@article{gluck_pratt-phillips_2024, title={Influence of iron supplementation on insulin and glucose dynamics in horses}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae234.747}, abstractNote={Abstract Iron is an essential micromineral involved in various physiological functions such as oxygen transport. The National Research Council’s Nutrient Requirements of Horses has iron requirements set at 400 mg iron daily for a 500 kg horse at maintenance; however, a survey found that Thoroughbreds consumed well over the daily requirement at 3,900 mg of iron from hay and grain alone. Additionally, a previous study has found a correlation between hyperinsulinemia and increased ferritin, an indicator of iron body stores. Therefore, the objective of the present study was to determine the effects of iron supplementation on body iron stores as well as insulin and glucose dynamics. It was hypothesized that iron supplementation would influence body iron stores and insulin and glucose responses. Mixed-breed geldings [n = 12; 558.9 ± 74.4 kg body weight (BW)] were housed individually for the study. Horses were fed 2% of their BW in grass hay and an iron-free vitamin mineral supplement, consuming an average of 600 mg of iron daily for the first 28 d (Hay Phase). Horses were then assigned to continue on the hay diet (CTRL; n = 4) or an iron-supplemented diet (IRON; n = 8), in which an oral iron supplement was given daily in the form of ferrous sulfate, with IRON horses consuming an average of 4,000 mg of iron daily for 28 d (Supplement Phase). Oral sugar tests (OSTs) were performed at the beginning of the study as well as the end of each phase, using a 0.45 mL/kg of BW Karo Light Syrup dose to determine insulin response, with jugular venous samples taken prior to the dose and 60 min after. All statistical analysis was performed in GraphPadPrism Version 10.2.0 (GraphPad Software, Boston, MA), using analysis of variance for repeated measures and correlation analysis. All OSTs throughout the study had a significant time effect (P < 0.05) for both insulin and glucose. There was a time X treatment trend (P = 0.1) for insulin during the Supplement Phase and when using multiple comparisons, insulin response was significantly greater (P < 0.0007) at 0 versus 60 min in IRON horses. Although there was no correlation found between 60-min insulin and ferritin concentrations in both IRON and CTRL horses, mean ± SD insulin and ferritin in the IRON group were 23.6 ± 10 uU/mL and 570 ± 195.8 ng/mL, respectively, while in the CTRL group these were 12.7 ± 2.9 uU/mL and 453 ± 31.1 ng/mL, respectively. In conclusion, iron supplementation with an inorganic form at 10 times the daily requirement appears to result in increased insulin responses as well as body iron stores. Further research needs to determine if feeds naturally enriched in iron impact glucose metabolism.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Gluck, Cassandra R. and Pratt-Phillips, Shannon E.}, year={2024}, month={Sep}, pages={658–658} }
 @article{gluck_bowman_layton_stuska_maltecca_pratt-phillips_2023, title={3 A comparison of the equine fecal microbiome within different horse populations}, volume={124}, ISSN={0737-0806}, url={http://dx.doi.org/10.1016/j.jevs.2023.104305}, DOI={10.1016/j.jevs.2023.104305}, abstractNote={The equine fecal microbiome may vary across horse populations due to the diversity of the habitual diet. The purpose of this study was to assess and compare the microbial population of different horse populations, specifically the differences between feral versus domesticated populations. Samples were collected from 3 different populations of horses: horses from the Shackleford Banks (n = 24), a feral horse population living on the Outer Banks of North Carolina who eat native grasses such as Spartina marsh and island grasses; horses from the NCSU Equine Educational Unit (n = 18) that are predominantly kept on cool season mixed pastures and may be supplemented with hay and concentrates from time to time; and finally, privately owned horses (n = 36) that are fed mixed diets consisting of pasture, hay and concentrates. Horses were monitored and samples were collected immediately following a void by swabbing the middle of the void. Swabs were placed in a tube containing 500 uL DNA/RNA shield (Zymo Research, Irvine, CA) and were sent to the Emerging Technology Center (Purina Animal Nutrition, Gray Summit, MO) where they were stored at −80°C and then the V3 and V4 regions of the 16S rRNA gene were sequenced following the Illumina 16S Protocol (San Diego, CA). Samples were processed, filtered and trimmed through DADA2 using the QIIME2 pipeline. Statistical analysis was performed in R(Version 4.1.1) and a P-value of ≤0.05 was considered significant. After processing to eliminate samples with low sampling depth (<20,085), 78 total samples across the 3 populations were analyzed. For the results, when testing α diversity with Shannon's Index, a Kruskal-Wallis rank sum test revealed a significant difference between all populations (P = 0.01). There was a visual distinction between the Shackleford Banks population compared with the others when utilizing Bray-Curtis to assess β diversity. Additionally, an apparent significant difference between all populations using the PERMANOVA UniFrac test (P < 0.001) was observed. The 3 most predominant bacterial phylum seen across all populations were Firmicutes, Bacteroidetes and Spirochaetes. The top 5 phyla observed in the Shackleford Banks population were Firmicutes, Bacteroidetes, Spirochaetes, Kiritimatiellaeota and Fibrobacteres. Based on the results, there is a distinctive separation in microbial diversity between these horse populations, specifically between the Shackleford Banks horses versus the NCSU and privately owned horses. This separation is likely due to the habitual diet of these specific horse populations influencing the composition of their microbiome within the hindgut.}, journal={Journal of Equine Veterinary Science}, publisher={Elsevier BV}, author={Gluck, C. and Bowman, M. and Layton, J. and Stuska, S. and Maltecca, C. and Pratt-Phillips, S.}, year={2023}, month={May}, pages={104305} }
