Resumo
A administração de fármacos para tratamento, prevenção e diagnóstico de doenças é amplamente utilizada na medicina veterinária; porém, esta prática pode provocar reações indesejadas em alguns casos, mesmo quando empregados nas doses, vias de administração e intervalos recomendados. Com relação às manifestações clínicas, essas podem envolver qualquer órgão ou sistema, mas a pele é o órgão mais frequentemente acometido, classificando-se então como uma farmacodermia. Uma farmacodermia, embora seja considerada uma afecção de rara ocorrência em cães, é extremamente importante na rotina veterinária, dada a sua gravidade e difícil diagnóstico decorrente da inespecificidade de sinais clínicos. O presente relato de caso teve como objetivo descrever o caso de uma cadela de onze anos de idade, da raça Yorkshire Terrier. O animal foi tratado com amoxicilina + clavulanato de potássio via subcutânea na dose de 20mg/mL, a cada 8 horas e metronidazol via intravenosa na dose de 15mg/mL, a cada 12 horas. Após o tratamento, este apresentou lesões cutâneas necróticas no dorso, demonstrando melhora clínica e regressão das lesões, após a suspensão imediata dos medicamentos. Assim, foi definido como diagnóstico presuntivo a farmacodermia do tipo necrólise epidermal tóxica. Desta forma, o presente trabalho visa difundir informações sobre a farmacodermia, buscando orientar na conduta terapêutica de pacientes com essa afecção, pelo fato de se tratar de uma doença pouco relatada na medicina veterinária.
The administration of drugs for the treatment, prevention, and diagnosis of diseases is widely used in veterinary medicine; however, this practice may cause unwanted reactions in some cases, even when used at the recommended doses, routes of administration, and intervals. Regarding the clinical manifestations, these can involve any organ or system, but the skin is the most frequently affected organ, classifying it as a pharmacoderma. Pharmacoderma, although considered a rare condition in dogs, is extremely important in the veterinary routine, given its severity and difficult diagnosis due to the non-specificity of clinical signs. The present case report aimed to describe the case of an eleven-year-old female Yorkshire Terrier. The animal was treated with amoxicillin + potassium clavulanate subcutaneously at a dose of 20mg/mL every 8 hours and intravenous metronidazole at a dose of 15mg/mL, every 12 hours. After the treatment, it presented necrotic skin lesions on the back, showing clinical improvement and regression of lesions after immediate suspension of medication. Thus, the pharmacoderma of toxic epidermal necrolysis type was defined as the presumptive diagnosis. In this way, Therefore, the present work aims to disseminate information about pharmacodermia, seeking to guide the therapeutic conduct of patients with this condition since it is a disease that is rarely reported in veterinary medicine.
Assuntos
Animais , Cães , Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Doenças do Cão , Metronidazol/efeitos adversos , Necrose/veterináriaResumo
As intoxicações por picadas de abelhas possuem grande relevância na medicina humana e veterinária. Os componentes da toxina apresentam ações lesivas aos tecidos, principalmente aos rins, e podem culminar com a morte, mesmo quando a dose inoculada é pequena. A identificação precoce desse tipo de intoxicação permite a implementação de medidas terapêuticas adequadas e a melhoria do prognóstico. Desta forma, o presente estudo foi desenvolvido com o objetivo de relatar os achados anatomopatológicos observados em dois cães, sem raça definida, os quais foram vítimas fatais de picadas de abelhas. Os animais eram irmãos de ninhada, um macho e uma fêmea, com três anos de idade e com cerca de 30kg. Os cães foram encontrados mortos no período da noite, já em rigor mortis, o que conduziu à suspeita de que a morte havia ocorrido há, no máximo, cinco horas. As principais lesões macroscópicas observadas foram: petéquias cutâneas, algumas associadas à presença de ferrões; congestão generalizada; hemorragia; necrose e edema; assim como insetos com morfologia compatível com Apis mellifera dispersos no trato gastrointestinal. Microscopicamente, degeneração, necrose e hemorragias renais constituíram os achados de maior importância, além de acentuado edema pulmonar, ao qual foi atribuída a causa mortis. Assim, as alterações mais importantes neste tipo de intoxicação são necrose, hemorragia, edema e congestão. Além disso, o óbito pode ocorrer de forma rápida, mesmo com baixas doses da toxina.
Bee sting poisonings have great relevance for both human and veterinary medicine. The toxin components present harmful actions on tissues, especially on kidneys, and can lead to death, even when the inoculated dose is small. The early identification of this type of intoxication allows the implementation of appropriate therapeutic measures and improvement of the prognosis. Thus, the present study aimed to report the anatomopathological findings of two mixed-breed dogs, which were fatal victims of bee stings. The animals were litter brothers, one male and one female, with three years old and weighing about 30kg. The dogs were found dead at night, already in rigor mortis, which led to the suspicion that the death had occurred no more than five hours ago. The main macroscopic lesions were: cutaneous petechiae, some of them associated with bee stingers, generalized congestion, haemorrhage, necrosis, and oedema, as well as insects with morphology compatible with Apis mellifera dispersed in the gastrointestinal tract. Microscopically, degeneration, necrosis, and renal haemorrhages were the most relevant findings, in addition to marked pulmonary oedema, which was considered the causa mortis. Thus, the most important alterations in this type of intoxication are necrosis, haemorrhage, oedema, and congestion. Moreover, death can occur quickly, even with low doses of the toxin.
Assuntos
Animais , Cães , Edema Pulmonar/etiologia , Venenos de Abelha/toxicidade , Abelhas , Mordeduras e Picadas de Insetos/veterinária , Necrose/veterináriaResumo
The downer cow syndrome (DCS) is characterized by an alert cow showing inability or reluctance to stand for 12 hours or more. This paper reported clinical, laboratory, and pathological findings in a Guzerá heifer with rhabdomyolysis, pigmenturia and acute renal failure following DCS. A 17-month-old Guzerá heifer was transported via a 350-km ride in a truck and showed sternal recumbency and severe difficulty in standing and walking. Neurological examination was unremarkable, and the heifer presented normal response to cranial nerves and spinal cord tests. Rectal palpation revealed a 5-month gravid uterus. No other abnormalities were noted in the pelvis or around the coxofemoral joints. Biochemical abnormalities included extremely high muscular enzyme activities (creatine phosphokinase and aspartate aminotransferase) and high creatinine levels. Urinalysis revealed blackish and cloudy urine, proteinuria, and a positive occult blood test. Spinal cord ultrasonography showed no abnormalities. This report highlighted an uncommon clinical presentation (myoglobinuria) and pathological findings in a heifer with DCS as a consequence of severe compressive muscle damage. Practitioners and producers must be aware of the risk of careless road transportation for long distances of cattle, especially obese cows, avoiding unnecessary suffering and expenses due to DCS.
