Response of cows with osteomalacia grazing sub-tropical native pastures to phosphorus supplementation with loose mineral mix or feed blocks.

Osteomalacia outbreaks often occur in cattle grazing native pastures in regions with endemic phosphorous (P) deficiency. This study evaluated the responses of two groups of cows, initially with clinical signs of chronic P deficiency, to P supplements (100 g P/kg) offered ad libitum for 13 weeks as a loose mineral mix (LMM group) or the same mineral mix offered as blocks (BMM group). Half of the cows in each group were categorized as 'with' or 'without' severe osteopenia according to a test that depended on the resistance to penetration of a needle through the left lateral process of the L4-L5 lumbar vertebra. The groups grazed two paddocks that were switched each 3 weeks. The liveweight, supplement intakes, and the P-concentrations in soil, forage, blood, and external cortical bone (ECB) of the ribs were measured. The bicarbonate-extractable P in soil was 3.5 mg/kg. The mean of total P in forage (0.95 g/kg/DM), inorganic P in serum (iP, 0.96 mmol/L), and total P in the ECB of the ribs (85 mg/mL) at the beginning of the experiment were all low and consistent with severe chronic P deficiency. The P supplementation allowed clinical recovery in 18/20 cows with their serum and ECB P and calcium approaching normal values and in the two remaining cows the only sign was abnormal gait. Cows consumed more of the LMM than BMM supplement (means 8.3 and 6.6 g P/day, respectively). After 13 weeks cows initially classified as 'with severe osteopenia' and supplemented with LMM had higher (P < 0.05) final liveweight (difference = 21.6 kg), iP (difference = 0.74 mmol/L), bone Ca (difference = 65.7 mg/mL) and bone P (difference = 26.5 mg/mL) concentrations and lower (P < 0.01) final serum Ca/iP ratio (difference = -0.65) than cows with severe osteopenia but supplemented with BMM. The treatment of severe P deficiency cows grazing P deficient sub-tropical grasslands by P supplementation for 13 weeks was more effective with LMM than BMM.

Apoptotic bone cells may be engulfed by osteoclasts during alveolar bone resorption in young rats.

The alveolar bone is a suitable in vivo physiological model for the study of apoptosis and interactions of bone cells because it undergoes continuous, rapid and intense resorption/remodelling, during a long period of time, to accommodate the growing tooth germs. The intensity of alveolar bone resorption greatly enhances the chances of observing images of the extremely rapid events of apoptosis of bone cells and also of images of interactions between osteoclasts and osteocytes/osteoblasts/bone lining cells. To find such images, we have therefore examined the alveolar bone of young rats using light microscopy, the TUNEL method for apoptosis, and electron microscopy. Fragments of alveolar bone from young rats were fixed in Bouin and formaldehyde for morphology and for the TUNEL method. Glutaraldehyde-formaldehyde fixed specimens were processed for transmission electron microscopy. Results showed TUNEL positive round/ovoid structures on the bone surface and inside osteocytic lacunae. These structures--also stained by hematoxylin--were therefore interpreted, respectively, as osteoblasts/lining cells and osteocytes undergoing apoptosis. Osteoclasts also exhibited TUNEL positive apoptotic bodies inside large vacuoles; the nuclei of osteoclasts, however, were always TUNEL negative. Ultrathin sections revealed typical apoptotic images--round/ ovoid bodies with dense crescent-like chromatin--on the bone surface, corresponding therefore to apoptotic osteoblasts/lining cells. Osteocytes also showed images compatible with apoptosis. Large osteoclast vacuoles often contained fragmented cellular material. Our results provide further support for the idea that osteoclasts internalize dying bone cells; we were however, unable to find images of osteoclasts in apoptosis.

Scrapie diagnosis in a goat and four Santa Inês sheep from the same herd in Brazil / Diagnóstico de scrapie em um caprino e quatro ovinos Santa Inês de um mesmo rebanho no Brasil

Scrapie is a fatal and progressive transmissible spongiform encephalopathy (TSE) of natural occurrence in sheep and goats. The suspicion of scrapie may be based on clinical signs; however, the detection of pathological features of the prionic protein (PrP) in target tissues is necessary to diagnose the disease. The presence of an abnormal protein form (PrPSc) in lymphoreticular and nervous tissues is an important characteristic in diagnosis. This paper reports a case of scrapie in a flock of 55 Suffolk crossbred sheep, 19 Santa Inês sheep and 21 goats in the Mato Grosso state, midwestern Brazil. The animals were euthanized after the confirmation of a scrapie case with clinical signs in a Suffolk sheep in the same farm...

