Fibrous osteodystrophy due to secondary renal hyperparathyroidism in a senile dog / Osteodistrofia fibrosa decorrente de hiperparatireodismo secundário renal em cão senil

Renal hyperparathyroidism stands out among the complications of kidney disease in dogs due to phosphorus retention with a predisposition to hypocalcemia, parathyroid hormone stimulation with mobilization of calcium from the bones, characterizing fibrous osteodystrophy, unusual in the elderly. The objective was to report it in 12-year-old Labrador with polyuria, polydipsia, and emesis for five months due to maxillary and mandibular volume increase, followed by loosely fixed teeth, and facial deformity. Blood tests showed anemia, thrombocytosis, azotemia, hypoalbuminemia and hyperphosphatemia and urinalysis showed low density, glycosuria, proteinuria, and moderate caudate and transitional epithelial cells. Oral x-rays showed loss of dental bone support and decreased bone radiopacity. Chest radiographs showed decreased density in the ribs and costochondral junction; on the other hand, organs of the cardiorespiratory system showed no changes. The electrocardiogram and echocardiogram did not show impairment. Abdominal ultrasound revealed kidneys with asymmetry, increased echogenicity of the cortical and poorly preserved cortico-medullary definition. Oral histopathology showed intense fibroplasia associated with bone reabsorption. Support therapy was instituted, but the patient died ten days after consultation. Thus, although uncommon in the elderly, fibrous osteodystrophy should be investigated in dogs with advanced-stage chronic kidney disease and, even with conservative therapies, the prognosis is unfavorable.

O hiperparatireoidismo renal destaca-se entre as complicações da doença renal em cães, pela retenção de fósforo com predisposição à hipocalcemia, estimulação de paratormônio com mobilização do cálcio dos ossos, caracterizando a osteodistrofia fibrosa, incomum em idosos. O objetivo foi relatá-la em Labrador de 12 anos com poliúria, polidipsia e vômitos há cinco meses, além de aumento de volume maxilar e mandibular seguido de dentes frouxamente fixados e deformidade facial. Os exames sanguíneos denotaram anemia, trombocitose, azotemia, hipoalbuminemia, hiperfosfatemia, urinálise, baixa densidade, glicosúria, proteinúria e moderadas células caudadas e epiteliais de transição. Pelos raios X orais, houve perda da sustentação óssea dentária e diminuição da radiopacidade óssea. As radiografias de tórax demonstraram diminuição da densidade óssea na região dos arcos costais e junção costocondral; em contrapartida, órgãos do sistema cardiorrespiratório se mostraram sem alterações aparentes. O eletrocardiograma e o ecocardiograma não incidiram comprometimento. O ultrassom abdominal revelou rins com assimetria, aumento da ecogenicidade cortical e definição corticomedular pouco preservada, e a histopatologia oral apontou intensa fibroplasia associada à reabsorção óssea. Foi instituída terapia suporte, mas o paciente veio a óbito 10 dias após a consulta. Assim, mesmo que incomum em idosos, a osteodistrofia fibrosa deve ser investigada em cães com doença renal crônica em estágio avançado, mesmo com as terapias conservadoras, o prognóstico é desfavorável.

Maxillomandibular deformity in a canine with fibrous osteodystrophy secondary to chronic kidney disease

Background: Cases of renal fibrous osteodystrophy are usually associated with nutritional causes, which of renal causesare considered uncommon in dogs. This disorder is characterized by the intense proliferation of fibrous connective tissue inbones, impairing bone stiffness. The aim of this study was to report a case of fibrous osteodystrophy secondary to chronickidney disease in a canine with a “rubber jaw” facial deformity.Case: A 4-year-old male unneutered mongrel dog weighing 5.2 kg had a history of apathy, progressive weight loss andvomiting for one month, and polyuria and polydipsia for more than three months. In addition, the owner complained aboutthe deformed appearance in the muzzle region of the animal, which was evidenced flexibility of the same, with a displacement of the mandible and maxilla on physical examination, similar to the “rubber jaw”. Blood tests revealed macrocyticanemia, elevated total plasma proteins, and lymphopenia-associated neutrophilia, as well as hyperphosphatemia (24 mg/dL), uremia (283.6 mg/dL) and increased creatinine (8.6 mg/dL), ALT (143.2 UI/L) and alkaline phosphatase (3222.2UI/L), while calcium (8.8 mg/dL) and albumin (1.9 g/dL) were decreased. A serological test for visceral leishmaniasis wasalso performed, which was negative. Abdominal ultrasound imaging revealed kidneys with alterations in tissue architecture, increased thickness and complete loss of cortico-medullary relationship, while the parathyroid gland was enlargedand spindle-shaped. Cranial radiography showed marked radiopacity of the bilateral maxillary bones, with destructionof the nasal, turbinate and frontal bones, as well as loosening of the teeth and destruction of the mandibular bone matrix,characterizing an aspect of “rubber jaw”. Based on the history, history and evidence of azotemia, hyperphosphatemia andloss of facial bone density, the diagnosis of fibrous osteodystrophy secondary to chronic kidney...

Maxillomandibular deformity in a canine with fibrous osteodystrophy secondary to chronic kidney disease

Background: Cases of renal fibrous osteodystrophy are usually associated with nutritional causes, which of renal causesare considered uncommon in dogs. This disorder is characterized by the intense proliferation of fibrous connective tissue inbones, impairing bone stiffness. The aim of this study was to report a case of fibrous osteodystrophy secondary to chronickidney disease in a canine with a “rubber jaw” facial deformity.Case: A 4-year-old male unneutered mongrel dog weighing 5.2 kg had a history of apathy, progressive weight loss andvomiting for one month, and polyuria and polydipsia for more than three months. In addition, the owner complained aboutthe deformed appearance in the muzzle region of the animal, which was evidenced flexibility of the same, with a displacement of the mandible and maxilla on physical examination, similar to the “rubber jaw”. Blood tests revealed macrocyticanemia, elevated total plasma proteins, and lymphopenia-associated neutrophilia, as well as hyperphosphatemia (24 mg/dL), uremia (283.6 mg/dL) and increased creatinine (8.6 mg/dL), ALT (143.2 UI/L) and alkaline phosphatase (3222.2UI/L), while calcium (8.8 mg/dL) and albumin (1.9 g/dL) were decreased. A serological test for visceral leishmaniasis wasalso performed, which was negative. Abdominal ultrasound imaging revealed kidneys with alterations in tissue architecture, increased thickness and complete loss of cortico-medullary relationship, while the parathyroid gland was enlargedand spindle-shaped. Cranial radiography showed marked radiopacity of the bilateral maxillary bones, with destructionof the nasal, turbinate and frontal bones, as well as loosening of the teeth and destruction of the mandibular bone matrix,characterizing an aspect of “rubber jaw”. Based on the history, history and evidence of azotemia, hyperphosphatemia andloss of facial bone density, the diagnosis of fibrous osteodystrophy secondary to chronic kidney...(AU)

