Volumetric measurements of paranasal sinuses and examination of sinonasal communication in healthy Shetland ponies: anatomical and morphometric characteristics using computed tomography.

BACKGROUND: Despite clinical importance and frequent occurrence of sinus disease, little is known about the size of paranasal sinuses and their communication in ponies and small horses. To examine the shape and volume of the paranasal sinuses and evaluate the sinonasal communication, three-dimensional (3D) reconstructions of computed tomography (CT) datasets of 12 healthy adult Shetland ponies were performed and analysed. Linear measurements of head length and width were taken. Using semi-automatic segmentation, 3D-models of all sinus compartments were created. Volumetric measurement of the seven sinus compartments were conducted and statistical analysis was performed. Sinus volumes were compared between the left and right sinuses and the relation to age and head size was evaluated. RESULTS: Structure and shape of the paranasal sinus system in Shetland ponies was similar to that of large horses. All seven sinus compartments on each side of the head were identified (rostral maxillary sinus, ventral conchal sinus, caudal maxillary sinus, dorsal conchal sinus, middle conchal sinus, frontal sinus, sphenopalatine sinus). The existence of a bilateral cranial and a caudal system formed by a maxillary septum was visible in all 12 individuals. The volumetric sizes of the left and right sinuses did not differ significantly (p > 0.05). A positive correlation between the size of the paranasal sinuses and the head length was shown. A relation between sinus volumes and age could not be proved in adult ponies aged > six years. Communication between single sinus compartments was identified. Furthermore, communication with the nasal cavity over the nasomaxillary aperture (Apertura nasomaxillaris) and a common sinonasal channel (Canalis sinunasalis communis) as well as its splitting up into a rostral and a caudolateral channel could be seen. Examination of the sinonasal communication was challenging and only a descriptive evaluation was possible. CONCLUSIONS: Our findings concerning the size, shape and volumetric dimensions of Shetland pony CT images could help improve CT interpretation of abnormal clinical cases as well as aiding clinicians to develop and select appropriate instruments for medical inspection and treatments.

First report of zoonotic Cryptosporidium parvum GP60 subtypes IIaA15G2R1 and IIaA16G3R1 in wild ponies from the northern Iberian Peninsula.

Studies on the prevalence and molecular characterization of Cryptosporidium spp. affecting feral horses are scarce. The highland areas of the northern Iberian Peninsula are home to a large population of wild ponies which generally roam free in the ancient natural range and are subjected to a traditional exploitation regime. In the present study, a total of 79 non-diarrhoeal faecal samples from the wild ponies were collected from the ground immediately after defecation. Cryptosporidium was detected in 10 of the samples (12.6%) by a direct immunofluorescence antibody test and DNA amplification and sequencing. Analysis of partial sequences of the small subunit ribosomal RNA (SSU-rRNA) and heat shock protein (hsp70) loci revealed the presence of Cryptosporidium parvum. In addition, amplification and sequencing of a fragment of the 60-kDa glycoprotein (GP60) locus identified C. parvum subtypes IIaA15G2R1 and IIaA16G3R1. This study reports, for the first time, the occurrence of C. parvum in wild ponies in Europe, specifically in the northern Iberian Peninsula. Identification of the common subtype IIaA15G2R1 and also subtype IIaA16G3R1 (first description) indicates that these hosts may play a role in the sylvatic transmission of C. parvum and that they may act as a reservoir of zoonotic cryptosporidiosis.

Influences of different dietary contents of macrominerals on the availability of trace elements in horses.

In this study, influences of a reduced macromineral intake on the trace element metabolism in horses at maintenance were investigated. Background of this study is the revised recommendation on the macromineral supply for horses (GfE ). Balance studies on three adult pony geldings with body weights of 405 / 348 / 384 kg were performed to obtain data on apparent digestibility (aD), retention and serum concentrations of different trace elements (Cu, Zn, Se) at different dietary macromineral levels. A mineral supplement or a complementary feed-with a reduced macromineral content-was added to a hay-based diet (daily 5.5 kg hay per animal, split in three servings a day), beside distilled water was offered. The diets were offered one after the other in a way that all ponies had the same sequence of treatments. The native macromineral contents of the daily offered amount of hay already surpassed the new recommendations whereas dietary trace elements needed to be supplemented. There were no statistically significant differences (p ≤ .05) concerning the aD of copper, zinc and selenium comparing the diets with and without macromineral supplementation. Serum levels of these three trace elements were not affected by the different macromineral content of the diet. Results of this study, based on a 22-day feeding period for each treatment, indicate that a macromineral supplementation of a hay-based diet for adult horses at maintenance was not necessary. However, no negative effects of added macrominerals on the trace element metabolism occurred in this study.

