The Dietary Components and Feeding Management as Options to Offset Digestive Disturbances in Horses

A profiling of faecal parasites in horses in Mauritius and resistance to Fenbendazole at one horse-riding stable

Mauritius hosts a population of approximately 900 equids, but no investigations have delved into issues such as the prevalence of equine helminths, anthelmintic usage, and resistance emergence. This study aimed to devise a qualitative and quantitative profile of common helminthic intestinal parasites in equines at eight out of twenty-eight stables (272 horses, 29 % of local population) and to determine whether helminthic intestinal parasites in equines at one stable have developed resistance to Fenbendazole by quantitatively assessing pre-treatment faecal egg counts, post-treatment faecal egg counts and percentage faecal egg count reduction (%FECR). Targeted parasites included Parascaris equorum, strongyles (Cyathostomum spp. and Strongylus spp.), Fasciola hepatica, Dictyocaulus arnfieldi, Trichostrongylus axei, and Strongyloides westeri, identified based on their morphological characteristics and relative size. Results indicated a prevalence for P. equorum in 31 % and strongyles in 22 % of horses sampled. No other helminth eggs were detected in any of the samples studied. Quantitative analysis, employing the McMaster Technique for faecal egg count (FEC), revealed that 99 % and 98 % of horses sampled exhibited FEC < 200 eggs per gram (epg) for P. equorum and strongyles respectively, categorizing them as low shedders by AAEP standards. Two percent of horses were classified as moderate strongyle egg shedders (between 200 and 500 epg), and 0 % were high strongyle egg shedders (more than 500 epg). For P. equorum, 0.4 % of horses were categorized as moderate egg shedders and 0.4 % were high egg shedders. No significant correlations were discerned between FEC and stable parameters such as location and size. At one stable, fenbendazole (FBZ) was administered orally at a dosage of 5 mg/kg via stomach tube to 24 equids. Pre-treatment FEC values were compared to post-treatment FECs taken 14 days after anthelmintic administration, with the %FECR computed. Mean %FECR and adjusted mean %FECR for P. equorum were 91 % and 92 % respectively, which suggested drug efficacy. For strongyle, mean %FECR and adjusted mean %FECR were 59 % and 98 % respectively, which also seemingly supported the hypothesis of lack of resistance. Bayesian analysis however, revealed only a 63 % probability (i.e. <95 %) that true reduction exceeds 90 %. The findings suggested the presence or imminent presence of resistance to fenbendazole at this stable and emphasized the imperative for judicious anthelmintic administration coupled with a surveillance-oriented approach to mitigate resistance emergence in other stables. Furthermore, the pressing need to adopt alternative integrated control measures is emphasized, reflecting the urgency in addressing this burgeoning challenge in equine health management.

The Vital Roles of Agricultural Crop Residues and Agro-Industrial By-Products to Support Sustainable Livestock Productivity in Subtropical Regions

Sustainable livestock production is a critical component of global food security and environmental stewardship. Agricultural crop residues, such as cereal straws, stovers, and hulls, as well as agro-industrial by-products, including oilseed meals, distillery wastes, and fruit/vegetable processing residues, are generated in large quantities worldwide, and these residues can be used in the diet of the animals to reduce the feed production cost and sustainability. In this review, we found that the use of treated crop residues in the diet of animals increased the production performance without causing any side effects on their health. Additionally, we also noticed that using these crop residues also mitigates the methane production in ruminants and feed costs, particularly for harvesting the feed crops. Traditionally, these materials have often been underutilized or even disposed of improperly, leading to wastage of valuable nutrients and potential environmental pollution. By incorporating these materials into animal feed formulations, livestock producers can benefit from several key advantages. The review further discusses the challenges and considerations involved in the effective utilization of these alternative feed resources, such as variability in nutrient composition, anti-nutritional factors, and the need for appropriate preprocessing and formulation strategies. Emerging technologies and innovative approaches to optimize the integration of crop residues and by-products into sustainable livestock production systems and also reduce global warming, particularly methane, CO2 and other particles that affect the environment after burning these crop residues, are also highlighted. By synthesizing the current knowledge and exploring the multifaceted benefits, this review underscores the vital roles that agricultural crop residues and agro-industrial by-products can play in fostering the sustainability and resilience of livestock production, ultimately contributing to global food security and environmental stewardship.

