Miniature Horse Research Articles

Genetic factors underlying Mandibular prognathism: insights from recent human and animal studies.

This review aims to provide an updated overview of the genetic etiology of mandibular prognathism (MP), focusing on recent research efforts, to summarize the findings from human studies utilizing genome-wide association studies (GWAS), candidate gene analyses, whole exome sequencing (WES) and single-nucleotide polymorphisms (SNPs) in relation to MP. Additionally, insights from animal studies are incorporated to understand the molecular mechanisms underlying mandibular development and the pathogenesis of MP. A comprehensive literature search was conducted to identify relevant studies on the genetic basis of MP. Human studies employing GWAS, candidate gene analyses, and SNPs investigations were reviewed. Animal studies, including European seabass, zebrafish, transgenic mouse and miniature horse were also examined to provide additional insights into mandibular development and MP's pathogenesis using GWAS, WES, transgenic techniques, morpholino antisense oligos and homozygote. Human studies have identified multiple loci and genes potentially associated with MP through GWAS, candidate gene analyses, and SNP investigations. Animal models have contributed valuable information about the molecular mechanisms involved in mandibular development and the development of MP. Recent research efforts have enhanced our understanding of the genetic etiology of MP. Integration of genetic studies with functional analyses has shed light on key signaling pathways and gene regulatory networks implicated in MP.

Computed tomographic angiography of a presumed acquired transhepatic portosystemic shunt in a miniature horse filly.

A 1-year-old Miniature Horse filly was presented for chronic lethargy and hyporexia. Elevated liver enzymes, bile acids, and ammonia were noted on bloodwork. The primary differential diagnosis was a portosystemic shunt (PSS). Three-phase computed tomographic angiography findings were consistent with a transhepatic portosystemic shunt. Percutaneous liver biopsy confirmed severe diffuse hepatic changes, most likely due to chronic pyrrolizidine alkaloid toxicosis, and medical management was elected. Based on an extensive literature review, this is the first report of a transhepatic portosystemic collateral vessel in a horse. Computed tomographic angiography is feasible and useful for the diagnosis of PSS in miniature horses.

Parotid duct sialolithiasis in three Caspian miniature horses

AbstractThree Caspian miniature horses, exhibiting facial swellings, were examined in Alborz province. Physical examinations denoted sialolithiasis in two patients, and arose suspicion of the same condition in the third patient. The sialoliths were removed using a transcutaneous surgical approach with standing sedation using xylazine (1 mg/kg, intravenously) and local anaesthesia with lidocaine (5–10 mL) in all three patients. In Case 1, multiple pieces of stone were excised from the left parotid duct using a transcutaneous approach. In Case 2, a single oval‐shaped stone (44 g) was excised from the right parotid duct with the same technique as mentioned above. Case 3 presented a 1‐g amorphous stone partially obstructing the right parotid duct, resulting in cyst formation on the right aspect of the face. Chemical analysis identified calcium carbonate as the primary component. Given the distribution of horses in Iran, accurate estimation of the frequency of sialolithiasis is quite challenging, and numerous cases are overlooked.

Ponies, miniatures, and younger equids are at higher risk of fecalith obstruction compared to a general colic population.

To determine breed, age, and sex predispositions for fecalith obstruction and to evaluate short-term survival and prognostic factors following surgical treatment of fecalith intestinal obstruction in equids. 151 equids. Medical records of equids undergoing surgery for fecalith obstruction from 2000 to 2020 were reviewed. Signalment, history, presenting clinicopathological data, surgical findings, complications, and short-term survival were recorded and compared between survivors and nonsurvivors. Signalment of the fecalith population was compared to a contemporaneous colic population. Clinical factors were assessed for association with outcome. 64 females, 53 castrated males, and 31 intact males were included. Three equids presented twice. Miniature horses, ponies, and miniature donkeys/mules represented 48% (71/148) of fecalith population and full-sized breeds represented 52% (77/148). Miniature horses and ponies were overrepresented and equids ≤ 1 year of age were overrepresented in the fecalith population compared to the colic population. One hundred thirty-nine equids (92%) survived to discharge, 6% (9/148) were euthanized intraoperatively, and 2% (3/148) were euthanized during hospitalization. Nonsurvivors showed more severe colic signs on admission, tachycardia on admission, and hyperlipemia. Equids with postoperative colic (P = .01) and complications (P = .002) were less likely to survive. Miniature horses and ponies were overrepresented compared to the colic population; however, full-sized breeds were also affected. Surgical treatment had an excellent short-term prognosis. Severe colic signs, tachycardia, hyperlipemia, postoperative colic, and surgical complications negatively affected short-term survival.