Comparison of respiratory function during TIVA and isoflurane anaesthesia in ponies Part II: breathing patterns and transdiaphragmatic pressure.

OBJECTIVE: To compare breathing patterns and transdiaphragmatic pressure during total intravenous (TIVA) and isoflurane anaesthesia in ponies. STUDY DESIGN: Experimental, cross-over study. ANIMALS: Six healthy ponies weighing 286 (233-388) ± 61 kg, age 13 (9-16) ± 3 years. METHODS: Following premedication with romifidine [80 µg kg(-1) intravenously (IV)], general anaesthesia was induced with midazolam (0.06 mg kg(-1) IV) and ketamine (2.5 mg kg(-1) IV) and maintained with either isoflurane (Fe'Iso = 1.1%) (T-ISO) or an IV combination of romifidine (120 µg kg(-1) per hour), midazolam (0.09 mg kg(-1) hour(-1)) and ketamine (3.3 mg kg(-1) hour(-1)) (T-TIVA), while breathing 60% oxygen (FIO(2)). The circumference changes of the rib cage (RC) and abdominal compartment (ABD) were recorded using respiratory ultrasonic plethysmography (RUP). Balloon tipped catheters were placed in the distal oesophagus and the stomach and maximal transdiaphragmatic pressure (Pdi max) was calculated during Mueller's manoeuvre. RESULTS: The breathing pattern T-ISO was more regular and respiratory rate significantly lower compared with T-TIVA. Ponies in T-TIVA showed regularly appearing sighs, which were never observed in T-ISO. Different contribution of the RC and ABD compartments to the breathing pattern was observed with a smaller participation of the RC to the total volume change during T-ISO. Transdiaphragmatic pressures (mean 13.7 ± SD 8.61 versus 23.4 ± 7.27 cmH(2) O, p < 0.0001) were lower in T-TIVA compared to T-ISO [corrected]. The sum of the RC and ABD circumferential changes was lower during T-TIVA compared to T-ISO (6.32 ± 4.42 versus 11.72 ± 4.38 units, p < 0.0001). CONCLUSION AND CLINICAL RELEVANCE: Marked differences in breathing pattern and transdiaphragmatic pressure exist during inhalation- and TIVA and these should be taken into account for clinical estimation of anaesthetic depth.

Minimum end-tidal sevoflurane concentration necessary to prevent movement during a constant rate infusion of morphine, or morphine plus dexmedetomidine in ponies.

OBJECTIVE: To compare the effects of a constant rate infusion (CRI) of dexmedetomidine and morphine to those of morphine alone on the minimum end-tidal sevoflurane concentration necessary to prevent movement (MACNM ) in ponies. STUDY DESIGN: Prospective, randomized, crossover, 'blinded', experimental study. ANIMALS: Five healthy adult gelding ponies were anaesthetized twice with a 3-week washout period. METHODS: After induction of anaesthesia with sevoflurane in oxygen (via nasotracheal tube), the ponies were positioned on a surgical table (T0), and anaesthesia was maintained with sevoflurane (Fe'SEVO 2.5%) in 55% oxygen. Monitoring included pulse oximetry, electrocardiography and measurement of anaesthetic gases, arterial blood pressure and body temperature. The ponies were mechanically ventilated and randomly allocated to receive IV treatment M [morphine 0.15 mg kg⁻¹ (T10-T15) followed by a CRI (0.1 mg kg⁻¹ hour⁻¹)] or treatment DM [dexmedetomidine 3.5 µg kg⁻¹ plus morphine 0.15 mg kg⁻¹ (T10-T15) followed by a CRI of dexmedetomidine 1.75 µg kg⁻¹ hour⁻¹ and morphine 0.1 mg kg⁻¹ hour⁻¹]. At T60, a stepwise MACNM determination was initiated using constant current electrical stimuli at the skin of the lateral pastern region. Triplicate MACNM estimations were obtained and then averaged in each pony. Wilcoxon signed-rank test was used to detect differences in MAC between treatments (α = 0.05). RESULTS: Sevoflurane-morphine MACNM values (median (range) and mean ± SD) were 2.56 (2.01-4.07) and 2.79 ± 0.73%. The addition of a continuous infusion of dexmedetomidine significantly reduced sevoflurane MACNM values to 0.89 (0.62-1.05) and 0.89 ± 0.22% (mean MACNM reduction 67 ± 11%). CONCLUSION AND CLINICAL RELEVANCE: Co-administration of dexmedetomidine and morphine CRIs significantly reduced the MACNM of sevoflurane compared with a CRI of morphine alone at the reported doses.

