Topic:Calcium
Calcium is a mineral that is essential for various physiological processes in horses, including bone development, muscle function, and nerve transmission. It is a critical component of the equine diet and is involved in maintaining skeletal integrity and supporting metabolic functions. Calcium levels in horses are regulated through dietary intake, absorption in the gastrointestinal tract, and hormonal control mechanisms involving the parathyroid hormone and vitamin D. Imbalances in calcium levels can lead to health issues such as metabolic bone disease or hypocalcemia. This page compiles peer-reviewed research studies and scholarly articles that explore the metabolism, dietary requirements, and health implications of calcium in equine nutrition and physiology.
Enriched Pathways of Calcium Regulation, Cellular/Oxidative Stress, Inflammation, and Cell Proliferation Characterize Gluteal Muscle of Standardbred Horses between Episodes of Recurrent Exertional Rhabdomyolysis. Certain Standardbred racehorses develop recurrent exertional rhabdomyolysis (RER-STD) for unknown reasons. We compared gluteal muscle histopathology and gene/protein expression between Standardbreds with a history of, but not currently experiencing rhabdomyolysis (N = 9), and race-trained controls (N = 7). Eight RER-STD had a few mature fibers with small internalized myonuclei, one out of nine had histologic evidence of regeneration and zero out of nine degeneration. However, RER-STD versus controls had 791/13,531 differentially expressed genes (DEG). The top three gene ontology (GO) enriched ...
[Is alfalfa hay an alternative to meadow hay in equine nutrition?]. Roughage alternatives for equine nutrition must be found due to the increasing climatic challenges. The aim of this study was to examine the nutrient composition and feed hygiene of alfalfa hay in comparison to meadow hay and to investigate the acceptance, weight development and faecal quality of broodmares fed alfalfa hay. The feed used was examined for nutrient content and hygiene status according to the standards of the Verband Deutscher Landwirtschaftlicher Untersuchungs- und Forschungsanstalten (VDLUFA). Twenty adult pregnant warmblood mares were fed in two groups (n=10) with a defined am...
Short Communication: Supplementation with calcium butyrate causes an increase in the percentage of oxidative fibers in equine gluteus medius muscle. Optimal athletic performance requires meeting the energetic demands of the muscle fibers, which are a function of myosin ATPase enzymatic activity. Skeletal muscle with a predominant oxidative metabolism underlies equine athletic success. Sodium butyrate, a short-chain fatty acid, can affect muscle fiber composition in pigs. To determine if a similar scenario exists in horses, 12 adult Thoroughbred geldings (7.4 ± 0.6 yr of age; mean ± SEM) were fed 16 g of calcium butyrate (CB) or an equivalent amount of carrier (CON) daily for 30 d in a crossover design. Middle gluteal muscle biopsies were...
In vitro anti-trypanosomal effect of ivermectin on Trypanosoma evansi by targeting multiple metabolic pathways. High cytotoxicity and increasing resistance reports of existing chemotherapeutic agents against T. evansi have raised the demand for novel, potent, and high therapeutic index molecules for the treatment of surra in animals. In this regard, repurposing approach of drug discovery has provided an opportunity to explore the therapeutic potential of existing drugs against new organism. With this objective, the macrocyclic lactone representative, ivermectin, has been investigated for the efficacy against T. evansi in the axenic culture medium. To elucidate the potential target of ivermectin in T. ev...
Serum bone metabolism biomarkers in healthy filies and colts from weaning until one year of age. This study aimed to investigate the serum concentration of osteocalcin (OC), parathyroid hormone (PTH), calcitonin (CT), calcium (Ca), phosphorus (P), alkaline phosphatase (ALP) and acid phosphatase (AP) in healthy-weaned-foals from 8 months of age until the first year of life. Moreover, the correlation of investigated parameters and foals' age, as well as the relationship between the serum values of PTH and the other markers of bone remodeling were assessed. From 20 foals (10 fillies, 10 colts), blood samples were monthly collected (from 8 to 12 months of age, T1-T5) and the concentration o...