Effect of probiotics and prebiotics on the composition of the equine fecal and seminal microbiomes and sperm quality: A pilot study

Probiotic and prebiotic effects on equine semen and gastrointestinal microbiome composition and sperm quality are unknown. This study aimed to evaluate the effects of pre-, pro- or synbiotic supplementation on fecal and semen microbiome composition and sperm quality parameters of stallions. This Latin square crossover trial involved four miniature pony stallions receiving control diet only, or addition of a pro-, pre- or synbiotic formulation. Full-length 16S rRNA gene amplicon sequencing was used to measure diversity of semen and fecal microbiomes. Total sperm count, total motility, progressive motility, DNA integrity, lipid peroxidation and mitochondrial oxidative stress, biomarkers of sperm quality, were measured after each intervention. A general linear model was employed to analyse and compare microbiome diversity measures and sperm quality data across four time points. Shannon's diversity index (alpha-diversity), and evenness of semen and gastrointestinal microbiomes were significantly different (p<0.001). A trend was observed for prebiotic effects on the diversity indices of the GI microbiome (p= 0.07). No effects of treatments were observed on either semen microbiome or sperm quality. Pre-, pro- and synbiotic supplements showed no negative effect on sperm quality parameters observed. This proof of concept provides preliminary data to inform future studies exploring the relationship between microbiomes and fertility.

The semen microbiome of miniature pony stallions.

Little is known about the microbial composition of stallion semen. To describe the microbiota detected in equine semen of healthy miniature pony stallions. Semen specimens were collected using a Missouri artificial vagina at a single time point. PacBio (Pacific Biosciences) genomic DNA sequencing of the 16S rRNA gene was performed on these specimens, following which next-generation microbiome bioinformatics platform QIIME2 was used to process fastq files and analyse the amplicon data. The data were categorised into genus, family, class, order and phylum. Firmicutes and Bacteroidetes phyla predominated (76%), followed by Proteobacteria (15%). Bacteroidales, Clostridiales and Cardiobacteriales predominated the microbial rank of order (86%). Class was mainly composed of Bacteroidia, Clostridia and Gammaproteobacteria (87%), while family was mainly composed of Porphyromonadaceae , Family_XI and Cardiobacteriaceae (62%). At the level of genus, 80% of the abundance was composed of seven genera, namely Porphyromonas, Suttonella, Peptoniphilus, Fastidiosipila, Ezakiella, Petrimonas and an unknown taxon. The findings indicate that specific microbiota may be characteristic of healthy miniature pony stallions' semen with some inter-individual variations observed. Larger equine studies involving fertile and infertile subjects could be informed by this study and could explore the relationship of the semen microbiome to male fertility.

Immortalization of American miniature horse-derived fibroblast by cell cycle regulator with normal karyotype.

Immortalized cells serve as a crucial research tool that capitalizes on their robust proliferative properties for functional investigations of an organism. Establishing an immortalized American miniature horse cell line could yield valuable insights into these animals' genetic and physiological characteristics and susceptibility to health issues. To date, immortalized small horse cells with normal karyotypes have not been established. In this study, we successfully established primary and immortalized fibroblast cell lines through the combined expression of human-derived mutant cyclin-dependent kinase 4 (CDK4R24C), cyclin D1, and Telomerase Reverse Transcriptase (TERT), although CDK4R24C and cyclin D1, SV40T and TERT did not result in successful immortalization. Our comparison of the properties of these immortalized cells demonstrated that K4DT immortalized cells maintain a normal karyotype. Ultimately, our findings could pave the way for the development of targeted interventions to enhance the health and well-being of American miniature horses.

