Effect of a blend of magnesium oxide on Equine Squamous Gastric Disease in young trotter horses under training.

BACKGROUND: Equine squamous gastric disease (ESGD), as part of the equine gastric ulcer syndrome (EGUS), are common in racing horses. The use of buffering feed supplements to treat and/or prevent gastric ulcers is an option to control this condition. OBJECTIVE: The purpose of this study was to evaluate the effect of a 30-day supplementation with a blend of magnesium oxide (MgO) on ESGD scores in trotters under training. METHODS: Forty-two young trotters were submitted to a gastroscopic evaluation to assess their ESGD score and were randomly assigned in a group supplemented with MgO or in a control group. After 30 days, a second evaluation by gastroscopy was performed. The effect of the MgO supplementation was assessed by comparing the evolution of the ESGD score in supplemented and control groups between day 0 and day 30. RESULTS: The results confirm the high prevalence of EGUS in young Trotters. The supplementation significantly decreased the ESGD scoring in the supplemented group whereas the control group remain unchanged. CONCLUSION: The oral MgO supplementation was efficient to control ESGD in the population studied.

Efficacy of the oral supplement, Equine Omega Complete, for the prevention of gastric ulcers and alpha-tocopherol supplementation in horses.

BACKGROUND: Omega-3 fatty acid and alpha-tocopherol supplementation reduces gastric ulcer formation in humans and rodents; however, efficacy of prevention in horses is unknown. Equine Omega Complete (EOC) is an oral supplement containing omega-3 fatty acids and alpha-tocopherol. HYPOTHESIS/OBJECTIVE: Determine if EOC supplementation prevents gastric ulcers and increases serum alpha-tocopherol concentrations in healthy horses. ANIMALS: Nine thoroughbred geldings; 5-13 years old. METHODS: Prospective randomized block design, repeated in crossover model. Horses were administered EOC, omeprazole, or water PO for 28 days. Horses underwent an established gastric ulcer induction protocol from days 21-28 via intermittent feed deprivation. Gastroscopies were performed on days 0, 21, and 28. Serum alpha-tocopherol concentrations were measured on days 0 and 28. The effects of treatment and time on ulcer grades were assessed with ordinal logistic regression, with significance at P-value <.05. RESULTS: Ulcer grades increased during ulcer induction in control and EOC but not omeprazole groups (P = .02). Grades increased in EOC-treated horses after ulcer induction from a median of 1 [95% confidence interval 0-2.5] (day 0) to 2.5 [1.5-3.5] (day 28) and were similar to the control group (P = .54). Serum alpha-tocopherol increased in EOC-treated horses from day 0 to day 28 (mean 2.2 ± 0.43 µg/mL to 2.96 ± 0.89 µg/mL; P < .001) with high individual variation; this increase was not different from omeprazole or control groups. CONCLUSION AND CLINICAL IMPORTANCE: Supplementation with EOC for 28 days did not prevent gastric ulcer formation nor increase alpha-tocopherol concentrations relative to the control group.

Integrative Medicine in Equine Practice.

Integrative medicine is based on a model of being proactive and promoting health and wellness, rather than being reactive and solely focusing on episodic disease processes. Integrative medicine incorporates a holistic approach to clinical practice that encourages owner involvement with a focus on individualized care, maintained wellness, optimized performance, and disease prevention. Health promotion and preventative care require a different set of clinical skills and perspectives than is typically provided by a traditional veterinary education. Productive interprofessional collaborations are an essential component to the effective delivery of integrative medicine services.

Long-chain polyunsaturated fatty acid supplementation increases levels in red blood cells and reduces the prevalence and severity of squamous gastric ulcers in exercised Thoroughbreds.