A síndrome da vaca caída (SVC) é caracterizada por um bovino alerta que mostra incapacidade ou relutância em permanecer em estação por 12 horas ou mais. O objetivo deste trabalho é relatar os achados clínicos, laboratoriais e patológicos em uma novilha Guzerá com rabdomiólise, pigmentúria e insuficiência renal aguda após a SVC. Uma novilha da raça Guzerá, de 17 meses de idade, foi transportada de caminhão por 350 km e apresentou decúbito esternal, grande dificuldade para assumir estação e caminhar. O exame neurológico não demonstrou alterações, e a novilha possuía resposta normal aos testes de nervos cranianos e medula espinhal. A palpação retal revelou útero grávido de cinco meses. Nenhuma outra anormalidade foi observada na pelve ou na região das articulações coxofemorais. As anormalidades bioquímicas incluíram atividades de enzimas musculares (creatina fosfoquinase e aspartato aminotransferase) extremamente aumentadas e níveis elevados de creatinina. A urinálise revelou urina enegrecida e turva, proteinúria e teste de sangue oculto positivo. O exame ultrassonográfico da medula espinhal não apresentou anormalidades. Este relato evidencia uma apresentação clínica (mioglobinúria) e achados patológicos incomuns em uma novilha com SVC em consequência de extensa lesão muscular compressiva. Veterinários e produtores devem estar atentos aos riscos do transporte rodoviário descuidado por longas distâncias de bovinos, especialmente vacas obesas, evitando assim sofrimento e despesas desnecessárias decorrentes da SVC.
Assuntos
Animais , Feminino , Bovinos , Postura , Rabdomiólise/veterinária , Insuficiência Renal/veterinária , Mioglobinúria/veterinária , Obesidade/complicações , Obesidade/veterinária , Necrose/veterináriaResumo
A 14-month-old female Texel sheep that came from a herd made up of 19 animals showed haemoglobinuria, apathy, and anorexia, and died two days after the start of the clinical signals. The sheep remained in a natural grassland, where trailers were repaired, and multiple copper wires were deposited on the pasture. The animal had tachycardia, tachypnoea, pale mucous membranes, groaning pain on abdominal palpation, circling, head pressing, intensely hemolyzed plasma, and intense azotaemia. The necropsy showed focally extensive oedema in the inguinal and medial region of pelvic limbs, kidneys dark brown, and liver diffusely yellow with an evident moderate diffuse lobular pattern. The abomasum had a considerable amount of enameled material of thickness, firm to the cut, with 1-5 mm (copper wires). Histopathological examination showed marked diffuse tubular and glomerular coagulative necrosis in the kidneys, in addition to neutrophils, macrophages, lymphocytes, and plasma cells with moderate multifocal nephritis. The liver showed centrilobular necrosis, moderate hepatocellular edema, multifocal cholestasis, and in the lungs and brain mild to moderate diffuse edema. Copper content in the frozen liver (in natura) reached 1,598 mg/kg. Copper mesh ingestion led to sheep poisoning, which in this case was considered an atypical form of chronic primary copper poisoning.
Um ovino Texel de 14 meses de idade, que fazia parte de um rebanho de 19 animais, apresentou hemoglobinúria, apatia, anorexia e morreu dois dias após o início dos sinais clínicos. Os ovinos permaneciam em campo nativo, onde eram realizados consertos de trailers, e múltiplos fios de cobre ficavam depositados na pastagem. O animal apresentou taquicardia, taquipneia, mucosas pálidas, gemido de dor à palpação abdominal, além de andar em círculo, e pressão da cabeça contra obstáculos, plasma intensamente hemolisado e azotemia intensa. Na necropsia, havia edema na região inguinal e medial de membros pélvicos focalmente extenso, rins enegrecidos, e o fígado estava difusamente amarelado, com padrão lobular evidente difuso moderado. No abomaso, havia grande quantidade de material esmaltado, com 1-5mm de espessura, firme, que rangia ao ser cortado (fios de cobre). No exame histopatológico nos rins, havia necrose tubular e glomerular hemoglobinúrica difusa acentuada, além de nefrite de neutrófilios, macrófagos, linfócitos e plasmócitos multifocal moderada. No fígado, havia necrose centrolobular, tumefação hepatocelular e colestase multifocais moderadas; nos pulmões e no cérebro, edema difuso discreto a moderado. A dosagem de Cu no fígado revelou a presença de 1598mg/kg. A ingestão de malhas de cobre levou à intoxicação do ovino que, nesse caso, foi considerada uma forma atípica de intoxicação primária crônica por cobre.