 @article{gluck_fellner_mcleod_stuska_pratt-phillips_2023, title={An in-Vitro Model of the Equine Fecal Microbiome to Assess How Horse Population Affects Fermentation Following a Starch Challenge}, volume={101}, ISSN={["1525-3163"]}, url={http://dx.doi.org/10.1093/jas/skad068.048}, DOI={10.1093/jas/skad068.048}, abstractNote={Abstract
               The use of an in-vitro model of the equine microbiome is beneficial to assess how fermentation patterns differ based on a horse populations’ habitual diet. The purpose of this study was to determine the in-vitro fermentation patterns of the microbial community within different horse populations before and following a starch challenge. Fecal samples were taken from three different populations of horses: horses from the Shackleford Banks, a North Carolina feral horse population living on native grasses; horses from the NCSU Equine Educational Unit that are predominantly kept on cool season mixed pastures, though may be supplemented with hay and concentrates when warranted; and privately owned horses that were fed mixed diets consisting of grass hay, concentrates and some pasture. Horses were monitored and fecal samples were collected immediately following a void and were stored on dry ice and frozen until analysis. Fecal samples from individual horses were pooled to form a representative sample for each population and mixed with an anaerobic medium to prepare an inoculum. The inoculum was placed into bottles containing either a treatment substrate of alfalfa (A) or of alfalfa and starch (AS). Bottles were capped, purged with CO2 and placed in a water bath at 39°C to incubate for 0, 2, 4 or 24 hours. Culture samples were processed to measure methane and short chain fatty acids (SCFAs; acetate, propionate, butyrate and other isoacids) using gas chromatography. Results were analyzed using the Proc Mixed procedure in SAS to compare the effects of horse population, time and treatment. Methane was significantly greater after 24 hours within all populations with AS, as the inoculum compared with A alone (P = 0.03). Propionate was greater for AS (molar percentage, mean ± standard deviation; 2.21 ± 4.97%) versus the A treatment (11.95 ± 4.97%, P = 0.02). Acetate concentrations were significantly (P < 0.001) greater within the A treatment in the Shackleford and NCSU horses (60.31 ± 10.3% and 62.18 ± 11.47%, respectively) compared with the AS treatment (59.09 ± 11.21% and 59.77 ± 8.85%, respectively). Privately owned horses showed similar values of acetate concentration when comparing the treatment of A (63.42 ± 10.13%) versus AS (63.55 ± 10.77%). Butyrate concentrations were greater in the Shackleford Banks and NCSU horses (13.16 ± 1.92% and 2.64 ± 4.22%, respectively) compared with the privately owned horses (10.96 ± 2%). Isoacids were greater in the Shackleford Banks horses (10.19 ± 4.15%) than the NCSU horses (9.87 ± 3.98%) and the privately owned horses (9.52 ± 3.53%; P< 0.0001). It appears that fermentation of starch differs between these horse populations, likely due to their habitual diet.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Gluck, Cassandra R. and Fellner, Vivek and McLeod, Sarah and Stuska, Sue and Pratt-Phillips, Shannon E.}, year={2023}, month={May} }
 @article{munjizun_gluck_walston_high_hunter_pratt-phillips_2023, title={Effect of weight carriage on work effort in horses}, volume={19}, ISSN={["1755-2559"]}, url={https://doi.org/10.1163/17552559-20220066}, DOI={10.1163/17552559-20220066}, abstractNote={Abstract
Excessive adiposity in horses is associated with equine metabolic syndrome and laminitis, and additional weight due to fat accumulation may cause further stress on the horse. This study aimed to determine the effect of additional weight carriage on work effort in horses, as estimated by changes in heart rate (HR) and body temperature (Temp). Eight mature mixed-breed horses were paired based on body size in a randomised crossover study. Each day tested a pair of horses with one horse carrying additional weight (15% of body weight; to represent approximately 3 body condition scores) and the other horse serving as a control, with treatments reversed the following week. Heart rate was determined before adding the weight, after a 2 h period of stall rest (prior to the exercise bout), and at the end of a 34 min exercise challenge of walking and trotting on an automated exerciser. Temp was recorded prior to exercise and after the horses were removed from the exerciser. Two-way ANOVA was conducted to determine the effect of exercise and weight carriage on HR and Temp, and paired t-tests were used to compare differences in HR and Temp pre- and post-exercise. HR increased with exercise () and was higher following exercise in horses carrying additional weight (). Exercise increased Temp () and the difference in Temp was greater in the weight-carrying group (). This study documents the effect of weight carriage that could be imposed with body fat, in addition to the known health detriments of adiposity.}, number={5}, journal={COMPARATIVE EXERCISE PHYSIOLOGY}, author={Munjizun, A. and Gluck, C. and Walston, L. and High, K. and Hunter, R. and Pratt-Phillips, S.}, year={2023}, month={Dec}, pages={511–516} }