Comparison of respiratory function during TIVA (romifidine, ketamine, midazolam) and isoflurane anaesthesia in spontaneously breathing ponies Part I: blood gas analysis and cardiorespiratory variables.

OBJECTIVE: To compare pulmonary function and gas exchange in ponies during maintenance of anaesthesia with isoflurane or by a total intravenous anaesthesia (TIVA) technique. STUDY DESIGN: Experimental, cross-over study. ANIMALS: Six healthy ponies weighing mean 286 (range 233-388) ± SD 61 kg, age 13 (9-16) ± 3 years. METHODS: The ponies were anaesthetized twice, a minimum of two weeks apart. Following sedation with romifidine [80 µg kg(-1) intravenously (IV)], anaesthesia was induced IV with midazolam (0.06 mg kg(-1)) and ketamine (2.5 mg kg(-1), then maintained either with inhaled isoflurane (Fe'Iso = 1.1 vol%) (T-ISO) or an IV infusion of romifidine (120 µg kg(-1) hour(-1)), midazolam (0.09 mg kg(-1) hour(-1) IV) and ketamine (3.3 mg kg(-1) hour(-1)) (T-TIVA). Ponies were placed in lateral recumbency. Breathing was spontaneous and Fi'O(2) 60%. After an instrumentation/stabilisation period of 30 minutes, arterial and mixed venous blood samples were taken simultaneously every 10 minutes for 60 minutes and analysed immediately. Oxygen extraction ratio (O(2)ER) and venous admixture were calculated. Tidal volume (TV), minute volume (MV), respiratory rate (f(R)), packed cell volume (PCV), arterial blood pressure and heart rate (HR) were measured and recorded. Data were analysed with mixed model anova (α = 0.05). Treatments were compared overall and at two selected time points (T30 and T60) using Bonferroni correction. RESULTS: Arterial and mixed venous partial pressures of O(2) and CO(2), and TV were significantly lower and MV and f(R) were higher in T-TIVA compared to T-ISO. Venous admixture did not differ between treatments. O(2) R was significantly higher in T-TIVA. Mean arterial pressure was higher and HR was lower in T-TIVA compared to T-ISO. CONCLUSIONS AND CLINICAL RELEVANCE: Whilst arterial CO(2) was within an acceptable range during both protocols, the impairment of oxygenation was more pronounced with the T-TIVA evidenced by lower arterial and venous oxygen partial pressures.

Analysis of the season-dependent component in the evaluation of morphological and biochemical blood parameters in Shetland ponies of both sexes during exercise.

Introduction: Determination of morphological and biochemical blood indices facilitates assessment of the health and welfare of horses, their nutrient demand, the effects of training already undertaken, and the horses' suitability for exercise. Identification of the season-dependent components and the effects of sex and exercise on changes in frequently referenced haematological and biochemical parameters was the main goal of the current study. Material and Methods: The blood morphology of 21 healthy adult Shetland ponies (11 mares and 10 stallions) aged 6.5 ± 1.4 years from the central Pomeranian region in Poland was analysed. Blood samples were taken once per season for one year. Results: No statistically significant season-dependent differences were found in the blood morphology parameters in either mares or stallions before or after exercise. Beta-coefficient results revealed the strength and type of the relationship of red blood cell distribution width (RDW) and granulocyte count (GRA) with the season, of red blood cell count (RBC), haematocrit, mean corpuscular volume and mean platelet volume with the sex, and of RDW, white blood cell count, GRA and RBC with the exercise factor. Biomarkers demonstrating the relationship between aerobic and anaerobic levels of energy metabolism in the blood did not show any sex dependency in regression analysis. Conclusion: The sex-independence of energy metabolism biomarkers may indicate the universality of these parameters. Both seasonality itself and its combination with the exercise factor took part in the formation of effective adaptive reactions for maintenance of morphological blood indices in the ponies during exercise.