Assuntos
Animais , Intoxicação , Ovinos , Cobre , Fígado , NecroseResumo
Background: Wounds that occur with tissue necrosis and that result from the application of medications through the most diverse accesses are described as drug skin medical embolism or Nicholas syndrome in human medicine, with wide description. In veterinary medicine, this subject has not yet been described extensively and specifically in veterinary medicine, especially regarding to wounds that occurred after the application of non-intravenous medications in horses, even though these lesions are recurrent in the clinical routine. This report aims to describe a case of skin necrosis in a horse, due to phenylbutazone infection. Case: A 7 year-old Mangalarga Marchador horse, weighing 400 kg, was admitted to the Veterinary Hospital for Large Animals of the Universiade Federal Rural do Rio de Janeiro (UFRRJ), with a history of phenylbutazone injection to the left side of the neck. The animal had an extensive wound on the neck and face on the left side and was characterized by the presence of cold and devitalized skin, with a hardened and parched appearance and that easily detached. During the anamnesis, a single administration of 10 mL of a non-steroidal anti-inflammatory drug based on phenylbutazone was reported intramuscularly for about 10 days to control the pain resulting from the claudication present for 14 days. The medication was administered in the region of the lateral border of the neck, on the left side. After drug administration, the animal presented an increase in volume at the application site. After 24 h, the lesion spread from the inoculation region, extending to the head and chest of the animal. During debridement, it was found that the lesion did not reach the underlying muscle tissue. In addition to the wound, the animal had upper eyelid palsy, lower lip, and auricular ptosis. Treatment with surgical debridement of devitalized tissue, topical application of ozonated sunflower oil, ketanserin, and a free skin graft was instituted. During hospitalization, the animal had a corneal ulcer in the left eye with an unfavorable prognosis due to paralysis of the upper eyelid, with enucleation of the affected eyeball. The animal was under veterinary care for 180 days and was discharged when his wound was already in an advanced stage of healing. Discussion: The history of the application of phenylbutazone intramuscularly and the location and characteristics of the lesion presented by the patient in the present report suggest that this animal presented aseptic tissue necrosis resulting from the administration of non-steroidal anti-inflammatory drugs, phenylbutazone. Although aseptic tissue necrosis, better known as Nicolau's syndrome or drug embolism cutis, is widely characterized and described in this species, there are studies in the literature that reproduce the syndrome in pigs and rabbits. Phenylbutazone was able to cause arterial damage, mainly in the tunica intima of the artery in which the medication was administered, with perivascular inflammatory infiltrate and subsequent skin necrosis at the site of administration. In addition to the skin lesion, the animal started to show signs compatible with the left facial nerve lesion, evidenced by the immobility of the upper eyelid and labial and ear ptosis. This resulted in corneal ulceration and subsequent enucleation. The animal also developed chewing difficulty in the first months of hospitalization. This dysfunction may be due to a lesion of the mandibular nerve, responsible for innervating the masticatory muscles and the oral mucosa. However, the animal showed improvement in this aspect, no longer showing this condition after 90 days of hospitalization. The treatment used was successful in healing the wound.
Assuntos
Animais , Fenilbutazona/efeitos adversos , Gangrena/veterinária , Cavalos/lesões , Síndrome de Nicolau/veterinária , Doença Iatrogênica/veterináriaResumo
Background: Low-intensity laser is effective in cellular metabolism, analgesia, and tissue repair. The bioelectric, bioenergetic, and biochemical effects of laser therapy stimulate local circulation, collagen formation, and epithelization. The objective of this study was to report the use of gallium-aluminum arsenide (GaAlAs) laser (830 nm) in healing two woundscaused by necrosis in a dog. Case: An 8-year-old bitch, a rescued victim of animal abuse, had tibiotarsal dislocation in the left posterior limb. Orthopedic surgery was performed with the placement of an external fixation device with six pins in the distal third of the left posterior limb. A radiographic examination performed 42 days after the surgery revealed the loss of the tibiotarsal ratio, decreased radiopacity of the carpal bones, edema, inflammation, muscle atrophy, and the rotation of the anatomical axis of the metatarsals and phalanges. It was then decided to perform a second orthopedic surgery, in which a bone graft and arthrodesis with an 8-screw titanium plate were performed. Four of the plate screws were placed proximally to the tibia and four distally to the tarsus in addition to a screw and a pin transfixed through the distal metaphyseal region of the tibia and calcaneus. Traction was felt during suturing in the dermis and epidermis of the limb, suggesting the possibility of dehiscence of the stitches. After 3 h of surgery, the limb was cold and edematous. After 5 days, the tissue of the medial region of the tarsus developed necrosis, exposing a wound 6 cm long, 1.5 cm wide, and 2 mm deep (wound 1). Another necrotic lesion was observed in the dorsal region of the tarsos - 6.5 cm long, 2 cm wide, 3 mm deep, and exposing 5 cm of the titanium plate (wound 2). Therapy with GaAlAs laser was then performed over the entire length of the wounds. In each therapeutic session, the laser was first used in punctual mode at 10 J/cm², 830 nm, 20 s at each point of the length of the lesion and then in scan mode at 10 J/cm², 830 nm, 1000 Hz, and 40 s continuously. Laser therapy sessions were conducted at 2-4 day intervals, with a 12-day interval between the eighth and ninth sessions. During the entire treatment, cleansing and debridement of the wounds were performed every 48 h with saline and chlorhexidine digluconate, using a compression bandage, as described earlier. Wound 1 healed completely after two laser therapy sessions. In wound 2, tissue repair stagnated after the ninth and last laser session, leaving 4 cm of the titanium plate still exposed. The limb could not support the body weight of the patient, and radiographic examination revealed that the anatomical axis of the metatarsals and the phalanges was rotated and bone conformation was poor. Given the anatomical conditions associated with the patient's clinical picture, it was decided to amputate the limb between the femur and tibia. Discussion: Therapeutic lasers act on mitochondrial respiration, increasing respiratory metabolism and stimulating DNA synthesis and tissue proliferation. In the present case, there was a decrease in inflammatory cells, edema, and the size of the wounds. The pathological conditions of the affected site, influence of trauma, and degree of tissue damage affected the results of the laser therapy. Despite the size difference between wounds 1 and 2, the exposed titanium plate was a determining factor for the partial healing of wound 2.
