An In Vitro Investigation into the Effects of a Marine-Derived,Multimineral Supplement in Simulated Equine Stomach and Hindgut Environments

Management of the performance horse often incorporates meal feeding of highly digestible starches and reduced access to high-fiber forage. Such regimens are associated with equine gastric ulceration syndrome (EGUS) and can alter hindgut homeostasis. In-feed buffering of gastric contents and promotion of energy derivation from high-fiber forage in the hindgut are therefore desirable properties of a nutritional supplement. A marine-derived, multimineral supplement with known buffering properties containing calcium, magnesium, and short-chain fructo-oligosaccharides (scFOS) was tested under in vitro simulations of equine stomach and hindgut conditions. Six fiber:concentrate diets were incubated for 4 hours with or without the supplement at 37°C in pepsin HCl solution adjusted to pH 4.1 and 2.6. pH was measured at 1, 2, and 4 hours postincubation. Highest overall pH values were observed with the high cereal feeds; however, the supplement significantly increased (P < .001) the pH across all feeds by 0.17 and 0.19 for feeds incubated at pH 4.1 and 2.6, respectively. A gas production technique was used to measure the fermentation of four fiber:concentrate diets with and without additional supplement, using equine feces as the microbial inoculum. Addition of the supplement decreased (P < .05) the lag time and increased the initial fermentation rate, although as the incubation continued, this effect was reduced. These results demonstrate that the supplement had a significant buffering action for 4-6 hours under simulated in vitro stomach digestion conditions and also stimulated in vitro hindgut fermentation activities.     

Long-term Outcome of Standing Medial Patellar Ligament Splitting to Manage Horses Exhibiting Delayed Patellar Release: 64 Horses

A standing surgical technique for splitting the medial patellar ligament is described, and the long-term (average 4.5-years) efficacy of the procedure in horses exhibiting delayed patellar release is reported. Medical records of 64 horses that underwent a standing medial patellar ligament splitting surgery performed to treat delayed patellar release were analyzed retrospectively. Horses were sedated in standing stocks. A number 15 scalpel blade was used to percutaneously split the medial patellar ligament from just proximal to its insertion on the tibial tuberosity to its attachment on the parapatellar fibrocartilage, with the goal of inducing a localized desmitis and subsequent thickening of the ligament. Aftercare consisted of oral antibiotics, 14 days stall rest with hand walking, light exercise for 14 days, and full work at 4 weeks. Follow-up information was obtained through telephone calls to owners and/or clinical evaluation by a veterinarian. Results showed that 89% of horses benefitted from the procedure, with complete resolution in 58% of horses and improvement in 31% of horses. A total of 73% of horses were able to perform at the desired level following the procedure; 63% of horses showed signs of improvement or resolution within 30 to 60 days. Two horses had complications following the procedure: 1 horse had an incisional infection, and 1 had a medial patellar ligament rupture. This study shows that standing medial patellar ligament splitting is a successful, long-term surgical option for treatment of delayed patellar release. The procedure has few complications and allows rapid return to desired performance.     

Interaction of Grazing Muzzle Use and Grass Species on Forage Intake of Horses

The impact of horse preference and grass morphology on grazing muzzle effectiveness has not been investigated. The objective of this study was to determine the effectiveness of grazing muzzle use at reducing forage intake when horses grazed grasses with different morphology and preferences. The study was conducted in 2012 and 2013. Four horses were grazed in 2012, and three horses were grazed in 2013. Four species of perennial cool-season grasses were grazed in 2012 including Kentucky bluegrass (Poa pratensis L.), meadow fescue (Schedonorus pratensis Huds.), perennial ryegrass (Lolium perenne L.), and reed canarygrass (Phalaris arundinacea L.). In 2013, only Kentucky bluegrass and reed canarygrass were grazed because of winter kill of other species. Horses were allowed to graze a small pasture seeded with an individual species for 4 hours each day in June and August of 2012 and August and September of 2013. Horses grazed the same grass species for two consecutive days, one day with a muzzle and one day without. Before and after each grazing, a strip was mechanically harvested to determine initial and residual herbage mass. The difference was used to estimate forage intake. The effectiveness of a grazing muzzle was not affected by forage species (P ≥ .05). Use of a grazing muzzle decreased the amount of forage consumed by an average of 30% compared with not using a grazing muzzle (P < .0001). Results will aid horse owners and professionals in estimating forage intake of muzzled horses on pasture.     