Equids in Equine Assisted Services: A Scoping Review.

Equid welfare in equine assisted services (EAS) is an area that has received attention, but less attention than the documentation of human outcomes in response to EAS. To safeguard the well-being of equids and minimize human risk of injury, continued research on the effects of EAS programming and participants on equids needs to occur. The aims of this systematic scoping review were to identify the approaches taken for describing and understanding equids in EAS and the methods employed in evaluating equids' responses to EAS programming, participants, or both. Literature searches were performed in relevant databases to identify titles and abstracts for screening. Fifty-three articles were identified for full-text review. Fifty-one articles met the inclusion criteria and were retained for information and data extraction. The qualitative grouping of articles by study aim resulted in four categories: (1) characterization and description of equids in EAS; (2) the acute responses of equids to EAS programming, participants, or both; (3) the effects of management practices; and (4) the chronic responses of equids to EAS programming and participants. The latter three areas are in need of more research, especially as it relates to differentiating acute and chronic effects of EAS on the equids involved. Detailed reporting of information on study design, programming and participant characteristics, equid demographics, and workload are needed to facilitate comparison among studies and permit eventual meta-analysis of studies. Multi-faceted approaches including an array of measurements as well as relevant and informative control groups or conditions are required to identify the complex effects of EAS work on equids, their welfare, well-being, and affective states.

Strip grazing: Changes in biomass, nutrient content and digestibility of temperate, midsummer pasture by strip-grazed or 'free'-grazing ponies, over 4 weeks.

The digestibility and nutritive values of pastures that were either freely or strip-grazed for 28 days were compared. Twelve ponies were individually grazed in adjacent, 10 m wide, rectangular paddocks. On day -1, each paddock length was adjusted to contain a 28-day supply of herbage DM at 1.5 % of pony BW/d. Ponies, (4/treatment) either accessed the entire 28-day supply from day 1 (TA), or gradually via strip-grazing treatments, SG1 and SG2. SG1 had a 'lead' fence spanning the paddock width that from day 3 was moved forward 1/26th of the paddock length daily, whereas SG2 had an additional 'back fence', that was advanced the same distance as the lead fence daily. Pasture nutrient contents and estimated nutrient digestibilities (eD) were determined weekly. From weeks 1-4, mean strip-grazed pasture contents (% DM) of water-soluble carbohydrate (WSC) and crude protein declined from 15.7-10.2 and 9.4-8.7, respectively, whereas neutral- and acid-detergent fibre increased from 53.6-60.5 and 35.2-38.0, respectively. Corresponding values for TA pastures were 17.7-5.2, 8.9-8.7, 54.6-69.2 and 35.7-43.6. Concomitantly, calculated digestible energy (cDE) (MJ/kg DM) of strip-grazed and TA pastures declined from 9.7-8.9 and 9.6-7.8, respectively and eDMD of all treatments declined (P<0.05). By week 4, TA pasture WSC, cDE and eDMD were lower and fibre contents higher (P<0.05) than the strip-grazed pastures. TA animal cDE intakes in weeks 1 and 2 exceeded requirements by 42 % vs. 8 % by strip-grazed animals. Strip-grazing delivered a steadier nutrient supply than TA, potentially conferring health benefits to animals prone to metabolic dysfunction.

Genetic diversity within and between British and Irish breeds: The maternal and paternal history of native ponies.

The UK and Ireland have many native pony breeds with historical and cultural importance as well as being a source of uncharacterized genetic diversity. However, there is a lack of comprehensive research investigating their genetic diversity and phylogenetic interrelationships. Many studies contain a limited number of pony breeds or small sample sizes for these breeds. This may result in erroneous grouping of pony breeds that otherwise have intricate interrelationships with each other and are not evaluated correctly when placed as a token subset of a larger dataset. This is the first study that specifically investigates the genetic diversity within and between British and Irish native pony breeds using large sample numbers from locations of their native origin. This study used a panel of microsatellite markers and sequence analysis of the mitochondrial control region to analyze the genetic diversity within and between 11 pony breeds from Britain and Ireland. A large dataset was collected (a total of 485 animals were used for mtDNA analysis and 450 for microsatellite analysis), and previously published data were used to place the British and Irish ponies in a global context. The native ponies of Britain and Ireland were found to have had a complex history, and the interrelationships between the breeds were revealed. Overall, high levels of genetic diversity were maintained in native breeds, although some reduction was evident in small or isolated populations (Shetland, Carneddau, and Section C). Unusual mitochondrial diversity distribution patterns were apparent for the Carneddau and Dartmoor, although among breeds and global haplogroups there was a high degree of haplotype sharing evident, well-represented within British and Irish ponies. Ancestral maternal diversity was maintained by most populations, particularly the Fells and Welsh ponies, which exhibited rare and ancient lineages. The maternal and paternal histories of the breeds are distinct, with male-biased crossings between native breeds, and other shared influences, likely Arabs and Thoroughbreds, are apparent. The data generated herein provide valuable information to guide and implement the conservation of increasingly rare native genetic resources.