OBJECTIVE: To assess the relationship between plasma and RBC fatty acid composition and incidence and severity of squamous gastric ulcers when altered by short-chain (SC) or long-chain (LC) polyunsaturated fatty acid (PUFA) supplementation. ANIMALS: 13 fit Thoroughbred horses in training. PROCEDURES: Horses were evaluated by gastroscopy for squamous ulcer score, gastric pH, and blood fatty acid composition prior to supplementation (UNSUPP) and after 3 months of supplementation with a corn-flax oil blend of alpha-linolenic acid and linoleic acid (SC-PUFA) or a gamma-linolenic acid (GLA)-fish oil blend of GLA, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA; LC-PUFA) in a crossover design. Prior to gastroscopy and blood collection, horses performed a 4,600-m standardized exercise test on the racetrack as a stressor. RESULTS: Three months of supplementation with LC-PUFAs increased RBC levels of GLA, dihomo-gamma-linolenic acid (DGLA), arachidonic acid (AA), EPA, and DHA, and reduced severe ulcer prevalence (38% UNSUPP vs 8% LC-PUFA with a severe ulcer score of grade 3 to 4). Short-chain PUFA supplementation did not effectively elevate RBC GLA, DGLA, AA, EPA, or DHA and severe ulcer incidence was not different (38% UNSUPP vs 23% SC-PUFA with a severe ulcer score of grade 3 to 4). Lower levels of RBC GLA, DGLA, AA, and EPA correlated with severe squamous gastric ulceration (grade 3 to 4). CLINICAL RELEVANCE: Equine gastric ulcer syndrome is prevalent in high-performance horses and is a concern to owners and trainers. Long-chain PUFA supplementation increased levels of GLA, DGLA, AA, EPA, and DHA, unlike SC-PUFA supplementation, and was associated positively with prevention or resolution of severe squamous gastric ulceration. Further studies are needed to evaluate different management styles and exercise intensities.

The Safety and Efficacy in Horses of Certain Nutraceuticals that Claim to Have Health Benefits.

Equine nutraceuticals are promoted as useful therapies to help optimize health and athletic performance, often without the benefit of independent research to support product efficacy and safety. This review focuses on 4 main categories of equine supplements that are frequently used as nutraceuticals: (i) supplements to support metabolic health, (ii) gastric support products, (iii) common ingredients that are included in supplements designed to support hoof health, and (iv) supplements to support joint health.

A Common Practice of Widespread Antimicrobial Use in Horse Production Promotes Multi-Drug Resistance.

The practice of prophylactic administration of a macrolide antimicrobial with rifampin (MaR) to apparently healthy foals with pulmonary lesions identified by thoracic ultrasonography (i.e., subclinically pneumonic foals) is common in the United States. The practice has been associated epidemiologically with emergence of R. equi resistant to MaR. Here, we report direct evidence of multi-drug resistance among foals treated with MaR. In silico and in vitro analysis of the fecal microbiome and resistome of 38 subclinically pneumonic foals treated with either MaR (n = 19) or gallium maltolate (GaM; n = 19) and 19 untreated controls was performed. Treatment with MaR, but not GaM, significantly decreased fecal microbiota abundance and diversity, and expanded the abundance and diversity of antimicrobial resistance genes in feces. Soil plots experimentally infected with Rhodococcus equi (R. equi) and treated with MaR selected for MaR-resistant R. equi, whereas MaR-susceptible R. equi out-competed resistant isolates in GaM-treated or untreated plots. Our results indicate that MaR use promotes multi-drug resistance in R. equi and commensals that are shed into their environment where they can persist and potentially infect or colonize horses and other animals.

Contracting for care - the construction of the farrier role in supporting horse owners to prevent laminitis.