The prevalence and risk factors of dental disease found in 100 miniature horses

IntroductionDental disease is a common condition affecting horses. Its prevalence and characteristics among most of the common breeds of horses and donkeys have been investigated and described in the literature, but information about the prevalence and etiology of dental disease of miniature horses is sparse.MethodsTo determine the prevalence and characteristics of dental disease of miniature horses, we performed oral and dental radiographic examinations on 100 miniature horses. The findings of these examinations were analyzed to determine the prevalence of dental disease and its correlation to age, sex, weight, body condition score, height at the withers, head length and head width. Older horses had a higher prevalence of dental disease, diastemata and crown elongations.ResultsThe most common dental diseases detected in this population were crown elongation, oral mucosal ulceration, diastemata, class 1 malocclusion and hypodontia. Horses with a high body condition score had an increased likelihood of having a class 1 malocclusion. Horses with wider heads had a higher prevalence of dental disease and class 1 malocclusions.ConclusionFrequent oral examinations, starting at an early age, should be prioritized as a part of miniature horse preventive health care to decrease morbidity and slow progression of dental disease.

Diagnosis of equine endocrinopathies: The value of measuring blood glucose during an oral glucose test

Blood glucose concentration is often measured during an oral glucose test (OGT), but is not thought to aid in diagnosing insulin dysregulation (ID) or pituitary pars intermedia dysfunction (PPID). The aim of this retrospective study was to investigate whether the change in blood glucose concentration during an OGT aligned with indicators of equine metabolic syndrome or PPID, including serum insulin and plasma ACTH concentrations, clinical observations, age, sex, breed type and the test dose. The cohort included 149 horses, miniature horses, and ponies that had undergone an in-feed OGT and clinical examination between 2015 and 2021. The animals were diagnosed as either metabolically healthy, insulin-dysregulated, having PPID or both endocrinopathies. The mean ± standard error increase in blood glucose during the OGT was 3.41 ± 0.21 mM, and this change showed a weak positive correlation with the increase in serum insulin concentration (r = 0.36; P 0.001), body condition score (BCS; r = 0.26; P = 0.002) and cresty neck score (CNS; r = 0.38; P 0.001). The median [interquartile range] increase in blood glucose for miniature horses (5.25 [2.98–6.5] mM), was more than twice that seen in full-sized horses (2.4 [1.33–3.45] mM; P = 0.03). In metabolically healthy animals the increase in blood glucose during an OGT (+2.2 [1–3.5] mM) was smaller (P 0.001) than in animals with ID (+3.8 [2.73–5.33] mM), or both endocrine diseases (+6.1 [3.6–6.85] mM). There was an effect of the dose of dextrose on the blood glucose response, with higher doses yielding larger responses (P 0.001). The variability in these data support that basal and post-prandial blood glucose responses to an OGT are not appropriate as stand-alone diagnostic markers of ID or PPID. However, the association between blood glucose and CNS supports the use of CNS when evaluating animals for ID.

Pony patrols campus as goodwill ambassador for Virginia Tech

As students and staff walk the Virginia Tech campus, they hope to cross paths with their favorite miniature horse on patrol, blanketed in his very own Virginia Tech Police Department uniform and sporting VT bows in his mane and tail.

Development of a body condition index to estimate adiposity in ponies and horses from morphometric measurements.

