitis, encephalitis, and sometimes death. During 1996-1997, health departments in 19 states reported to CDC 286 confirmed or probable cases (eight fatal) of arboviral encephalitis in humans (132 cases in 1996 and 154 provisionally in 1997). Surveillance programs in 18 states detected enzootic arboviral activity in mosquito or sentinel or wild bird populations, and cases of arboviral disease were recogni...
Datura seed intoxication in two horses. A sunflower-based feed supplement grossly contaminated with the seed of a Datura sp. resulted in severe signs of poisoning in 2 horses. One horse died peracutely of acute gastric dilatation and rupture following ingestion of the contaminated feed. The 2nd horse developed unresponsive paralytic ileus that led to euthanasia. Examination of the feed and gastrointestinal contents of both horses showed a high proportion of the characteristic Datura sp. seeds. The clinical signs and pathology in both cases were consistent with intoxication by the parasympatholytic alkaloid components of Datura sp.
Dung-derived biological agents associated with reduced numbers of infective larvae of equine strongyles in faecal cultures. Two sets of dung-derived organisms from soil routinely fertilized with manure (MA) and soil chemically fertilized (CH) were cultured separately in the laboratory. Baermannized organisms from these cultures were added to 20 g of faeces from strongyle-infected horses to form three treatment groups: (i) no soil organisms; (ii) low inoculum of soil organisms containing all organisms present in a suspension of approximately 100 adult female free-living nematodes; and (iii) high inoculum containing those soil organisms present with approximately 1000 adult female free-living nematodes. Three studies...
Randomized controlled trial of effects of Escherichia coli antiserum on serum immunoglobulin G concentrations and morbidity and mortality rates in foals. To determine whether administration of commercially available Escherichia coli antiserum to neonatal foals would affect serum IgG concentration or morbidity and mortality rates during the first 60 days of life. Methods: Randomized controlled trial. Methods: 271 neonatal foals on 4 well-managed farms. Methods: Foals were randomly assigned to a treatment or control group. All foals were allowed to suckle colostrum normally. In addition, treatment-group foals were given E coli antiserum (10 micromilligrams) orally between 0 and 8 hours after birth. Serum samples were obtained between 18 and 36 ho...
Enterocolitis associated with Clostridium perfringens infection in neonatal foals: 54 cases (1988-1997). To identify clinical signs, physical examination findings, results of diagnostic tests, treatments administered, and clinical outcome of neonatal foals with enterocolitis associated with Clostridium perfringens infection. Methods: Retrospective study. Methods: 54 neonatal foals. Results: Most foals had acute onset of obtunded mentation, colic, or diarrhea and developed leukopenia, neutropenia, an abnormally high number of band neutrophils, toxic WBC, and hypoproteinemia within 24 hours after admission, despite high serum IgG concentrations (> 800 mg/dl). Abdominocentesis and abdominal radiogra...
Type-II renal tubular acidosis and ventricular tachycardia in a horse. A 14-year-old Arabian mare was admitted for lethargy, anorexia, and low fecal output. On the basis of laboratory, physical examination, and electrocardiographic findings, diagnoses of type-II renal tubular acidosis (RTA), impaction of the large colon, and ventricular tachycardia were made. Diagnosis of type-II RTA was based on measurement of a low fractional excretion value for potassium and fractional excretion value for sodium within the reference range. In contrast, horses with type-I RTA have high fractional excretion values for sodium and fractional excretion values for potassium within r...
A retrospective study of mortality associated with general anaesthesia in horses: emergency procedures. A retrospective study evaluated 995 emergency equine general anaesthetics. The total mortality for emergency procedures was 31.4 per cent. This figure was examined in more detail to determine if all emergency procedures carried a similar risk. Horses anaesthetised for surgical colic had an increased risk of death or euthanasia, with a total mortality of 35.5 per cent when compared to horses anaesthetised for non-colic related problems which had a total mortality of 15.3 per cent. The findings of this study illustrate the greatly increased risk of mortality in horses undergoing general anaesthe...
A retrospective study of mortality associated with general anaesthesia in horses: elective procedures. A retrospective analysis examined mortality associated with all procedures requiring general anaesthetic, performed at the Philip Leverhulme Large Animal Teaching Hospital, during the five-year period from February 1991 to December 1995. The study involved details relating to 2276 equine general anaesthetics and a variety of patient variables were examined. Within a group of 1279 animals undergoing anaesthesia for elective procedures, 46 (3.6 per cent) died or were euthanased owing to a poor prognosis or financial implications. Mortality relating directly to the surgery or anaesthesia occurred...