Assuntos
Animais , Feminino , Cães , Cicatrização/efeitos da radiação , Terapia com Luz de Baixa Intensidade/veterinária , Necrose/veterinária , Reabilitação/métodos , Terapia a Laser/veterinária , Lasers Semicondutores/uso terapêuticoResumo
In this study, the toxic effects of melittin on Madin-Darby Bovine Kidney cells (MDBK) were analyzed with respect to mitochondrial functionality by reduction of MTT and flow cytometry, apoptosis potential, necrosis, oxygen reactive species (ROS) production, lipid peroxidation, and DNA fragmentation using flow cytometry and cell membrane destabilization by confocal microscopy. The toxicity presented dose-dependent characteristics and mitochondrial activity was inhibited by up to 78.24 ±3.59% (P<0.01, n = 6) in MDBK cells exposed to melittin (10µg/mL). Flow cytometry analysis revealed that melittin at 2µg/mL had the highest necrosis rate (P<0.05) for the cells. The lipoperoxidation of the membranes was also higher at 2µg/mL of melittin (P<0.05), which was further confirmed by the microphotographs obtained by confocal microscopy. The highest ROS production occurred when the cells were exposed to 2.5µg/mL melittin (P<0.05), and this concentration also increased DNA fragmentation (P<0.05). There was a significative and positive correlation between the lipoperoxidation of membranes with ROS (R=0.4158), mitochondrial functionality (R=0.4149), and apoptosis (R=0.4978). Thus, the oxidative stress generated by melittin culminates in the elevation of intracellular ROS that initiates a cascade of toxic events in MDBK cells.(AU)
Neste estudo, os efeitos tóxicos da melitina em células Madin-Darby Bovine Kidney (MDBK) foram analisados quanto à funcionalidade mitocondrial, por redução de MTT e citometria de fluxo, potencial de apoptose, necrose, produção de espécies reativas de oxigênio (ROS), peroxidação lipídica e fragmentação de DNA, utilizando-se citometria de fluxo e desestabilização da membrana celular, por microscopia confocal. A toxicidade apresentou características dose-dependentes e a atividade mitocondrial foi inibida até 78,24±3,59% (P<0,01, n = 6) em células MDBK expostas à melitina (10µg/mL). Análises por citometria de fluxo revelaram que a melitina a 2µg/mL apresentou o maior índice necrótico celular (P<0,05). A maior lipoperoxidação de membranas também foi na concentração de 2µg/mL de melitina (P<0,05), o que foi posteriormente confirmado por microscopia confocal. A maior produção de ROS aconteceu quando as células foram expostas a 2,5µg/mL de melitina (P<0,05), e essa concentração também aumentou a fragmentação de DNA (P<0,05). Houve uma significativa correlação positiva entre a lipoperoxidação de membranas e a produção de ROS (R=0,4158), funcionalidade mitocondrial (R=0,4149) e apoptose (R=0,4978). Portanto, o estresse oxidativo gerado pela melitina culminou na elevação de ROS intracelular, que inicia uma cascata de eventos tóxicos nas células MDBK.(AU)
Assuntos
Espécies Reativas de Oxigênio/efeitos adversos , Apoptose , Citotoxinas/análise , Meliteno/análise , Venenos de Abelha/análise , Microscopia Confocal , Citometria de FluxoResumo
ABSTRACT: This study describes an outbreak of acute necrotic hepatopathy associated with spontaneous poisoning by Lantana camara L. in dairy cattle. A herd of 15 cows and heifers was introduced into a native pasture with limited food supply, and, sixteen days later, eight animals had spontaneous nasal hemorrhage, fever, lethargy, jaundice, and dry, dark stools with mucus and blood. The clinical course varied from two to five days. In the pasture where the cattle were kept, abundant adult specimens of L. camara L. with evident signs of consumption were observed. In total, seven cattle died and necropsy was performed in three of them. All animals had moderate jaundice, hemorrhage in the subcutaneous tissue and on the surface of different organs. The liver was slightly enlarged, with orange discoloration and enhanced lobular pattern. Histologically, multifocal areas of coagulative necrosis of hepatocytes in the centrilobular area, occasionally extending to the midzonal area, were observed, as well as marked hepatocellular degeneration and prominent cholestasis. The current study suggests that L. camara L. poisoning should be considered a differential diagnosis of acute and necrotic hepatotoxicity in cattle, despite the absence of photosensitization.
RESUMO: Esse estudo descreve um surto de hepatopatia necrótica aguda associada a intoxicação espontânea por Lantana camara L. em bovinos leiteiros. Um lote de 15 vacas e novilhas foram introduzidas em um piquete com campo nativo, com escassa oferta de alimento. Após dezesseis dias, oito animais manifestaram epistaxe, febre, apatia, icterícia, fezes ressecadas e escuras com muco e sangue. A evolução do quadro clínico variou de dois a cinco dias. No piquete em que os bovinos estavam alojados havia grande quantidade de L. camara L. com sinais evidentes de consumo. No total, sete bovinos morreram, e destes, o exame post mortem foi realizado em três. Os bovinos exibiam moderada icterícia, hemorragias no tecido subcutâneo e na superfície de diferentes órgãos. O fígado estava discretamente aumentado, com coloração alaranjada e padrão lobular evidente. As lesões histológicas consistiam em acentuada necrose de coagulação de hepatócitos em região centrolobular, por vezes se estendendo a região mediozonal, além de acentuada degeneração dos hepatócitos e evidente Colestase. O presente trabalho alerta para que intoxicação por L. camara L. seja levada em consideração nos diagnósticos diferenciais de hepatotoxicidade necrótica aguda em bovinos, mesmo sem indícios de fotossensibilização.
Resumo
ABSTRACT: This study describes the epidemiological, clinical, and pathological aspects of spontaneous and experimental poisoning by nitroxinil at 34% concentration in goats. The outbreak occurred on a farm in the municipality of Prata, Paraíba state. Nitroxinil was administered to a herd of 120 goats, of which 18 presented with anorexia, vocalization, abdominal distension, weakness, staggering, and falls. Necropsy of three goats revealed that the main lesion was acute liver injury. Histologically the liver showed centrilobular necrosis associated with hemorrhage and hepatocyte degeneration. In the kidneys, tubular nephrosis with granular cylinder formations was observed. The lungs showed multifocal to coalescent areas of moderate interalveolar edema and vascular congestion. Experimental poisoning was carried out in two goats, with the same medication and doses administered on the farm. The experimental goats showed clinical signs and macroscopic and histological changes similar to the spontaneously poisoned goats. The diagnosis of nitroxinil poisoning was made based on epidemiological, clinical, and pathological data, and confirmed by experimental poisoning. The administration of nitroxinil in high doses, associated with high ambient temperature and physical exercises, can cause poisoning with high lethality in goats.
RESUMO: Este estudo descreve os aspectos epidemiológicos, clínicos e patológicos da intoxicação espontânea e experimental por nitroxinil na concentração de 34% em caprinos. O surto ocorreu em uma fazenda no município de Prata, Paraíba. Nitroxinil foi administrado a um rebanho de 120 cabras, das quais 18 apresentavam anorexia, vocalização, distensão abdominal, fraqueza, cambaleando e quedas. A necropsia de três cabras revelou que a lesão principal era uma lesão hepática aguda. Histologicamente, o fígado apresentava necrose centrolobular associada a hemorragia e degeneração de hepatócitos. Nos rins, nefrose tubular com formações de cilindro granular foi observada. Os pulmões apresentavam áreas multifocais a coalescentes de edema interalveolar moderado e congestão vascular. A intoxicação experimental foi realizada em duas cabras, com a mesma medicação e doses administradas na fazenda. As cabras experimentais apresentaram sinais clínicos e alterações macroscópicas e histológicas semelhantes às cabras intoxicadas espontaneamente. O diagnóstico de intoxicação por nitroxinil foi feito com base em dados epidemiológicos, clínicos e patológicos, e confirmado por intoxicação experimental. A administração de nitroxinil em altas doses, associada à alta temperatura ambiente e exercícios físicos, pode causar intoxicação com alta letalidade em caprinos.