There is a high prevalence of obesity in ponies and pleasure horses. This may be associated with equine metabolic syndrome and an increased risk of laminitis. Body condition scoring (BCS) systems are widely used but are subjective and not very sensitive. To derive a body condition index (BCI), based on objective morphometric measurements, that correlates with % body fat. Retrospective cohort study. Morphometric measurements were obtained from 21 ponies and horses in obese and moderate body condition. Percentage body fat was determined using the deuterium dilution method and the BCI was derived to give the optimal correlation with body fat, applying appropriate weightings. The index was then validated by assessing inter-observer variation and correlation with % body fat in a separate population of Welsh ponies; and finally, the correlation between BCI and BCS was evaluated in larger populations from studies undertaken in Australia, the United Kingdom and the United States. The BCI correlated well with adiposity in the ponies and horses, giving a Pearson r value of 0.74 (P < 0.001); however, it was found to slightly overestimate the % body fat in leaner animals and underestimate in more obese animals. In field studies, the correlation between BCI and BCS varied particularly in Shetlands and miniature ponies, presumably due to differences in body shape. Further work may be required to adapt the BCI to a method that is more applicable for Shetlands and miniature ponies. This BCI was able to provide an index of adiposity which compared favourably with condition scoring in terms of accuracy of estimating adiposity; and was more consistent and repeatable when used by inexperienced assessors. Therefore, this may be a useful tool for assessing adiposity; and may be more sensitive than condition scoring for tracking weight gain or weight loss in individual animals.

Computer-assisted surgery for placing toggle constructs across the coxofemoral joints of small equids using a minimally invasive approach-A proof-of-concept cadaveric study.

To develop a minimally invasive technique for placing a toggle construct across the coxofemoral joint of small equids using computer-assisted surgery. Experimental cadaveric study. Three pilot specimens: One donkey, one Shetland pony and one Warmblood foal. Six main study specimens: Three Shetland ponies, one American Miniature Horse, one Warmblood foal and one donkey. Experimental surgeries were performed on both coxofemoral joints of each cadaver. Using a minimally invasive surgical approach, 5.5 mm bone canals were drilled through the femur and acetabulum, traversing the coxofemoral joint. Intraoperative guidance was provided by a cone-beam computed tomography (CBCT)-coupled surgical navigation system. A toggle construct was introduced through the bone canals. Surgical accuracy aberrations (SAA) were measured at the femoral entry and exit points and at the acetabular entry point on merged pre- and postoperative CBCT scans. The coxofemoral joint was assessed for articular cartilage damage by gross dissection. A toggle construct was placed across all 18 coxofemoral joints. The overall median SAA in the main study was 2.8 mm (range: 0.4-8.0 mm). No cartilage damage was found in the cadaveric specimens of the main study. The described technique allowed for the placement of a toggle construct across the coxofemoral joint of small equid cadaveric specimens without prior coxofemoral luxation. This technique may serve as an option for surgical stabilization of coxofemoral joints in small equids. Further biomechanical investigations are required to assess optimal implant positioning and toggle constructs.

Exterior features of American miniature horses of the pony farm "Idalgo"

The main task of preserving populations of small breeds of horses imported from abroad with their unique characteristic features of the exterior and type of constitution is the organization of the reproduction of the livestock and the preservation of the exterior parameters of the breed in descendants. In modern conditions of a small number of populations of such breeds, the influence of the inbreeding depression factor increases, as well as the manifestation of recessive mutations and hereditary pathologies in the offspring.[8] On the one hand, this can form changes that are not typical for the breed: phenotype, measurements, body type of the animal's format; on the other hand, such features of breeding horses in the absence of a selection press and selection will lead to the formation of a population of horses of the breed type. Such breed types should be fixed by breed leaders and have a territorial localization; if this does not happen, then the livestock that does not meet the requirements of the breed may lose the status of purebred. [2][6] The study consisted in monitoring the indicators of measurements by generation to identify the dynamics of changes in the format of the horse population and their compliance with the breed standard of American miniature pony horses. The article presents the indicators of the main measurements of American miniature pony horses for a number of generations and carried out their comparative analysis, with the standard requirements of the corresponding measurements of the breed. The analysis showed the following dynamics: in height at the withers, the increase is 46.5%, in the oblique length of the body, the increase is 97.8%, in the distance from the withers to the tail, the increase was 103.5%, which characterizes a more intensive growth of the peripheral skeleton in the postembryonic period and the formation of an elongated format with age . While the angle of the shoulder, wrist and tarsus is less variable in the age aspect and depends on individual hereditary factors, and not on age. A number of recommendations have been developed for specialists of the club "IDALGO" on the selection of parental pairs for correction for compliance with the standard requirements for measuring indicators in offspring.

