Indian Journal of Animal Research

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Indian Journal of Animal Research, volume 57 issue 1 (january 2023) : 48-57

Evaluation of Clinical, Laboratory and Ultrasonography Variables as Prognostic Indicators in Equine Colic Surgery

Gurpal Singh1, Vandana Sangwan1,*, Arun Anand1, Jasmeet Singh Khosa1, Simrat Sagar Singh1, Jitender Mohindroo1, Kuldeep Gupta2, Ram Saran Sethi3
1Department of Veterinary Surgery and Radiology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana-141 004, Punjab, India.
2Department of Veterinary Pathology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana-141 004, Punjab, India.
3College of Animal Biotechnology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana-141 004, Punjab, India.
Cite article:- Singh Gurpal, Sangwan Vandana, Anand Arun, Khosa Singh Jasmeet, Singh Sagar Simrat, Mohindroo Jitender, Gupta Kuldeep, Sethi Saran Ram (2023). Evaluation of Clinical, Laboratory and Ultrasonography Variables as Prognostic Indicators in Equine Colic Surgery . Indian Journal of Animal Research. 57(1): 48-57. doi: 10.18805/IJAR.B-4264.
Background: Equine colic surgery is an expensive procedure and availability of reliable prognostic indicators aid in decision making process. This study aimed to evaluate clinical, hemato-biochemistry, ultrasonography, surgery and peritoneal cytology / intestinal histology as prognostic indicators (based on strangulating vs non-strangulating lesion) for equine colic surgery. 

Methods: Fifteen equines {13 females and 2 males; 5 Thoroughbred, 9 Marwari and one mule} operated for intestinal colic were investigated. The feeding history, pre and post-surgery clinical, hematological and biochemical findings were recorded. Pre and post-surgery ultrasonography, peritoneal cytology and intestinal histology were done. Three equine were euthanized intra-operatively and 12 were followed for short and long term outcome. 

Result: On surgery, three equine were diagnosed for strangulating (right dorsal displacement of large colon, large colon volvulus and small colon strangulation) and 12 for non-strangulating colic {impaction (3), fecalith (5), sand colic (2), foreign body (1) and small intestine ileus (1)}. Detection of polymorphonuclear cells alone or with lymphocytes on peritoneal fluid cytology was indicator of good prognosis. Feeding of wheat straw is major predisposing factor for non-strangulating colic in Marwari breed but had favorable surgical prognosis (7/9=77.78%). While Thoroughbreds, not on wheat straw, are susceptible to strangulating colic that require early referral for favorable surgical outcome. Prolonged capillary refill time, injected mucous membranes, absent borborygymi, high serum creatine kinase and glucose are poor prognostic indicators for colic surgery. Thoroughbred equine with severe pain, elevated levels of Hb, neutrophils, packed cell volume (PCV), serum glucose and low peritoneal total protein are indicators of strangulating lesion. The equine colic surgery bears a very good short term (10/12=83.33%) and excellent (10/10=100%) long term outcome. 
Colic, of gastrointestinal origin, is the major cause of morbidity, mortality and premature deaths in horses (Cook and Hassel, 2014). Diagnostic approaches help to identify the nature and severity of most probable cause of colic, which helps for early referral; thereby, reducing the tissue injury and resulting endo-toxemia/ systemic inflammatory response syndrome and thus improving the survival rates. Recent studies reveals elevated plasma levels of lactate (Henderson, 2013), creatine kinase and AST activity (Krueger et al., 2014) as important prognostic indicators. Mucous membrane is prognostic indicator of hypovolemic shock/ endotoxemia with peritoneal fluid colour and lactate as indicators of strangulating and non-strangulating lesions (Shearer et al., 2018).

Surgical treatment of equine colic is resource-demanding and expensive; thus information on the prognosis is important both for owners as well as surgeons (Christophersen et al., 2014). This institute is working on the development of equine colic surgery including its diagnostic and prognostic aspects from the last a few years (Anand et al., 2017; Khosa et al., 2019a). The present study evaluated clinical, hemato-biochemical, ultrasonography and peritoneal cytology/ intestinal histology as the prognostic indicators for equine colic surgery along with post-surgical outcome.
This prospective clinical study (duly approved by the Institutional Animal Ethics Committee) was conducted on 15 equines, at the Referral University Veterinary Hospital, during December 2018 to December 2019.