Resumo
This study describes an outbreak of acute necrotic hepatopathy associated with spontaneous poisoning by Lantana camara L. in dairy cattle. A herd of 15 cows and heifers was introduced into a native pasture with limited food supply, and, sixteen days later, eight animals had spontaneous nasal hemorrhage, fever, lethargy, jaundice, and dry, dark stools with mucus and blood. The clinical course varied from two to five days. In the pasture where the cattle were kept, abundant adult specimens of L. camara L. with evident signs of consumption were observed. In total, seven cattle died and necropsy was performed in three of them. All animals had moderate jaundice, hemorrhage in the subcutaneous tissue and on the surface of different organs. The liver was slightly enlarged, with orange discoloration and enhanced lobular pattern. Histologically, multifocal areas of coagulative necrosis of hepatocytes in the centrilobular area, occasionally extending to the midzonal area, were observed, as well as marked hepatocellular degeneration and prominent cholestasis. The current study suggests that L. camara L. poisoning should be considered a differential diagnosis of acute and necrotic hepatotoxicity in cattle, despite the absence of photosensitization.(AU)
Esse estudo descreve um surto de hepatopatia necrótica aguda associada a intoxicação espontânea por Lantana camara L. em bovinos leiteiros. Um lote de 15 vacas e novilhas foram introduzidas em um piquete com campo nativo, com escassa oferta de alimento. Após dezesseis dias, oito animais manifestaram epistaxe, febre, apatia, icterícia, fezes ressecadas e escuras com muco e sangue. A evolução do quadro clínico variou de dois a cinco dias. No piquete em que os bovinos estavam alojados havia grande quantidade de L. camara L. com sinais evidentes de consumo. No total, sete bovinos morreram, e destes, o exame post mortem foi realizado em três. Os bovinos exibiam moderada icterícia, hemorragias no tecido subcutâneo e na superfície de diferentes órgãos. O fígado estava discretamente aumentado, com coloração alaranjada e padrão lobular evidente. As lesões histológicas consistiam em acentuada necrose de coagulação de hepatócitos em região centrolobular, por vezes se estendendo a região mediozonal, além de acentuada degeneração dos hepatócitos e evidente Colestase. O presente trabalho alerta para que intoxicação por L. camara L. seja levada em consideração nos diagnósticos diferenciais de hepatotoxicidade necrótica aguda em bovinos, mesmo sem indícios de fotossensibilização.(AU)
Assuntos
Animais , Feminino , Bovinos , Bovinos , Lantana/toxicidade , Ingestão de Alimentos , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Hepatopatias , Plantas TóxicasResumo
This study describes the epidemiological, clinical, and pathological aspects of spontaneous and experimental poisoning by nitroxinil at 34% concentration in goats. The outbreak occurred on a farm in the municipality of Prata, Paraíba state. Nitroxinil was administered to a herd of 120 goats, of which 18 presented with anorexia, vocalization, abdominal distension, weakness, staggering, and falls. Necropsy of three goats revealed that the main lesion was acute liver injury. Histologically the liver showed centrilobular necrosis associated with hemorrhage and hepatocyte degeneration. In the kidneys, tubular nephrosis with granular cylinder formations was observed. The lungs showed multifocal to coalescent areas of moderate interalveolar edema and vascular congestion. Experimental poisoning was carried out in two goats, with the same medication and doses administered on the farm. The experimental goats showed clinical signs and macroscopic and histological changes similar to the spontaneously poisoned goats. The diagnosis of nitroxinil poisoning was made based on epidemiological, clinical, and pathological data, and confirmed by experimental poisoning. The administration of nitroxinil in high doses, associated with high ambient temperature and physical exercises, can cause poisoning with high lethality in goats.(AU)
Este estudo descreve os aspectos epidemiológicos, clínicos e patológicos da intoxicação espontânea e experimental por nitroxinil na concentração de 34% em caprinos. O surto ocorreu em uma fazenda no município de Prata, Paraíba. Nitroxinil foi administrado a um rebanho de 120 cabras, das quais 18 apresentavam anorexia, vocalização, distensão abdominal, fraqueza, cambaleando e quedas. A necropsia de três cabras revelou que a lesão principal era uma lesão hepática aguda. Histologicamente, o fígado apresentava necrose centrolobular associada a hemorragia e degeneração de hepatócitos. Nos rins, nefrose tubular com formações de cilindro granular foi observada. Os pulmões apresentavam áreas multifocais a coalescentes de edema interalveolar moderado e congestão vascular. A intoxicação experimental foi realizada em duas cabras, com a mesma medicação e doses administradas na fazenda. As cabras experimentais apresentaram sinais clínicos e alterações macroscópicas e histológicas semelhantes às cabras intoxicadas espontaneamente. O diagnóstico de intoxicação por nitroxinil foi feito com base em dados epidemiológicos, clínicos e patológicos, e confirmado por intoxicação experimental. A administração de nitroxinil em altas doses, associada à alta temperatura ambiente e exercícios físicos, pode causar intoxicação com alta letalidade em caprinos.(AU)
Assuntos
Animais , Intoxicação , Cabras , Hepatócitos , Rim , Anti-Helmínticos , Necrose , NitroxinilaResumo
This study describes the epidemiological, clinical, and pathological aspects of spontaneous and experimental poisoning by nitroxinil at 34% concentration in goats. The outbreak occurred on a farm in the municipality of Prata, Paraíba state. Nitroxinil was administered to a herd of 120 goats, of which 18 presented with anorexia, vocalization, abdominal distension, weakness, staggering, and falls. Necropsy of three goats revealed that the main lesion was acute liver injury. Histologically the liver showed centrilobular necrosis associated with hemorrhage and hepatocyte degeneration. In the kidneys, tubular nephrosis with granular cylinder formations was observed. The lungs showed multifocal to coalescent areas of moderate interalveolar edema and vascular congestion. Experimental poisoning was carried out in two goats, with the same medication and doses administered on the farm. The experimental goats showed clinical signs and macroscopic and histological changes similar to the spontaneously poisoned goats. The diagnosis of nitroxinil poisoning was made based on epidemiological, clinical, and pathological data, and confirmed by experimental poisoning. The administration of nitroxinil in high doses, associated with high ambient temperature and physical exercises, can cause poisoning with high lethality in goats.(AU)
