Temperature regulation in horses involves physiological processes that maintain the animal's core body temperature within a narrow, optimal range despite external environmental changes. Horses, being homeothermic animals, rely on mechanisms such as sweating, respiration, and blood flow adjustments to dissipate excess heat or conserve warmth. These thermoregulatory processes are influenced by factors such as exercise, humidity, and ambient temperature. Variations in temperature can affect a horse's performance, health, and overall well-being. This page aggregates peer-reviewed research studies and scholarly articles that explore the mechanisms, effects, and implications of temperature regulation in equine physiology.
Smith KM, Maxwell L, Gull T, Payton ME, Gilmour MA.To establish the effect of storage in a constant-rate infusion (CRI) pump on the sterility and stability of voriconazole 1% solution. Methods: Nine vials of voriconazole (Vfend(®) I.V.) 1% solution were prepared. Approximately half of each solution was used to prime a commercially available CRI pump with attached subpalpebral lavage system (CRI/SPL unit) with the remaining solution stored in the commercial glass vial. Three CRI/SPL units and their three corresponding vials were stored at one of three temperatures: 23 °C, 33 °C, and 40 °C. The CRI pumps ran for 7 days, and the vials were st...
Grint NJ, Beths T, Yvorchuk K, Taylor PM, Dixon M, Whay HR, Murrell JC.To evaluate a mechanical nociceptive threshold (MNT) testing device in the donkey, and to investigate the influence of potential confounders on MNTs generated. Methods: Prospective, randomised. Methods: Sixteen castrated male donkeys aged 4-9 years, weighing 105-170 kg. Methods: Mechanical nociceptive thresholds were measured using an actuator with three pins placed on the dorsal aspect of the distal limb, connected to a force meter. The pins (surface area 15 mm(2) ) were extruded onto the limb by pressurising an air-filled syringe, until the MNT force (when foot-lift was observed) or 25 N (cu...
Haeussler S, Luepke M, Seifert H, Staszyk C.In equine practice, teeth corrections by means of motorized grinding systems are standard procedure. The heat resulting from that treatment may cause irreparable damage to the dental pulp. It has been shown that a 5.5°C temperature rise may cause severe destruction in pulp cells. Hence, the capability to continuously form secondary dentine is lost, and may lead, due to equine-typical occlusal tooth abrasion, to an opening of the pulp cavity.To obtain reliable data on the intra-pulp increase in temperature during corrective treatments, equine cheek teeth (CT) were modified in a way (occlusal s...
Holcomb KE, Tucker CB, Stull CL.Provision of shade is recommended by best practice guidelines for horses living in hot, sunny environments despite a lack of research focused on potential benefits. We found in a previous study that horses without access to shade showed greater rectal temperature (RT), respiration rate (RR), and skin temperature (SK) and exhibited more sweat than horses that were completely shaded. Yet not known is whether horses will choose to stand in the shade when given a choice of areas with and without this resource. Our objective was to assess horse preference for shaded and unshaded areas in the hot an...
Khoshtariya DE, Dolidze TD, Shushanyan M, van Eldik R.Horse muscle myoglobin (Mb) was tightly immobilized at Au-deposited ~15-Å-thick mixed-type (1:1) alkanethiol SAMs, HS-(CH₂)₁₁-COOH/HS-(CH₂)₁₁-OH, and placed in contact with buffered H₂O or D₂O solutions. Fast-scan cyclic voltammetry (CV) and a Marcus-equation-based analysis were applied to determine unimolecular standard rate constants and reorganization free energies for electron transfer (ET), under variable-temperature (15-55 °C) and -pressure (0.01-150 MPa) conditions. The CV signal was surprisingly stable and reproducible even after multiple temperature and pressure cycl...
Longland AC, Barfoot C, Harris PA.The effects of different water-soaking treatments on removal of water-soluble carbohydrates (WSC), WSC constituents and protein from four UK hays were determined. Hays were soaked in water for up to 16 hours at mean temperatures of 8°C, 16°C, in hot tap water (initially 49°C) or agitated and rinsed in clean water at 16°C. Initial hay WSC contents ranged from 154 to 216 g/kg dry matter. Losses of WSC from hays after 16 hours soaking at 8°C, 16°C, 16°C plus agitation and 49°C averaged 28, 46, 49 and 44 per cent, respectively. Corresponding percentage losses of fructan were 16, 37, 39 and...
van Eps AW, Pollitt CC, Underwood C, Medina-Torres CE, Goodwin WA, Belknap JK.Prophylactic digital hypothermia reduces the severity of acute laminitis experimentally but there is no evidence for its efficacy as a treatment once lameness has already developed. Objective: To investigate the therapeutic effects of digital hypothermia, applied after the onset of lameness, in an experimental acute laminitis model. Methods: Randomised, controlled (within subject), blinded, experimental trial. Methods: Eight Standardbred horses underwent laminitis induction using the oligofructose model. Once lameness was detected at the walk, one forelimb was continuously cooled (CRYO), with ...