Metabolic bone diseases in a wild crab-eating hawk and a caboclo hawk in Paraiba

The amount of research on metabolic bone diseases in commercial birds is considerable, however, there is a large gap in the knowledge of these diseases in wild birds. Aspects related to diet are the main factors that cause these diseases, such as: vitamin D deficiency, insufficient calcium intake, or imbalance of calcium and phosphorus in the diet, and problems in the absorption and metabolism of these compounds. This study reports two cases of bone diseases in birds of the order Accipitriformes, which are wild in the state of Paraíba, a crab-eating hawk with rickets, and a caboclo hawk with fibrous osteodystrophy. The diagnosis in both cases was based on macroscopic and microscopic findings. These reports are subsidies for the bird clinic of the order Accipitriformes and for the maintenance of these birds in nurseries and zoos. This study demonstrates the need for further studies to assess whether such cases can be used as indicators of environmental imbalance.

Metabolic bone diseases in a wild crab-eating hawk and a caboclo hawk in Paraiba

The amount of research on metabolic bone diseases in commercial birds is considerable, however, there is a large gap in the knowledge of these diseases in wild birds. Aspects related to diet are the main factors that cause these diseases, such as: vitamin D deficiency, insufficient calcium intake, or imbalance of calcium and phosphorus in the diet, and problems in the absorption and metabolism of these compounds. This study reports two cases of bone diseases in birds of the order Accipitriformes, which are wild in the state of Paraíba, a crab-eating hawk with rickets, and a caboclo hawk with fibrous osteodystrophy. The diagnosis in both cases was based on macroscopic and microscopic findings. These reports are subsidies for the bird clinic of the order Accipitriformes and for the maintenance of these birds in nurseries and zoos. This study demonstrates the need for further studies to assess whether such cases can be used as indicators of environmental imbalance.(AU)

Causes of death of domestic cats in a veterinary hospital of Uberlândia, Minas Gerais state: a retrospective study / Causas de óbito em gatos domésticos em um hospital veterinário de Uberlândia, Minas Gerais: estudo retrospectivo

Cats play an important role as pets in the present society. Thus, the knowledge about their main diseases and causes of death is fundamental to prevent various pathologies. However, when dealing with domestic cats there are very few researches in Veterinary Medicine. The aim of this study is to identify the causes of death of cats through a retrospective study of necropsies in the Animal Pathology Laboratory in the Federal University of Uberlândia (Brazil), in a period of 36 years, in which 350 cat necropsies were conducted. The most frequent causes of death of these animals were digestive system diseases (48 cats ­ 13.71%), and among them, feline hepatic lipidosis was the most frequent etiology (18.75%). The second most affected system was the respiratory (10.86%) and acute pneumonia, pulmonary edema, and diaphragmatic hernia were the main diseases to cause death of cats with some kind of disorder in this system. Other decease causes were rabies, squamous cell carcinoma, fibrous osteodystrophy, fractures and traumatism, hypovolemic shock, and feline lower urinary tract disease. This type of analysis can provide basic information about the most common diseases in felines, contributing with veterinarians as they adopt control and prevention actions against diseases.(AU)

Os gatos apresentam papel relevante como animal de estimação na sociedade atual. Neste sentido, o conhecimento das principais enfermidades e causas de morte desses animais é fundamental para prevenção de várias patologias. No entanto, quanto ao gato doméstico, essas pesquisas ainda são escassas na medicina veterinária. Assim, este trabalho realizou um estudo retrospectivo das causas de morte de gatos registradas das necropsias efetuadas pelo Laboratório de Patologia Animal da Universidade Federal de Uberlândia, em um período de 36 anos, no qual 350 gatos foram necropsiados. As doenças do sistema digestivo foram as mais frequentes (48 gatos ­ 13,71%) e destas, a lipidose hepática foi a etiologia de maior ocorrência (18,75%). O sistema respiratório foi o segundo mais afetado (10,86%), sendo pneumonia aguda, edema pulmonar e hérnia diafragmática as principais doenças deste sistema responsáveis pela morte de gatos. Outras causas de óbito importantes foram raiva, carcinoma de células escamosas, osteodistrofia fibrosa, fraturas e traumatismos, choque hipovolêmico e síndrome urológica felina. Este tipo de análise pode fornecer informações básicas sobre as enfermidades que mais acometem os felinos de uma determinada região, contribuindo para que os profissionais médicos veterinários passem a adotar as respectivas ações de prevenção e controle.(AU)

Causes of death of domestic cats in a veterinary hospital of Uberlândia, Minas Gerais state: a retrospective study / Causas de óbito em gatos domésticos em um hospital veterinário de Uberlândia, Minas Gerais: estudo retrospectivo

Cats play an important role as pets in the present society. Thus, the knowledge about their main diseases and causes of death is fundamental to prevent various pathologies. However, when dealing with domestic cats there are very few researches in Veterinary Medicine. The aim of this study is to identify the causes of death of cats through a retrospective study of necropsies in the Animal Pathology Laboratory in the Federal University of Uberlândia (Brazil), in a period of 36 years, in which 350 cat necropsies were conducted. The most frequent causes of death of these animals were digestive system diseases (48 cats ­ 13.71%), and among them, feline hepatic lipidosis was the most frequent etiology (18.75%). The second most affected system was the respiratory (10.86%) and acute pneumonia, pulmonary edema, and diaphragmatic hernia were the main diseases to cause death of cats with some kind of disorder in this system. Other decease causes were rabies, squamous cell carcinoma, fibrous osteodystrophy, fractures and traumatism, hypovolemic shock, and feline lower urinary tract disease. This type of analysis can provide basic information about the most common diseases in felines, contributing with veterinarians as they adopt control and prevention actions against diseases.(AU)

