Iodine is an essential trace element required for the synthesis of thyroid hormones in horses. These hormones are integral to regulating metabolism, growth, and development. Iodine is typically absorbed from the diet, and its availability can vary depending on soil and forage content. Both iodine deficiency and excess can lead to thyroid dysfunction, resulting in conditions such as hypothyroidism or hyperthyroidism. Monitoring iodine levels is important for maintaining equine health, particularly in breeding and growing horses. This page compiles peer-reviewed research studies and scholarly articles that explore the role, dietary sources, metabolic pathways, and health implications of iodine in equine physiology.
Pimenta J, Dias C, Cotovio M, Saavedra MJ.Considering the increasing antibiotics resistance, there has been a propensity to replace them with antiseptics when it comes to wound management and treatment. Nevertheless, in recent years, there have been reports regarding resistance to antiseptics by some bacterial strains. There is also concern about the environmental impact of these substances. The aim of this study was to compare the antimicrobial efficacy of antiseptics and eucalyptus essential oils on bacterial strains from horse's wounds. We used twelve Escherichia coli, eight Staphylococcus aureus, two Staphylococcus pseudintermediu...
Lopez-Rodriguez MF, Cymbaluk NF, Epp T, Laarveld B, Thrasher M, Card CE.Iodine, thyroxine (T4) and triiodothyronine (T3) are required for normal fetal growth, maturation, and neonatal survival. There is a lack of robust information on iodine levels found in colostrum, milk, and serum of mares and foals after a healthy pregnancy. Our objective was to characterize colostrum, milk, and serum iodine levels in healthy postpartum mares and foals (n = 10) and explore relationships with thyroid hormone concentrations. Colostrum, milk, and jugular blood samples from draft breed mares and foals with an estimated average iodine daily intake of 39 mg per mare during pregnan...
Lopez BS, Hurley DJ, Giancola S, Giguère S, Felippe MJB, Hart KA.The impact of culture conditions on equine monocyte-derived dendritic cells (MoDC) generation has not been fully characterized. We hypothesized that 1) MoDC could be cultured in a commercially available serum-free medium (AIM-V); and 2) that differential culture conditions would influence MoDC viability, yield and phenotype. MoDC generated from adult horses were cultured under variable conditions in a series of experiments. Viability was assessed using trypan blue and propidium iodide staining. Yield was determined by manual hemocytometer counting. Phenotype was assessed by flow cytometric ana...
Gałęcki K, Kowalska-Baron A.In this study, the influence of heavy-atom perturbation, induced by the addition of iodide ions, on the fluorescence and phosphorescence decay parameters of some single tryptophan containing serum albumins isolated from: human (HSA), equine (ESA) and leporine (LSA) has been studied. The obtained results indicated that, there exist two distinct conformations of the proteins with different exposure to the quencher. In addition, the Stern-Volmer plots indicated saturation of iodide ions in the binding region. Therefore, to determine quenching parameter, we proposed alternative quenching model and...
Johnson J, Messier S, Meulyzer M, Vinardell T, Marcoux M, David F.To compare bacterial colonization after diluted iodine tincture or povidone iodine solution for presurgical disinfection of the equine peripodal region. Methods: Complete block design. Methods: Five horses. Methods: Disinfection protocols using iodine tincture or povidone iodine solutions were tested on 5 pairs (n = 10) equine front feet. Iodine tincture was applied to the left feet and povidone iodine to the right feet. Fixed surfaces of the sole, frog, hoof wall, and peripodal skin were swabbed pre-preparation (T0), after a standard pre-disinfection step (T1), after short disinfection wi...
Nemoto M, Bannai H, Tsujimura K, Yamanaka T, Kondo T.Although many disinfectants are commercially available in the veterinary field, information on the virucidal effects of disinfectants against equine group A rotavirus (RVA) is limited. We evaluated the performance of commercially available disinfectants against equine RVA. Chlorine- and iodine-based disinfectants showed virucidal effects, but these were reduced by the presence of organic matter. Glutaraldehyde had a virucidal effect regardless of the presence of organic matter, but the effect was reduced by low temperature or short reaction time, or both. Benzalkonium chloride had the greatest...