Alberghina D, Casella S, Giannetto C, Marafioti S, Piccione G.Serum protein electrophoresis (SPE) is a technique that could be considered one of the most useful diagnostic aids available to the clinician. The effect of storage time and temperature on the total proteins and electrophoretic fractions (albumin, α1-, α2-, β1-, β2-, and γ-globulins) was assessed in 24 healthy horses. All samples, collected by jugular vein puncture, were centrifuged and divided into 4 aliquots. The 1st aliquot was analyzed within 3 h from collection (time 0), the 2nd was refrigerated at +4°C for 24 h, the 3rd was refrigerated at +4°C for 48 h, and the last was frozen at...
Hartwig FP, Lisboa FP, Hartwig FP, Monteiro GA, Maziero RR, Freitas-Dell'Aqua CP, Alvarenga MA, Papa FO, Dell'Aqua JA.During the cooling process, sperm may suffer irreversible damage that compromises the fertility rate. Incorporating cholesterol-loaded cyclodextrin (CLC) represents a strategy to increase sperm resistance at low temperatures; however, high levels of cholesterol in the cell membrane can interfere with sperm capacitation. The goals of this study were to determine the CLC concentration and cooling temperature that produce optimal kinetic parameters and viability of sperm from stallions identified as bad coolers (BCs) and good coolers (GCs), as well as the effect of adding CLC on the occurrence of...
Bartolomé E, Sánchez MJ, Molina A, Schaefer AL, Cervantes I, Valera M.The aims of this study were, first, to evaluate eye temperature (ET) with infrared thermography and heart rate (HR) to measure stress in horses during show jumping competitions and their relationship with competition results, and second, to evaluate the influence of different extrinsic and intrinsic factors of the horse on the stress measurements analysed. One hundred and seventy-three Spanish Sport Horses were analysed for ET and HR, and these measurements were taken 3 h before the competition, just after and 3 h after it. Two interval measurements were also assessed for each parameter. Posit...
Brinkmann L, Gerken M, Riek A.Water is an essential nutrient necessary to support life, and adequate water supply is crucial for animal survival and productivity. The present study was designed to determine seasonal changes in the water metabolism of horses under outdoor conditions. Total body water (TBW) and total water intake (TWI) of 10 adult Shetland pony mares were estimated at monthly intervals for 14 mo by using the deuterium dilution technique. During the last 4 mo, 5 ponies were fed restrictively to simulate natural feed shortage in winter, and 5 ponies served as controls. The TBW (kg) was closely related to body ...
Oldenhof H, Gojowsky M, Wang S, Henke S, Yu C, Rohn K, Wolkers WF, Sieme H.The aim of this study was to determine how different membrane-permeable and -impermeable cryoprotective agents modulate tolerance of stallion sperm to osmotic stress and stabilize membranes during cryopreservation. Special emphasis was on hydroxyl ethylene starch (HES), which exposes cells to minimal osmotic stress due to its large molecular weight. Percentages of motile sperm post-thaw were found to be similar when glycerol, sucrose, and HES were used at their optimal concentrations. Percentages of plasma membrane intact sperm after return to isotonic medium were highest for HES. Fourier tran...
Tinkler SH, Couëtil LL, Constable PD.The stability of total CO2 concentration (ctCO2) in plasma is influenced by storage temperature and handling during sample processing. Conflicting information exists regarding the stability of ctCO2 in equine plasma over time, and the effect of centrifugation on the measured value for plasma ctCO2 is unclear. Objective: To determine plasma ctCO2 stability over 5 days when equine blood is collected into Vacutainer tubes, centrifuged within 30 min of collection, and stored at 4 degrees C; and to determine whether a delay in centrifugation increases the rate at which plasma ctCO2 decreases over t...
McDowell KJ, Moore ES, Parks AG, Bush LP, Horohov DW, Lawrence LM.The hypotheses that endophyte (Neotyphodium coenophialum)-infected tall fescue (TF) seed causes vasoconstriction in horses in vivo and that ground seed would cause more pronounced vasoconstriction than whole seed were tested. Ten horses each received 1 of 3 treatments: endophyte-free ground (E-G; n = 4 horses) seed, endophyte-positive whole (E+W; n = 3) seed, or endophyte-positive ground (E+G; n = 3) seed. There were two 14-d periods, P1 and P2. During P1, animals were adapted to a concentrate (0.2% BW, as fed, twice daily) and alfalfa cubes. During P2, the seed was mixed into the concentrate ...