Os gatos apresentam papel relevante como animal de estimação na sociedade atual. Neste sentido, o conhecimento das principais enfermidades e causas de morte desses animais é fundamental para prevenção de várias patologias. No entanto, quanto ao gato doméstico, essas pesquisas ainda são escassas na medicina veterinária. Assim, este trabalho realizou um estudo retrospectivo das causas de morte de gatos registradas das necropsias efetuadas pelo Laboratório de Patologia Animal da Universidade Federal de Uberlândia, em um período de 36 anos, no qual 350 gatos foram necropsiados. As doenças do sistema digestivo foram as mais frequentes (48 gatos ­ 13,71%) e destas, a lipidose hepática foi a etiologia de maior ocorrência (18,75%). O sistema respiratório foi o segundo mais afetado (10,86%), sendo pneumonia aguda, edema pulmonar e hérnia diafragmática as principais doenças deste sistema responsáveis pela morte de gatos. Outras causas de óbito importantes foram raiva, carcinoma de células escamosas, osteodistrofia fibrosa, fraturas e traumatismos, choque hipovolêmico e síndrome urológica felina. Este tipo de análise pode fornecer informações básicas sobre as enfermidades que mais acometem os felinos de uma determinada região, contribuindo para que os profissionais médicos veterinários passem a adotar as respectivas ações de prevenção e controle.(AU)

Hypertrophic osteopathy associated with systemic granulomatous disease in a horse / Osteopatia hipertrófica associada à doença granulomatosa sistêmica em um equino

A 4-year-old Criollo stallion was presented at the equine clinic of veterinary hospital of the Federal University of Santa Maria, RS, with a 30-day history of progressive weight loss, anemia and swelling of the forelimbs and face. Physical examination revealed that the swelling was firm and had a bone-like consistency, also radiographs showed extensive periosteal proliferation on the forelimb long bones that suggested hypertrophic osteopathy (Marie´s disease). Physical examinations identified no respiratory findings. However, during ultrasound examination, superficial lung disease was identified. The animal was treated with antibiotics and nonsteroidal anti-inflammatory drugs for 12 days. Due to a complete lack of response to this treatment, the horse was euthanized. At necropsy several granulomatous lesions were identified in the thorax, abdomen and testicular tunics. Bony proliferation was evident on many bones of the appendicular skeleton and face. Based on these findings the diagnosis of hypertrophic osteopathy associated with sarcoidosis was established. It is important to perform a thorough clinical examination and include hypertrophic osteopathy in the differential diagnosis of diseases that are accompanied by swelling of the face and limbs as edema from various causes, fibrous osteodystrophy, for example.(AU)

Um garanhão Crioulo, 4 anos de idade, foi atendido na clínica de equinos do hospital veterinário da Universidade Federal de Santa Maria, RS, com histórico de emagrecimento progressivo há 30 dias, anemia e aumento de volume dos membros torácicos e da face. O exame físico revelou que o aumento de volume era firme e apresentava consistência óssea. Radiografias também mostraram extensa proliferação periosteal nos ossos longos dos membros anteriores, o que sugeriu a osteopatia hipertrófica (doença de Marie). Os exames físicos não identificaram alteração respiratória. No entanto, durante o exame ultrassonográfico, foi identificada doença pulmonar superficial. O animal foi tratado com antibióticos e anti-inflamatórios não esteróides durante 12 dias. Devido a uma completa falta de resposta ao tratamento, o cavalo foi sacrificado. Durante a necropsia, várias lesões granulomatosas foram identificadas no tórax, abdômen e túnicas testiculares. Proliferação óssea era evidente em vários ossos do esqueleto apendicular e da face. Com base nestes resultados o diagnóstico de osteopatia hipertrófica associada à sarcoidose foi estabelecido. É importante realizar um exame clínico completo e incluir a osteopatia hipertrófica no diagnóstico diferencial de enfermidades que vêm acompanhadas de aumento de volume da face e dos membros como edema por diversas causas e osteodistrofia fibrosa, por exemplo.(AU)

Doença renal crônica e uremia em gatos domésticos

Esta dissertação de mestrado foi dividida em duas partes, resultando em dois artigos científicos. O primeiro artigo consistiu em um estudo comparativo entre as alterações macroscópicas, histológicas e características imuno-histoquímicas de 25 gatos com doença renal crônica (DRC) com fibrose intersticial. O diagnóstico morfológico de nefrite túbulo intersticial crônica (NTIC) foi o mais comumente observado (20/25) e cinco gatos (5/25) apresentaram doença glomerular primária. Foi observada redução do tamanho dos rins em 22 dos 25 casos e os rins diminuídos de tamanho apresentaram graus mais elevados de fibrose intersticial (p=0.021) e a redução do tamanho renal foi correlacionada à severidade da inflamação crônica (p=0.0039) e da fibrose intersticial (p<0,001). O aspecto macroscópico arredondado dos rins, presente apenas na NTIC foi atribuído à fibrose intersticial, atrofia tubular, obsolescência glomerular e redução da espessura da camada cortical lateralmente ao hilo renal, região compatível com os polos renais. A imunomarcação celular para actina-alfa de músculo liso (-SMA) foi observada em todos os estágios da DRC, demonstrando a importância dos miofibroblastos nos diferentes processos e graus de intensidade da DRC com desenvolvimento de fibrose intersticial. O segundo estudo teve como objetivo determinar a prevalência e os aspectos clínicos da uremia em gatos, além dos aspectos patológicos e a distribuição anatômica das lesões extrarrenais da uremia. No período estudado (janeiro de 2000 a outubro de 2019) foram necropsiados 1.330 gatos, dentre os quais 78 apresentaram lesões extrarrenais de uremia (5,8%). Em 75% dos casos, a azotemia prolongada e uremia foram consequência de doenças renais. A DRC na forma de NTIC foi o processo renal mais comumente observado. As principais lesões extrarrenais de uremia observadas nos gatos foram o edema pulmonar e a gastrite hemorrágica e/ou ulcerativa. Mineralização de tecidos moles e hiperplasia das paratireoides foram achados incomuns, e osteodistrofia fibrosa não foi observada. A apresentação multissitêmica de lesões extrarrenais de uremia foi observada em apenas 24% dos casos, e algumas lesões normalmente encontradas em cães urêmicos não foram observadas nos gatos deste estudo.