Crothers SL, White SD, Ihrke PJ, Affolter VK.Sporotrichosis is an uncommon to rare cutaneous and subcutaneous mycosis of animals and humans caused by the dimorphic fungus Sporothrix schenckii. Twenty-three mammalian cases of sporotrichosis examined between 1987 and 2007 at the University of California, Davis - Veterinary Medical Teaching Hospital, were retrospectively evaluated with regard to the historical, clinical, diagnostic and treatment findings. Cats were the most common species affected (n = 14). In addition, sporotrichosis was diagnosed in four dogs, four horses and a donkey. Six of 23 cases were diagnosed with the localized cut...
Love CC, Thompson JA, Brinsko SP, Rigby SL, Blanchard TL, Lowry VK, Varner DD.Relationships between sperm motility parameters and viability were evaluated using two fluorescent staining techniques in fresh extended semen (fresh and after 24 h storage at 5 degrees C) that had various concentrations of dead sperm added to simulate different levels of viable and nonviable sperm. Both protocols incorporated SYBR-14 and propidium iodide (PI) while the second protocol added the mitochondrial probe JC-1. The relationship between total sperm motility and percent viable sperm was high between staining protocols (r = 0.98). Time (0 h versus 24 h, P<0.0001) and treatment (0, 10, 2...
Worster AA, Lillich JD, Cox JH, Rush BR.A 9-year-old pregnant mare was referred for evaluation of a nonhealing wound of 8 weeks' duration on the lateral aspect of the left forelimb. A soft tissue mass encircled the proximal two thirds of the metacarpus; radiography revealed a moderate periosteal reaction affecting metacarpal bone i.v. Histologic and immunohistochemical examinations revealed eosinophilic granulomatous inflammation and Pythium sp in the soft tissues. The mare was treated for 12 days with antimicrobials, medicated wound dressings, debridement, and i.v. administration of sodium iodide; radiography revealed progression o...
González G, Ventura R, Smith AK, de la Torre R, Segura J.A gas chromatographic-mass spectrometric (GC-MS) procedure for the detection of seventeen non-steroidal anti-inflammatory drugs (NSAIDs) in equine plasma and urine samples is described. The extraction of the compounds from the biological matrix was performed at acidic pH (2-3) with diethyl ether. Ethereal extracts were washed with a saturated solution of sodium hydrogencarbonate (urine) or treated with a solid mixture of sodium carbonate and sodium hydrogencarbonate (plasma). The ethereal extracts were dried and derivatized by incubation at 60 degrees C with methyl iodide in acetone in the pre...
Osame S, Ichijo S.Seven cases of thoroughbred foals kept on a farm in the Hidaka district of Hokkaido showed bilateral thyroid enlargement from 3 or 4 months after birth. Their serum T4 levels were remarkably low, whereas T3 levels were in the normal range. Serum T4 levels were also low in the other clinically normal foals and their dams kept together. Since the iodine content in pasture soil and grass was very low, iodine deficiency was supposed to be the cause of the disease.
Silva CA, Merkt H, Bergamo PN, Barros SS, Barros CS, Santos MN, Hoppen HO, Heidemann P, Meyer H.Excessive iodine supply of at least 700 mg inorganic iodine in foals and of more than 350 mg iodine in pregnant and lactating mares cause a high incidence of goitres in the newborn and disorders in the long leg bones of foals. Elevated phosphorus and alkaline phosphatase content in the blood may indicate a severe disturbance in the bone metabolism. Of 39 pregnant mares 17 aborted and some of the mares also showed goitres. After withdrawal of the iodine supply normalization took place. Foals born more than 6 weeks later showed normal conditions. The goitres in the mares and the high blood level...
van Dyk E, Lange AL.Fifty ml of a 0.2% iodine solution were instilled into the uteri of six mares selected for culling. Biopsy specimens were taken for microscopic examination before the commencement of the experiment and at various times over the course of a year after the single instillation. Severe oedema and haemorrhage was present in the lamina propria of all the post-instillation biopsy specimens. The epithelium showed vacuolisation and necrosis, as well as focal areas of epithelial loss. In some cases hyperplasia or metaplasia was seen. Cell infiltration was characterized by the presence of neutrophils, eo...