Dystocia in Miniature Horses and Shetland ponies: assisted vaginal delivery, fetotomy and field Caesarean section

Dystocia in the horse is a life-threatening emergency. Prompt and effective intervention is essential to improve the outcome for both mare and foal. Resolution is possible via assisted vaginal delivery, controlled vaginal delivery, fetotomy or Caesarean section. Guidelines exist but the final choice is influenced by several factors including fetal viability, duration of dystocia, availability of obstetric assistance and financial considerations. The purpose of this study was to report our experience in the management of dystocia in Miniature horses and Shetland ponies. Data were collected from the records of 17 mares treated between 2020 and 2022. According to the clinic's protocol, correction was first attempted by assisted vaginal delivery; in case of failure, fetotomy or Caesarean section was performed. All mares were referred to the clinic after prolonged labor and only 2 (12%) were presented with their foal still alive. In 8/17 mares, the foal was delivered via assisted vaginal delivery. In 6/17 mares, a partial fetotomy was performed. In the 3 remaining cases, a conventional Caesarean section was proposed but not considered due to its financial cost; a field Caesarean section was therefore performed. General anesthesia was maintained using a continuous rate infusion of triple drip consisting of a combination of 250 ml sodium chloride (0.9%), 250 ml guaifenesin (10%), 20 ml ketamine (10%) and 1 ml detomidine (1%).After local anesthesia, a low left flank celiotomy in lateral recumbency was performed. Overall survival rate of the presented mares was 59% (10/17). Mares’ survival rates following assisted vaginal delivery, fetotomy and field Caesarean section were respectively 63% (5/8), 33% (2/6) and 100% (3/3). Both foals alive at arrival survived delivery and one (6%) survived to discharge. While in warmblood horses, fetotomy has been proven rapid and safe (Norton et al. Equine Vet J 2007;39:37-41), in small breeds the feasibility of fetotomy is largely hampered by their body size and is deemed too stressful for the exhausted mares. In addition, complications after dystocia are aggravated in small breeds due to the high risk of hypertriglyceridemia and consequently hyperlipemia. Hypertriglyceridemia was determined in 35% (6/17) of the mares and hyperlipemia was the cause of death in 3 out of these 6 mares. Caesarean section is associated with several complications, such as retained placenta, metritis, laminitis and uterine hemorrhage. Due to a lack of asepsis in a non-optimal setting, peritoneal or incisional infections could be a weak point of the field Caesarean section. Our results, supported by those of others (Gandini et al. Reprod Dom Anim 2013;48:49-51), are promising for considering field Caesarean section as a preferable resolution to dystocia in Miniature horses and Shetland ponies.

A novel method for isolation of functional stallion spermatozoa for artificial insemination