An epizoological study of wastage in thoroughbred racehorses in Gauteng, South Africa. Wastage is the term used to describe the phenomenon of the loss of racehorses from conception to adulthood due to death or injuries (i.e. they never reach a race-track), or the days lost by racehorses due to not training or being withdrawn from a race. This epizoological study was conducted to investigate wastage in Thoroughbred horses used for flat racing in the Gauteng Province of South Africa. Data from 6 racing stables were recorded from 1 March 1993 to 28 February 1994. Each trainer completed a daily training record of the horses in his stable. This questionnaire included reasons why a ho...
Neonatal equine herpesvirus type 1 infection on a thoroughbred breeding farm. Of 17 foals born on a Thoroughbred breeding farm between March and April 1995, infection with equine herpesvirus type 1 (EHV-1) was associated with neonatal morbidity in 5 foals, 3 of which died or were euthanized. Morbidity and mortality were associated with pulmonary inflammation, and EHV-1 was identified in the lungs of the 3 foals that died. All neonatal EHV-1 infections occurred in foals of mares housed in the same pasture and barn. No other clinical manifestations of EHV-1 infection (e.g., abortion, neurologic disease, or respiratory disease) occurred during this outbreak. Three foals we...
Hemostatic and fibrinolytic indices in neonatal foals with presumed septicemia. Thirteen coagulation tests evaluating hemostatic and fibrinolytic indices and serum cytokine and plasma endotoxin concentrations were obtained in 34 foals with a positive sepsis score (septic group) and 46 age-matched healthy foals. Compared to healthy foals, the prothrombin, activated partial thromboplastin, and whole blood recalcification times were significantly longer in septic foals. The fibrinogen and fibrin degradation products concentrations, percent plasminogen, alpha-2 antiplasmin, and plasminogen activator inhibitor activities, and tumor necrosis factor and interleukin-6 activities ...
Idiopathic hypocalcemia in foals. Five thoroughbred foals (4 fillies and 1 colt), all in good to excellent body condition, ranging in age from 4 days to 5 weeks at the time of onset of signs, were presented to 2 Kentucky equine hospitals from 1992 through 1996. All 5 foals presented with tachycardia, hyperhidrosis, diarrhea or a recent history of diarrhea, and muscle rigidity or stiff gait. Four of the 5 foals presented for recumbency, seizure-like activity with opisthotonos, or pronounced extensor muscle rigidity. All 5 foals were hypocalcemic. All foals either died or had euthanasia performed. None responded to oral calcium ...
Emericella nidulans as an agent of guttural pouch mycosis in a horse. A case is reported in a 9-year-old Anglo-Arab horse with guttural pouch mycosis caused by Emericella nidulans. Acute death occurred by exsanguination following erosion of the external carotid artery. Histopathological examination of the mycotic plaque demonstrated septate hyphae, conidial heads, hülle cells and mature cleistothecia containing characteristic ascospores. Specific identification was confirmed by culture. In accordance with previous reports, Emericella nidulans should be considered as the major agent of guttural pouch mycosis in Equidae.
Recurrent colic in the mature horse: a retrospective review of 58 cases. The clinical features of 58 horses presenting with recurrent colic examined over a 5 year period were reviewed. The horses were categorised into 3 groups on the basis of the history of colic episodes. Recurrent transient colic Group 1 was characterised by 3 or more episodes of transient colic (of apparently similar type) occurring within one month. Recurrent transient colic Group 2 was characterised by 3 or more episodes of transient colic occurring within one year. Recurrent prolonged colic was characterised by 3 or more episodes of prolonged colic occurring within one year. Fifteen horses we...
Prospective study of equine colic incidence and mortality. A prospective study of one year was conducted on 31 horse farms to obtain population based estimates of incidence, morbidity and mortality rates of equine colic. Farms with greater than 20 horses were enrolled by randomly selecting horse owners from 2 adjacent counties of Virginia and Maryland. Descriptive information for 1427 horses was collected at the initiation of the study and updated at 3 month intervals. Time on the farm during the study was tabulated for each horse. When colic was reported by the owner, investigators visited the farm to obtain information about the colic. The crude inc...