This masters dissertation was composed of two different parts, resulting in two scientific articles. The first article consisted of a comparative study between macroscopic, histological and immunohistochemical features changes in 25 cats with chronic kidney disease (CKD) with interstitial fibrosis. The morphological diagnosis of chronic tubular interstitial nephritis (CTIN) was the most commonly observed (20/25) and five cats (5/25) had primary glomerular disease. Reduction of kidney size was observed in 22 of the 25 cases and the reduced kidneys had higher degrees of interstitial fibrosis (p = 0.021) and the reduction in kidney size was correlated with the severity of chronic inflammation (p = 0.0039) and interstitial fibrosis (p <0.001). The rounded gross appearance of the kidneys, observed only in CTIN, was attributed to interstitial fibrosis, tubular atrophy, glomerular obsolescence and reduced thickness of the cortical layer laterally to the renal hilum, a region compatible with the renal poles. Cellular immunostaining for -smooth muscle actin (-SMA) was observed in all stages of CKD, demonstrating the role of myofibroblasts in the different processes and degrees of severity of CKD with the development of interstitial fibrosis. The second study aimed to determine the prevalence and clinical aspects of uremia in cats, in addition to the pathological aspects and the anatomical distribution of nonrenal uremic lesions. During the studied period (from January 2000 to October 2019), 1,330 cats were necropsied in LPV-UFSM, of which 78 had nonrenal uremic lesions (6%). In 75% of the cases, prolonged azotemia and uremia were the result of kidney disease. CKD in the form of NTIC was the most commonly observed renal process. The most frequente nonrenal uremic lesions observed in cats were pulmonary edema and hemorrhagic and/or ulcerative gastritis. Soft tissue mineralization and parathyroid hyperplasia were uncommon findings and fibrous osteodystrophy was not observed. The multisystemic presentation of nonrenal uremic lesions was observed only in 24% of the cases, and some uremic lesions usually observed in uremic dogs were not observed in the cats of this study.

Epidemiologia e distribuição de lesões extrarrenais de uremia em 161 cães / Epidemiology and distribution of extrarenal lesions of uremia in 161 dogs

Com o objetivo de determinar a epidemiologia e as características morfológicas, incluindo a localização anatômica, das lesões extrarrenais de uremia, bem como determinar as principais lesões do sistema urinário associadas à ocorrência de uremia, foram revisados os protocolos de necropsias de cães realizadas no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria de janeiro de 1996 a dezembro de 2012 (17 anos). Nesse período foram necropsiados 4.201 cães, sendo que 161 (3,8%) apresentaram lesões extrarrenais de uremia. Em 134 cães (83,2%) foram descritos sinais clínicos associados à uremia. As lesões extrarrenais mais frequentes, em ordem decrescente, foram: gastrite ulcerativa e hemorrágica (56,5%), mineralização de tecidos moles (55,9%), edema pulmonar (47,2%), estomatite e/ou glossite ulcerativa (30,4%), endocardite/trombose atrial e aórtica (28,6%), hiperplasia das paratireoides (9,3%), osteodistrofia fibrosa (8,1%), anemia (6,2%), laringite ulcerativa (5%), enterite ulcerativa/hemorrágica (3,7%), esofagite fibrinonecrótica (1,9%) e pericardite fibrinosa (1.9%). Na maioria dos casos as lesões extrarrenais de uremia foram decorrentes de azotemia prolongada por lesões renais graves, sendo as mais prevalentes a nefrite intersticial e a glomerulonefrite.(AU)

The aim of this study was to determine the epidemiology and the morphological characteristics (including the anatomic localization) of the extrarenal uremic lesions, as well as to describe the main lesions of the urinary system associated with the occurrence of uremia, through analysis of the protocols of necropsies performed in dogs from January 1996 to December 2012 (17 years) at the Laboratório de Patologia Veterinária of the Universidade Federal de Santa Maria. A total of 4,201 dogs were necropsied and 161 (3.8%) had extrarenal uremic lesions. In 134 dogs (83.2%) clinical signs associated with uremia were reported. The extrarenal lesions more often observed, in descending order of prevalence, were ulcerative and hemorrhagic gastritis (56.5%), soft-tissue mineralization (55.9%), pulmonary edema (47.2%), ulcerative stomatitis and/or glossitis (30.4%), endocarditis/atrial and aortic thrombosis (28.6%), parathyroid hyperplasia (9.3%), fibrous osteodystrophy (8.1%), anemia (6.2%), ulcerative laryngitis (5%), ulcerative and hemorrhagic enteritis (3.7%), fibrinonecrotic esophagitis (1.9%), and fibrinous pericarditis (1.9%). In most of the cases, the extrarenal lesions of uremia were due to prolonged azotemia secondary to severe renal lesions, such as interstitial nephritis and glomerulonephritis (the most prevalent ones).(AU)

Maxillofacial Fibrous Osteodystrophy in Equine: Case Report

A 14 year-old pregnant mare developed poor body condition (2/5) and diarrhea while grazing in kikuyu grass (Pennisetum clandestinum). Clinical findings included bulging of nasal and maxillary bones and mouth lacerations associated to spicules on the surface of molars and premolars. Teeth were easily fragmented and fell off. Necropsy findings included severe softening of the maxillary and mandibular bones. The mandible was easily breakable near to the masseter´s fossa. The parathyroid gland was increased in size. Histological findings were characterized by multiple irregular and very thin bone spicules in the bone tissue, most of them with microfractures, severe osteoclasts-mediated bone resorption and fibrous connective tissue proliferation. Hyperplasia and hypertrophy of parathyroid chief cells with cytoplasmic vacuolization were also observed. In conclusion, maxillofacial fibrous osteodystrophy caused by nutritional secondary hyperparathyroidism developed in a pregnant mare while grazing kikuyu grass for long periods of time without appropriate supplements. Kikuyu grass is characterized by high levels of oxalic acid that forms insoluble oxalates responsible for low calcium absorption in the small intestine and the progress of hyperparathyroidism.

Maxillofacial Fibrous Osteodystrophy in Equine: Case Report

A 14 year-old pregnant mare developed poor body condition (2/5) and diarrhea while grazing in kikuyu grass (Pennisetum clandestinum). Clinical findings included bulging of nasal and maxillary bones and mouth lacerations associated to spicules on the surface of molars and premolars. Teeth were easily fragmented and fell off. Necropsy findings included severe softening of the maxillary and mandibular bones. The mandible was easily breakable near to the masseter´s fossa. The parathyroid gland was increased in size. Histological findings were characterized by multiple irregular and very thin bone spicules in the bone tissue, most of them with microfractures, severe osteoclasts-mediated bone resorption and fibrous connective tissue proliferation. Hyperplasia and hypertrophy of parathyroid chief cells with cytoplasmic vacuolization were also observed. In conclusion, maxillofacial fibrous osteodystrophy caused by nutritional secondary hyperparathyroidism developed in a pregnant mare while grazing kikuyu grass for long periods of time without appropriate supplements. Kikuyu grass is characterized by high levels of oxalic acid that forms insoluble oxalates responsible for low calcium absorption in the small intestine and the progress of hyperparathyroidism.(AU)