In vitro semen purification techniques have been developed that seek to mimic the in vivo selection process, in order to generate the highest possible chance of oocyte fertilization following artificial insemination (Morrell and Rodriguez-Martinez. Vet Med Int. 2011:894767). Since this practice began, there have been many methods developed in an attempt to isolate functional spermatozoa for AI, yet only one method is routinely used – density gradient centrifugation using commercial preparations such as EquiPure. Here, we have developed a novel method of isolating functional spermatozoa and compared sperm quality to spermatozoa isolated with EquiPure. The AI-Port system (Memphasys, Sydney, Australia), comprises a disposable cartridge consisting of a sample chamber – where extended semen is deposited, and a harvest chamber – where isolated spermatozoa is extracted. These chambers are separated by a 5 µm nylon woven membrane, through which highly motile spermatozoa are able to swim from the sample chamber into the harvest chamber over 20 min, leaving behind seminal plasma and other cell types such as leukocytes. Spermatozoa were collected from miniature pony stallions, and immediately extended with EquiPlus semen extender. The ejaculate was split, and spermatozoa were isolated into BWW media with EquiPure (as per manufacturer's instructions; Nidacon, International), or the AI-Port system. Comparisons were conducted between spermatozoa isolated with the AI-Port and EquiPure, which revealed that the yield of AI-Port samples was significantly lower (25.5±5.9%) incomparison to EquiPure samples (44.9±10.2%; Kruskal-Wallis), potentially solvable with prototype improvement. Viability (Eosin-nigrosin) of AI-Port samples was significantly higher than EquiPure samples (94.4±1.1 vs 81.5±2.1%; P≤0.01; ANOVA; respectively). In regard to motility, total motility for AI-Port samples was significantly higher than EquiPure samples (93±1.3 vs 89.5±2.9%; P≤0.05; ANOVA; respectively). Whilst there was no significant difference for progressive motility between AI-Port and EquiPure samples (45.7±3.2 vs 45.6±3.4%; ANOVA; respectively). Both samples were higher than the progressive motility of the initial non-purified ejaculate (30±4.1%; P≤0.05). Mitochondrial superoxide was measured with flow cytometry and MitoSOX red. Likewise, there was no significant difference in superoxide levels between AI-Port and EquiPure samples (10.2±3.1 vs 5.6±0.8%; ANOVA; respectively). However, both samples had a reduced level of superoxide generation compared to the initial non-purified ejaculate (32.5±20.2%; P≤0.05). The DNA integrity was measured with the Halo test, which confirmed AI-Port samples had less DNA damage than EquiPure™ samples (2.0±0.5 vs 10.2±2.1%; ANOVA; P≤0.01; respectively). In summary, the AI-Port effectively isolates high-quality spermatozoa at a comparable or superior level to EquiPure. Its cost-effectiveness and user-friendliness make it a viable option for improving artificial insemination success rates in breeding programs.

Pony patrols campus as goodwill ambassador for Virginia Tech

As students and staff walk the Virginia Tech campus, they hope to cross paths with their favorite miniature horse on patrol, blanketed in his very own Virginia Tech Police Department uniform and sporting VT bows in his mane and tail.

Pony patrols campus as goodwill ambassador for Virginia Tech

As students and staff walk the Virginia Tech campus, they hope to cross paths with their favorite miniature horse on patrol, blanketed in his very own Virginia Tech Police Department uniform and sporting VT bows in his mane and tail.

Effects of therapeutic ultrasound and moderate heat on stallion testes

Transplantation of stem cells into dysfunctional testes is currently being investigated as a therapeutic option for men and stallions with advanced testicular degeneration. This series of “proof of concept” studies aimed to identify a safe and efficient method of inducing severe testicular degeneration to create an optimal equine recipient model for intratesticular stem cell transplantation (SCT). Two ex vivo and two in vivo experiments were conducted. At first, forty testes obtained from castrations were used to identify an effective therapeutic ultrasound (TUS) device and the protocol for increasing intratesticular temperature in stallions. Six min of treatment using the Vetrison Clinic Portable TUS machine raised the intratesticular temperature by 8°C-12.5 °C. This protocol was applied to treat three scrotal testes in three Miniature horse stallions, three times, every other day. Contralateral testes served as controls. There were signs of slight tubular degeneration in treated testes two and three weeks after TUS treatment. The number of seminiferous tubules (STs) with exfoliated germ cells (GCs) was increased in one testis only, three weeks after treatment. The degree of apoptosis of GCs was higher in each treated testis in comparison to the contralateral control testis. Next, the ability of various heating devices to increase intratesticular temperatures to at least 43 °C in stallion testes was tested, using twenty testes obtained from castrations. ThermaCare® Lower Back & Hip Pain Therapy Heatwrap (TC heat wrap) reliably increased intratesticular temperatures and kept them continuously between 43 °C and 48 °C for seven to 8 h. In the follow-up in vivo study, the left testes of three Miniature horse stallions were treated with TUS, after which both testes of each stallion were treated with moderate heat provided by the TC heat wrap (three times, every other day, for 5 h each time). There were signs of moderate tubular degeneration in the samples from all treated testes obtained three weeks after treatments (Heat only or Heat/TUS): areas with hypospermatogenesis, spermatogenic arrest, vacuolized Sertoli cells, numerous STs with exfoliated GCs, increased degree of GCs apoptosis, and changes in three histomorphometric numeric attributes of STs. We concluded that TUS or TC wraps increase intratesticular temperature of the isolated stallion testes. Further, treatment with TUS or moderate heat may induce mild to moderate degenerative changes in stallion testes. However, to achieve more robust result – severe testicular degeneration, our treatment protocol has to be modified.