Marolt J, Naglić T, Hajsig D.A case of a spontaneous mycokeratitis of a previously injured cornea in a horse is described. The infection was caused by Aspergillus oryzae. After application of Chloramphenicol ophthalmic ointment a corneal clouding was found in the centre which was circularly sharply defined and which - after dispensing Dexamethason-Neomycin eye drops - expanded all over to a purulent keratitis. The demarcated and initially non purulent mycotic lesions largely improved after the application of tincture of iodine, whereas the purulent keratitis could be completely cured only by a lasting treatment with Lugol...
Baker JR, Wyn-Jones G, Eley JL.A brief review of the literature on equine goitre is presented, together with a case of congenital goitre in a foal. This animal showed localised swelling of the neck, hyperextension of the lower limbs and initial difficulty in sucking. The goitre was removed surgically and the hyperextension successfully treated with surgical shoes and bandaging. The cause was probably iodine deficiency coupled with a goitrogen in the diet.
Hintz HF, Kallfelz FA.The effects of overfeeding, calcium-phosphorus imbalance, misuse of supplements and false advertising on equine nutrition are discussed. Overfeeding is known to cause disorders in several species but, although a similar relationship has been suggested on clinical evidence, no controlled trials on horses have been reported. It has also been suggested that overfeeding is a problem only for those horses with a genetic predisposition to skeletal problems. The importance of adequate calcium and phosphorus levels has been known for many years but severe cases of calcium deficiency still occur. Clien...
Doige CE, McLaughlin BG.Hyperplastic goitre was observed in seven newborn foals. Several were weak at birth and died in the first 48 hours of life. Only one foal had myxedema and only three of the seven had obvious enlargement of the thyroid at necropsy. It is suggested that the goitre observed was caused by a dietary deficiency of iodine.
Miquelis R, Simon C.1. The subcellular particles of horse and rat thyroids were fractionated in a B XIV zonal rotor on a non-linear gradient of Ficoll after labelling with radioactive iodine in vitro (horse) or in vivo (rat). In the horse, the resulting fractions were analysed for radioactive iodine, protein and enzymes representative of certain subcellular particles. In the rat, iodine turnover and thyrotrophin stimulation were studied. 2. The population of iodinated particles could be subdivided into three main classes, characterized by differences in beta-galactosidase and acid phosphatase content and position...
Crothers SL, White SD, Ihrke PJ, Affolter VK.Sporotrichosis is an uncommon to rare cutaneous and subcutaneous mycosis of animals and humans caused by the dimorphic fungus Sporothrix schenckii. Twenty-three mammalian cases of sporotrichosis examined between 1987 and 2007 at the University of California, Davis - Veterinary Medical Teaching Hospital, were retrospectively evaluated with regard to the historical, clinical, diagnostic and treatment findings. Cats were the most common species affected (n = 14). In addition, sporotrichosis was diagnosed in four dogs, four horses and a donkey. Six of 23 cases were diagnosed with the localized cut...
Doige CE, McLaughlin BG.Hyperplastic goitre was observed in seven newborn foals. Several were weak at birth and died in the first 48 hours of life. Only one foal had myxedema and only three of the seven had obvious enlargement of the thyroid at necropsy. It is suggested that the goitre observed was caused by a dietary deficiency of iodine.
Lopez-Rodriguez MF, Cymbaluk NF, Epp T, Laarveld B, Thrasher M, Card CE.Iodine, thyroxine (T4) and triiodothyronine (T3) are required for normal fetal growth, maturation, and neonatal survival. There is a lack of robust information on iodine levels found in colostrum, milk, and serum of mares and foals after a healthy pregnancy. Our objective was to characterize colostrum, milk, and serum iodine levels in healthy postpartum mares and foals (n = 10) and explore relationships with thyroid hormone concentrations. Colostrum, milk, and jugular blood samples from draft breed mares and foals with an estimated average iodine daily intake of 39 mg per mare during pregnan...