Este estudo descreve os aspectos epidemiológicos, clínicos e patológicos da intoxicação espontânea e experimental por nitroxinil na concentração de 34% em caprinos. O surto ocorreu em uma fazenda no município de Prata, Paraíba. Nitroxinil foi administrado a um rebanho de 120 cabras, das quais 18 apresentavam anorexia, vocalização, distensão abdominal, fraqueza, cambaleando e quedas. A necropsia de três cabras revelou que a lesão principal era uma lesão hepática aguda. Histologicamente, o fígado apresentava necrose centrolobular associada a hemorragia e degeneração de hepatócitos. Nos rins, nefrose tubular com formações de cilindro granular foi observada. Os pulmões apresentavam áreas multifocais a coalescentes de edema interalveolar moderado e congestão vascular. A intoxicação experimental foi realizada em duas cabras, com a mesma medicação e doses administradas na fazenda. As cabras experimentais apresentaram sinais clínicos e alterações macroscópicas e histológicas semelhantes às cabras intoxicadas espontaneamente. O diagnóstico de intoxicação por nitroxinil foi feito com base em dados epidemiológicos, clínicos e patológicos, e confirmado por intoxicação experimental. A administração de nitroxinil em altas doses, associada à alta temperatura ambiente e exercícios físicos, pode causar intoxicação com alta letalidade em caprinos.(AU)
Assuntos
Animais , Intoxicação , Cabras , Hepatócitos , Rim , Anti-Helmínticos , Necrose , NitroxinilaResumo
This study describes an outbreak of acute necrotic hepatopathy associated with spontaneous poisoning by Lantana camara L. in dairy cattle. A herd of 15 cows and heifers was introduced into a native pasture with limited food supply, and, sixteen days later, eight animals had spontaneous nasal hemorrhage, fever, lethargy, jaundice, and dry, dark stools with mucus and blood. The clinical course varied from two to five days. In the pasture where the cattle were kept, abundant adult specimens of L. camara L. with evident signs of consumption were observed. In total, seven cattle died and necropsy was performed in three of them. All animals had moderate jaundice, hemorrhage in the subcutaneous tissue and on the surface of different organs. The liver was slightly enlarged, with orange discoloration and enhanced lobular pattern. Histologically, multifocal areas of coagulative necrosis of hepatocytes in the centrilobular area, occasionally extending to the midzonal area, were observed, as well as marked hepatocellular degeneration and prominent cholestasis. The current study suggests that L. camara L. poisoning should be considered a differential diagnosis of acute and necrotic hepatotoxicity in cattle, despite the absence of photosensitization.(AU)
Esse estudo descreve um surto de hepatopatia necrótica aguda associada a intoxicação espontânea por Lantana camara L. em bovinos leiteiros. Um lote de 15 vacas e novilhas foram introduzidas em um piquete com campo nativo, com escassa oferta de alimento. Após dezesseis dias, oito animais manifestaram epistaxe, febre, apatia, icterícia, fezes ressecadas e escuras com muco e sangue. A evolução do quadro clínico variou de dois a cinco dias. No piquete em que os bovinos estavam alojados havia grande quantidade de L. camara L. com sinais evidentes de consumo. No total, sete bovinos morreram, e destes, o exame post mortem foi realizado em três. Os bovinos exibiam moderada icterícia, hemorragias no tecido subcutâneo e na superfície de diferentes órgãos. O fígado estava discretamente aumentado, com coloração alaranjada e padrão lobular evidente. As lesões histológicas consistiam em acentuada necrose de coagulação de hepatócitos em região centrolobular, por vezes se estendendo a região mediozonal, além de acentuada degeneração dos hepatócitos e evidente Colestase. O presente trabalho alerta para que intoxicação por L. camara L. seja levada em consideração nos diagnósticos diferenciais de hepatotoxicidade necrótica aguda em bovinos, mesmo sem indícios de fotossensibilização.(AU)
Assuntos
Animais , Feminino , Bovinos , Bovinos , Lantana/toxicidade , Ingestão de Alimentos , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Hepatopatias , Plantas TóxicasResumo
ABSTRACT: In this study, an outbreak of spontaneous poisoning by Dodonaea viscosa (D. viscosa) in a herd of dairy cattle in the municipality of Capão do Leão, Rio Grande do Sul, was investigated. Three deaths occurred in a batch of 16 Jersey cattle, aged between three and four years, kept in a native field. The clinical signs observed were apathy, decreased production, and anorexia, with death occurring within approximately 48 h after the onset of signs. The three cattle were necropsied, and tissue samples were sent for histopathological examination. Necropsy findings included serosanguineous fluid in the abdominal cavity, intestines with congested serosa, and marked mesenteric edema. The mucosa of the abomasum of two of the animals was hemorrhagic with bloody content, and among the ruminal content of a bovine, leaves with morphological characteristics compatible with D. viscosa were observed. The livers of the three animals were enlarged, with accentuation of the lobular pattern. Histologically, centrilobular coagulation necrosis with congestion and hemorrhage was observed in the liver. Vacuolization and degeneration of hepatocytes were observed in the mid-zonal and periportal regions. The diagnosis of poisoning by D. viscosa leaves was based on epidemiological data, necropsy findings, and histopathological alterations. The presence of the plant in the rumen and in the grazing site of the affected cattle was essential for the diagnosis.
RESUMO: Neste trabalho, é descrito um surto de intoxicação espontânea por Dodonaea viscosa (D. viscosa) ocorrido em um rebanho de bovinos leiteiros, no município de Capão do Leão, no Rio Grande do Sul. Ocorreram três mortes em um lote de 16 bovinos da raça Jersey com idades entre três e quatro anos, mantidos em campo nativo. Os sinais clínicos observados foram apatia, queda na produção e anorexia, com morte em aproximadamente 48 horas após o início dos sinais. Os três bovinos foram necropsiados, e amostras de tecidos foram encaminhadas para exame histopatológico. Os achados de necropsia incluíam líquido serossanguinolento na cavidade abdominal, intestinos com serosas congestas e marcado edema de mesentério. A mucosa do abomaso de dois animais apresentava-se hemorrágica com conteúdo sanguinolento e, em meio ao conteúdo ruminal de um bovino foram observadas folhas com caracteres morfológicos compatíveis com D. viscosa. O fígado dos três animais estava aumentado, com acentuação do padrão lobular. Histologicamente no fígado havia necrose de coagulação centrolobular com congestão e hemorragia. Nas regiões médio-zonal e periportal observou-se vacuolização e degeneração dos hepatócitos. O diagnóstico de intoxicação pelas folhas D. viscosa foi baseado nos dados epidemiológicos, nos achados de necropsia e nas alterações histopatológicas. A presença da planta no rúmen e no local de pastoreio dos bovinos afetados foi fundamental para o diagnóstico.