DESENVOLVIMENTO DE FILHOTES DE GARÇA-VAQUEIRA (Bubulcus ibis - Linnaeus 1758) EM MINAS GERAIS: ASPECTOS MORFOLÓGICOS, ULTRASSONOGRÁFICOS E RADIOGRÁFICOS

A garça-vaqueira é uma espécie cosmopolita, no entanto ainda há lacunas na literatura sobre o desenvolvimento de seus filhotes e mesmo sobre parâmetros morfológicos em animais adultos.Sabe-se que a garça-vaqueira é uma espécie semi-altricial, dependendo dos pais nos seus primeiros 50 dias de vida. Os filhotes começam a andar pelos galhos com 14 dias e saem do ninho aos 30 dias. Durante este período ocorre seu desenvolvimento ósseo, com a ossificação de seus ossos longos. São escassos os estudos acerca do aparecimento de centros de ossificação pós eclosão em aves e do momento de fusão dos mesmos aos centros primários de ossificação. Foi realizado estudo com animais de uma colônia de pelecaniformes situada em Lavras Mg. Filhotes de garça-vaqueira que caiam dos ninhos eram recolhidos e radiografados, sendo parte dos animais utilizados para estudo através de coloração com azul de alciano, alizarina e diafanização para determinação de seus centros de ossificação com aparecimento pós-eclosão. Relacionou-se o momento de aparecimento dos centros de ossificação pós-eclosão e de fusão destes aos centros primários de ossos de membros pélvicos com o tipo de dependência paternas.A garça-vaqueira apresenta aparecimento e fusão dos centros de ossificação em idade precoce quando comparado a espécies precociais. Foi observado no ano de 2015 uma grande quantidade de filhotes caídos dos ninhos e demonstrando osteodistrofia fibrosa. Observou-se também filhotes com lesões corto-contusas sugerindo bicadas. Acredita-se que no ano estudado tenha ocorrido uma falta de alimento em quantidade suficiente e em adequada composição. Não houveram diferenças entre fatores climáticos no ano de 2016 e o ano de 2015, quando ocorreu a doença, dificultando o esclarecimento do fator causal. Foi realizado um terceiro estudo acerca dos parâmetros morfométricos oftálmicos dos filhotes de garças-vaqueiras. Observou-se que os parâmetros morfométricos à macroscopia e a ultrassonografia foram semelhantes aos de outras aves diurnas. A histologia dos olhos se demonstrou semelhante aos de outras espécies aviárias.

The cattle egret is a cosmopolitan species, however there are still gaps in the literature about the development of its young and even on morphological parameters in adult animals. It is known that the egret is a semi-altricial species, depending on the parents in the first 50 days of life. The chicks begin to walk the branches at 14 days and leave the nest at 30 days. During this period its bone development occurs, with the ossification of its long bones. Studies on the appearance of post-hatching ossification centers in birds and their fusion time to primary ossification centers are scarce. A study was conducted with animals of a pelecaniform colony located in Lavras - Mg. Cattle egrets that fell from their nests were collected and radiographed, being part of the animals used for study by staining with alcian blue, alizarin and diaphanization to determine their post-hatching ossification centers. The timing of the appearance of the post-hatching ossification centers and their fusion to the primary centers of pelvic limb bones was related to the type of paternal dependence. to precocial species. It was observed in 2015 a large number of chicks fallen from the nests and showing fibrous osteodystrophy. Puppies with cut-bruised lesions suggesting pecks were also observed. It is believed that in the year studied there was a lack of food in sufficient quantity and in adequate composition. There were no differences between climatic factors in 2016 and 2015, when the disease occurred, making it difficult to clarify the causal factor. A third study was performed on the ophthalmic morphometric parameters of the egret calves. The morphometric parameters at macroscopy and ultrasonography were similar to those of other diurnal birds. The histology of the eyes was similar to that of other avian species.

Fibrous Osteodystrophy in a Captive Common Eland Antelope (Taurotragus oryx)

Fibrous osteodystrophy (FO) is a common condition described mainly in domestic species, with only few cases described in wild ones kept in captivity. Herein we report a case of FO in a 2 yr-old female common eland antelope (Taurotragus oryx) maintained in captivity and fed with a horse pelleted ration plus hays. The animal showed a firm bilateral symmetrical enlargement of upper maxillary bones which was submitted to histological evaluation. Microscopic findings were those related to extensive bone resorption and fibroplasia.(AU)

OSTEODISTROFIA FIBROSA NUTRICIONAL EM JACARÉS DE CATIVEIRO NO ESTADO DA PARAÍBA

Os crocodilianos são subdivididos em três famílias: Alligatoridae, Crocodilidae e Gavialidae com total de 23 espécies. Quando jovens se alimentam de pequenos peixes e crustáceos, na fase adulta consomem vertebrados incluindo peixes, tartarugas, aves e mamíferos. As doenças ósseo-metabólicas envolvem um grupo de condições patológicas desenvolvidas como resultado de prolongadas deficiências em cálcio, fósforo e vitamina D. A Osteodistrofia fibrosa é a doença óssea metabólica mais comumente encontrada em répteis de cativeiro. A patogênese ocorre por estimulação das glândulas paratireoides devido à diminuição nas concentrações plasmáticas de cálcio, estimulando a secreção do paratormônio como mecanismo compensatório. Relatos de problemas no manejo nutricional são constantes, no entanto poucas informações estão disponíveis para essas espécies. No presente trabalho, o diagnóstico de osteodistrofia fibrosa em 17 jacarés, de três diferentes espécies, foi baseado nos aspectos epidemiológicos, histórico clínico, alterações radiográficas e achados macroscópicos e histopatológicos. As radiografias revelaram osteopenia, rarefação óssea, tortuosidade das vértebras e áreas de fraturas. Na necropsia foram observados graus variáveis de fragilidade óssea, deformações da coluna vertebral, alargamentos simétricos bilaterais dos ossos longos e paratireoides acentuadamente aumentadas. Os achados histopatológicos constituíram de marcada rarefação da matriz óssea, numerosas áreas císticas em meio o tecido ósseo, ilhas de cartilagem calcificadas e intensa substituição da matriz óssea por tecido conjuntivo fibroso. A ausência de lesões no parênquima renal e tumores paratireoidianos em todos os animais confirmam o diagnóstico definitivo de osteodistrofia fibrosa secundária ao hiperparatireoidismo nutricional. Após correção da alimentação com 0,1 ml de gluconato de cálcio para cada animal por via oral, nenhum caso adicional da doença foi observado.