BACKGROUND: Emerging research highlights how, due to demographic changes in horse owner populations in Western societies, complex owner-horse relationships are leading to inappropriate horse care, including overnutrition, which in turn can lead to laminitis. Farriers, due to their regular visits, may be in a position to support owners in dealing with this problem. OBJECTIVES: This study explored whether UK farriers have a role in working with horse owners to support horse welfare and prevent laminitis. STUDY DESIGN: Grounded theory analysis, a qualitative methodology. METHODS: Semi-structured interviews were conducted with 12 farriers and 11 horse owners. The interviews were transcribed verbatim and systematically analysed, using an inductive coding approach. RESULTS: The analysis of the farrier and horse owner interview data revealed farriers and horse owners undertake a contracting process leading to either a task-focussed or holistic care-focussed approach. Either approach can be satisfactory, but the evidence from this study suggests that when horses are at risk of laminitis, a task-focussed approach misses important opportunities to prevent it. MAIN LIMITATIONS: This analysis, based on a small sample of participants, was not able to identify the frequency of farriers or horse owners orientating towards different approaches in a way that can be generalised to a wider population. However, the power of grounded theory lies in its inductive design to develop new theory, which can be subsequently tested. CONCLUSIONS: Farriers are in a perfect position to support horse owners to prevent laminitis through providing feedback, guidance and advice. However, not all farriers adopt this role and it is not necessary in all contexts. The evidence presented in this study has implications for equine veterinarians and welfare officers in educating horse owners about the value of holistic care-focussed farriery.

Advanced nutritional and stem cells approaches to prevent equine metabolic syndrome.

Horses metabolic disorders have become an important problem of modern veterinary medicine. Pathological obesity, insulin resistance and predisposition toward laminitis are associated with Equine Metabolic Syndrome (EMS). Based on pathogenesis of EMS, dietary and cell therapy management may significantly reduce development of this disorder. Special attention has been paid to the diet supplementation with highly bioavailable minerals and mesenchymal stem cells (MSC) which increase insulin sensitivity. In nutrition, there is a great interests in natural algae enriched via biosorption process with micro- and macroelements. In the case of cellular therapy, metabolic condition of engrafted cells may be crucial for the effectiveness of the therapy. Although, recent studies indicated on MSC deterioration in EMS individuals. Here, we described the combined nutritional and stem cells therapy for the EMS treatment. Moreover, we specified in details how EMS affects the adipose-derived stem cells (ASC) population. Presented here, combined kind of therapy- an innovative and cutting edge approach of metabolic disorders treatment may become a new gold standard in personalized veterinary medicine.

Evaluation of conjugated linoleic acid supplementation on markers of joint inflammation and cartilage metabolism in young horses challenged with lipopolysaccharide.

Seventeen yearling Quarter Horses were used in a randomized complete block design for a 56-d trial to determine ability of dietary CLA to mitigate joint inflammation and alter cartilage turnover following an inflammatory insult. Horses were blocked by age, sex, and BW, and randomly assigned to dietary treatments consisting of commercial concentrate offered at 1% BW (as-fed) supplemented with either 1% soybean oil (CON; n = 6), 0.5% soybean oil and 0.5% CLA (LOW; n = 5; 55% purity; Lutalin, BASF Corp., Florham Park, NJ), or 1% CLA (HIGH; n = 6) top-dressed daily. Horses were fed individually every 12 h and offered 1% BW (as-fed) coastal bermudagrass (Cynodon dactylon) hay daily. This study was performed in 2 phases: phase I (d 0 to d 41) determined incorporation of CLA into plasma and synovial fluid; phase II (d 42 to d 56) evaluated potential of CLA to mitigate intra-articular inflammation and alter cartilage metabolism. Blood and synovial fluid were collected at 7- and 14-d intervals, respectively, to determine fatty acid concentrations. On d 42, carpal joints within each horse were randomly assigned to receive intra-articular injections of 0.5 ng lipopolysaccharide (LPS) derived from Escherichia coli 055:B5 or sterile lactated Ringer's solution. Synovial fluid samples were obtained at preinjection h 0 and 6, 12, 24, 168, and 336 h postinjection, and analyzed for prostaglandin E2 (PGE2), carboxypeptide of type II collagen (CPII), and collagenase cleavage neopeptide (C2C). Data were analyzed using PROC MIXED procedure of SAS. Horses receiving the CON diet had undetectable levels of CLA for the duration of the study. A quadratic dose response was observed in concentrations of CLA in plasma and synovial fluid (P < 0.01). A negative quadratic dose response was observed for plasma arachidonic acid (20:4) with a reduction in concentration to d 14 in HIGH horses (P = 0.04). Synovial fluid 20:4 tended to decrease in horses receiving the HIGH diet (P = 0.06). Post LPS injection, synovial PGE2 was not affected by dietary treatment (P = 0.15). Synovial C2C was lower in HIGH horses (P = 0.05), and synovial CPII tended to be greater in LOW horses than HIGH and CON horses (P = 0.10). In conclusion, dietary CLA incorporated into plasma and synovial fluid prior to LPS challenge. Dietary CLA did not influence inflammation; however, there was a reduction in cartilage degradation and an increase in cartilage regeneration.