Dietary Energy Sources Affect Cecal and Fecal Microbiota of Healthy Horses

Different energy sources are often used in horse diets to enhance health and performance. Understanding how diet impacts the cecal and fecal microbiota is crucial for meeting the nutritional needs of horses. High-throughput sequencing and qPCR were used to compare the fecal and cecal microbiota of five healthy horses receiving three different diets: hay diet (HAY), hay + starch and sugar (SS), and hay + fiber and oil ingredients (FO). Assessment of short-chain fatty acids, pH, and buffer capacity was also performed. The HAY diet was associated with the highest values of fecal pH; the FO and SS diets were associated with higher values of BC6 in the cecum, and the SS diet had higher BC5 values in feces (p < 0.05). HAY was associated with a lower alpha diversity in feces and with a higher abundance of Treponema, Fibrobacter, Lachnospiraceae AC2044, and Prevotellaceae UCG-003 in feces. SS was associated with a higher abundance of Desulfovibrio, the Lachnospiraceae AC2044 group, and Streptococcus in the cecum, and Streptococcus and Prevotellaceae UCG-001 in feces, while FO was associated with higher Prevotella, Prevotellaceae UCG-003, and Akkermansia in the cecum, and the Rikenellaceae RC9 gut group and Ruminococcus in feces. This study indicated that different energy sources can influence cecal and fecal microbiota composition and fecal diversity without significantly affecting fermentation processes under experimental conditions. These findings suggest that the diets studied may not pose immediate health risks; however, further research is needed to generalize these effects on gastrointestinal microbiota in broader equine populations.

The Fibre Requirements of Horses and the Consequences and Causes of Failure to Meet Them

Failure to meet the minimum forage requirement of 1.5% of the horse's bodyweight and the opportunity for foraging for a minimum of 8 h a day (not going without this opportunity longer than four to five consecutive hours) can have both physiological and behavioural consequences. To provide an energy source for horses, rations often include starch rather than fibre. This can result in health issues related to the gastrointestinal tract (GIT) in the horse. In the stomach, the main concern is equine gastric ulcer syndrome (EGUS) and, more specifically, equine squamous gastric disease (ESGD). Ulcerations are caused either by increasing acidity in the stomach (from starch ingestion and reduced saliva production) or splashing of acidic juices caused by a lack of a forage barrier prior to exercise or prolonged periods without fibrous feed intake, which allows the stomach to collapse and spread acidic gastric fluids into the upper squamous regions of the stomach. In the hindgut, starch that has escaped digestion in the small intestine causes microbial instability and increased production of volatile fatty acids (VFA) and lactic acid. This puts horses at great risk for acidosis and subsequent laminitis. Shifts in the hindgut microbiota will also affect a horse's behaviour via the gut-brain axis, as well as potentially compromise immune function. Reduced fluid intake caused by reduced saliva production can result in colic. Choosing a fibrous alternative for starch in a high-energy diet greatly reduces the risk of EGUS and acidosis and improves digestion, GIT pH, body condition, behaviour, immune functions, and performance. Providing hay can reduce crib-biting, wood-chewing, coprophagia, the consumption of bedding, aggression, and stress, and subsequently increase social bonding and affiliation with conspecifics. Adequate fibre intake is related to reduced clinical signs of EGUS, reduced reactivity, and better adaptation to weaning. Lignophagia (wood chewing) has also been observed in horses that are foraging, and this is thought to reflect low fibre content in the available forage (for example, early vegetative, lush pasture).