Crocodilians are subdivided in three families: Alligatoridae, Crocodylidae and Gavialidae in a total of 23 species. When young they feed small fish and crustaceans, in adulthood consume vertebrates including fish, turtles, birds and mammals. Metabolic bone disease involves a group of pathological conditions developed as result of prolonged deficiencies in calcium, phosphorus and vitamin D. Fibrous osteodystrophy is a metabolic bone disease most commonly found in captive reptiles. The pathogenesis occurs by stimulation of the parathyroid glands due to decrease in plasma concentrations of calcium, stimulating the secretion of parathyroid hormone as a compensatory mechanism. Reports of problems on nutritional management are constant, however few information is available for these species. In this study, the diagnosis of fibrous osteodystrophy in 17 caimans from three different species was based on epidemiological aspects, clinical history, radiographic alterations, and mainly macroscopic and histopathological findings. Radiographs revealed osteopenia, bone thinning, tortuosity of the vertebrae and fractures areas. In the necropsy were observed variables degrees of bone fragility, spinal deformities, bilateral symmetrical enlargement of the long bones and parathyroid markedly increased. The histopathological findings consisted of marked rarefaction of bone matrix with severe thinning from maxillary and frontal bone forming numerous cystic areas with islands of cartilage calcified and intense replacement by fibrous tissue. The absence of injury at the renal parenchyma and parathyroid tumors in all animals confirm the diagnosis of fibrous osteodystrophy by nutritional secondary hyperparathyroidism. After feeding correction with 0.1 ml of calcium gluconate for each animal orally, no additional cases of disease was observed.

Osteodistrofia fibrosa nutricional em caprinos / Nutritional fibrous osteodystrophy in goats

Seven out of 25 goats from a southern Brazilian flock developed nutritional fibrous osteodystrophy. Affected animals were younger than 1 year of age and were confined in stalls and fed a concentrate ration containing 1:6 calcium:phosphorus ratio. The remaining flock (35 goats) was managed at pasture and showed no disease. Clinical signs were characterized by mandibular and maxillary enlargements, varying degrees of mouth opening and protruding tongue, dyspnea, apart of abnormalities of prehension and mastication. Affected animals had increased seric levels of phosphorus and parathormone, as well as higher alkaline phosphatase activity. Postmortem examination on three succumbed goats revealed bilateral enlargement of the maxilla and mandibula, and loose teeth, apart of multiple incomplete rib fractures in one of them. Severe diffuse proliferation of loose connective tissue surrounded the osteoid trabeculae, many of which were partially or completely non-mineralized. Mineralized osteoid trabeculae showed osteoclasts in the Howship's lacunae.(AU)

Sete de um total de 25 caprinos jovens (menos de um ano de idade) de um rebanho no sul do Brasil desenvolveram osteodistrofia fibrosa nutricional. Os animais afetados eram confinados em baias e alimentados com concentrado, cuja relação Ca:P era 1:6. O restante do rebanho (35 cabras) era mantido na pastagem e não desenvolveu a doença. Os sinais clínicos se caracterizaram por aumento de volume da mandibula e maxila, vários graus de abertura de boca com protrusão da língua, em associação com dispneia e anormalidades de apreensão de alimento e mastigação. Os animais afetados apresentaram os níveis séricos de fósforo e paratormônio aumentados, bem como maior atividade de fosfatase alcalina. Três caprinos foram necropsiados e os achados de necropsia incluíram aumento bilateral da maxi-la e mandíbula, dentes frouxos, além de múltiplas fraturas incompletas de costelas em um caprino. Microscopicamente, havia intensa proliferação de tecido conjuntivo frouxo ao redor de trabéculas ósseas, muitas das quais estavam parcial ou completamente não mineralizadas. Trabéculas ósseas mineralizadas apresentaram osteoclastos em lacunas de Howship.(AU)

Osteodistrofia fibrosa em equinos criados em pastagem de Panicum maximum cultivar Aruana: relato de casos / Fibrous osteodystrophy in horses raised on Aruana (Panicum maximum) pasture: case reports

Relata-se a ocorrência de osteodistrofia fibrosa em 38 equinos criados em pastagens de Panicum maximum cultivar Aruana, da raça Mangalarga Marchador, provenientes de uma propriedade localizada no estado do Paraná. No exame clínico geral, observou-se aumento bilateral e simétrico dos ossos da face e, também, aumento de volume na porção distal do rádio. A análise radiológica das áreas afetadas demonstrou redução da densidade óssea, e, na bioquímica sanguínea, 24 (63 por cento) animais apresentaram níveis de fósforo elevados. O exame bromatológico revelou níveis elevados de oxalato na pastagem de Aruana. Conclui-se que a ingestão de Aruana, forragem com altos níveis de oxalato, foi responsável pelo aparecimento de lesões de osteodistrofia fibrosa em equinos.(AU)

Fibrous osteodystrophy occurrence is reported in 38 Mangalarga Marchador horses raised on Aruana (Panicum maximum) pasture from a breeding farm in Paraná state. Clinical examination showed bilateral and symmetric increase in bones of face and an increase of volume at the radius distal portion. The radiologic analysis revealed bone density reduction in affected areas. Blood biochemist demonstrated high phosphorus levels in 24 animals (63 percent). Analysis of the pasture was performed and high levels of oxalate were found in the Aruana samples. It was concluded that the ingestion of Aruana, a pasture with high oxalate levels, was responsible for the appearing of fibrous osteodystrophy lesions in horses.(AU)

REPRODUÇÃO EXPERIMENTAL DE DOENÇA OSSEO METABOLICA EM JACARÉ DO PANTANAL (Caiman yacare): ASPECTOS CLÍNICOS E PATOLÓGICOS