Acupuncture Diagnosis in Equine Stifle Disease

The stifle is a large and complex joint in quadrupeds, including horses, making the diagnosis of stifle diseases a challenge for the clinician. The detection of “stifle syndrome” during acupuncture examination of the equine stifle may be useful for diagnosis of stifle diseases in horses. The aim of the present study was to describe stifle syndrome diagnosis in horses. From 2001 through 2012, 810 athletic horses involved in different disciplines were examined using the technique of acupuncture diagnosis. Stifle syndrome was suspected when the following points were reactive: the sacral point suggestive of stifle disease located at the sacral origin of the biceps femoris muscle, bladder (BL)-20, BL-21, and stomach (ST)-30, together with the three local points in the muscle groove of the posterolateral aspect of the thigh. The diagnostic protocol included radiography and/or ultrasonography in certain cases. The horses were evaluated because of reduced athletic performance, routine or prepurchase examination, hind limb lameness, refusal to jump, inappetence, upward fixation of the patella, thoracolumbar spine or sacroiliac pain, suspensory lesion, and front hoof problems, and 86 (9.4%) were diagnosed with stifle syndrome. The sacral acupuncture point suggestive of stifle syndrome correlated with BL-21, local stifle points, gall bladder (GB)-27, spleen-13, BL-23, BL-52, BL-26, and/or GB-25, ST-30, BL-54 (P < .0001), and BL-20 (P = .003). Twenty-two (25.6%) of the 86 horses with stifle syndrome underwent ultrasonography and/or radiography, and lesions were detected in 21. In conclusion, acupuncture for diagnosis of stifle disease may be considered a diagnostic method to be included in routine clinical examination of horses, and its reproducibility shall be investigated in further studies.     

The Effect of Different Physical Exercise on Plasma Leptin,Cortisol, and Some Energetic Parameters Concentrations in Purebred Arabian Horses

Leptin is a hormone that coordinates food intake, energy expenditure, and metabolic rate; it is, however, unknown how exercise influences plasma leptin concentration in horses. The aim of the study was to evaluate the exercise-induced changes in plasma leptin concentration in purebred Arabian horses competing in races and endurance rides. A total number of 26 horses (12 purebred Arabian racehorses aged 3–5 years and 14 endurance horses aged 7–14 years) were studied during performing routine physical exercise. From each horse, blood samples were collected at rest and immediately after the exercise session. Concentrations of plasma leptin, cortisol, lactic acid, uric acid, triacylglycerols, glycerol and free fatty acids were determined. Exercise-induced increase in cortisol and free fatty acid values were higher in endurance horses than in racehorses. Neither endurance nor race exercises influenced the plasma leptin concentration. Further research is needed to elucidate the effects of different types of exercise on leptin synthesis and secretion in horses.     

Efficacy of an Extract of Blue-Green Algae in Amelioration of Lameness Caused by Degenerative Joint Disease in the Horse

Degenerative joint disease (DJD) or osteoarthritis in the equine is largely a result of biomechanical stressors that result in inflammation within the joint, which with continual exposure, leads to progressive degeneration. A myriad of therapies are available for treatment of horses with DJD including nonsteroidal anti-inflammatory drugs, corticosteroids, physiological modifiers, and biological therapies. C-phycocyanin, a protein-bound pigment found in blue-green algae, has been shown to have anti-inflammatory and antioxidant properties and is available as a diet supplement in people, dogs, and horses. Forty-one horses with naturally occurring lameness as a result of DJD were selected for this study. In a blinded study, horses were randomly assigned to either the commercial or placebo product that was fed once daily for 12 months. At selected time points, lameness evaluation was performed through objective gait analysis. Previous medical records for management of lameness were reviewed for all enrolled horses. No statistically significant differences existed within or between the two groups when gait was evaluated objectively nor within individual horses between time points. Review of medical records found that five treated horses had a decreased in frequency of intra-articular injection of corticosteroids. Although this study did not find statistically significant improvement of lameness with oral daily supplementation of C-phycocyanin in equine athletes, there appeared to be a trend of improvement in lameness during the loading period and a decrease in frequency of administration of intra-articular corticosteroids. Further investigations using a higher dose seem warranted.     