Resumo
In this study, an outbreak of spontaneous poisoning by Dodonaea viscosa (D. viscosa) in a herd of dairy cattle in the municipality of Capão do Leão, Rio Grande do Sul, was investigated. Three deaths occurred in a batch of 16 Jersey cattle, aged between three and four years, kept in a native field. The clinical signs observed were apathy, decreased production, and anorexia, with death occurring within approximately 48 h after the onset of signs. The three cattle were necropsied, and tissue samples were sent for histopathological examination. Necropsy findings included serosanguineous fluid in the abdominal cavity, intestines with congested serosa, and marked mesenteric edema. The mucosa of the abomasum of two of the animals was hemorrhagic with bloody content, and among the ruminal content of a bovine, leaves with morphological characteristics compatible with D. viscosa were observed. The livers of the three animals were enlarged, with accentuation of the lobular pattern. Histologically, centrilobular coagulation necrosis with congestion and hemorrhage was observed in the liver. Vacuolization and degeneration of hepatocytes were observed in the mid-zonal and periportal regions. The diagnosis of poisoning by D. viscosa leaves was based on epidemiological data, necropsy findings, and histopathological alterations. The presence of the plant in the rumen and in the grazing site of the affected cattle was essential for the diagnosis.(AU)
Neste trabalho, é descrito um surto de intoxicação espontânea por Dodonaea viscosa (D. viscosa) ocorrido em um rebanho de bovinos leiteiros, no município de Capão do Leão, no Rio Grande do Sul. Ocorreram três mortes em um lote de 16 bovinos da raça Jersey com idades entre três e quatro anos, mantidos em campo nativo. Os sinais clínicos observados foram apatia, queda na produção e anorexia, com morte em aproximadamente 48 horas após o início dos sinais. Os três bovinos foram necropsiados, e amostras de tecidos foram encaminhadas para exame histopatológico. Os achados de necropsia incluíam líquido serossanguinolento na cavidade abdominal, intestinos com serosas congestas e marcado edema de mesentério. A mucosa do abomaso de dois animais apresentava-se hemorrágica com conteúdo sanguinolento e, em meio ao conteúdo ruminal de um bovino foram observadas folhas com caracteres morfológicos compatíveis com D. viscosa. O fígado dos três animais estava aumentado, com acentuação do padrão lobular. Histologicamente no fígado havia necrose de coagulação centrolobular com congestão e hemorragia. Nas regiões médio-zonal e periportal observou-se vacuolização e degeneração dos hepatócitos. O diagnóstico de intoxicação pelas folhas D. viscosa foi baseado nos dados epidemiológicos, nos achados de necropsia e nas alterações histopatológicas. A presença da planta no rúmen e no local de pastoreio dos bovinos afetados foi fundamental para o diagnóstico.(AU)
Assuntos
Animais , Bovinos , Intoxicação , Coagulação Sanguínea , Hepatócitos , Sapindaceae , Fluconazol , NecroseResumo
In this study, an outbreak of spontaneous poisoning by Dodonaea viscosa (D. viscosa) in a herd of dairy cattle in the municipality of Capão do Leão, Rio Grande do Sul, was investigated. Three deaths occurred in a batch of 16 Jersey cattle, aged between three and four years, kept in a native field. The clinical signs observed were apathy, decreased production, and anorexia, with death occurring within approximately 48 h after the onset of signs. The three cattle were necropsied, and tissue samples were sent for histopathological examination. Necropsy findings included serosanguineous fluid in the abdominal cavity, intestines with congested serosa, and marked mesenteric edema. The mucosa of the abomasum of two of the animals was hemorrhagic with bloody content, and among the ruminal content of a bovine, leaves with morphological characteristics compatible with D. viscosa were observed. The livers of the three animals were enlarged, with accentuation of the lobular pattern. Histologically, centrilobular coagulation necrosis with congestion and hemorrhage was observed in the liver. Vacuolization and degeneration of hepatocytes were observed in the mid-zonal and periportal regions. The diagnosis of poisoning by D. viscosa leaves was based on epidemiological data, necropsy findings, and histopathological alterations. The presence of the plant in the rumen and in the grazing site of the affected cattle was essential for the diagnosis.(AU)
Neste trabalho, é descrito um surto de intoxicação espontânea por Dodonaea viscosa (D. viscosa) ocorrido em um rebanho de bovinos leiteiros, no município de Capão do Leão, no Rio Grande do Sul. Ocorreram três mortes em um lote de 16 bovinos da raça Jersey com idades entre três e quatro anos, mantidos em campo nativo. Os sinais clínicos observados foram apatia, queda na produção e anorexia, com morte em aproximadamente 48 horas após o início dos sinais. Os três bovinos foram necropsiados, e amostras de tecidos foram encaminhadas para exame histopatológico. Os achados de necropsia incluíam líquido serossanguinolento na cavidade abdominal, intestinos com serosas congestas e marcado edema de mesentério. A mucosa do abomaso de dois animais apresentava-se hemorrágica com conteúdo sanguinolento e, em meio ao conteúdo ruminal de um bovino foram observadas folhas com caracteres morfológicos compatíveis com D. viscosa. O fígado dos três animais estava aumentado, com acentuação do padrão lobular. Histologicamente no fígado havia necrose de coagulação centrolobular com congestão e hemorragia. Nas regiões médio-zonal e periportal observou-se vacuolização e degeneração dos hepatócitos. O diagnóstico de intoxicação pelas folhas D. viscosa foi baseado nos dados epidemiológicos, nos achados de necropsia e nas alterações histopatológicas. A presença da planta no rúmen e no local de pastoreio dos bovinos afetados foi fundamental para o diagnóstico.(AU)
Assuntos
Animais , Bovinos , Intoxicação , Coagulação Sanguínea , Hepatócitos , Sapindaceae , Fluconazol , NecroseResumo