A criação comercial de jacaré-do-pantanal (Caiman yacare) é uma atividade alternativa e legal dentro da Bacia do Rio Paraguai (pantanal matogrossense), que coíbe a caça predatória, preserva a espécie, tem reconhecido potencial econômico para o agronegócio e traz impacto social positivo para agricultura familiar. Em cativeiro, um dos principais problemas para a manutenção desta espécie, são as doenças nutricionais, associadas com dietas mal formuladas. As doenças ósseometabólicas (DOM) são frequentes em répteis cativos e comumente definidas como uma série de patologias que afetam a integridade e função óssea. Neste grupo é comum a osteodistrofia fibrosa (osteíte fibrosa cística), doença metabólica relativamente comum, caracterizada por extensa reabsorção óssea, acompanhada pela proliferação do tecido conjuntivo fibroso, e formação de cistos, com frequência, o osteoide aceleradamente formado não se torna mineralizado, formando osso imaturo. A partir da investigação epidemiológica que incluíram ocorrência de doenças, as dietas fornecidas e o manejo comumente adotado, uma DOM frequentemente relatada em criatórios de jacarés-do-pantanal foi reproduzida com o objetivo de caracterizar o quadro clínico e patológico. O estudo foi realizado no Laboratório de Patologia Veterinária, LPV-UFMT, filhotes de jacarés-do-pantanal, com idade aproximada de três meses, os quais foram pesados, medidos e divididos ao acaso em quatro grupos. Foram utilizadas duas dietas, uma balanceada e outra hiperfosfatêmica, cada uma associada à privação e exposição solar, ambas fornecidas cinco vezes por semana, durante seis meses. A evolução da doença foi acompanhada por avaliação clínica, radiográfica e biometria mensal para os parâmetros massa corpórea e comprimento rostro-cloacal, durante todo o período experimental. Ao término desse período, os jacarés foram eutanasiados e tiveram amostras coletadas, para estudos histológicos, através de colorações de eosina e hematoxilina e tricrômico de Masson. Os resultados obtidos, através da biometria mensal, mostraram que a dieta hiperfosfatêmica foi significativa para influenciar 8 negativamente o comprimento rostro-cloacal, ganho de peso e causou manifestação clínica da doença. Não ocorreu alterações significativas em relação a exposição ou privação a radiação solar. A DOM desenvolveu-se insidiosamente, tornando-se mais evidente entre o 3º e o 6º mês após o início do experimento. Os animais afetados mostraram dor quando manuseados, acentuada fraqueza muscular, perda de apetite, em alguns casos caquexia, dificuldade de locomoção e marcado amolecimento ósseo (consistência de borracha), especialmente da mandíbula e maxila e cifose principalmente torácica e lombar. Havia também aumento moderado de volume das paratireoides. O estudo radiográfico mostrou diminuição difusa na densidade do esqueleto, adelgaçamento cortical de ossos longos e deformidades angulares, particularmente da coluna vertebral. Microscopicamente notou-se hipertrofia de células da paratireoide caracterizada por aumento moderado do citoplasma, diminuição da eosinofilia e ocasionalmente vacuolização. Os ossos longos (fêmur e tíbia), chatos (do crânio e mandíbula) e vértebras, apresentavam marcada reabsorção óssea osteoclástica, com variável deposição de tecido conjuntivo fibroso e irregular aumento da atividade osteoblástica com formação de tecido ósseo imaturo. As alterações clínicas, que levaram a doença propriamente dita e a baixa taxa de crescimento atribuída à doença óssea metabólica, foram classificadas morfologicamente como osteodistrofia fibrosa, relacionada ao hiperparatireoidismo nutricional secundário.

The commercial breeding of the swamp alligator (Caiman yacare) is an legal and alternative activity in the region of the River Paraguai (Mato Grosso, Pantanal) that prohibits the illegal hunting, preserves the species and has recognized the economic potential for agribusiness and brings positive social impact to family farming. In captivity, a major problem for the maintenance of the species are the nutritional diseases associated with badly formulated diets. The bone-metabolic diseases (DOM) are common in captive reptiles and commonly defined as a range of disorders affecting bone integrity and function. This group is common to fibrous osteoarthritis (osteitis fibrosa cystica), a relatively common metabolic disorder characterized by extensive bone resorption, accompanied by proliferation of fibrous tissue and the formation of cysts, often the rapidly formed mineralized osteoid not become forming immature bone. From the epidemiological investigation that included the occurrence of diseases, provided diets and management commonly adopted, the DOM often reported in farms alligator-swampland was reproduced in order to characterize the clinical and pathological picture. The study was conducted at the Veterinary Pathology Laboratory, LPV-UFMT, young alligators from the marsh, aged approximately three months, which were weighed, measured and randomly divided into four groups. Two diets were used, and a balanced high phosphatemic another, each associated with withdrawal and exposure, both supplied five times a week for six months. The disease was accompanied by clinical, radiographic and biometrics monthly assessment for body mass parameters and snout-vent length, throughout the experimental period. At the end of that period, the alligators were euthanized and samples were collected for histological studies, through eosin staining and hematoxylin and Masson's trichrome. The results obtained from the monthly biometrics, showed that high phophatemic diet was significant for negative effect on the snout-vent length, weight gain and caused clinical manifestation of the disease. There was no significant changes in relation to exposure to solar radiation or deprivation. The DOM has developed insidiously, becoming more evident between the 3rd and the 6th month after the start of the experiment. Affected animals showed pain when handled, severe muscle weakness, loss of appetite, cachexia in some cases, difficulty of movement and marked bone softening (rubbery consistency), 10 particularly of mandible and maxilla and particularly the thoracic and lumbar kyphosis. There was also moderate enlargement of the parathyroid glands. Radiography showed diffuse decrease in skeletal density, cortical thinning and angular deformations of long bones, particularly the spine. Microscopically was noted parathyroid cells hypertrophy characterized by moderate increase in the cytoplasm, decreased eosinophilia and occasionally vacuolization. The long bones (femur and tibia), flat (skull and jaw) and vertebrae, had marked osteoclastic bone resorption, with variable deposition of fibrous connective tissue and irregular increase in osteoblastic activity with immature bone formation. The clinical, leading to disease itself and the low growth rate attributed to metabolic bone disease, were morphologically classified as fibrous osteodystrophy, related to secondary hyperparathyroidism nutrition.

Renal dysplasia in a Boxer dog: case report / Displasia renal em um cão Boxer: relato de caso

A 20-month-old female Boxer dog presented significant increase on the bilateral volume of the maxillaries. The necropsy revealed that the kidneys were reduced in size, pale, with lobular aspect, and reduced cortical-medullar ratio. The maxillaries cutting surface revealed trabecular aspect of brown-reddish color. In addition, the lesions observed by microscopy (asynchronic differentiation of nephrons, persistent mesenchyme, and atypical tubular epithelium) allowed establishing the diagnosis of renal dysplasia with secondary fibrous osteodystrophy.(AU)

Uma cadela Boxer com 20 meses de idade apresentou grande aumento de volume bilateral nos maxilares. À necropsia, os rins apresentavam-se diminuídos de tamanho, pálidos, com aspecto lobular e relação córtico-medular reduzida. A superfície de corte dos maxilares revelou aspecto trabecular de coloração marrom-avermelhada. As lesões observadas à microscopia (diferenciação assincrônica de néfrons, mesênquima persistente e proliferação tubular atípica) permitiram estabelecer o diagnóstico de displasia renal com osteodistrofia fibrosa secundária.(AU)

