Enucleation in equids with and without the use of an orbital suture meshwork implant: a retrospective study of 37 cases.

This retrospective study on 37 horses was conducted to assess long-term complications, scarring, cosmetic appearance and owner satisfaction of horses that underwent transpalpebral enucleation with (n=26) or without (n=11) non-absorbable sutured meshwork prosthesis between 2006 and 2013. Postoperative complications related to the surgery were wound infection, discharge and dehiscence, and no significant difference between groups was found. In one horse, the meshwork had to be removed in order to treat a chronic fistula. Horses with infection or inflammation before surgery were more likely to encounter postoperative complications, whether or not a meshwork was used. Most owners were satisfied by the surgical technique for scarring, but contrary to the present hypothesis, most horses with a meshwork implant had a poor sunken-in appearance, and 26 per cent of owners would like to attempt other techniques to improve the cosmetic result. Also, a further 44 per cent of owners would prefer a better cosmetic result if the technique does not increase complication risk or cost. Meshwork implant prosthesis after transpalpebral enucleation was safe. However, in order to achieve a better cosmetic result, further improvements of the technique will be required.

The use of maggot debridement therapy in 41 equids.

REASONS FOR PERFORMING STUDY: Maggot debridement therapy is a long-established tool to promote wound healing. OBJECTIVES: To describe and assess the results of this technique in equids with various lesions. METHODS: Retrospective analysis performed on cases in which, depending on clinical case, type, size and location of the wound, maggots were applied either in direct or indirect contact with the wound. RESULTS: Treated cases (n = 41) included horses with foot pathology (n = 9), laceration of the limbs (n = 15), other soft tissue abscesses or wounds (n = 6), fistulous withers (n = 5), other musculoskeletal infection (n = 2) and dehiscence of the linea alba (n = 4). In 5 cases, a second maggot application was necessary to reach the desired level of wound healing. In 38 cases a favourable outcome was reached in less than one week. In one individual with a sequestrum, healing was uneventful after its removal. In 2 other horses, squamous cell carcinoma and melanoma were involved in chronic infected wounds and complete healing was not achieved because of recurrence of underlying tumours. Some discomfort was recorded in 7 individuals between 24 and 72 h of treatment. CONCLUSIONS: Maggot debridement therapy can be recommended in equids for debridement and enhanced healing and its potent antibacterial action. Maggot debridement therapy is not recommended on wounds invaded with a tumour and if bone sequestration is suspected. POTENTIAL RELEVANCE: Maggot debridement therapy can be an integral part of modern wound care in equids.

Variations of plasmatic concentrations of Insulin-like Growth Factor-I in post-pubescent horses affected with developmental osteochondral lesions.

Developmental osteochondral lesions are often encountered in the equine population and are a major cause of lameness. Different growth factors that act systemically as well as locally regulate the growth of cartilage. Among them is Insulin-like Growth Factor I that has been demonstrated to promote chondrocyte growth and differentiation and that has been shown to influence cartilage repair. The aims of this study were to investigate differences in circulating plasma levels of Insulin-like Growth Factor-I in post-pubescent horses affected with developmental osteochondral lesions compared to unaffected ones. Significantly higher values of circulating Insulin-like Growth Factor-I levels were found in the affected group (n = 82) compared to controls (n = 86). This result may still reflect an earlier imbalance in IGF-I levels from horses with developmental osteochondral lesions considering the aetiopathological link which has been made between IGF-I and the occurrence of osteochondrosis. However, other studies have shown increased expression of IGF-I after cartilage damage. The higher levels found in this study could be due to a healing response of the cartilage to the damage caused by the osteochondral lesions.

Plasma concentration of insulin-like growth factor I (IGF-I) in growing Ardenner horses suffering from juvenile digital degenerative osteoarthropathy.

Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to affect the anabolism of cartilage matrix molecules. A group of 30 Ardenner horses reared under standardized conditions from weaning were evaluated periodically from 15 to 28 months of age to detect the early manifestations of the disease. At the end of this period, horses were classified in two pathological groups related to the degree of interphalangeal degenerative osteoarthropathy based on clinical and radiographic evaluations: healthy (46.7%) and pathological (53.3%) horses. Seven sequential blood samples were taken from each horse (during the evaluation period) to study the variation of IGF-I plasma concentration. We tested the variations of the IGF-I plasma concentration during growth, and the effect of sex and of pathological classes. Significant variations were observed during the research period, with a maximum value corresponding to spring and a minimum in autumn. A significant reduction of the IGF-I plasma concentration was also observed in the pathological horses (433.5 +/- 19.5 ng/ml) compared to the healthy horses (493.9 +/- 18.2 ng/ml). An alteration in the level of this growth factor could induce a disregulation of the mechanisms involved in the local control of joint and bone tissue development.

Plasma concentrations of a type II collagen-derived peptide and its nitrated form in growing Ardenner sound horses and in horses suffering from juvenile digital degenerative osteoarthropathy.