Effects of the Ingestion of Ripe Mangoes on the Squamous Gastric Region in the Horse

Erosions and gastric ulcers may be present in horses at any age and under different conditions of rearing and handling. In tropical regions, horses can feed on fruits rich in soluble carbohydrates, such as mangoes, but little is known about how these foods interact with their digestive systems. To test the hypothesis that the ingestion of ripe mangoes with peels could cause disturbances in the digestive processes of horses, an experiment was developed to monitor animals that had free access to ripe mangoes in their pasture areas. Horses (purebred Arabians, n = 5; ~340 kg, ~13 years) were evaluated by video gastroscopy and blood analysis. A controlled postprandial glucose curve for mango intake was also performed. Gastroscopies were performed at intervals of 15 days, starting in December, just before the beginning of the harvest, until the beginning of February, and days after the end of the harvest. Blood collection was performed on the same day between November and February for blood analysis. The results were submitted to ANOVA and Tukey’s test, with a significance level of p < 0.05. Gastroscopies indicated that four out of five horses had erosions and ulcers in the squamous region between 15 and 30 days after the start of the season. Biochemical tests indicated a reduction in plasma proteins during the harvest period, and the postprandial glucose curve showed concentrations above 200 mg/dL between 30 and 180 min after ingestion of 5.37 kg mangoes. The animals were not treated and recovered after 15 days of harvest and without ripe mangoes on the ground. It is concluded that the indiscriminate ingestion of mangoes favors the appearance of lesions in the gastric squamous region, to varying degrees, and that animals recover naturally after an average of 15 days from the end of the season when the animals return to their regular feeding with hay and grass pasture.

Large bowel obstruction by enteroliths and/or foreign bodies in domestic equids: retrospective study of cases seen from January 2003 to March 2020

ABSTRACT This retrospective study was based on data extracted from medical records of 48 horses with intestinal obstruction caused by enteroliths and/or foreign bodies seen over the course of 17 years. Data analysis was aimed at describing the major features of this type of colic. Obstructions caused by enteroliths, foreign bodies or both accounted for 40 (83.34%), 6 (12.50%) and 2 (4.16%) cases in this sample respectively. Affected horses were aged 1 to 32 years (mean age 9.5 years) and 14 horses were fed alfalfa. Alfalfa is thought to contribute to enterolith formation. Foreign bodies and enteroliths were found in the transverse (12 cases, 25%), the large or the small colon (10 cases, 20.83% respectively). Concurrent obstruction of different intestinal segments was also recorded. These involved the small and the large colon in 10 cases (20.83%), the transverse and the large colon in 4 cases (8.33%), the small and the transverse colon in 1 case (2.08%) and the transition from the large to the transverse colon in one case (2.08%). Short term survival was 77.08% overall and 87.50% when only patients submitted to postoperative treatment were accounted for. Survival data are consistent with survival rates of 91% reported in literature.

Nanoparticles in Equine Nutrition: Mechanism of Action and Application as Feed Additives

Several concerns exist regarding horse rearing such as environmental pollution, antibiotics resistance, digestive disorders, mycotoxins contamination of animal feed, gut health management, and improvement of feed efficiency. Nanoparticles have the potential to address these issues and thus could be used as feed additive. Citrate reduces and stabilizes gold nanoparticles, alongside biosynthesized silver nanoparticles have the potential to prolong and improve digestive enzyme activity, which would enhance starch digestibility in the stomach. Zinc oxide and selenium nanoparticles could be used to improve feed digestibility and volatile fatty acids production. Magnesium oxide, silver, and copper nanoparticles exhibit strong antimicrobial activity against gram-positive and gram-negative microbes and weaken the biofilm formation of the microbial community. Calcium, zinc, and silver nanoparticles could be used to prevent periodontal disease in horses. In addition, silver nanoparticles may be applied as antifasciolitics and potentially against other gastrointestinal parasites. Environmental concern of equines could be addressed by using cerium oxide, silver, and cobalt nanoparticles to reduce methane emission and zinc oxide could help to reduce fecal mineral output. Fullerol C₆₀[OH]_24, a honey-derived silver nanoparticle and zinc oxide nanoparticles exhibit attractive antibacterial properties because of increased specific surface area as the reduced particle enhance unit surface reactivity. Gut health management of equines could be solved with nanoparticles because of the ability of ferrous oxide and copper nanoparticles to improve microbial growth, whereas zinc oxide improves villus height, crypt depth, and villous surface area. It is required to explore in depth the beneficial effects of these nanoparticles as a novel area in the equine industry's both in vitro and in vivo before recommendation to equine owners.