Paz S, Malkinson D, Green MS, Tsioni G, Papa A, Danis K, Sirbu A, Ceianu C, Katalin K, Ferenczi E, Zeller H, Semenza JC.In the summer of 2010, Europe experienced outbreaks of West Nile Fever (WNF) in humans, which was preceded by hot spells. The objective of this study was to identify potential drivers of these outbreaks, such as spring and summer temperatures, relative humidity (RH), and precipitation. Methods: Pearson and lag correlations, binary and multinomial logistic regressions were used to assess the relationship between the climatic parameters and these outbreaks. Results: For human morbidity, significant (<0.05) positive correlations were observed between a number of WNF cases and temperature, with...
Cathcart MP, Love S, Sutton DG, Reardon RJ, Hughes KJ.Analyses of exhaled breath (EB) and exhaled breath condensate (EBC) are non-invasive modalities for assessing the lower airways but these methods have not been applied to Thoroughbred racehorses in training. The aims of this study were to determine whether EB and EBC could be obtained from Thoroughbred racehorses in the field and to investigate the effects of exercise per se and during different ambient temperatures and humidity on exhaled concentrations of nitric oxide (eNO), carbon monoxide (eCO) and EBC pH. EB and EBC samples were obtained from 28 Thoroughbred racehorses pre- and post-exerc...
Montgomery L, Elliott SB, Adair HS.To (1) determine the temperature change in equine tendon and muscle during therapeutic ultrasound and (2) develop guidelines for treating horses for muscular or tendinous injury using therapeutic ultrasound. Methods: Experimental, in vivo study. Methods: Adult horses (n = 10). Methods: Thermistors were inserted in the superficial and deep digital flexor tendons (SDFT and DDFT) of the thoracic limbs of 10 adult horses. On the left, 3.3 MHz therapeutic continuous ultrasound was done for 10 minutes at an intensity of 1.0 W/cm(2) and for the right thoracic limb at 1.5 W/cm(2). Thermistors were pla...
Ransom JI, Hobbs NT, Bruemmer J.Abiotic inputs such as photoperiod and temperature can regulate reproductive cyclicity in many species. When humans perturb this process by intervening in reproductive cycles, the ecological consequences may be profound. Trophic mismatches between birth pulse and resources in wildlife species may cascade toward decreased survival and threaten the viability of small populations. We followed feral horses (Equus caballus) in three populations for a longitudinal study of the transient immunocontraceptive porcine zona pellucida (PZP), and found that repeated vaccinations extended the duration of in...
Westermann S, Buchner HH, Schramel JP, Tichy A, Stanek C.To assess effects of camera angle and distance on measurement and reproducibility of thermographically determined temperatures of the distolateral aspect of the forelimbs in horses. Methods: Evaluation study. Methods: 10 adult horses. Methods: Thermographic images of both forelimbs were obtained at 3 times during the day (replicates 1, 2, and 3); maximum surface temperature over 1 region (distolateral aspect of the third metacarpal bone and metacarpophalangeal joint) was measured. Standard images were obtained every 5 minutes for 1 hour with the camera positioned at an angle of 90° and a dist...
Westermann S, Stanek C, Schramel JP, Ion A, Buchner HH.Current literature suggests that thermographic imaging of horses should be performed in a draught-free room. However, studies on the effect of airflow on determined temperature have not been published. Objective: To investigate effects of airflow on thermographically determined temperature of horses' forelimbs; to assess the relationship of wind velocity, rectal temperature, ambient temperature and humidity. Methods: Thermographic images were obtained for the forelimbs of 6 horses in a draught-free room. Three replicates (R) with defined wind velocities (R1, 0.5-1.0 m/s; R2, 1.3-2.6 m/s; a...
Zhao Y, Ma S, Sun Y, Huang Y, Deng Y.To identify a thermophilic bacterium from horse manure to degrade cellulose efficiently, and to enrich microbial resources producing cellulolytic ethanol by co-culturing with thermophilic ethanol producing bacterium. Methods: We used Hungate anaerobic technique to isolate a strain named as HCp from horse manure mixed culture; its phylogeny was identified through 16S rDNA sequencing. Enzymatic assays were determined using DNS method. Results: The isolated HCp cells were straight with rods size of(0.35-0.50) microm x (2.42-6.40) microm, in the form of single or paring. This strain belongs to a s...