Novel Variants in the HMGA2 Gene Are Associated With Withers Height in Debao Pony.

The Debao pony is a well-known dwarf horse breed in China. High-mobility group AT-hook 2 (HMGA2) gene is regarded as one of the important candidate genes regulating body height in horses. The aim of this study was to study the association between mutations in HMGA2 gene and withers height in Debao ponies. The polymorphisms in all exons and partial introns of the HMGA2 gene were screened with sequencing across 180 Debao ponies. And the association between the DNA variants and withers height was analyzed. Seven genetic variants were identified in HMGA2 gene, including six novel variants. Among them, six mutations were located in two closed linked blocks. The three novel variants (In1-1, E5-1, and E5-2) in the 1st intron and the fifth exon and a known mutation (In1-2) had significant association with withers height in Debao ponies. These results suggest that the four variants have the potential to be used as genetic markers for dwarf horse breeding activities.

Fungal and chemical diversity in hay and wrapped haylage for equine feed.

The presence of fungi and mycotoxins in silage (fermented maize) for cattle and other ruminants have been studied extensively compared to wrapped haylage (fermented grass) for horses and other monogastric animals. The purpose of this work was to examine the fungal diversity of wrapped haylage and conventional hay and to analyse the forage sample for fungal metabolites. Faeces samples were also analysed to study the fate of fungi and metabolites. Fungal diversity of the samples was determined by direct plating on DG18, V8 and MEA and chemical analyses were done using LC-MS/MS. The results show that Sordaria fimicola was common in both hay and haylage, while Penicillium spp. was prevalent in haylage and Aspergillus spp. in hay. Communiols were found in all types of samples together with gliocladic acid. Roquefortines and fumigaclavines were found in haylage with no visible fungal growth, but not in hay. In haylage hot spot samples, a series of Penicillium metabolites were detected: Andrastins, fumigaclavines, isofumigaclavines, marcfortines, mycophenolic acid, PR toxins, and roquefortines. Penicillium solitum was found repeatedly in haylage and haylage hot spot samples and viridicatols were detected in a hot spot sample, which has not been reported before. Even haylage with no visible fungal growth contained more metabolites than hay. Individually, the metabolites detected in haylage may, in high doses, be mutagenic, neurotoxic or immunosuppressive; but the synergistic effect of small doses may also have other or greater negative health effects on equines than on ruminants.

Mouldable, thermoplastic, glue-on frog-supportive shoes change hoof kinetics in normal and obese Shetland ponies.

BACKGROUND: Obesity and hyperinsulinaemia are frequently encountered in the equine population and risk factors for the development of laminitis. There are many options for hoof support that claim a beneficial effect, but often the scientific evidence is scarce. OBJECTIVES: To quantify the effect of frog-supportive shoes on hoof kinetics in normal and obese ponies. STUDY DESIGN: Controlled in vivo trial. METHODS: Ten Shetland mares (n = 10) with a normal (n = 5) or obese (n = 5) body condition were led over a dynamically calibrated pressure plate before (T0), immediately after (T1) and 72 h (T2) after application of the shoes. The following locomotor variables were measured: stance duration (StDur), vertical impulse (VI), peak vertical force (PVF), time to PVF and time from PVF to lift off. The hoof print was divided into a toe and heel region and the StDur toe-heel index was calculated. The toe-heel hoof balance curves of the vertical force were plotted throughout the stance phase. RESULTS: The VI and PVF increased significantly 72 h after application of the shoes, when compared with T0 and T1. The StDur toe-heel index and toe-heel balance curves were significantly different between the normal and obese ponies. These variables became more comparable between the groups after application of the frog-supportive shoes. MAIN LIMITATIONS: It would have been interesting to measure the effect of the shoe in patients with acute laminitis. However, this would have had major welfare implications. CONCLUSIONS: The obese ponies moved more carefully than the normal group, demonstrated by a decreased loading of the toe area. The data illustrate that the ponies became more comfortable 72 h after application of the shoes, with a pronounced effect in the obese group. Thus, these results suggest that frog-supportive shoes could be beneficial, especially for obese ponies.