The role of bicarbonate in the modulation of capacitation, spontaneous acrosome reaction and motility of equine fresh and frozen spermatozoa. In this study, we defined the composition of the culture medium that yield a significant percentage of alive and functional equine spermatozoa during enough time before artificial insemination. The effects of sodium bicarbonate were analyzed in fresh and frozen semen in respect to sperm viability, capacitation, spontaneous acrosome reaction and several kinetic parameters such as total motility, progressive motility, VCL, VSL, ALH, BCF, LIN. Moreover, employing Bayk-6844 and Nifedipine, the involvement of L-type voltage-gated calcium channels in the modulation of intracellular calcium concentra...
Effect of Lentinula edodes on Morphological and Biochemical Blood Parameters of Horses. Shiitake mushrooms have been highly regarded as possessing enormous nutritive and medicinal values. No clinical studies have yet investigated the effect of shitake supplementation on the health of horses. The aim of this study was to evaluate the effect of shiitake mushroom supplementation on the morphological and biochemical blood properties in horses. A total of 17 adult horses were divided into two groups: supplemented and control. The supplemented group was fed 60 g of shiitake mushrooms per day for 5 months. Blood samples were collected in five sessions. Blood morphological analysis showe...
Metabolic Disorders Associated with Renal Disease in Horses. This article overviews metabolic disorders associated with renal disease. Included is a discussion of the pathophysiology, clinical signs, and treatment of hyperchloremic metabolic acidosis associated with renal tubular acidosis. Conditions affecting the central nervous system including uremic encephalopathy and hyponatremic encephalopathy secondary to renal disease are presented. Finally, a discussion of the unique features of calcium and phosphorus homeostasis in horses is provided with special emphasis on a recently described syndrome of calcinosis and calciphylaxis of unknown etiology.
Alginate encapsulation of stallion sperm for increasing storage stability. The aim of this study was to establish an alginate encapsulation procedure for stallion sperm, and investigate if sperm encapsulation enhances longevity during cold storage and survival after cryopreservation. First, biocompatibility of the compounds needed for encapsulation was tested and factors determining capsule structure were identified. Sperm encapsulation was realized either by depositing droplets (20 µL) of sperm solution supplemented with barium or calcium chloride (10 mM) in alginate solution (0.25%, w/v), or by adding sperm-alginate droplets in solution containing barium or calc...
Treatment of primary hyperparathyroidism in a Miniature Horse using chemical ablation of abnormal parathyroid tissue localized by 3-phase computed tomography. A 15-year-old Miniature Horse mare with persistently increased plasma calcium (total and ionized) and serum parathyroid hormone concentrations was presented for suspected primary hyperparathyroidism. Ultrasonography of the thyroid region identified an enlarged heterogeneous mass axial to the right thyroid lobe suggestive of an enlarged parathyroid gland, which was further confirmed using sestamibi nuclear scintigraphy and 3-phase computed tomography. Percutaneous ultrasound-guided ethanol ablation of the mass, a method not previously described in the horse, was performed under general anesthes...
Influences of the Seasons of the Year and Physiographic Regions on the Levels of Calcium, Copper and Zinc in the Hoof Capsule of Foals Pre- and Postweaning Raised in Native Pasture. This study evaluated the levels of calcium (Ca), copper (Cu) and zinc (Zn) in the hoof of Criollo foals, pre- and postweaning, correlating them with the concentrations of these inorganic chemical compounds in soil and pasture in the different seasons of the year. We used 41 preweaning foals and 28 postweaning foals. Seventeen forage samples were collected in four seasons, later 10 soil samples per property in five distinct physiographic regions (Santa Maria, Dilermando de Aguiar, Jaguarão, Arroio Grande and Pelotas). There was variability in Ca, Cu and Zn concentrations in the hoof foal betwe...