Effects of pre-shipping enrofloxacin administration on fever and blood properties in adult Thoroughbred racehorses transported a long distance.

To evaluate the effects of single-dose enrofloxacin (ERFX) on fever and blood properties in 68 Thoroughbred racehorses after long-distance transportation, horses were assigned to receive ERFX (5 mg/kg, IV; ERFX group; n=52) or saline (0.9% NaCl) solution (50 ml, IV; control group; n=16) ≤1 hr before transportation. Horses were transported 1,122 km using commercial vans over the course of approximately 21 hr. Clinical examinations and hematologic analyses were performed before and after transportation. Rectal temperatures, white blood cell counts and serum amyloid A concentration of ERFX group were significantly lower than control group (P<0.01, P<0.01 and P<0.05, respectively). In conclusion, these results show ERFX administration just before transportation is effective at preventing transportation-associated fever in adult Thoroughbred racehorses.

The preventive effects of two nutraceuticals on experimentally induced acute synovitis.

BACKGROUND: Nutraceuticals are often used in the management of equine osteoarthritis, but scientific evidence of their efficacy is lacking. OBJECTIVES: To study the preventive effects of two new nutraceuticals after the experimental induction of synovitis in comparison with positive and negative control treatments. STUDY DESIGN: Blinded, controlled, randomised experiment. METHODS: Twenty-four healthy Standardbred horses were randomly allocated to supplement AT (multi-ingredient, 28 days), supplement HP (collagen hydrolysate, 60 days), meloxicam (4 days) or placebo (60 days). Synovitis was induced in the right intercarpal joint by intra-articular injection of 0.5 ng lipopolysaccharide (LPS) of Escherichia coli while treatments were continued. Blood and synovial fluid were sampled before treatment, immediately prior to LPS injection, and at 8, 24 and 48 h post-injection. Synovial fluid samples were analysed for total nucleated cell count (TNCC), total protein (TP) and selected biomarkers (prostaglandin E2 [PGE2 ], interleukin-6 [IL-6], glycosaminoglycans [GAGs], type II collagen synthesis [CPII], matrix metalloproteinase [MMP]). Lameness was scored by visual examination and pressure plate analysis immediately prior to LPS injection, and at 8, 24 and 48 h post-injection. Clinical examinations were performed before treatment, immediately prior to LPS injection, at 2, 4 and 6 h post-injection, and then twice per day during the test period. RESULTS: Before treatment and intra-articular challenge, there were no statistically significant differences among the treatment groups for any of the parameters. After intra-articular challenge, the placebo group showed significantly higher synovial fluid TP, TNCC and PGE2 compared with the meloxicam group, although the model did not induce a relevant amount of lameness. Both nutraceuticals resulted in significantly lower synovial fluid TP, TNCC and PGE2 compared with placebo. No statistical differences in IL-6, GAGs, CPII or MMPs were observed among treatment groups. No adverse effects were observed. MAIN LIMITATIONS: Despite evidence of synovitis, lameness was too mild to detect. CONCLUSIONS: The preventive administration of these nutraceuticals showed anti-inflammatory effects in this validated synovitis model. Therefore, further studies of their clinical applicability are warranted.