The parameters recorded included Signalment and history (age, breed, gender, weight, duration of colic, mental state at presentation, pain and abdominal distension), Feeding history (feed type, recent change, history of diarrhea, de-worming and previous colic), Physical examination (borborygmi, nasogastric reflux/intubation, abdominocentesis and rectal examination), Clinical Examination (body temperature (p F), heart rate (HR, beats/min), Respiration rate (RR, breaths/min), Capillary refill time (CRT, /sec) and Mucous membrane color (MM)), Hematology and Serum Biochemistry {Hemoglobin (Hb), Total leukocyte count (TLC), Differential leukocyte count (DLC), Packed cell Volume (PCV), Platelets, lactate, total proteins, creatine kinase, alkaline Phosphatase (AKP), Na, K, Cl, Ca and glucose}, Abdominocentesis and peritoneal fluid analysis (Peritoneal fluid, collected intra-operatively or post-operatively was analyzed for cytology, lactate, creatine kinase and total proteins), Operative findings, Histopathology of affected intestines and Ultrasonography (B-mode ultrasonography was done pre and post operatively using 2-5 MHz frequency curvilinear transducer of GE HEALTHCARE LOGIQ F8 system to assess peritoneal fluid and intestinal motility).
Surgical procedure
All 15 equines were operated from ventral midline incision in dorsal recumbency under general anaesthesia (inhalant) as described by Khosa et al. (2019a). Inj. Normal saline (@ 10 ml/kg/hour) was administered throughout the surgery.
Patient monitoring
Anaesthetic recovery was monitored till animal stood up. Supportive bandage (using broad cotton tape) was applied for 12-14 days (Fig 3). Clinical and hemato-biochemical parameters were recorded daily during hospitalization. Lukewarm water intake in small frequent amounts was encouraged 12 hr after surgery, while green fodder/grazing intake and light walk at 24hrs.
Post-operative treatment
Inj. piperacillin and tazobactam @50mg/kg bid IV, inj. amikacin @5mg/kg bid IM and Inj. Flunixin @ 1.1 mg/kg, once daily, IV for 7, 5 and 3 days, respectively were administered. Intravenous fluids with balanced electrolytes were administered for 2 to 3 days. Lignocaine was used as a prokinetic @1.3 mg/kg, slow IV with half of calculated dose as loading dose and rest @0.05 mg/kg/hr.
Follow up and Clinical outcome
All the operated equines were followed for short (period of hospitalization after colic surgery i.e 3 to 5 days) and long term (period from discharge from the hospital upto 4 to 16 months) outcome.
Statistical analysis
The Microsoft excel 10 and SPSS 16 was used to calculate the descriptive statistics and student t-test to analyse significant difference between the survivors and non-survivors.
Signalment (Table 1)
Majority of the operated equines were females (13/15=86.66%). Gender itself was not associated with prevalence of colic but it has been associated with particular cause of colic such as uterine torsion in females (Khosa et al., 2019b) and scrotal hernia in intact males (Cook and Hassel, 2014).

Seven equines were presented in the month of December and January, which are winter months (temperature range 4 to 20oC) in the region of study. The other 8 equines were dispersed throughout the year. Winter season had been reported to be more likely for impactive colic due to decreased availability of green fodder and water intake (Southwood, 2013; Bihonegn and Bekele, 2018). However, for large colon volvolus, summer and spring season were reported as predisposing (Hackett et al., 2015); although, a volvolus case in the present study was presented in winter season.

Both young (£ 2yrs) and adult (>2yrs) equines were almost equally presented for surgery with a mean ±SD for age of 48.10 ± 45.67 months (range 2 month to 13 years). The short and long term survival was better in young equines as compared to that in adult. Age has been reported to be asssociated with specific types of colic (Cook and Hassel 2014, Bihonegn and Bekele, 2018). In the present study, out of 15, 5 foals were less than 1yr of age and had impaction (n=2) and fecalith in left ventral or small colon (n=3).

Out of 15 equines (5 Thoroughbred, 9 Marwari and one mule), 5 horses (3 Thoroughbred and 2 Marwari) died/euthanized during hospitalization. Thoroughbred horses were found more sensitive to colic, may be because of having specific acute lesion rather than the non-specific impaction/Fecalith. Thoroughbred peri-parturient mares have been reported to be genetically related to large colon volvulus (Peterson et al., 2019).