Nemoto M, Bannai H, Tsujimura K, Yamanaka T, Kondo T.Although many disinfectants are commercially available in the veterinary field, information on the virucidal effects of disinfectants against equine group A rotavirus (RVA) is limited. We evaluated the performance of commercially available disinfectants against equine RVA. Chlorine- and iodine-based disinfectants showed virucidal effects, but these were reduced by the presence of organic matter. Glutaraldehyde had a virucidal effect regardless of the presence of organic matter, but the effect was reduced by low temperature or short reaction time, or both. Benzalkonium chloride had the greatest...
van Dyk E, Lange AL.Fifty ml of a 0.2% iodine solution were instilled into the uteri of six mares selected for culling. Biopsy specimens were taken for microscopic examination before the commencement of the experiment and at various times over the course of a year after the single instillation. Severe oedema and haemorrhage was present in the lamina propria of all the post-instillation biopsy specimens. The epithelium showed vacuolisation and necrosis, as well as focal areas of epithelial loss. In some cases hyperplasia or metaplasia was seen. Cell infiltration was characterized by the presence of neutrophils, eo...
Johnson J, Messier S, Meulyzer M, Vinardell T, Marcoux M, David F.To compare bacterial colonization after diluted iodine tincture or povidone iodine solution for presurgical disinfection of the equine peripodal region. Methods: Complete block design. Methods: Five horses. Methods: Disinfection protocols using iodine tincture or povidone iodine solutions were tested on 5 pairs (n = 10) equine front feet. Iodine tincture was applied to the left feet and povidone iodine to the right feet. Fixed surfaces of the sole, frog, hoof wall, and peripodal skin were swabbed pre-preparation (T0), after a standard pre-disinfection step (T1), after short disinfection wi...
Marolt J, Naglić T, Hajsig D.A case of a spontaneous mycokeratitis of a previously injured cornea in a horse is described. The infection was caused by Aspergillus oryzae. After application of Chloramphenicol ophthalmic ointment a corneal clouding was found in the centre which was circularly sharply defined and which - after dispensing Dexamethason-Neomycin eye drops - expanded all over to a purulent keratitis. The demarcated and initially non purulent mycotic lesions largely improved after the application of tincture of iodine, whereas the purulent keratitis could be completely cured only by a lasting treatment with Lugol...
González G, Ventura R, Smith AK, de la Torre R, Segura J.A gas chromatographic-mass spectrometric (GC-MS) procedure for the detection of seventeen non-steroidal anti-inflammatory drugs (NSAIDs) in equine plasma and urine samples is described. The extraction of the compounds from the biological matrix was performed at acidic pH (2-3) with diethyl ether. Ethereal extracts were washed with a saturated solution of sodium hydrogencarbonate (urine) or treated with a solid mixture of sodium carbonate and sodium hydrogencarbonate (plasma). The ethereal extracts were dried and derivatized by incubation at 60 degrees C with methyl iodide in acetone in the pre...
Baker JR, Wyn-Jones G, Eley JL.A brief review of the literature on equine goitre is presented, together with a case of congenital goitre in a foal. This animal showed localised swelling of the neck, hyperextension of the lower limbs and initial difficulty in sucking. The goitre was removed surgically and the hyperextension successfully treated with surgical shoes and bandaging. The cause was probably iodine deficiency coupled with a goitrogen in the diet.
Hintz HF, Kallfelz FA.The effects of overfeeding, calcium-phosphorus imbalance, misuse of supplements and false advertising on equine nutrition are discussed. Overfeeding is known to cause disorders in several species but, although a similar relationship has been suggested on clinical evidence, no controlled trials on horses have been reported. It has also been suggested that overfeeding is a problem only for those horses with a genetic predisposition to skeletal problems. The importance of adequate calcium and phosphorus levels has been known for many years but severe cases of calcium deficiency still occur. Clien...
Gałęcki K, Kowalska-Baron A.In this study, the influence of heavy-atom perturbation, induced by the addition of iodide ions, on the fluorescence and phosphorescence decay parameters of some single tryptophan containing serum albumins isolated from: human (HSA), equine (ESA) and leporine (LSA) has been studied. The obtained results indicated that, there exist two distinct conformations of the proteins with different exposure to the quencher. In addition, the Stern-Volmer plots indicated saturation of iodide ions in the binding region. Therefore, to determine quenching parameter, we proposed alternative quenching model and...