Incidence of laminitis and survey of dietary and management practices in pleasure horses and ponies in south-eastern Australia.

OBJECTIVES: The aims of this study were to (1) report the incidence of laminitis among a population of horses and ponies attending Pony Clubs in Victoria, Australia, and (2) describe the dietary and management practices of the sample population. METHODS: Researchers visited 10 Pony Clubs over a 10-month period. Horse and pony owners completed a questionnaire to provide information on management relating to diet and exercise. Owners were also asked to report their animal's history of laminitis, if any. RESULTS: From a survey population of 233 horses and ponies, 15.0% of animals (35 individuals) were reported to have suffered from at least one episode of laminitis. Of the animals that had suffered from laminitis, more than half had experienced multiple episodes. The majority of previously laminitic horses and ponies (71.4%) had not experienced an episode of laminitis within the past 12 months; however, 14.2% had experienced an incident within the past month. The proportion of ponies affected by laminitis (31/142; 21.8%) was significantly higher (P < 0.001) than the proportion of horses affected by laminitis (4/91; 4.4%). The incidence of laminitis within the pony group sampled was 6.5 cases per 100 pony years, while the incidence in horses was 0.55 cases per 100 horse years. CONCLUSION: This study provided information on the incidence of laminitis in the general population of pleasure horses and ponies in south-eastern Australia. It also provided an overview of dietary and management practices. Given the high incidence of animals that had been affected by laminitis (and the associated welfare implications), this study highlights the importance of owner education regarding appropriate feeding and management strategies to reduce the risk of laminitis.

Comparison and validation of ELISA assays for plasma insulin-like growth factor-1 in the horse.

Insulin-like growth factor-1 (IGF-1) plays several important physiological roles, and IGF-related pathways have been implicated in developmental osteochondral disease and endocrinopathic laminitis. This factor is also a downstream marker of growth hormone activity and its peptide mimetics. Unfortunately, previously used assays for measuring equine IGF-1 (radioimmunoassays and ELISAs) are no longer commercially available, and many of the kits on the market give poor results when used on horse samples. The aim of the present study was to compare three different ELISA assays (two human and one horse-specific). Plasma samples from six Standardbreds, six ponies and six Andalusians were used. The human IGF-1 ELISA kit from Immunodiagnostic Systems (IDS) proved to be the most accurate and precise of the three kits; the other two assays gave apparently much lower concentrations, with poor recovery of spiked recombinant human IGF-1 and unacceptably poor intra-assay coefficients of variation (CV). The IDS assay gave an intra-assay CV of 3.59 % and inter-assay CV of 7.31%. Mean percentage recovery of spiked IGF-1 was 88.82%, and linearity and dilutional parallelism were satisfied. The IGF-1 plasma concentrations were 123.21 ±8.24 ng/mL for Standardbreds, 124.95 ±3.69 ng/mL for Andalusians and 174.26 ±1.94 ng/mL for ponies. Therefore of the three assays assessed, the IGF-1 ELISA manufactured by IDS was the most suitable for use with equine plasma samples and may have many useful applications in several different research areas. However, caution should be used when comparing equine studies where different analytical techniques and assays may have been used to measure this growth factor.

Length of winter coat in horses depending on husbandry conditions.