Average duration of presentation for survivors was more than the non-survivors and was inversely related to survivability. In this study, out of 3 equines having strangulating lesions, (one with volvulus had colic <12 hrs and two had for >18 hrs) only one survived. It is emphasized that early referral of equine with strangulating lesions (Hackett et al., 2015) may improve the survival outcome. There was no linear relationship between the severity of pain and the type of lesion. All equines with strangulating lesions had severe pain and abdominal distension and were presented recumbent, but a few with fecalith, impaction or foreign body also showed severe pain.

Table 1: Survivability based on various parameters.

Feeding history (Table 1)
Thoroughbred equines (n=5) were fed grams, oats, wheat bran, barley and berseem. In these, only one had impaction which survived. However, other 9 young/adult equines diagnosed with non-strangulating colic had the feeding history of wheat straw along with green fodder and wheat bran. The survival for wheat straw fed equines was more than non-wheat straw fed, indicating that wheat straw predisposes to chronic impactive colic with favourable surgical prognosis. In contrary to literature, de-worming and change in diet was not found correlating with the onset of colic in the current study (Bihonegn and Bekele, 2018).

One horse with left ventral colon fecalith had history of diarrhoea and it survived the surgery. Two equines had the history of previous colic, of which one had passed fecalith 4 days back and recovered once, with diarrhea and re-occurrence of colic (SC strangulation, non-survivor), while the other was operated 8 months back for foreign body (this time sand colic, survivor). Diarrhoea is 10.8 times more likely to develop at initial examination as compared to horses with large colon impaction (Frederico et al., 2006).
Physical parameters (Table 1)
Auscultation for borborygmi and nasogastric intubation was not possible in 2 and 5 horses, respectively, due to severe pain. Pre-surgery absence of borborygmi was related to poor prognosis compared to hypomotile borborygmi (Southwood, 2013). One equine had nasogastric reflux of >5L (small intestine ileus) related to cranial GIT lesion (Cook and Hassel, 2014).

On abdominocentesis, the cloudy fluid was found associated with small colon strangulation (euthanized), serosanguinous with volvulus (survived) and small intestine ileus (euthanized), straw-coloured with fecalith or sand colic (all survived) and no fluid with fecalith or impaction (80% survival). As compared to serum, peritoneal fluid is better indicator of abdominal organs pathology (De Heer et al., 2002, Southwood, 2013; Shearer et al., 2017).

Rectal examination was possible in 6 equines with gas filled intestinal loops in 2, associated with fecalith and foreign body. Large colon impaction was felt per-rectally in one equine (Cook and Hassel, 2014).
Pre-surgery clinical parameters (Table 2 and 3)
There was no significant difference in the HR and rectal temperature of survivors and non-survivors and between those with strangulating or non-strangulating lesions. Tachycardia in non-survivors is indicative of deteriorating cardiovascular function and hypovolemia due to dehydration (Southwood 2013, Hackett et al., 2015). Rectal temperature had been reported to be normal in colicky horses unless if colic is acute or sand colic (Bihonegn and Bekele, 2018). Similarly, no significant difference was recorded in the average RR of survivors and non-survivors but, it was significantly high for equines with strangulating lesion compared to non-strangulating, which could be related to pain (Southwood, 2013).

All the non-survivors and those with strangulating colic had CRT more than 3 seconds. But, out of 10 survivors, in 4, the CRT was > 3 seconds (Stephan et al., 2004; Krueger et al., 2014). Most of the equines (n=8) had congested mucous membrane (5 survivors), followed by injected (n=3, strangulating lesion, one survivor) (Stephan et al., 2004), mildly congested and normal (n=2 each, all survivors).

Table 2: Per cent change in the clinical parameters pre (n=15) and postoperatively [2=12, day 3=11 or 10)].

Table 3: Pre-surgical comparative values of clinical and hemato-biochemical parameters in all operated equines, survivors, non-survivors, strangulating and non-strangulating lesions. (Normal reference values have been created Merck Manual 2016, Southwood, 2013, De Heer et al, 2002 and Kilcoyne et al, 2018).