Preventive health care of Pony Club horses in rural New South Wales, Australia.

OBJECTIVE: To describe preventive health care provided to a cohort of Pony Club horses in rural New South Wales, Australia, and the associated veterinary involvement. DESIGN: Prospective longitudinal study METHODS: Observational data collected for 48 Pony Club horses using daily owner-kept diaries and monthly veterinary visits for 9-12 months. RESULTS: Frequency of healthcare events varied markedly between the horses; 54% of horses received 5 or more foot-care treatments, 69% received 1-3 anthelmintic treatments, 40% received dental care, 21% received chiropractic care; only 8% were vaccinated. Farriers and owners administered most of the health care. Veterinarians were infrequently involved, administering 2 of the 111 anthelmintic administrations and 2 of the 244 foot-care treatments. No annual health checks or prepurchase examinations were recorded. All dental care was provided by non-veterinary dentists. Horse turnover appeared quick, with 54% of horses acquired within the previous 12 months. CONCLUSION: The majority of preventive health care was provided by farriers and the owners themselves. The type and frequency of healthcare events varied markedly and most commonly involved foot care and anthelmintic administration. The reasons for the lack of veterinary involvement are unclear. Veterinarians engaging with Pony Club families in a preventive context would likely bring health benefits to this population of horses. This may require adaptation of existing veterinary services to meet the demands of this unique population of horses and young riders. Furthermore, epidemiological studies are required to describe the effects of various preventive healthcare interventions on subsequent and long-term horse health.

Effects of two alfalfa preparations with different particle sizes on the gastric mucosa in weanlings: alfalfa chaff versus alfalfa pellets.

BACKGROUND: Feeding alfalfa hay is often recommended for its buffering components, like protein and calcium, to prevent lesions of the gastric mucosa in horses. Until now, there has been no information regarding the influence of alfalfa particle size on the gastric mucosa. The aim of this study was to investigate the effects of feeding two alfalfa preparations with different particle sizes (alfalfa chaff vs alfalfa pellets) in comparison with grass hay on the gastric mucosa in weanling horses. We hypothesized that feeding a high proportion of fine alfalfa particles would negatively impact gastric mucosa and that feeding long alfalfa chaff would improve gastric mucosal health in weanlings. RESULTS: Before weaning, the prevalence of gastric mucosa lesions (one or more lesions considering all locations in the stomach) was 84.3 %; at 14 days after weaning, it was almost 100 %. Before and after weaning, most of the lesions were found at the greater curvature of the squamous mucosa and at the lesser curvature. After weaning, gastric mucosal lesions at the pylorus were significantly more severe in the group fed alfalfa chaff (p = 0.002). In the other regions, no differences related to the feeding regimes were observed. CONCLUSIONS: Feeding alfalfa failed to improve gastric mucosal lesion scores in weanlings. Furthermore, foals fed alfalfa chaff had higher lesion scores at the pylorus. Alfalfa leaves contain a superior protein source and high amounts of calcium and magnesium, providing extra nutritional advantages in growing horses. At this time, either traditional grass hay rations or grass hay with alfalfa pellets can be recommended.

Activated carbons as potentially useful non-nutritive additives to prevent the effect of fumonisin B1 on sodium bentonite activity against chronic aflatoxicosis.

Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.

Effects of a docosahexaenoic acid-rich microalgae nutritional product on insulin sensitivity after prolonged dexamethasone treatment in healthy mature horses.