Silva CA, Merkt H, Bergamo PN, Barros SS, Barros CS, Santos MN, Hoppen HO, Heidemann P, Meyer H.Excessive iodine supply of at least 700 mg inorganic iodine in foals and of more than 350 mg iodine in pregnant and lactating mares cause a high incidence of goitres in the newborn and disorders in the long leg bones of foals. Elevated phosphorus and alkaline phosphatase content in the blood may indicate a severe disturbance in the bone metabolism. Of 39 pregnant mares 17 aborted and some of the mares also showed goitres. After withdrawal of the iodine supply normalization took place. Foals born more than 6 weeks later showed normal conditions. The goitres in the mares and the high blood level...
Miquelis R, Simon C.1. The subcellular particles of horse and rat thyroids were fractionated in a B XIV zonal rotor on a non-linear gradient of Ficoll after labelling with radioactive iodine in vitro (horse) or in vivo (rat). In the horse, the resulting fractions were analysed for radioactive iodine, protein and enzymes representative of certain subcellular particles. In the rat, iodine turnover and thyrotrophin stimulation were studied. 2. The population of iodinated particles could be subdivided into three main classes, characterized by differences in beta-galactosidase and acid phosphatase content and position...
Osame S, Ichijo S.Seven cases of thoroughbred foals kept on a farm in the Hidaka district of Hokkaido showed bilateral thyroid enlargement from 3 or 4 months after birth. Their serum T4 levels were remarkably low, whereas T3 levels were in the normal range. Serum T4 levels were also low in the other clinically normal foals and their dams kept together. Since the iodine content in pasture soil and grass was very low, iodine deficiency was supposed to be the cause of the disease.
Worster AA, Lillich JD, Cox JH, Rush BR.A 9-year-old pregnant mare was referred for evaluation of a nonhealing wound of 8 weeks' duration on the lateral aspect of the left forelimb. A soft tissue mass encircled the proximal two thirds of the metacarpus; radiography revealed a moderate periosteal reaction affecting metacarpal bone i.v. Histologic and immunohistochemical examinations revealed eosinophilic granulomatous inflammation and Pythium sp in the soft tissues. The mare was treated for 12 days with antimicrobials, medicated wound dressings, debridement, and i.v. administration of sodium iodide; radiography revealed progression o...
Lopez BS, Hurley DJ, Giancola S, Giguère S, Felippe MJB, Hart KA.The impact of culture conditions on equine monocyte-derived dendritic cells (MoDC) generation has not been fully characterized. We hypothesized that 1) MoDC could be cultured in a commercially available serum-free medium (AIM-V); and 2) that differential culture conditions would influence MoDC viability, yield and phenotype. MoDC generated from adult horses were cultured under variable conditions in a series of experiments. Viability was assessed using trypan blue and propidium iodide staining. Yield was determined by manual hemocytometer counting. Phenotype was assessed by flow cytometric ana...
Love CC, Thompson JA, Brinsko SP, Rigby SL, Blanchard TL, Lowry VK, Varner DD.Relationships between sperm motility parameters and viability were evaluated using two fluorescent staining techniques in fresh extended semen (fresh and after 24 h storage at 5 degrees C) that had various concentrations of dead sperm added to simulate different levels of viable and nonviable sperm. Both protocols incorporated SYBR-14 and propidium iodide (PI) while the second protocol added the mitochondrial probe JC-1. The relationship between total sperm motility and percent viable sperm was high between staining protocols (r = 0.98). Time (0 h versus 24 h, P<0.0001) and treatment (0, 10, 2...
Pimenta J, Dias C, Cotovio M, Saavedra MJ.Considering the increasing antibiotics resistance, there has been a propensity to replace them with antiseptics when it comes to wound management and treatment. Nevertheless, in recent years, there have been reports regarding resistance to antiseptics by some bacterial strains. There is also concern about the environmental impact of these substances. The aim of this study was to compare the antimicrobial efficacy of antiseptics and eucalyptus essential oils on bacterial strains from horse's wounds. We used twelve Escherichia coli, eight Staphylococcus aureus, two Staphylococcus pseudintermediu...