Energy and mineral metabolism of peripartum mares and foals of the Quarter Horse breed. Several studies have demonstrated variations in peripartum blood biochemical analytes used to monitor the health status of mares and their foals of different breeds. Objective: We aimed to characterize the physiologic changes of peripartum energy and mineral metabolism in healthy Quarter Horse mares and their neonatal foals. Methods: Blood samples were initially collected from 17 mares on days 60 and 30 prepartum, and from mares and their foals on the day of parturition (after colostrum ingestion), and on days 15, 30, and 60 postpartum. The serum concentrations of calcium, phosphorus, magnesiu...
Sarcoplasmic Reticulum from Horse Gluteal Muscle Is Poised for Enhanced Calcium Transport. We have analyzed the enzymatic activity of the sarcoplasmic reticulum (SR) Ca2+-transporting ATPase (SERCA) from the horse gluteal muscle. Horses are bred for peak athletic performance yet exhibit a high incidence of exertional rhabdomyolysis, with elevated levels of cytosolic Ca2+ proposed as a correlative linkage. We recently reported an improved protocol for isolating SR vesicles from horse muscle; these horse SR vesicles contain an abundant level of SERCA and only trace-levels of sarcolipin (SLN), the inhibitory peptide subunit of SERCA in mammalian fast-twitch skeletal muscle. Here, we re...
Bicarbonate-Stimulated Membrane Reorganization in Stallion Spermatozoa. Classical in vitro fertilization (IVF) is still poorly successful in horses. This lack of success is thought to be due primarily to inadequate capacitation of stallion spermatozoa under in vitro conditions. In species in which IVF is successful, bicarbonate, calcium, and albumin are considered the key components that enable a gradual reorganization of the sperm plasma membrane that allows the spermatozoa to undergo an acrosome reaction and fertilize the oocyte. The aim of this work was to comprehensively examine contributors to stallion sperm capacitation by investigating bicarbonate-induced m...
Studies of Peculiar Mg-Containing and Oscillating Bioapatites in Sheep and Horse Teeth. New types of biological apatites have been discovered in molar sheep and horse teeth and are divided in two types. In the first and more general type, the release of Mg ions is parallel to the changes in composition of apatite leading to a final stoichiometric ratio of Ca to P ions, going from dentin depth towards the boundary of enamel with air. Inside dentin, another apatite sub-types were discovered with alternating layers of Mg-rich and C-rich apatites. The approximate formal stoichiometric relationships for these peculiar types of bioapatites are suggested. We identified two kinds of ion-...
Investigations on the Effects of Different Calcium Supply Exceeding the Requirements on Mineral Serum Concentrations and Bone Metabolism in Young Warmblood Stallions. Since mineral supplements for horses commonly contain macro minerals, although the requirement for such is usually covered by roughage-based diets, the aim of this study was to investigate the effects of different dietary calcium levels on mineral serum concentrations and bone metabolism. The trial was conducted in 30 young warmblood stallions (2-3 years) that were divided into two groups for a five-month feeding trial. The groups were fed a hay- and oat-based diet and were either supplied with high (Ca-High) or moderate (Ca-Moderate) calcium excess. While in Ca-High calcium supply was about 2...
Limited added value of negative pressure wound therapy compared with calcium alginate dressings for second intention healing in a noncontaminated and contaminated equine distal limb wound model. Distal limb wounds in horses often show aberrant healing due to a slow inflammatory response. In human medicine, negative pressure wound therapy (NPWT) is used for the treatment of chronic wounds with a similar inflammatory response. Objective: To compare the effect of NPWT to calcium alginate dressings on the healing of (non) contaminated equine distal limb wounds. Methods: Controlled experiment. Methods: Circular wounds were created on the left and right dorsomedial metacarpus of 10 horses. In five horses, the wounds were contaminated with Staphylococcus aureus and Pseudomonas aeruginosa. In...
The G-Protein-Coupled Membrane Estrogen Receptor Is Present in Horse Cryptorchid Testes and Mediates Downstream Pathways. Cryptorchidism in horses is a commonly occurring malformation. The molecular basis of this pathology is not fully known. In addition, the origins of high intratesticular estrogen levels in horses remain obscure. In order to investigate the role of the G-protein-coupled membrane estrogen receptor (GPER) and establish histological and biochemical cryptorchid testis status, healthy and cryptorchid horse testes were subjected to scanning electron microscopy analysis, histochemical staining for total protein (with naphthol blue black; NBB), acid content (with toluidine blue O; TBO), and polysacchar...