Toth B, Aleman M, Brosnan RJ, Dickinson PJ, Conley AJ, Stanley SD, Nogradi N, Williams CD, Madigan JE.To test the hypothesis that application of a rope restraint device would result in behavioral, electroencephalographic, and humoral changes consistent with sleep and analgesia in neonatal foals. Methods: 8 healthy neonatal foals. Methods: Following acclimatization to experimental conditions, each foal underwent a series of assessments before and during or at the end of a period of restraint via application of a restraint device (soft linen rope). Assessments included measurements of heart and respiratory rates, rectal temperature, and circulating β-endorphin and steroid hormone concentrations...
Casella S, Piccione D, Ielati S, Bocchino EG, Piccione G.The aim of this study was to assess the anion transport in equine erythrocytes through the measurement of the sulfate uptake operating from band 3 using different experimental temperatures and buffer solutions. Blood samples of six clinically healthy horses were collected via jugular vein puncture, and an emochrome-citometric examination was performed. The blood was divided into four aliquots and by centrifugation and aspiration the plasma and buffy coat were carefully discarded. The red blood cells were washed with an isosmotic medium and centrifuged. The obtained cell suspensions were incuba...
Wallsten H, Olsson K, Dahlborn K.Clipping the winter coat in horses is done to improve heat dissipation during exercise and make grooming easier. It is often combined with blanketing to keep the horse warm. The aims of the present study were to investigate how clipping and the use of blankets affect thermoregulation during exercise and recovery in horses. Methods: One Gotland pony, one New Forest pony, and one warm-blooded horse exercised one after the other on a 6450 m long track. The horses walked, trotted and cantered according to a predetermined scheme, which took about 50 minutes including three stops. The scheme was rep...
Mawyer JD, Cavinder CA, Vogelsang MM, Sigler DH, Love CC, Brinsko SP, Blanchard TL, Varner DD, Arnold CE, Teague S, Gordon RK.Stallions (n = 8) were implanted with a thermal sensory device in the muscle of the neck and the subcutaneous tissue of the scrotum and then assigned to either a nonexercise (Non-EX; n = 4) or exercise (EX; n = 4) group. A motorized equine exerciser was used to work EX stallions 30 min/d for 4 d/wk during a 12-wk period from July through October 2010. Temperatures (subcutaneous scrotal, intramuscular neck, and rectal) were recorded at 0, 22, and 30 min after the start of exercise, as well as 60 and 120 min post-exercise. Hourly ambient temperature and relative humidity data were also obtained....
Kennedy SA, Constable PD, Sen I, Couëtil L.To determine effects of syringe type and storage conditions on blood gas and acid-base values for equine blood samples. Methods: Blood samples obtained from 8 healthy horses. Methods: Heparinized jugular venous blood was equilibrated via a tonometer at 37°C with 12% O(2) and 5% CO(2). Aliquots (3 mL) of tonometer-equilibrated blood were collected in random order by use of a glass syringe (GS), general-purpose polypropylene syringe (GPPS), or polypropylene syringe designed for blood gas analysis (PSBGA) and stored in ice water (0°C) or at room temperature (22°C) for 0, 5, 15, 30, 60, or 120 ...
Krumrych W, Skórzewski R, Malinowski E.The aim of this study was to determine the effect of duration and temperature of sample storage on whole blood chemiluminescence measurement results. Venous blood from 18 clinically healthy Polish half-bred horses aged 4 to 11 years were used in the study. Luminol dependent chemiluminescence (CL) was used to measure neutrophil oxygen metabolism in whole blood. Blood samples were examined for spontaneous CL and stimulated by a surface receptor stimulus as well as extra-receptor stimulus. The assay was performed in two parallel experimental sets with samples stored at 4 and 22 °C, respectively....
Reesink HL, Divers TJ, Bookbinder LC, van Eps AW, Soderholm LV, Mohammed HO, Cheetham J.To compare effects of 3 methods of topically applied cold treatment (cryotherapy) on digital laminar and venous temperatures in horses. Methods: 9 healthy adult Thoroughbreds. Methods: Thermocouples were placed in palmar digital veins and digital laminae of both forelimbs of horses. Three methods of cryotherapy were applied to the distal aspects of the limbs: wader boot (63-cm-tall vinyl boot filled with ice and water [ice slurry]), ice bag (5-L fluid bag filled with ice slurry), and a gel pack boot (boot containing frozen gel packs). Gel packs and ice slurries were replenished every hour duri...
Gomes RG, Andrade ER, Lisboa LA, Ciquini A, Barreiros TR, Fonseca NA, Seneda MM.The objective was to evaluate the efficiency of phosphate-buffered saline (PBS) and Minimum Essential Medium (MEM) during the transport of equine preantral and antral follicles at various temperatures and incubation interval. Equine ovaries (n = 10) from an abattoir were cut into 19 fragments; one was immediately fixed in Bouin's solution (control) and the other fragments were placed in PBS or MEM solution at 4, 20, or 39 °C for 4, 12, or 24 h. After the respective incubation periods, all fragments were fixed in Bouin's solution for 24 h and then submitted to standard histologic analysis. In ...