Iatrogenic intoxications occur in domestic animals. Mortality was observed in a group of calves, reaching 20 deaths until the day of the technical visit, with or without sudden clinical signs, on a farm in the city of Pires do Rio, State of Goiás, Brazil. Deaths after the visit were not accounted systematically. Clinical signs included muscle weakness, ataxia, recumbency, bilateral jugular distention, and death. Suspected diagnosis of poisoning by ionophore antibiotics was made based on clinical and laboratory findings from nine animals, which included high plasma CK and LDH levels, as well as on anatomopathological findings of a recently dead calf, which showed myocardial and skeletal muscle degeneration and necrosis. Monensin overdose (25.5 µg/kg in skeletal muscle and 209.4 µg/kg in the liver) was detected by liquid-chromatography and mass-spectrophotometry analysis, contributing to the confirmation of ionophore poisoning diagnosis.(AU)
Intoxicações iatrogênicas ocorrem em animais domésticos. Um lote de bezerros apresentou mortalidade, chegando a 20 mortes até o dia da visita técnica, após sinais clínicos súbitos ou ausência destes, em uma propriedade rural do município de Pires do Rio, estado de Goiás, Brasil. As mortes após a visita não foram sistematicamente contabilizadas. Os sinais incluíam fraqueza muscular, ataxia, decúbito, distensão bilateral da veia jugular e morte. Baseado nos achados clínicos e laboratoriais de nove bovinos, que incluíram níveis de CK e LDH elevados no plasma, assim como degeneração e necrose miocárdica e na musculatura esquelética à avaliação anatomopatológica em um dos bezerros mortos, que apresentou degeneração e necrose em miocárdio e músculo esquelético. Uma sobredosagem de monensina (25,5 µg/g no músculo esquelético e 209,4 µg/g no fígado) foi detectada com análise por cromatografia líquida e espectrofotometria de massas, contribuindo para a confirmação do diagnóstico de intoxicação por ionóforos.(AU)
Assuntos
Animais , Bovinos , Doenças dos Bovinos , Aditivos Alimentares/efeitos adversos , Ionóforos/efeitos adversos , Intoxicação/veterináriaResumo
Background: Perinatal mortality in sheep is determined by death between 60 days of gestation and 28 days postpartum. The starvation / hypothermia complex was characterized by lambs that walked, but did not feed. Polioencephalomalacia (PEM) is a descriptive term that indicates the morphological diagnosis for necrosis with softening of the gray matter in the brain. There are no data available in the literature relating PEM to the starvation / hypoglycemia / hypothermia complex in small ruminants. Thus, the objective of this work is to report a case of polyioencephalomalacia related to the starvation / hypoglycemia / hypothermia and septicemia complex in a newborn sheep. Case: A 5-day-old sheep female mixed race (Dorper x Santa Inês), 3.0 kg, from a rural property in the Federal District, was sent to the Veterinary Pathology Laboratory of the University of Brasília, for a necropsy. Organ fragments were collected and fixed in a 10 % buffered formalin solution, routinely processed for histology and stained with Hematoxylin and Eosin (HE). Additionally, swabs from the meninges, eyeballs and navels were collected for bacteriology. The animal came from twin pregnancies and was weak since birth. With three days of life, it presented apathy, weakness, difficulty in breastfeeding, difficulty in walking, and decubitus in a self-auscultation position. After 2 days of evolution the lamb died. Macroscopically, eyeball opacity, omphalophlebitis and congested brain were observed. Microscopically in the frontal cortex, the leptomeninge was markedly thickened by a large number of neutrophils and, to a lesser extent, macrophages, lymphocytes and plasmocytes, associated with aggregates of free eosinophilic rods or in the cytoplasm of macrophages. In the underlying gray substance, the neurópilo was observed containing...(AU)
Assuntos
Animais , Feminino , Animais Recém-Nascidos , Ovinos/anormalidades , Mortalidade Perinatal , Encefalomalacia/veterinária , Necrose/veterinária , Morte Encefálica/veterinária , Doenças do Sistema Nervoso/veterináriaResumo
Background: Perinatal mortality in sheep is determined by death between 60 days of gestation and 28 days postpartum. The starvation / hypothermia complex was characterized by lambs that walked, but did not feed. Polioencephalomalacia (PEM) is a descriptive term that indicates the morphological diagnosis for necrosis with softening of the gray matter in the brain. There are no data available in the literature relating PEM to the starvation / hypoglycemia / hypothermia complex in small ruminants. Thus, the objective of this work is to report a case of polyioencephalomalacia related to the starvation / hypoglycemia / hypothermia and septicemia complex in a newborn sheep. Case: A 5-day-old sheep female mixed race (Dorper x Santa Inês), 3.0 kg, from a rural property in the Federal District, was sent to the Veterinary Pathology Laboratory of the University of Brasília, for a necropsy. Organ fragments were collected and fixed in a 10 % buffered formalin solution, routinely processed for histology and stained with Hematoxylin and Eosin (HE). Additionally, swabs from the meninges, eyeballs and navels were collected for bacteriology. The animal came from twin pregnancies and was weak since birth. With three days of life, it presented apathy, weakness, difficulty in breastfeeding, difficulty in walking, and decubitus in a self-auscultation position. After 2 days of evolution the lamb died. Macroscopically, eyeball opacity, omphalophlebitis and congested brain were observed. Microscopically in the frontal cortex, the leptomeninge was markedly thickened by a large number of neutrophils and, to a lesser extent, macrophages, lymphocytes and plasmocytes, associated with aggregates of free eosinophilic rods or in the cytoplasm of macrophages. In the underlying gray substance, the neurópilo was observed containing...
Assuntos
Feminino , Animais , Animais Recém-Nascidos , Encefalomalacia/veterinária , Mortalidade Perinatal , Ovinos/anormalidades , Doenças do Sistema Nervoso/veterinária , Morte Encefálica/veterinária , Necrose/veterináriaResumo
A prata é um elemento usado amplamente pelas suas propriedades antimicrobianas. O uso indiscriminado de antimicrobianos na produção piscícola é cada vez maior o que induz a resistência bacteriana e impactos negativos no meio ambiente. A procura de alternativas para o tratamento de bacterioses é necessária sendo preciso estudas todas as variáveis e efeitos que estes possam gerar no animal e ambiente. No presente ensaio foram estudadas as alterações teciduais induzidas no tambaqui (Colossoma macropomum) pela exposição aguda à prata coloidal.