This paper analyzes changes in the length of coat on selected body areas in horses and ponies kept under different husbandry (stable) conditions during the winter-spring period. The study included 12 Malpolski geldings and 12 geldings of Felin ponies aged 10-15 years. Horses were kept in two stables (six horses and six ponies in each stable). The type of performance, husbandry conditions and feeding of the studied animals were comparable. As of December 1, samples of hair coat from the scapula, sternum, back and abdomen areas of both body sides were collected seven times. The lengths of 20 randomly selected hair fibers were measured. Daily measurements of air temperature in the stables were also taken. An analysis of variance (ANOVA) was performed using the following factors: the body part from where the coat was sampled, the subsequent examination and the stable as well as the interaction between these factors. The significance of differences between means was determined with a t-Tukey test. The relations between air temperature in the stable and hair length were calculated using Pearson's correlation. It was found that air temperature in the stable impacts the length of winter coat in horses and ponies. The effect of this factor is more pronounced in ponies; as in the stables with lower temperatures it produces a longer hair coat which is more evenly distributed over the body in comparison with horses. Keeping horses and ponies in stables with a low air temperature accelerates coat shedding by approximately 25 days. Coat shedding begins from the scapula area.

Prevalence of obesity and owners' perceptions of body condition in pleasure horses and ponies in south-eastern Australia.

OBJECTIVE: To determine the prevalence of obesity within a population of pleasure horses and ponies in Victoria, Australia, and to compare owners' perceptions of their animals' body condition with researchers' assessments. DESIGN: An observational study plus owner questionnaire. METHODS: Ten Pony Club rallies in different regions of Victoria were attended. Information regarding 229 horses and ponies were obtained from owner questionnaires, and owners' perceptions of the current body condition of their animals were assessed using a visual analogue scale. Body condition score (BCS) was assessed by the researchers using the modified Henneke method. RESULTS: The prevalence of researcher-assessed obesity (BCS ≥7/9) in the total surveyed population was 23.1%. A higher prevalence of obesity was identified in Shetland ponies (71.5%) and other pony types (32.0%) compared with horse breeds (9.3%). Owners perceived their animals to be in significantly lower body condition compared with the researchers' assessments (P < 0.001). CONCLUSION: Although the overall prevalence of obesity within Australian pleasure horses and ponies was 24.5%, a considerably higher proportion of pony breeds fell into this category. Owners frequently underestimated their own animal's body condition. Knowing the prevalence of obesity in this population and understanding how owners perceive the body condition of their animals may help with targeting education around preventative health care, with the aim of reducing the risk of conditions such as insulin dysregulation and laminitis.

A cross-sectional epidemiological study of prevalence and severity of bit-induced oral trauma in polo ponies and race horses.

Bit and bridle accessories improperly fitted in ridden horses can cause oral trauma such as bone spurs, commissure ulceration, and tongue lacerations. This study was used to identify, grade, and compare the types of oral traumas commonly found within polo ponies and race horses. Injuries were assessed visually and by palpation on the tongue, lips' commissures, and interdental space. A total of 50 polo ponies and 50 race horses were sampled in the South of England. A Poisson model was successfully fitted to the data (p < .001), and the variables of discipline (p < .001), injury type (p < .001), and age (p < .001) were significant. Race horses with snaffle bits were predisposed to significantly higher severities and prevalence of oral trauma than were polo ponies in gag bits. Only polo ponies were observed with tongue trauma. Race horses had higher severities of injuries in the commissures and bone spurs. Positive correlations were found between age and/or time in sport and induced biting injuries. Polo ponies had been playing longer before the occurrence of injuries.

Propofol anaesthesia for surgery in late gestation pony mares.