OBJECTIVE: To determine effects of a microalgae nutritional product on insulin sensitivity in horses. ANIMALS: 8 healthy mature horses. PROCEDURES :Horses (n = 4/group) received a basal diet without (control diet) or with docosahexaenoic acid-rich microalgae meal (150 g/d) for 49 days (day 0 = first day of diet). On day 28, an isoglycemic hyperinsulinemic clamp procedure was performed. Horses then received dexamethasone (0.04 mg/kg/d) for 21 days. On day 49, the clamp procedure was repeated. After a 60-day washout, horses received the alternate diet, and procedures were repeated. Plasma fatty acid, glucose, and insulin concentrations and glucose and insulin dynamics during the clamp procedure were measured on days 28 and 49. Two estimates of insulin sensitivity (reciprocal of the square root of the insulin concentration and the modified insulin-to-glucose ratio for ponies) were calculated. RESULTS: Baseline glucose and insulin concentrations or measures of insulin sensitivity on day 28 did not differ between horses when fed the control diet or the basal diet plus microalgae meal. On day 49 (ie, after dexamethasone administration), the microalgae meal was associated with lower baseline insulin and glucose concentrations and an improved modified insulin-to-glucose ratio for ponies, compared with results for the control diet. CONCLUSIONS AND CLINICAL RELEVANCE: Although the microalgae meal had no effect on clamp variables following dexamethasone treatment, it was associated with improved plasma glucose and insulin concentrations and insulin sensitivity estimates. A role for microalgae in the nutritional management of insulin-resistant horses warrants investigation.

Effects of pre-shipping marbofloxacin administration on fever and blood properties in healthy Thoroughbreds transported a long distance.

The present study evaluated the effects of single-dose marbofloxacin in protecting horses against fever associated with transportation using 48 healthy Thoroughbreds. All horses were premedicated with interferon-α (0.5 U/kg, sublingually, every 24 hr) for 2 days before transportation and on the day of transportation. Horses were randomly assigned to receive marbofloxacin (2 mg/kg, IV, once; MRFX group), enrofloxacin (5 mg/kg, IV, once; ERFX group) or saline (0.9% NaCl) solution (10 ml, IV, once; control group) ≤1 hr before being transportation. Each group contained 16 horses (8 males, 8 females). Horses were transported 1,210 km using commercial vans over the course of approximately 26 hr. Clinical examinations and hematologic analyses were performed on all horses both before and after transportation. Post-transportation neutrophil to lymphocyte ratios were significantly lower in horses in the MRFX group compared with the control horses. The serum amyloid A levels were significantly lower in horses in the MRFX group and ERFX group compared with the control horses. Regarding the post-transportation rectal temperatures, fever was detected in 0 horses and 1 horse in the MRFX and ERFX groups, respectively, whereas fevers exceeding 39.1°C were detected in 2 horses in the control group. Additionally, the number of essential post-transportation treatments provided by veterinarians was reduced 3-fold in the MRFX and ERFX groups compared with the saline group. MRFX provided ERFX-like protection against fever associated with long-distance transportation, yielding significantly better protection than saline. Administration of MRFX just before transportation deserves a further study for efficacy in preventing horse fever associated with transportation.

Survey of the therapeutic approach and efficacy of pentosan polysulfate for the prevention and treatment of equine osteoarthritis in veterinary practice in Australia.

OBJECTIVE: To survey veterinary practitioners in Australia on how they administer pentosan polysulfate (PPS) to horses and their perceptions of the efficacy of PPS for: the prevention and treatment of osteoarthritis (OA), the treatment of OA when PPS is combined with other drugs, and the efficacy of PPS compared with other disease-modifying osteoarthritic drugs. DESIGN: Practitioners were contacted by email, which contained a link to an online survey. RESULTS: A total of 76 responses (34.5%) to the survey were received. Respondents most commonly used PPS as prophylactic therapy prior to competition (80.3%). As a prophylactic agent, PPS was considered by 48.2% of respondents to have high efficacy. The most common dose regimen for prevention and treatment of OA was 3 mg/kg, intramuscularly, once weekly for 4 weeks followed by monthly injections. Most respondents (78%) combined PPS with other drugs for treatment of OA. Intra-articular corticosteroids and hyaluronate (HA) was the most common drug combination used with PPS. PPS was preferred as a prophylactic agent when compared with HA (88.7% vs 11.3%). For treating OA, 83% of respondents considered a combination of PPS, HA and glucosamine to be more efficacious than PPS alone. However, the most common reason not to use this combination was cost (79.1%). CONCLUSION: All respondents used PPS for prophylaxis and/or treatment of OA despite limited published scientific evidence proving its efficacy in horses. Further research is necessary to provide evidence of the clinical efficacy of PPS for the prevention and treatment of OA in horses.