Pre-surgery haematological parameters (Table 3) (n=14), excluding the one presented in night for RDD and euthanized)
No statistically significant difference was found between the TLC and platelets values of survivors and non-survivors and those having strangulating and non-strangulating colic. Similarly, the Hb, neutrophil, lymphocyte count and PCV% values of survivors and non-survivors were non-significantly different; however, these were significantly higher in equines with strangulating compared to non-strangulating lesions. Dehydration associated haemo-concentration had been reported as a possible reason for increased  hemoglobin level in non-survivors (Ihler et al., 2009). Increased PCV had been reported as poor prognostic indicator in large colon volvulus cases (Hackett et al., 2015) and small intestinal ileus (Southwood, 2013). Approximately, 30% equines operated for colic had shift to left indicating severe overwhelming inflammation, clinically signifying sepsis (Southwood, 2013).
Pre-surgical biochemistry (Table 2 and 3)
A. Serum biochemistry
There was non-significant difference in the serum lactate, total protein, AKP, sodium, potassium, chloride and calcium values of survivors and non-survivors and between the equines with strangulating and non-strangulating colic. Serum lactate was within the normal range i.e. <2 mmol/L in 3 equines (2 having fecalith and one with repeat surgery and having sand colic). Out of 4 equines with non-strangulating colic having marginal hypoprotenemia, 3 survived. Elevated serum lactate concentration >3mmol/L was reported indicator of hypoperfusion and ischemia (Cook and Hassel, 2014) leading to shock and an elevation of >7mmol/L as a strong negative prognostic indicator for colic (Southwood, 2013). Pre-surgery total protein assessment is considered important for assessing outcome (Sheats et al., 2010).

All 5 equines (with non-strangulating lesion) having creatine kinase within the normal range, survived. Mean creatine kinase of non-survivor equines was significantly high compared to survivors, which is an indicator of intestinal ischemia and poor prognosis (Krueger et al., 2014).

Mean glucose of non-survivors and with strangulating colic was significantly high as compared to survivors and non-strangulating colic. Serum glucose (r=-0.782**, p=0.001) and creatine kinase (r=-0.677**, p=0.008) had moderate negative but significant correlation with the survivability in colicky equine. A marked and persistent increase in serum glucose of colicky equines is a negative prognostic indicator suggesting insulin resistance due to possible sepsis leading to increased gluconeogenesis through epinephrine or cortisol release (Southwood, 2013).
B. Peritoneal biochemistry
There was non-significant difference in the peritoneal total protein concentration of survivors and non-survivors, while, it was significantly low in strangulating compared to non-strangulating lesions (De Heer et al., 2002).

The peritoneal fluid lactate and serum lactate ratios of >2.0 along with sero-sanguinous peritoneal fluid had been correlated with strangulating lesions (Shearer et al., 2018, Henderson, 2013). However, in the present study, 4 equines had ratio >2, of which 3 had non-strangulating lesion. There was non-significant difference in the peritoneal lactate and creatine kinase values of survivors and non-survivors and between the equines with strangulating and non-strangulating colic. However, elevated level of peritoneal CK is reported better indicator of strangulating lesions than peritoneal lactate (Kilcoyne et al., 2018).
Comparative Pre-Surgery and Post Surgery Evaluation (n=12) (Table 2, 4)
1. Clinical parameters
No equine was recumbent after surgery and the activeness increased with follow up days except for the 2 equines which died on 2nd and 3rd day. Mucous membranes became normal within 3 days of surgery along with reduction in HR and RR (Southwood, 2013). Survivors showed reduced CRT on follow up days whereas in equines died or euthanized CRT remained >3sec.
2. Hematological Parameters
There was a non-significant reduction in haemoglobin and TLC count on the day 1 of surgery which could be due to fluid therapy and general anesthesia. But clinically these equines were normal and survived on long term also. Serial blood monitoring is reported to be of clinical significance to determine toxic changes in neutrophils, which are considered as poor prognostic indicators (Southwood, 2013). The PCV was seen to increase significantly with days of surgery in most of the equines. 
3. Serum Biochemistry
Pre-surgery serum lactate level was recorded reducing significantly with days of surgery. The one equine which was euthanized on day 3, had persistently elevated serum lactate. Every 1mmol/L increase in post-operative serum lactate had been associated with a decrease in survivability by 29% (Henderson, 2013). A significant reduction in the serum total protein was recorded from pre-surgery to day 1. Hypoproteinaemia had been reported as a frequent complication in large colon volvulus postoperatively (Sheats et al., 2010).