Minerais orgânicos na prevenção hiperparatireoidismo nutricional secundário em equinos / Prevention of secondary nutritional hyperparathyroidism in horses using organic minerals

Não é raro criar equinos em áreas onde baixo teor de fósforo, indisponibilidade de cálcio e teor de oxalato nas plantas podem levar a desequilíbrios resultando em hiperparatireoidismo nutricional secundário. Normalmente, os minerais atuam no organismo na forma orgânica e não inorgânica, porém, ainda há controvérsia na literatura quanto ao uso de minerais orgânicos. Objetivando-se avaliar o efeito da adição de ácido oxálico na dieta, causando desequilíbrio entre cálcio e fósforo em potros, e se dietas com minerais orgânicos, quando comparadas a dietas com minerais inorgânicos, seriam capazes de evitar esse desequilíbrio e evitar o desenvolvimento da patologia, analisaram-se: pesos dos animais, parâmetros sorológicos, concentrações minerais nos pêlos, densidade mineral óssea e biópsias ósseas. Utilizaram-se 24 potros, sem raça definida, com idade entre 18 e 24 meses. Cada tratamento foi composto por 6 potros (3 machos e 3 fêmeas), totalizando 4 tratamentos, em delineamento inteiramente casualizado, com medidas repetidas no tempo, em arranjo fatorial 2x2: suplementação com minerais orgânicos ou minerais inorgânicos, e presença ou ausência de oxalato na dieta. A colheita de amostras foi realizada em 150 dias, sendo a pesagem a cada 15 dias, os parâmetros sorológicos, mineralogramas capilares e densitometrias ósseas a cada 30 dias, e biópsias ósseas a cada 75 dias. Os resultados demonstraram aumento linear dos pesos em relação aos períodos, independente dos tratamentos e não foram observadas diferenças significativas nos hemogramas dos animais no período experimental. Houve diferença no paratormônio (PTH) plasmático entre o grupo tratado com minerais inorgânicos + oxalato em relação aos outros tratamentos. O hormônio calcitonina não diferiu entre tratamentos e durante períodos, assim como os minerais lítio, molibdênio, zinco, escândio, ouro, prata, tungstênio, zircônio, bário, berílio, cádmio, chumbo e mercúrio (dosados por mineralograma capilar). Foi observada diferença na concentração capilar de cálcio, enxofre, boro, cobre e estrôncio em relação aos períodos, independente dos tratamentos. As médias das concentrações capilares de manganês, no tratamento com minerais inorgânicos + oxalato não apresentaram diferenças entre períodos; porém nos outros tratamentos, assim como nos minerais fósforo, magnésio, potássio, silício, sódio, cobalto, cromo, ferro, selênio, titânio, alumínio e níquel houve efeito quadrático em relação aos períodos. Quanto à densidade mineral óssea do III metacarpiano, não foi observada diferença entre tratamentos, nem entre sexos. Foi observado efeito de período na mobilização de cálcio, fósforo e magnésio nos ossos, independente dos tratamentos. A partir dos resultados desse estudo, pode-se concluir que o modelo de indução de desequilíbrio entre cálcio e fósforo com inclusão de oxalato de potássio é efetivo e produz o resultado esperado. A suplementação mineral é capaz de aumentar a densidade mineral óssea, em potros, independente da fonte e do sexo. A criação de desequilíbrio mineral através da inclusão de oxalato de potássio diminui concentrações de cálcio, fósforo e magnésio nos ossos, independente da fonte suplementada. Potros suplementados com minerais orgânicos, mesmo quando desafiados com a inclusão de oxalato de potássio na dieta, mantém níveis de PTH plasmáticos estáveis, demonstrando melhor resistência ao desequilíbrio entre cálcio e fósforo e evitando o desenvolvimento da osteodistrofia fibrosa

Not uncommonly, the creation of horses in areas where the low phosphorus content, the unavailability of calcium and oxalate levels in plants can lead to imbalances resulting in nutritional secondary hyperparathyroidism. Minerals exert their functions in the body almost entirely as chelated minerals, and not as inorganic ion, however, there is still much controversy in the literature regarding the use of organic minerals. Aiming to evaluate whether the addition of oxalic acid in the diet could induce an imbalance between calcium and phosphorus in foals, and if the diet with organic minerals, compared with diet with inorganic minerals, would be able to avoid this imbalance and prevent the development of pathology, serological parameters, mineral concentrations in hair, bone mineral density and bone biopsies were analyzed. It was used 24 crossbred foals, aged between 18 and 24 months. Each treatment consisted of 6 foals (three males and three females), totaling four treatments in a completely randomized design with repeated measures on time, in a 2x2 factorial arrangement: supplementation with minerals organic or not (inorganic minerals), and presence or absence of oxalate in the diet. Sampling was conducted over a period of 150 days, and the animal were weighed every 15 days, the serological parameters, bone densitometry and hair analysis collected every 30 days, and bone biopsies every 75 days. The results showed a linear increase of the weights trough the periods, regardless of the treatments, and there were no significant differences in blood counts of animals in the experimental period. The values of parathyroid hormone (PTH) showed no difference between the group treated with inorganic minerals + oxalate in relation to other treatments, and in this treatment, the average was 5.75 times higher than the averages of other treatments. The results showed that the hormone calcitonin did not change between treatments and periods as well as the mineral lithium, molybdenum, zinc, scandium, gold, silver, tungsten, zirconium, barium, beryllium, cadmium, lead and mercury (measured by hair analysis). Difference was observed in hair concentration of calcium, sulfur, boron, copper and strontium during periods, regardless of treatments. The hairs average concentration of manganese in treatment with inorganic minerals + oxalate did not differ during periods, but the other treatments, as well as the minerals phosphorus, magnesium, potassium, silicon, sodium, cobalt, chromium, iron, selenium, titanium, aluminum and nickel showed quadratic effects for the periods. No difference was observed between treatments or between sexes on III metacarpal bone mineral density during the study period. A period effect was observed in the mobilization of calcium, phosphorus and magnesium in bone, independent of treatments. With the results of this study, we can conclude that the model of induced imbalance between calcium and phosphorus with addition of potassium oxalate is effective and produces the expected result. The mineral supplementation can increase bone mineral density in foals, regardless of source and sex. The creation of mineral imbalance by adding potassium oxalate decreases the concentration of calcium, phosphorus and magnesium in the bones of foals, regardless of source supplemented. Foals supplemented with organic minerals, even when challenged with the addition of potassium oxalate in the diet, maintains levels of plasma PTH stable, showing more resistance to the imbalance between calcium and phosphorus and avoiding the development of fibrous osteodystrophy