Low Image Contrast Detection in a Bright Light Interference HDR Scene Using Smart CAOS Camera

Proposed and experimentally demonstrated is the linear low contrast detection capability of a smart design Coded Access Optical Sensor (CAOS) camera operating under interfering bright light conditions. This fine contrast imaging capability is delivered by engaging both the silicon CMOS sensor-mode of the constructed smart CAOS camera and deploying spatial filtering within its inherent on/off light routing structure via the Digital Micromirror Device (DMD). The camera uses the CMOS-mode identified non-bright light region of interest to engage the Code-Division Multiple Access (CDMA) CAOS-mode to achieve successful target imaging. Specifically, the low contrast variation (¡ 6 dB dynamic range) test target region of the toy horse target is successfully experimentally imaged within a near 87 dB High Dynamic Range (HDR) scene created by the presence of an external interfering bright visible light source. Applications scenarios that can benefit from the use of the proposed camera include natural bright light conditions surveillance as well as bright laser and LED targeted imaging across medical, industrial and scientific sectors.

Effects of Macleaya cordata extract supplementation on digestive parameters of ponies

ABSTRACT High amounts of grains in the equine diet led to high starch intake, causing gut alterations. Aimed at reducing harmful effects, Macleaya cordata extract (MCE) is a phytogenic additive that stands out for its antibiotic and anti-inflammatory effects proven in different species. However, there is no useful information for horses. The objective of this study was to evaluate the effects of different levels of the inclusion of commercial MCE on body weight (BW), body condition score (BCS), total apparent digestibility (AD) of nutrients, faecal pH and fermentative products, on ponies fed a high-starch diet. Eight healthy gelding Mini Horse ponies were used. The study design was contemporary double Latin-square 4 × 4 in the experimental unit, with the animal inside each experimental period (n = 8 experimental units per group). The experiment was conducted over four 20-d periods. Basal diet attended 1.75% BW dry matter daily and starch intake was 2.2 g/kg BW/meal. The experimental groups were as follows: control – without food additive; S1–1 mg/kg BW MCE; S1.5–1.5 mg/kg BW MCE and S2–2 mg/kg BW MCE. The data were analysed by PROC MIXED of SAS (p < 0.05). Tendency was considered when 0.05 < p < 0.1. Our results showed higher ether extract (EE) AD for S2 group (63.75%) when compared with the control (54.55%) (p = 0.0377). Lactate was lower (p = 0.0391) in S1 (3.27 mmol/l) and S2 (3.24 mmol/l) groups, although pH was not different between groups. Iso-valerate was greater in S1 group (2.29 mmol/l; p = 0.0289), and a tendency of higher butyrate values was found for S1 and S2 groups (p = 0.0980). We concluded that MCE supplementation probably positively influences equine resident microbiota, improving EE AD and increasing iso-valerate concentration. It can also minimise harmful high-starch impact. We recommend further studies using MCE in horses for a better understanding of its local activity and possible benefits.