OBJECTIVE: To characterize propofol anaesthesia in pregnant ponies. ANIMALS: Fourteen pony mares, at 256 ± 49 days gestation, undergoing abdominal surgery to implant fetal and maternal vascular catheters. MATERIALS AND METHODS: Pre-anaesthetic medication with intravenous (IV) acepromazine (20 µg kg-1), butorphanol (20 µg kg-1) and detomidine (10 µg kg-1) was given 30 minutes before induction of anaesthesia with detomidine (10 µg kg-1) and ketamine (2 mg kg-1) IV Maternal arterial blood pressure was recorded (facial artery) throughout anaesthesia. Arterial blood gas values and plasma concentrations of glucose, lactate, cortisol and propofol were measured at 20-minute intervals. Anaesthesia was maintained with propofol infused initially at 200 µg kg-1 minute-1, and at 130-180 µg kg-1 minute-1 after 60 minutes, ventilation was controlled with oxygen and nitrous oxide to maintain PaCO2 between 5.0 and 6.0 kPa (37.6 and 45.1 mm Hg) and PaO2 between 13.3 and 20.0 kPa (100 and 150.4 mm Hg). During anaesthesia flunixin (1 mg kg-1), procaine penicillin (6 IU) and butorphanol 80 µg kg-1 were given. Lactated Ringer's solution was infused at 10 mL kg-1 hour-1. Simultaneous fetal and maternal blood samples were withdrawn at 85-95 minutes. Recovery from anaesthesia was assisted. RESULTS: Arterial blood gas values remained within intended limits. Plasma propofol levels stabilized after 20 minutes (range 3.5-9.1 µg kg-1); disposition estimates were clearance 6.13 ± 1.51 L minute-1 (mean ±â€ŠSD) and volume of distribution 117.1 ± 38.9 L (mean ±â€ŠSD). Plasma cortisol increased from 193 ± 43 nmol L-1 before anaesthesia to 421 ± 96 nmol L-1 60 minutes after anaesthesia. Surgical conditions were excellent. Fetal umbilical venous pH, PO2 and PCO2 were 7.35 ± 0.04, 6.5 ± 0.5 kPa (49 ± 4 mm Hg) and 6.9 ± 0.5 kPa (52 ± 4 mm Hg); fetal arterial pH, PO2 and PCO2 were 7.29 ± 0.06, 3.3 ± 0.8 kPa (25 ± 6 mm Hg) and 8.7 ± 0.9 kPa (65 ± 7 mm Hg), respectively. Recovery to standing occurred at 46 ± 17 minutes, and was generally smooth. Ponies regained normal behaviour patterns immediately. CONCLUSIONS AND CLINICAL RELEVANCE: Propofol anaesthesia was smooth with satisfactory cardiovascular function in both mare and fetus; we believe this to be a suitable anaesthetic technique for pregnant ponies.

Intravenous anaesthesia using detomidine, ketamine and guaiphenesin for laparotomy in pregnant pony mares.

Objective To characterize intravenous anaesthesia with detomidine, ketamine and guaiphenesin in pregnant ponies. Animals Twelve pony mares, at 260-320 days gestation undergoing abdominal surgery to implant fetal and maternal vascular catheters. Materials and methods Pre-anaesthetic medication with intravenous (IV) acepromazine (30 µg kg-1), butorphanol (20 µg kg-1) and detomidine (10 µg kg-1) preceded induction of anaesthesia with detomidine (10 µg kg-1) and ketamine (2 mg kg-1) IV Maternal arterial blood pressure was measured directly throughout anaesthesia and arterial blood samples were taken at 20-minute intervals for measurement of blood gases and plasma concentrations of cortisol, glucose and lactate. Anaesthesia was maintained with an IV infusion of detomidine (0.04 mg mL-1), ketamine (4 mg mL-1) and guaiphenesin (100 mg mL-1) (DKG) for 140 minutes. Oxygen was supplied by intermittent positive pressure ventilation (IPPV) adjusted to maintain PaCO2 between 5.0 and 6.0 kPa (38 and 45 mm Hg), while PaO2 was kept close to 20.0 kPa (150 mm Hg) by adding nitrous oxide. Simultaneous fetal and maternal blood samples were withdrawn at 90 minutes. Recovery quality was assessed. Results DKG was infused at 0.67 ± 0.17 mL kg-1 hour-1 for 1 hour then reduced, reaching 0.28 ± 0.14 mL kg-1 hour-1 at 140 minutes. Arterial blood gas values and pH remained within intended limits. During anaesthesia there was no change in heart rate, but arterial blood pressure decreased by 10%. Plasma glucose and lactate increased (10-fold and 2-fold, respectively) and cortisol decreased by 50% during anaesthesia. Fetal umbilical venous pH, PO2 and PCO2 were 7.34 ± 0.06, 5.8 ± 0.9 kPa (44 ± 7 mm Hg) and 6.7 ± 0.8 kPa (50 ± 6 mm Hg); and fetal arterial pH, PO2 and PCO2 were 7.29 ± 0.06, 4.0 ± 0.7 kPa (30 ± 5 mm Hg) and 7.8 ± 1.7 kPa (59 ± 13 mm Hg), respectively. Surgical conditions were good but four ponies required a single additional dose of ketamine. Ponies took 60 ± 28 minutes to stand and recovery was good. Conclusions and clinical relevance Anaesthesia produced with DKG was smooth while cardiovascular function in mare and fetus was well preserved. This indicates that DKG infusion is suitable for maintenance of anaesthesia in pregnant equidae.