Scarlet D, Budik S, Aurich C.A new device for storage and shipping of cell cultures--the Petaka G3 cell management device--was tested for its applicability for cooled-storage of equine semen. Semen from three stallions was processed with EquiPro extender either without antibiotics (three ejaculates per stallion) or with gentamicin (250 mg/l; three ejaculates per stallion). Semen was either stored at five (anaerobic conditions) or 15 °C (aerobic conditions) in syringes or cell culture devices. Total and progressive motility, as well as membrane integrity of spermatozoa, were evaluated from days 1 to 7 after collection wit...
Ousey JC, McArthur AJ, Rossdale PD.Metabolic rates, rectal temperatures and respiratory quotients (RQ) were determined during the first 24 h post partum in Thoroughbred and pony foals and in relation to environmental temperature. Both breeds had high metabolic rates (greater than 200 W/m2) during the first hour post partum when they were wet and shivering; by 4 to 24 h values were fairly steady at about 153 and 105 W/m2 for Thoroughbred and pony foals, respectively. At birth, rectal temperature was lower in Thoroughbred foals than in pony foals; values increased during the first hour, and then decreased. At 24 h of age, both br...
Trigg LE, Lyons S, Mullan S.The development of exertional heat illness (EHI) is a health, welfare and performance concern for racehorses. However, there has been limited multivariable assessment of the possible risk factors for EHI in racehorses, despite such information being vital for regulators to effectively manage the condition. Consequently, this study aimed to identify the risk factors associated with the occurrence of EHI in Thoroughbred racehorses and assess the ability of the risk factor model to predict the occurrence of EHI in racehorses to assist in early identification. Runners at British racecourses record...
Morozova L, Haezebrouck P, Van Cauwelaert F.The thermal denaturation of Ca(2+)- and apo-forms of equine lysozyme was followed by using far and near UV circular dichroism and intrinsic fluorescence methods. The difference found between the temperature dependence of the ellipticity at 222 nm and 287 nm, which show two stages in the thermal transition, and those at 228 nm and 294 nm, which indicate only one stage over a wide range of temperatures reflects that different subdivisions of the protein molecule are characterized by a different stability, cooperativity and pathway of denaturation. The first transition, reflected in the increase ...
Adler DM, Cornett C, Damborg P, Verwilghen DR.Local anaesthetics (LAs) are frequently used for diagnostic procedures in equine veterinary practice. The objective of this study was to investigate the physico-chemical stability and bacterial contamination of bupivacaine, lidocaine and mepivacaine used for lameness examinations in horses. The LAs were stored in 12 different groups at different temperatures (-18 °C to 70 °C), light intensities and in common veterinary field conditions for up to 16 months. The pH, presence of bacterial contamination and concentrations of LAs and methylparaben (a preservative present in lidocaine) were de...
Foreman JH, Benson GJ, Foreman MH.Horses generate considerable internal heat burdens when exercising. Although common practice for a trainer or groom to place a wet blanket or towel on the dorsum of a hot horse post exercise, there are no data supporting the efficacy of this cooling method. Objective: To test the hypothesis that a pre-moistened blanket designed with a multilayered breathable fabric would enhance heat loss in horses post exercise. Methods: Eight treadmill-trained horses performed a standardised exercise test (SET) weekly for 3 weeks, with 3 different recovery treatments administered randomly. Pulmonary artery t...
Brinsko SP, Rowan KR, Varner DD, Blanchard TL.This study was conducted to compare the cooling rates and storage temperatures within equine semen transport containers exposed to different ambient temperatures, and to evaluate the ability of these containers to preserve spermatozoal motility following 24 h of storage under these conditions. In Experiment 1, nonfat dried milk solids, glucose, sucrose, equine semen extender was divided into seven 40-mL aliquots and loaded into seven different semen transport containers: Equitainer I, Equitainer II, Equitainer III, ExpectaFoal, Bio-Flite, Lane STS, and Equine Express. After containers were loa...
Alberghina D, Casella S, Giannetto C, Marafioti S, Piccione G.Serum protein electrophoresis (SPE) is a technique that could be considered one of the most useful diagnostic aids available to the clinician. The effect of storage time and temperature on the total proteins and electrophoretic fractions (albumin, α1-, α2-, β1-, β2-, and γ-globulins) was assessed in 24 healthy horses. All samples, collected by jugular vein puncture, were centrifuged and divided into 4 aliquots. The 1st aliquot was analyzed within 3 h from collection (time 0), the 2nd was refrigerated at +4°C for 24 h, the 3rd was refrigerated at +4°C for 48 h, and the last was frozen at...