Effects of intravenous magnesium sulfate on serum calcium-regulating hormones and plasma and urinary electrolytes in healthy horses. Intravenous magnesium sulfate (MgSO4) is used in equine practice to treat hypomagnesemia, dysrhythmias, neurological disorders, and calcium dysregulation. MgSO4 is also used as a calming agent in equestrian events. Hypercalcemia affects calcium-regulating hormones, as well as plasma and urinary electrolytes; however, the effect of hypermagnesemia on these variables is unknown. The goal of this study was to investigate the effect of hypermagnesemia on blood parathyroid hormone (PTH), calcitonin (CT), ionized calcium (Ca2+), ionized magnesium (Mg2+), sodium (Na+), potassium (K+), chloride (Cl-) ...
Factors affecting intracellular calcium influx in response to calcium ionophore A23187 in equine sperm. Exposure to the calcium ionophore A23187 may present a "universal" sperm treatment for IVF, as it bypasses capacitation pathways. However, success in utilizing A23187 is variable, especially in equine spermatozoa. Notably, albumin is used during A23187 treatment but paradoxically is thought to suppress A23187 action. Essentially no critical data are available on the effects of A23187 and albumin concentrations, ratios, or addition protocols on changes in intracellular calcium ([Ca] ) in any cell type. To determine factors that affect the action of A23187 on [Ca] in equine and murine spermatozo...
Rickets in a Thoroughbred-cross foal: case report and review of the literature. Rickets is a metabolic bone disease associated with failure of endochondral ossification and impaired osteoid mineralization in growing animals. As a consequence, affected individuals can develop gross and microscopic bone malformations. The most common causes of rickets in domestic species include vitamin D and phosphorus deficiency. Rickets has been described in multiple species; however, comprehensive postmortem characterizations with confirmatory histopathology in equids have not been published. A 6-mo-old, Thoroughbred-cross foal was diagnosed with rickets based on gross autopsy findings ...
Evaluation of Medetomidine-Ketamine for Immobilization of Feral Horses in Romania. Feral horses are immobilized for a variety of reasons including population control via contraceptives. Although opioid combinations have been successfully used for immobilization of feral horses, there is a need for combinations using drugs that are more readily available and present less of a human health hazard. We evaluated the chemical immobilization with physiological measurements and blood gas analyses of 91 free-ranging feral horses () remotely immobilized with a combination of 30 mg medetomidine and 775 mg ketamine in a single disposable 6 ml dart. During immobilization, heart rate, re...
Effect of Aerosolised Salbutamol Administration on Arterial Potassium Concentration in Anaesthetised Horses. Aerosolized salbutamol has been associated with hypokalemia in horses undergoing colic surgery. The objective of this study was to evaluate the effect of aerosolized salbutamol on arterial potassium concentration ([K +]) in healthy anaesthetized horses undergoing elective surgery. Anesthetic records were reviewed from healthy adult horses undergoing elective surgery over a 3-year period with two complete sets of arterial electrolyte (sodium [Na +], potassium [K +], chloride [Cl -], calcium [Ca 2+]) concentration measurements. Records were excluded if intra-operative electrolyte supplementation...
Electrolytes and pH of Mammary Gland Secretions Assessments to Detect Impending Parturition and Associations With Placental and Neonate Features in Donkeys. The objectives of this study were to determine (i) the usefulness of serial assessment of mammary gland electrolytes concentrations and correspondent pH to detect impending parturition in jennies; and (ii2) the associations between mammary gland secretions, and gestation length, foal sex, maternal, placental, and foal birth weights. Multiparous jennies (n = 37) were monitored daily from 350 to 355 days of gestation until parturition. The pH of mammary gland secretions was assessed daily with a hand-held device. Aliquots of mammary secretions were frozen daily and then retrospectively assesse...