Creatine kinase was recorded to be significantly increased on day 1 compared to pre-surgery which might be due to muscle trauma during surgery (Carvalho Filho et al., 2019). The serum AKP and potassium was seen to be increasing significantly with days of surgery; however, sodium and glucose were significantly decreasing. On day 1, the serum chloride showed a significant rise compared to pre-surgery (but mean still within the normal limits), but by day 3, it was within the normal range for all equines. Significant decrease in the serum calcium level as was recorded on day 1 and day 2 of surgery when compared to pre-surgery values.
4. Peritoneal Biochemistry
On day 1 post-surgery, the peritoneal lactate was elevated, non-significantly, but later decreased on day 2, but was still more than the normal range. The peritoneal TP and CK were recorded to be significantly low on follow up days.

Table 4: Change in hematological and biochemical values in follow up days compared to pre-surgery (n=12 equines) (Normal reference values have been created Merck Manual 2016, Southwood, 2013, De Heer et al, 2002 and Kilcoyne et al, 2018).

Ultrasonographic findings of equines operated for colic surgery
The pre-operative ultrasound was done in 4 equines (as rest were non-cooperative due to pain). Sand was seen as bright and hyperechoic in ventral large colon on USG (Fig 1). Free peritoneal fluid was seen in one equine (2m old foal) with fecalith (Fig 2). Fluid filled dilated intestines were seen in all the equines but good peristaltic motility was seen in only foal of 2month. In one equine with impaction, whirling motility was seen and it died 3 days after surgery. Sand accumulation had been reported to appear brighter and more hyperechoic in ventral region of large colon (Klohnen, 2012, Farooq et al., 2020). FLASH ultrasonography had been reported as a quick and efficient tool to diagnose lesion in colic (Busoni et al., 2011). But, in the present study, it was observed that ultrasonography cannot be applied as a prognostic assessment aid as majority of the colicky equines are uncooperative due to acute pain.

Post-surgery, day 3 USG was done in 10 equines. The equine (with impaction) that died on day 3, had gas dilated cecum, whirling motility in intestines and lot of free fluid indicating obstruction to be still present. Another equine with small intestinal ileus and was euthanized on day 2, had no motility on day 2 USG, no free fluid in peritoneum and the loops were still distended. All other survivors showed good intestinal peristaltic motility with minimal free fluid, except in one equine where the SI loops were distended with reduced motility.

Fig 1: Ultrasonogram showing bright hyperechoic image in ventral large colon.

Fig 2: Ultrasonogram showing free fluid in abdomen.

Surgical findings as prognostic indicators (Table 1)
Pelvic flexure required drainage for emptying the contents or removal of fecalith / foreign body in 9 equines (9/15=60%). Caecum was distended and required drainage by incision in 4 cases (4/15=26.67%). Otherwise in all other cases, caecum was gas emptied using needle and suction. The reason for colic was diagnosed as impaction (n=3), fecalith (n=5, Fig 3), sand colic (2, one with ruptured intestines), foreign body (n=1, Fig 4), right dorsal displacement of large colon (n=1, Fig 5), large colon volvolus (n=1), small intestine ileus (n=1, Fig 6) and small colon strangulation (n=1).

All the equines which passed feces, recovered uneventfully. Two equines which did not pass feces and were dull on follow up days with one having gastric reflux of upto 10 liters (Ileus), died by day 2 and 3 (impaction) of surgery, respectively.

Fig 3: Photographs showing case study of a 2m old Nukra foal with left ventral colon fecalith (a), kneading of fecalith during surgery (b), pelvic flexure drainage (c), closure of pelvic flexure (d), 15 days follow up at suture removal (e), 4 month follow up at owner’s place (f and g).

Fig 4: Photographs showing case study of a 2yr old, 300kg mule with small colon foreign body (a), removing of foreign body (b), ropes and polythene passed in feces also (c), histopathology of small colon (HandE stain, 10x) showing severe necrosis along with acute inflammation (d, e), long term follow up (f).

Fig 5: Photograph showing right dorsal displacement of large colon in a 13yrs old thoroughbred mare with ischemic mesentery (euthanized during surgery).