The Feeding Practices and Estimated Workload in a Cohort of New Zealand Competition Horses

Data on the feeding, management, and training schedules during the week before the competition were collected via a face-to-face survey of riders competing in dressage, show jumping, or eventing at 1* and 3* level competitions. Data were collected using a pro forma recording sheet, and measurements of horse height, weight, and body condition score (BCS) were also obtained. A total of 158 of 582 riders (and horses) were surveyed, providing a response rate of 27%. The mean height, weight, and median BCS of the horses were 162 ± 1 cm, 533 ± 5 kg, and 6 (interquartile range [IQR], 5–7), respectively. The majority of horses were at pasture, most (68%, 107 of 158) 24 hr/d and fed supplementary feed either once (42%, 67 of 158) or twice daily (54%, 86 of 158). The supplementary feed was predominately a commercial premix feed (90%, 142 of 157) with additional alfalfa chaff or ensiled chopped alfalfa. The horses were offered approximately 60 MJ digestible energy (DE)/d (33–86 MJ DE/d) from supplementary feed. The horses worked for a median of 6 d/wk (IQR, 5–6 d/wk) with one rest day. The median total time trained during the week was 200 minutes (135–265 minutes), which consisted of eight separate training activities. There was no difference in time spent on different activities between the disciplines. Individual training activities were 30–40 minutes, and the median number of competitions per month was 2 (IQR, 2–3). Training workload and pattern of work were similar to reports from other countries, with the exception that many riders regularly added a “hack out” after training.     

Long-Term Follow-up of Superficial Digital Flexor Tendonitis Treated by a Single Intralesional Injection of a ReGeneraTing Agent in 51 Horses

ReGeneraTing Agents (RGTA) are nanopolysaccharides engineered to mimic heparan sulfates and have been shown to stimulate tissue repair and healing (skin, cornea, gingival, and muscle) in several animal models of injury and in human medicine. A preliminary study, monocentric and uncontrolled, was conducted to evaluate the efficacy of a dedicated RGTA (named Equitend) in improving the healing quality of the injured tendon after a single and ultrasound-guided intralesional injection. Improvement of ultrasonographic appearance of tendinous or ligamentous lesion was documented at least over 4 months in Equitend-treated horses and was further supported by another study on superficial digital flexor tendonitis, in 51 horses (16 French Standardbred trotters (ST), 13 Thoroughbreds (TB), and 22 eventers). Long-term follow-up of these horses showed high rates of return to racing, with 95% of eventers, 87.5% of French ST, and 77% of TB. The mean duration before the first race or competition was 6.6 and 7.4 months for ST and eventers, respectively. The group of 16 treated ST was then compared with a matched control group, showing that the Equitend-treated group was able to return to a higher level of earning after lesion (74% vs. 15% in the control group). Furthermore, the Equitend-treated group was back in racing 2.4 months earlier than the control group.     

Erythrocyte Osmotic Fragility and Hematological Responses of Horses Administered Ascorbic Acid and Exposed to Road Transportation

The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties.     

A Controlled Safety Study of Elevated Dosages of Trimethoprim Plus Sulfadiazine in Mature Horses

A novel, proprietary, oral suspension of trimethoprim plus sulfadiazine (TMP/SDZ) had no serious adverse effects on clinical, laboratory, or pathologic parameters of mature horses when administered at up to five times the intended combined dosage of 24 mg/kg twice daily for 30 consecutive days. Loose feces was the most common observation that was likely related to TMP/SDZ treatment, and the incidence of loose feces was greater in groups treated with higher dosages of TMP/SDZ. However, all episodes were self-limiting, and no horses were treated for loose feces.