 @article{gluck_williams_pratt-phillips_2023, title={Performance analysis of show jumping rounds at a national pony competition}, volume={19}, ISSN={["1755-2559"]}, url={https://doi.org/10.1163/17552559-20220064}, DOI={10.1163/17552559-20220064}, abstractNote={Abstract
Performance analysis is utilised by coaches and athletes to identify areas to work on in training and to identify strengths in athlete performance in various sports. However, performance analysis is not commonly used within equestrian sports. The purpose of this study was to evaluate minors and their ponies competing in show jumping at a national pony competition to see if course variables affected performance. All jumping rounds were watched online. Type of faults (e.g. rails, refusals, time faults, fall of horse and or rider), type of fence (e.g. vertical, oxer), approach angle, section of the course where fault(s) occurred and round time were recorded. Spearman’s Correlation assessed if round time was correlated to total faults and a series of Kruskal-Wallis analyses determined if significant differences in faults occurred between sections of the course, where these existed, post hoc tests established where differences occurred between rounds. There was no significant difference in total faults across the 4 rounds of competition and no meaningful correlation between round time and total faults (r = 0.34; ). There were no differences between fence type and faults although more faults occurred at verticals (51.7%, n = 46 faults at verticals versus 48.3%, n = 43 at oxers; ). Faults were more likely to occur during the final quarter of the course (32.6%, n = 29) when compared to the first quarter (23.6%, n = 21; ). These results showed that faults were more likely to occur in the final quarter of a round. The information gained from this performance analysis could be beneficial to inform training or riding strategies, especially when preparing for a competition.}, number={5}, journal={COMPARATIVE EXERCISE PHYSIOLOGY}, author={Gluck, C. and Williams, J. and Pratt-Phillips, S.}, year={2023}, month={Dec}, pages={399–405} }
 @inproceedings{gluck_pratt-phillips_2021, title={65  Survey regarding the perception of prebiotics/probiotics amongst North Carolina horse owners or leasers}, volume={100}, url={http://dx.doi.org/10.1016/j.jevs.2021.103528}, DOI={10.1016/j.jevs.2021.103528}, abstractNote={A survey was conducted to evaluate how prebiotics and probiotics are used and perceived among horse owners or leasers in North Carolina. This survey was deemed exempt from full review by the NCSU Institutional Review Board. Qualtrics was used to develop the survey and it allowed for multiple horses to be represented by one owner. There were 14 questions in the survey and these included information about if the respondent resided in North Carolina and their county, number of horses owned, information about the feed offered to their horses and the owner's use and perception of supplemental prebiotics and probiotics. The survey was shared to 7 different Facebook groups representing horse owners and equestrians of North Carolina, potentially reaching up to 63,300 members, though it is likely that many horse owners were members of multiple groups or were inactive. Therefore, neither true reach nor the response rate could be accurately determined, though a total of 501 surveys were completed. Of these, 52.9% reported offering feeds containing prebiotics or probiotics while 22.0% were unsure if their feed contains them. In addition, 32.7% of respondents offered a supplemental prebiotic or probiotic. Gastric/hindgut ulcers (39.8%) and colic (28.1%) were the most common health concerns reported by the owners. The majority of responders (82.7%) believe prebiotics and/or probiotics benefit their horse's gut health. When respondents were asked to comment on their experience regarding the use of prebiotics and probiotics, common words used included “health,” “beneficial,” “difference,” “happy,” “ulcer” and “diarrhea,” implying that prebiotics and probiotics are perceived to be beneficial by these horse owners and may be helping manage some of their equine's conditions. Further, 68.2% of the respondents believe that horse owners should consider implementing prebiotics and/or probiotics into a horse's daily feeding program. In conclusion, the results of this survey indicate that these horse owners are frequently using prebiotics and/or probiotics and are seeing beneficial changes to their horse's gut health. Since most prebiotic/probiotic efficacy studies are conducted on research animals, more work is required to establish the use and effectiveness of prebiotics and probiotics in privately owned horses.}, booktitle={Journal of Equine Veterinary Science}, author={Gluck, C. and Pratt-Phillips, S.}, year={2021}, month={May}, pages={103528} }