Fig 6: Photograph showing case study of a 7 yrs old thoroughbred mare with small intestine ileus (a), small intestines enterotomy (b), post-operative nasogastric reflux of 10L (c), histopathology (H&E stain) showing chronic enteritis characterized by mild fibroplasia and mononuclear cell infiltration and congestion at 10x (d) and 40x (e).

Short and long term outcome of equine colic surgery (Table 1)
Out of 15, 12 recovered from anesthesia, while 3 were euthanized intra-operatively. However, in the due course of time of 2-3 days, one equine died and one was euthanized due to no improvement, thus making the short term survivability of 83.33% (10/12). The long term survivability was 100% (10/10), as all the equines discharged remained fit and healthy. Christophersen et al. (2014) reported surgical short term survival rate of 75%; 32% horses were euthanized pre-operatively while 27% were euthanized or died intra-operatively.
Peritoneal cytology and histological findings
Peritoneal fluid cytology was done in 9 equine and it was concluded that PMN cells alone or with lymphocytes is a better indicator of survivability. Histopathology was done in 8 equines with 10 tissue samples (pelvic flexure in 6, cecum in 2, small intestines and small colon in one each). Pelvic flexure biopsy showed variable degree of congestion in venules and inflammatory reaction in sub-mucosa and even total sloughing of mucosa and sub-mucosa, but still all these 6 equine were survivors. Equine with small intestinal ileus, recorded chronic acute inflammation with numerous PMN and some plasma cells and was euthanized on day 2. Small colon fecalith equine recorded necrosis and acute inflammation and survived the surgery. Pelvic flexure biopsy had been reported as a gold standard for intra-operative assessment of colon and short term survival (Sheats et al., 2010). Necropsy was done on 2 out of 5 equines which died during hospital stay. One was of impaction which showed peritonitis and post-operative ileus. And the other was of small colon strangulation which showed endotoxemia due to necrosis of a large segment of small colon.
1. Wheat straw feeding is predisposing for non-strangulating colic in Marwari breed but had favorable surgical prognosis, while, Thoroughbred equines, not on wheat straw are commonly presented with strangulating lesion and need early referral for favorable surgical prognosis.
2. Prolonged CRT, injected mucous membranes, absent borborygymi, high serum CK and glucose are poor prognostic indicators for colic surgery.
3. Increase in hemoglobin, neutrophils, PCV, serum glucose and decreased peritoneal total protein are indicators of strangulating lesion in colicky equine.
4. In the early post-operative period, serial monitoring of HR, RR, PCV, serum biochemistry (lactate, TP, Ca, glucose, CK) and peritoneal fluid biochemistry (lactate, TP and CK) is recommended. 
5. The colic surgery in equines bears very good short term and excellent long term outcome. 
Authors are thankful to Indian Council of Agricultural Research (ICAR), India for the financial support provided under the project, ‘All Indian Network Program on Diagnostic Imaging and Management of Surgical Affections in animals’. Authors also acknowledge Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab, India for providing necessary facilities to conduct this study.

  1. Anand, A., Singh, S.S., Saini, N.S., Mohindroo, J., Sangwan, V., Mahajan, S.K. (2017). Abdominal Hernia with and without colic in horses. Indian Veterinary Journal. 94(3): 75-77.

  2. Bihonegn, T., Bekele, F. (2018). Colic in equine: a review article. International Journal of Advanced Research in Biological Sciences. 5(5): 185-195.

  3. Busoni, V., De Busscher, V., Lopez, D., Verwilghen, D., Cassart, D. (2011). Evaluation of a protocol for fast localized abdominal sonography of horses (FLASH) admitted for colic. The Veterinary Journal. 188(1): 77-82.

  4. Carvalho Filho, W.P., Fonseca, L.A., Girardi, F.M., Bento, L.D., Souto, P.C., Orozco, A.M. (2019). Serum amyloid A and muscle activity biomarkers in horses submitted to equestrian show jumping. Pesquisa Veterinária Brasileira. 39(8): 668-671.

  5. Christophersen, M.T., Dupont, N., Berg-Sørensen, K.S., Konnerup, C., Pihl, T.H. andersen, P.H. (2014). Short-term survival and mortality rates in a retrospective study of colic in 1588 Danish horses. Acta Veterinaria Scandinavica. 56(1): 20.

  6. Cook, V.L., Hassel, D.M. (2014). Evaluation of the colic in horses: decision for referral. The Veterinary Clinics of North America. Equine Practice. 30(2): 383-398.