Varner DD, Blanchard TL, Meyers PJ, Meyers SA.A breeding trial was conducted to evaluate the effect of in vitro storage time and temperature on fertilizing capacity of equine spermatozoa. Semen obtained from one stallion and diluted with skim milk-glucose extender was used to artificially inseminate 45 estrussynchronized mares. The mares were assigned to one of three treatment groups (15 mares per group): 1) insemination with fresh semen (collected within 0.5 h of use), 2) insemination with semen stored for 24 h at 20 degrees C or 3) insemination with semen stored for 24 h at 5 degrees C. The mares were inseminated daily during estrus, fr...
Mawyer JD, Cavinder CA, Vogelsang MM, Sigler DH, Love CC, Brinsko SP, Blanchard TL, Varner DD, Arnold CE, Teague S, Gordon RK.Stallions (n = 8) were implanted with a thermal sensory device in the muscle of the neck and the subcutaneous tissue of the scrotum and then assigned to either a nonexercise (Non-EX; n = 4) or exercise (EX; n = 4) group. A motorized equine exerciser was used to work EX stallions 30 min/d for 4 d/wk during a 12-wk period from July through October 2010. Temperatures (subcutaneous scrotal, intramuscular neck, and rectal) were recorded at 0, 22, and 30 min after the start of exercise, as well as 60 and 120 min post-exercise. Hourly ambient temperature and relative humidity data were also obtained....
Diaw M, Salgado RM, Canesin HS, Gridley N, Hinrichs K.Intracytoplasmic sperm injection (ICSI) is an important tool for equine embryo production in both clinical and research settings. In clinical ICSI programs, immature equine cumulus-oocyte complexes (COCs) are often collected at the mare's location and shipped to the ICSI laboratory. To simplify shipment and aid scheduling of subsequent procedures, COCs can be held overnight at room temperature (∼22 °C) before placement into maturation culture, with no detrimental effect on meiotic or developmental competence. A recent study indicated that it might be possible to hold COCs overnight at col...
Burke MJ, Tomlinson JE, Blikslager AT, Johnson AL, Dallap-Schaer BL.Continuous digital cryotherapy experimentally prevents development and reduces severity of sepsis-associated laminitis. A sleeve style ice boot where ice is in direct contact with the skin, and water drains from the boot is being used clinically for distal limb cryotherapy. The degree of cooling achieved by this boot is unknown. Objective: Evaluate skin and lamellar cooling after application of the ice sleeve in healthy horses, and the same horses during an endotoxaemia model. Methods: Prospective study, crossover design. Methods: In eight healthy horses thermocouples were inserted into dorsal...
Lemon AV, Goddard A, Hooijberg EH.The accessibility of thromboelastography (TEG) to general practitioners is limited by short sample storage times (30 minutes) and storage temperatures (20-23°C). Objective: We aimed to evaluate the stability of canine and equine citrated blood samples when stored for extended periods of time, both at room temperature (RT) (20-23°C) and refrigerator temperature (FT) (2-7.5°C). Methods: Citrated whole blood samples from healthy dogs and horses (n = 10 for each) were stored for 30 minutes (baseline) at RT before TEG analysis. Baseline values for TEG variables R, K, α, MA, LY30, and LY60 w...
Shawaf T, Al Mubarak A, Eidi H, El-Bahr SM.Influence of heat or cold stress in sedated animals is unclear and requires further investigations. The present study aimed to evaluate the season's effects on some clinical, hematological parameters and blood cortisol level in sedated Arabian horses with xylazine. Therefore, seven Arabian horses were used to investigate heart and respiratory rates, and capillary refill time and serum cortisol level were recorded before (0) and at 5, 15, 60, and 180 minutes postsedation. Heparinized venous samples were collected before (0) and 3 hours postsedation for analysis of hematological analysis. Arte...
Müller A, Glüge S, Vidondo B, Wróbel A, Ott T, Sieme H, Burger D.Prediction of impending foaling is highly desirable as early intervention may improve mare and foal outcomes. However, monitoring the peripartum mare is a time-consuming challenge for breeders and many foaling prediction systems have limitations. "Heating up" of the mare is empirically used by breeders as a sign of upcoming parturition in mares. The purpose of this study was to investigate if an increase in skin temperature shortly before parturition is detectable and to determine whether such physiological changes could be an additional valuable parameter to predict foaling. For that, 56 foal...