Several breeds of draft horses suffer from degenerative digital osteoarthropathy, resulting in a reduced active lifespan. A group of 30 Ardenner horses was followed, in standardized conditions, from 15 to 28 months of age to detect the early manifestations of the disease. The severity of the disease was assessed according to a personal grading system including clinical and radiographic items. Coll 2-1, a peptide of the helical region of type II collagen, and its nitrated form (Coll 2-1 NO(2)) were assayed in blood plasma collected at 452 +/- 18 days, 504 +/- 20 days, 558 +/- 18 days, 613 +/- 19 days, 675 +/- 19 days, 752 +/- 21 days and 852 +/- 19 days of age. At the end of the follow-up period, 53.3% of Ardenner horses were affected by a degenerative digital osteoarthropathy. A significant effect (p<0.05) of time, sex and pathology was observed for Coll 2-1 NO(2). Variations of Coll 2-1 were not significant except for the time effect. The elevation of Coll 2-1 NO(2) in the pathological group could indicate an inflammatory process during the growth of the affected horses, as nitration of tyrosine is mediated through reactive oxygen/nitrogen species and/or myeloperoxidase activity. Coll 2-1 NO(2) appears to be an interesting early marker of cartilage degradation and oxidation in degenerative osteoarthropathy.

A type II-collagen derived peptide and its nitrated form as new markers of inflammation and cartilage degradation in equine osteochondral lesions.

Markers of cartilage breakdown enable studying the degradation of cartilage matrix in equine joint pathologies. This study was designed to determine the levels of Coll2-1, a peptide of the triple helix of type II collagen, and Coll2-1NO(2), its nitrated form in the plasma of healthy horses (controls; n=37) and horses suffering from osteochondrosis (n=34). Clinical and arthroscopic scores were attributed reflecting the severity of lesions and were related to the plasma levels of Coll2-1 and Coll2-1NO(2). The median of Coll2-1 was significantly higher in the control group, whereas the mean of Coll2-1NO(2) showed significant elevation in the pathological group. However, the measurement means of scoring classes did not vary significantly. The markers were able to differentiate the group of horses suffering from osteochondrosis from the group of healthy horses. The elevation of Coll2-1NO(2) in the pathological group indicates an inflammation, mediated through reactive oxygen species and/or increased myeloperoxidase activity.

Retrospective study of 99 cases of bone fractures in cattle treated by external coaptation or confinement.

Between 2000 and 2003, 99 cattle with limb fractures were treated. Over 50 per cent were tibial fractures, with the femur and os calcis being the second and third most frequently affected bones. Eight of the cattle were slaughtered because of their poor prognosis, 10 were treated by stall confinement, 76 were treated by external coaptation with a Thomas splint-cast combination and three were treated with a simple or reinforced half limb cast; these 79 cattle were usually discharged immediately. One calf was treated with internal fixation, and another by amputation. Follow-up information was obtained by telephone, and the treatments were classified as either completely successful (return to previous production level), partially successful (return to lower production level) or failure. Forty (52.6 per cent) of the cattle treated with the Thomas splint-cast combination were classified as a complete success and 14 (18.4 per cent) as a partial success; the treatment failed in 19 of the cattle and three were lost to follow-up. The animals' bodyweight, age and sex, and whether the fracture was open or closed, had no significant influence on the outcome. Among the 10 cattle treated for proximal fractures by stall confinement, there were five survivors, four non-survivors and one was lost to follow-up.

Plasma concentrations of myeloperoxidase in endurance and 3-day event horses after a competition.

REASON FOR PERFORMING STUDY: In man, exercise of any type has been shown to induce neutrophil degranulation and respiratory burst activity, as well as an increase in plasma myeloperoxidase (MPO), a specific enzyme of neutrophil azurophilic granules with a strong oxidative activity. Until now, it is not known whether this is the same in horses. OBJECTIVES: To study whether degranulation of blood neutrophils may be induced by exercise by measuring the total concentration of MPO and assess the possible influence of type of competition on this exercise-induced adjustment. METHODS: Blood was sampled before, and 30 min after, the course, in 9 ponies performing the Phase D of a national 3-day event championship (CIC*), and in 7 endurance horses participating at the European endurance championship 2005. White blood cells and granulocytes, total plasma proteins, creatine phosphokinase (CK), and total MPO contents were determined from blood samples. In addition, blood was taken from all ponies and 4 of the endurance horses 5 min after completion of the course to give some idea of the intensity of exercise. RESULTS: The mean blood lactate was 15.8 +/- 5.8 mmol/l after the CIC* and 2.7 +/- 0.2 mmol/l after the 160 km course. Performing both competitions induced a significant increase in CK and MPO. After the endurance course, the number of granulocytes significantly increased. Whilst there was no significant correlation between the measurements in CIC* ponies, MPO was significantly correlated with granulocyte count (r2 = 0.776) and CK (r2 = 0.586) in endurance horses. CONCLUSIONS: Intense exercise induces an activation of blood granulocytes, with degranulation of neutrophils and release of MPO. The plasmatic MPO concentration after endurance was higher than the values reported in some inflammatory pathological conditions. POTENTIAL RELEVANCE: This phenomenon may partly contribute to the occurrence of an exercise-induced oxidative stress and to the alteration of muscular membrane permeability. Further studies should be conducted to assess the possible relationship between MPO concentration and markers of oxidative stress in performance horses.