  7. De Heer, H.L., Parry, B.W., Grindem, C.B. (2002). Peritoneal fluid. In: Diagnostic Cytology and Hematology of the Horse. [Cowell, R.L., Tyler, R.D. (eds)], Mosby, St Louis. (pp. 127-162).

  8. Farooq, U.V., Kumar, A., Mirza, U., Ahmed, S. (2020). Sonographic evaluation of coprostatic impaction with sand and ingesta in draft equids. Indian Journal of Animal Research, DOI: 10.18805/IJAR.B-4156.

  9. Frederico, L.M., Jones, S.L., Blikslager, A.T. (2006). Predisposing factors for small colon impaction in horses and outcome of medical and surgical treatment: 44 cases (1999-2004). Journal of the American Veterinary Medical Association. 229(10): 1612-1616.

  10. Hackett, E.S., Embertson, R.M., Hopper, S.A., Woodie, J.B., Ruggles, A.J. (2015). Duration of disease influences survival to discharge of Thoroughbred mares with surgically treated large colon volvulus. Equine Veterinary Journal. 47(6): 650-654.

  11. Henderson, I.S.F. (2013). Diagnostic and prognostic use of L lactate measurement in equine practice. Equine Veterinary Education. 25(9): 468-475.

  12. Ihler, C.F., Venger, J.L., Skjerve, E. (2009). Evaluation of clinical and laboratory variables as prognostic indicators in hospitalised gastrointestinal colic horses. Acta Veterinaria Scandinavica. 45(2):109.

  13. Khosa, J.S., Anand, A., Singh, S.S., Kumar, D., Mohindroo, J. (2019a). Surgical management of right dorsal displacement of the large colon in six horses. Indian Journal of Veterinary Surgery. 40(1): 64-65.

  14. Khosa, J.S, Anand, A., Sangwan, V., Mahajan, S.K., Mohindroo, J., Singh, S.S. (2019b). Surgical management of uterine torsion through ventral celiotomy in eleven mares. Indian Journal of Animal Research. 54 (2): 244-248. DOI: 10.18805/ijar.B-3756. 

  15. Kilcoyne, I., Nieto, J.E., Dechant, J.E. (2018). Predictive value of plasma and peritoneal creatine kinase in horses with strangulating intestinal lesions. Veterinary Surgery. 48(2): 152-158.

  16. Klohnen, A. (2012). Abdominal ultrasonography in the equine patient with acute signs of colic. Association of American Equine Practitioners, 58: 11-18.

  17. Krueger, C.R., Ruple-Czerniak, A., Hackett, E.S. (2014). Evaluation of plasma muscle enzyme activity as an indicator of lesion characteristics and prognosis in horses undergoing celiotomy for acute gastrointestinal pain. BMC Veterinary Research. 10(1): 7.

  18. Manual M.V. (2016). Merck and Co. Inc. Kenilworth, NJ, USA.

  19. Peterson, J.L., Lewis, R.M., Embertson, R., Valberg, S.J., Holcombe, S.J. (2019). Preliminary heritability of complete rotation large colon volvulus in Thoroughbred broodmares. Veterinary Record. doi:10.1136/ vetrec-2018-105323. 

  20. Shearer, T.R., Norby, B., Carr, E.A. (2017). The Diagnostic utility of peritoneal fluid lactate and color in diagnosing horses with small intestinal disease. Equine Veterinary Education. 29: S8. 

  21. Shearer, T.R., Norby, B., Carr, E.A. (2018). Peritoneal fluid lactate evaluation in horses with nonstrangulating versus strangulating small intestinal disease. Journal of Equine Veterinary Science. 61: 18-21.

  22. Sheats, M.K., Cook, V.L., Jones, S.L., Blikslager, A.T., Pease, A.P. (2010). Use of ultrasound to evaluate outcome following colic surgery for equine large colon volvulus. Equine Veterinary Journal. 42(1): 47-52.

  23. Southwood, L.L. (2013). Practical Guide to Equine Colic. Wiley-Blackwell Publishers.

  24. Stephen, J.O., Corley, K.T., Johnston, J.K. and Pfeiffer, D. (2004). Factors associated with mortality and morbidity in small intestinal volvulus in horses. Veterinary Surgery. 33: 340-48. 

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