Wong JW, Selvam A, Zhao Z, Yu SM, Law AC, Chung PC.Composting sewage sludge alone would reduce the decomposition efficiency due to free limited porosity in sludge. To alleviate this, the use of horse stable straw bedding waste (HSB) was evaluated as a co-composting material with sewage sludge in a 10 tonnes day(-1) in-vessel composter for a period of 7 days before curing in a static aeration pile. Sludge was mixed with HSB at 1 : 1.5 (HSL) and 1 : 2.9 (LSL) on a fresh weight basis. After a composting period of 56 days, both mixing ratios demonstrated to be feasible with LSL having a better organic decomposition and a shorter time to reach matu...
Albrizio M, Lacalandra GM, Volpe S, Nicassio M, Cinone M.Heat Shock Proteins are chaperones primary involved in the repair of cellular damages induced by temperature. The harmful effect of temperature on the male gonad is well known, on the contrary knowledge on the effects of the environment on semen quality are still insufficient. The aim of this paper was to learn more about the role of HSPs and the environment in modulating the physiology of equine male gonads. We showed a detailed analysis of equine semen characteristic and the expression level of three HSPs (60-70-90) over a one-year period analyzing the effects of temperature and humidity and...
Bedford SJ, Gowdy HL, Hinrichs K.This study was designed to compare the effects of different media and containers on longevity of motility of spermatozoa during in vitro incubation at 38 degrees C in either air or 5% CO2 atmosphere. Three ejaculates were collected from each of 4 stallions. The media tested were skim milk-glucose, modified Krebs/Ringer and Hank's salts solution for incubation in an air atmosphere, and modified Krebs/Ringer and Brackett and Oliphant (BO) defined medium for incubation in a 5% CO2 atmosphere. All samples were incubated in 5-mL borosilicate glass tubes filled with 3 mL of extended spermatozoa, 5-m...
Johnson AL.Studies were conducted to characterize circulating concentrations of prolactin, thyroxine (T4) and triiodothyronine (T3) relative to season and the estrous cycle, and to evaluate the ability of thyrotropin-releasing hormone (TRH) to induce prolactin secretion in the horse mare. The increase in serum prolactin following the iv injection of 0, 5, 50 and 500 micrograms TRH was dose-related, while all three doses of TRH induced a significant and comparable increase in serum T4. Seasonal variations in serum prolactin were directly correlated (P less than .001) with changes in photoperiod (r = .80) ...
Hine L, Laven RA, Sahu SK.To compare the variation in rectal temperature measurement by digital, mercury and ethanol thermometers in cattle, horses and sheep. Methods: Seven different makes of thermometer (four digital, two mercury, and one ethanol; (n=27) were tested individually in a calibrated water bath to identify whether there was an effect of thermometer make on recorded temperature. In addition, rectal temperatures of four cattle, four sheep and four horses were recorded using the same thermometers, by seven persons, with each person being assigned to one thermometer make. Results: In the water bath test, mean ...
Smith JE, Barnes AL, Maloney SK.Body temperature can be a useful measure of how well the horse responds to thermal challenges of exercise and environment. Currently there is little information available about how body temperature changes throughout an endurance ride, and no nonsurgical methods to evaluate internal temperature of exercising horses during prolonged periods and during long distances. Objective: To develop and test a nonsurgical method, using temperature loggers, of continuously recording internal temperature during exercise and over an extended period. Methods: Loggers were inserted transcervically into the ute...
Palmer SE.Ten clinically healthy adult horses were examined with the portable infrared thermometer at ambient temperatures of 5, 15, and 25 C to evaluate the thermal response of limbs of the horse to variations of ambient temperature. Limb surface temperature varied in direct proportion to changes in the ambient temperature, with considerable variation occurring among individual horses, especially at the lower temperatures. Areas of proximal parts of the limbs were more resistant to temperature variation than were distal parts. Ambient temperature had a statistically significant, but clinically unimport...
Arriola J, Foote RH.Because microfloral content of stallion semen tends to be high, and strains may be resistant to commonly used antibiotics, amikacin was tested with stallion semen and compared with bull semen. Nine ejaculates to stallion semen were incubated at 37 C in egg yolk-tris extender for 0, 2, 4, 6, 8 and 10 h in the presence of amikacin concentrations of 0, 50, 100, 250, 500, 1,000 and 10,000 microgram/ml, with penicillin and penicillin-streptomycin as controls. Averaged over all incubations, spermatozoal motility was 44, 48, 49, 46, 45, 45 and 19%, for increasing concentrations of amikacin, compared ...
Verdegaal EJMM, Delesalle C, Caraguel CGB, Folwell LE, McWhorter TJ, Howarth GS, Franklin SH.OBJECTIVE To evaluate use of a telemetric gastrointestinal (GI) pill to continuously monitor GI temperature in horses at rest and during exercise and to compare time profiles of GI temperature and rectal temperature. ANIMALS 8 Standardbred horses. PROCEDURES Accuracy and precision of the GI pill and a rectal probe were determined in vitro by comparing temperature measurements with values obtained by a certified resistance temperature detector (RTD) in water baths at various temperatures (37°, 39°, and 41°C). Subsequently, both GI and rectal temperature were recorded in vivo in 8 horses over...