Pancreatic injury in equine acute abdomen evaluated by plasma trypsin activity and histopathology of pancreatic tissue.

In cases of equine acute abdominal disease, where pancreatic damage is suspected, pancreatic damage can be assessed by measuring increased trypsin activity in the plasma of horses suffering intestinal obstruction and severe shock. The pancreas is particularly vulnerable to splanchnic hypoperfusion because it is a highly active tissue. In this study, 10 horses undergoing abdominal surgery for intestinal obstruction were assayed for trypsin activity on admission and, because of extensive intestinal lesions that were not amenable to surgery, euthanasia was selected; the pancreas was removed before euthanasia. Trypsin activity in the plasma of these horses was significantly higher than in healthy horses (196 ng/ml +/- 128.2 versus 28.5 ng/ml +/- 19.2; P = 0.0026). Light and transmission electron microscopy revealed slight to severe lesions of vacuolar degeneration, a few zymogen granules, dilation of the endoplasmic reticulum, and swelling of mitochondria in the exocrine pancreas. The activation of an inflammatory cascade occurring during strangulating intestinal obstruction could increase pancreatic anoxic lesions caused by severe shock and hypoperfusion in the horse. Further studies will show the significance of pancreatic lesions and the ensuing damage in equine acute intestinal obstruction and shock.

Plasma trypsin level in horses suffering from acute intestinal obstruction.

Gastrointestinal disorders in horses leading to endotoxic shock could have further consequences on other splanchnic organs such as the pancreas, as can be seen in humans suffering from septic shock. In this study, the range of enzymatically active trypsin (EAT) in healthy horses was established and is similar to the range observed in healthy humans. EAT values were determined in horses with acute abdominal crises on admission as well as during anaesthesia and in the postoperative phase. A significant increase in plasma EAT was found in 59% of the horses with surgical colic when compared to our established reference range. Significantly higher values were found in severe shock cases. When separated in groups according to the duration of colic before referral, significantly higher EAT values were observed in the non-survivor group compared to the survivor group of colics of short duration. EAT plasma values increased significantly during the postoperative phase, and were significantly higher in small intestine obstructions than in large bowel disorders. In human medicine, hypovolaemic or septic shock patients show an increase in pancreatic proteases. Splanchnic hypoperfusion during shock could lead to pancreatic damage resulting in trypsin liberation into the peritoneal space and an increase in plasma levels. Trypsin is able to activate inflammatory cascades and leucocytes and could play a role in multiple organ failure. Further studies are needed to evaluate the implications of changes in plasma trypsin in the disease process of equine acute abdomen and to demonstrate possible pancreatic damage.

Determination of a gravity and shock score for prognosis in equine surgical colic.

A retrospective study evaluated 200 surgical colic cases. A gravity score (GS) based on four clinical parameters estimating intestinal obstruction (rectal palpation, borborygmi, abdominal distension, pain) and classified into three categories was established and tested to determine if it could evaluate prognosis. A shock score (SS) based on six parameters was also attributed to each case. The overall survival rate was 54%. The statistical analysis showed a significant (P < 0.01) difference in the survival rate in the different categories of the GS, as well as in the categories of the SS. A multivariate logistic regression model showed that horses with GS 3 are 10.6 times more likely to die than those with GS 1. A model combining the two scores showed an odds ratio of 7.1 for GS 3 versus GS 1, and for SS 3 versus SS 1, the odds ratio was 7.2.

Comparison of thiopentone/guaifenesin, ketamine/guaifenesin and ketamine/midazolam for the induction of horses to be anaesthetised with isoflurane.

Forty-eight horses subjected to elective surgery were randomly assigned to three groups of 16 horses. After premedication with 0.1 mg/kg acepromazine intramuscularly and 0.6 mg/kg xylazine intravenously, anaesthesia was induced either with 2 g thiopentone in 500 ml of a 10 per cent guaifenesin solution, given intravenously at a dose of 1 ml/kg (group TG), or with 100 mg/kg guaifenesin and 2.2 mg/kg ketamine given intravenously (group KG), or with 0.06 mg/kg midazolam, and 2.2 mg/kg ketamine given intravenously (group KM). Anaesthesia was maintained with isoflurane. The mean (sd) end tidal isoflurane concentration (per cent) needed to maintain a light surgical anaesthesia (stage III, plane 2) was significantly lower in group KM (0.91 [0.03]) than in groups TG (1.11 [0.03]) and KG (1.14 [0.03]). The mean (sd) arterial pressure (mmHg) was significantly lower in group KG (67.4 [2.07]) than in groups TC (75.6 [2.23]) and KM (81.0 [2.16]). There were no significant differences in the logarithm of the heart rate, recovery time or quality of recovery between the three induction groups. However, pronounced ataxia was observed in the horses of group KM, especially after periods of anaesthesia lasting less than 75 minutes.