Modified Proximal Interphalangeal Joint Arthrodesis in a Yearling Filly with an Osseous Cyst-Like Lesion in the Proximal Phalanx. After the medial femoral condyle (MFC), the phalanges are the second most common site for osseous cyst-like lesions (OCLLs). Conservative treatment of phalangeal cysts on the convex surface of proximal phalanx presents a technical problem with access to the stoma of the cyst. Surgical therapy options usually aim to avoid cyst enlargement through drilling or screw placement or to encourage lesion filling with osteoconductive material. This paper describes a case of treatment of the OCLL in a yearling Czech warmblood filly with surgical arthrodesis, together with the packing of the OCLL with cal...
Pathways of calcium regulation, electron transport, and mitochondrial protein translation are molecular signatures of susceptibility to recurrent exertional rhabdomyolysis in Thoroughbred racehorses. Recurrent exertional rhabdomyolysis (RER) is a chronic muscle disorder of unknown etiology in racehorses. A potential role of intramuscular calcium (Ca2+) dysregulation in RER has led to the use of dantrolene to prevent episodes of rhabdomyolysis. We examined differentially expressed proteins (DEP) and gene transcripts (DEG) in gluteal muscle of Thoroughbred race-trained mares after exercise among three groups of 5 horses each; 1) horses susceptible to, but not currently experiencing rhabdomyolysis, 2) healthy horses with no history of RER (control), 3) RER-susceptible horses treated with dant...
Primary Hypoparathyroidism and Recurring Hypocalcemia in a Quarter Horse Gelding-A Case Report. Hypoparathyroidism is an uncommon endocrine disorder in the horse characterized by a transient or permanent parathyroid hormone insufficiency. Hypoparathyroidism is associated with hypocalcemia and hyperphosphatemia, primarily presenting with clinical signs consistent with hypocalcemia. This case report describes clinical presentation and treatment of a horse with severe hypocalcemia due to primary hypoparathyroidism. A 17-year-old, 542 kg Quarter Horse gelding presented for shaking and tremors. Significant findings include generalized muscle fasciculations, synchronous diaphragmatic flutter, ...
Reference Ranges for Hematological and Biochemical Profile of Martina Franca Donkeys. The Martina Franca donkey (MFd) is one of the largest Italian donkey breeds, considered as endangered breed. To support the conservation strategies, knowledge about the physiologic hematological parameters of MFds is needed. The aims of the study were to determine reference value for hematological and major serum parameters in a population of healthy MFds and to estimate the influence of age on these parameters. Eighty-one clinically healthy MFds (17 males and 64 females) in different ages were enrolled: group A (foals, n° 16, animals < 1 year old) group B (young animals, n° 36, from 1 to 3 ...
Abortion and uterine prolapse in a Thoroughbred mare with twin pregnancy: Clinical and laboratory findings and treatment approach. This report presents a case of uterine prolapse in a Thoroughbred mare. The uterine prolapse occurred after abortion of twins in the eighth month of gestation. The prolapsed uterus was bleeding and congested but not damaged. The placenta was still attached to the endometrium. Blood samples were collected for hematology and for estimation of calcium, progesterone and estrogen. The cervix and clitoris were swabbed for bacteriology. The mare showed a decrease in the number of lymphocytes. The concentrations of estrogen and progesterone seemed normal compared with mares that foaled. Pseudomonas ae...
Single Layer Centrifugation Improves the Quality of Fresh Donkey Semen and Modifies the Sperm Ability to Interact with Polymorphonuclear Neutrophils. This study sought to determine whether single layer centrifugation (SLC) of fresh donkey semen with Equicoll has any impact on sperm quality parameters and on the modulation of endometrial reaction following semen deposition using an in vitro model. Seventeen ejaculates from five jackasses were obtained using an artificial vagina and diluted in a skim-milk extender. Samples were either selected through SLC (Equicoll) or non-treated (control). Two experiments were performed. The first one consisted of incubating selected or non-selected spermatozoa at 38 °C for 180 min. Integrity and lipid dis...