Pan LG, Forster HV, Kaminski RP.We assessed in ponies the adequacy of using rectal (Tre) rather than arterial temperature (Tar) under conditions common to ventilatory control experiments, i.e., CO2 breathing, thermal stress, and particularly exercise. We were interested in whether, and to what extent, Tar-Tre differences could lead to errors in arterial blood gas corrections. At control environmental temperatures (Ta) of 5 degrees C in the winter and 21 degrees C in the summer, Tar and Tre (37.1 degrees C) did not differ (P greater than 0.05). Elevating winter or summer Ta by 10-18 degrees C for 2-days or lowering summer Ta ...
Deane JC, Dagleish MP, Benamou AE, Wolf BT, Marlin D.To evaluate the consistency of partial pressures (P) of arterial oxygen (aO(2)), arterial carbon dioxide (aCO(2)) and pH measurements in equine carotid arterial blood samples taken into syringes made from three different materials and stored at room temperature or placed in iced water for measurement at three different times. Methods: Prospective observational study over 19 days. Methods: Four clinically normal Thoroughbred or Thoroughbred-cross horses (three geldings, one mare, mean age 6.25 years, range 5-7 years). Methods: Identical blood samples were taken on two separate occasions from th...
Zakari FO, Avazi DO, Ayo JO.The objective of the present study was to evaluate the effect of the depth of insertion and environmental parameters on the rectal temperature (RT) in donkeys during the hot-dry season in a tropical savannah zone of Nigeria. The experimental subjects were comprised of thirty donkeys divided into three groups based on age: group I, 10 foals (40.67 ± 2.20 kg; 1.50 ± 0.02 months); group II, 10 yearlings (91.53 ± 0.54 kg; 1.51 ± 0.01 years); and group III, 10 adults (140 ± 0.71 kg; 8.03 ± 0.06 years). Each group was divided into 5 male and 5 female donkeys. Measurements of the RT were ...
Nie GJ, Wenzel JG.Hypoosmotic swelling (HOS) is used for assessing plasma membrane function and fertilizing capacity of human spermatozoa. However, HOS solutions and methodologies have not been evaluated specifically for assessing stallion spermatozoa. The objective of this study was to identify a HOS solution and assay conditions specifically for stallions that would maximize spermatozoal plasma membrane swelling. The HOS solutions and assay conditions, including incubation time (15 to 180 min), temperature (25 degrees vs 37 degrees C), and total number of cells examined (100, 200 or 500) were evaluated. Assay...
Esteves Trindade PH, de Camargo Ferraz G, Pereira Lima ML, Negrão JA, Paranhos da Costa MJR.This study aimed to investigate the use of maximum eye surface temperature (EST), recorded by infrared thermography, as an indicator of physical fitness in ranch horses. Data collection was carried out with 16 horses by recording six physical fitness biomarkers (EST, respiratory rate, creatine kinase activity [CK], and concentrations of total serum protein, plasmatic cortisol, and lactate) before and after a regular working day. We also recorded heart rate during the exercise, exercise duration, average velocity, distance traveled, and air temperature and humidity. The variation between the sa...
Hosaka Y, Ozoe S, Kirisawa R, Ueda H, Takehana K, Yamaguchi M.The aim of this study was to clarify whether matrix metalloproteinases (MMP-2 and -9: gelatinases) and pro-inflammatory cytokines [tumor necrosis factor (TNF) alpha and interleukin (IL)-1beta] are induced by heat in tendon tissue in vitro and to test the hypothesis that heat exposure causes tendinocytes to synthesize pro-inflammatory cytokines and that synthesis of these cytokines, in turn, leads to up-regulation of synthesis of gelatinases. Isolated tendinocytes from equine superficial digital flexor tendons were cultured and all experiments were performed on cells passaged 3 or 4 times. In t...
Fintl C, Hudson NP, Handel I, Pearson GT.Slow waves are rhythmic pacemaker currents generated by the gastrointestinal pacemaker cells, the interstitial cells of Cajal, and represent the rate-limiting step for small intestinal smooth muscle contractions. Therefore, factors that affect slow wave activity may also influence contractile activity. It is not known how temperature changes may influence slow wave activity in the horse. This could be of relevance during colic surgery if cooling of exposed intestine resulted in reduced slow wave activity potentially exacerbating post operative ileus. Objective: To evaluate the effect of temper...