How does the suppression of energy supplementation affect herbage intake, performance and parasitism in lactating saddle mares?

Agroecology opens up new perspectives for the design of sustainable farming systems by using the stimulation of natural processes to reduce the inputs needed for production. In horse farming systems, the challenge is to maximize the proportion of forages in the diet, and to develop alternatives to synthetic chemical drugs for controlling gastrointestinal nematodes. Lactating saddle mares, with high nutritional requirements, are commonly supplemented with concentrates at pasture, although the influence of energy supplementation on voluntary intake, performance and immune response against parasites has not yet been quantified. In a 4-month study, 16 lactating mares experimentally infected with cyathostome larvae either received a daily supplement of barley (60% of energy requirements for lactation) or were non-supplemented. The mares were rotationally grazed on permanent pastures over three vegetation cycles. All the mares met their energy requirements and maintained their body condition score higher than 3. In both treatments, they produced foals with a satisfying growth rate (cycle 1: 1293 g/day; cycle 2: 1029 g/day; cycle 3: 559 g/day) and conformation (according to measurements of height at withers and cannon bone width at 11 months). Parasite egg excretion by mares increased in both groups during the grazing season (from 150 to 2011 epg), independently of whether they were supplemented or not. This suggests that energy supplementation did not improve mare ability to regulate parasite burden. Under unlimited herbage conditions, grass dry matter intake by supplemented mares remained stable around 22.6 g DM/kg LW per day (i.e. 13.5 kg DM/al per day), whereas non-supplemented mares increased voluntary intake from 22.6 to 28.0 g DM/kg LW per day (13.5 to 17.2 kg DM/al per day) between mid-June and the end of August. Hence total digestible dry matter intake and net energy intake did not significantly differ between supplemented and non-supplemented mares during the second and third cycles. In conclusion, supplementing lactating mares at pasture should not be systematic because their adaptive capacities enable to increase herbage intake and ensure foal growth. Further research is needed to determine the herbage allowance threshold below which supplementation is required.

Efficacy of a pectin-lecithin complex for treatment and prevention of gastric ulcers in horses.

The objective of this study was to evaluate the effect of a commercial feed supplement containing pectin-lecithin on squamous mucosa ulceration in horses exposed to an experimental ulceration model. Five mares were treated while five mares were controls for this crossover, blinded study. The mares were fed concentrates and hay and were stabled with a two-hour turn out per day for a period of four weeks. The pectin-lecithin complex was fed for the duration of the study on the treated group. At the end of a four-week period, all mares underwent a seven-day alternating feed deprivation (week 5). The study was repeated again after a four-week washout period. Gastroscopy was performed on days 1, 28 and 35 of the study and was digitally recorded. Independent evaluation of the recordings and scoring of the lesions using the Equine Gastric Ulcer Syndrome (EGUS), severity and number scores were performed by three experienced gastroscopists. The prevalence and severity of squamous ulcers significantly increased after intermittent feed deprivation (P<0.001). No significant effect of the treatment was observed (P>0.05). In this study, the addition of a commercially available pectin-lecithin complex to the feed of horses for five weeks did not prevent or minimise the risk for gastric ulceration of the squamous mucosa.