Scrapie é uma encefalopatia espongiforme transmissível (EET) progressiva e fatal de ocorrência natural em ovinos e caprinos. A suspeita de scrapie é baseada nos sinais clínicos, porém a manifestação patológica da proteína priônica (PrP) nos tecidos-alvo é necessária para a confirmação da doença. A presença de uma forma anormal da proteína (PrPSc) em tecido linforreticular e tecido nervoso constitui uma característica importante para o diagnóstico. Este trabalho é o relato de um foco de scrapie ocorrido em rebanho com 55 ovinos mistos Suffolk, 21 caprinos e 19 ovinos Santa Inês, na região Centro-Oeste do Brasil. Os animais foram eutanasiados após a confirmação de um caso de scrapie com sinais clínicos em um ovino Suffolk nessa propriedade...

Utilização da técnica de imuno-histoquímica para confirmar casos de pitiose cutânea equina diagnosticados por meio de caracterização clínica e avaliação histopatológica / Immunohistochemistry analysis to confirm cases of cutaneous pythiosis in horses diagnosed by means of clinic characterization and histopathologic evaluation

Avaliaram-se 12 feridas granulomatosas em membros torácicos e pélvicos de equinos da raça Pantaneira. Foi realizado diagnóstico sugestivo para pitiose cutânea de acordo com as características clínicas das feridas e avaliação histopatológica, com as colorações de hematoxilina-eosina (HE) e Prata Metenamina de Grocott (GMS). A confirmação do diagnóstico foi realizada por exame imuno-histoquímico, método streptavidina-biotina marcada (LSAB). O diagnóstico histopatológico foi de dermatite piogranulomatosa, focal extensa, acentuada, associada a "pseudo-hifas" características de Pythium insidiosum (pitiose cutânea), nos 12 animais desta pesquisa. O diagnóstico de pitiose foi confirmado em 100% dos casos pela imunomarcação positiva (LSAB) para Pythium insidiosum, caracterizada pela visualização de estruturas ramificadas e septadas, sendo observados 100% de paridade entre as técnicas. É possível concluir que a caracterização clínica das feridas granulomatosas com aspecto de pitiose em equinos associada ao resultado histopatológico sugestivo para pitiose equina constituem métodos de diagnóstico confiáveis, os quais podem ser confirmados pela técnica de imuno-histoquímica.

Twelve granulomatous lesions in the thoracic and pelvic limbs of horses from pantaneira breed were evaluated. It was performed suggestive diagnostic of cutaneous pythiosis according to the clinic characteristics of the lesions and histopathological exams using hematoxylin and eosin (HE) and Grocott's methenamine silver (GMS) stains. The confirmation of the diagnoses was performed by the labelled streptavidin biotin (LSAB) method (immunohistochemistry). Extensive focal pyogranulomatous dermatitis associated with "pseudo hyphae" characteristic of Pythium insidiosum (subcutaneous pythiosis) was the histopathological diagnosis for all 12 horses used in this study. It was confirmed in 100% of the cases by the positive result to Pythium insidiosum in the immunohistochemistry exam, characterized by the visualization of branched and septated structures. It was observed 100% of parity between the techniques. We can conclude that clinical characterization of the granulomatous lesions with pythiosis aspects in horses associated with histopathology suggestive of equine pythiosis constitute a reliable method of diagnostic that can be confirmed by immunohistochemistry technique.

Achados patológicos e imuno-histoquímicos em bovinos com doença granulomatosa sistêmica pelo consumo de Vicia villosa (Leg. Papilionoideae) no Rio Grande do Sul / Pathological and immunohistochemical findings in cattle affected by systemic granulomatous disease by consumption Vicia villosa (Leg. Papilionoideae) in Rio Grande do Sul

A doença granulomatosa sistêmica associada ao consumo de Vicia villosa (Leg. Papilionoideae) foi diagnosticada em 5 bovinos no período de 2005 a 2008. Os bovinos apresentavam alopecia, lesões crostosas na pele, prurido, febre, queda da produção leiteira, anorexia e emagrecimento. O curso clínico médio da doença foi de 2 semanas. Dos bovinos analisados três morreram e dois foram eutanasiados. As lesões macroscópicas de alopecia e crostas na pele eram localizadas principalmente na face e pescoço. Observava-se nódulos multifocais a coalescentes branco-acinzentados que infiltravam vários órgãos especialmente em linfonodos, rins e coração. As lesões microscópicas consistiam na infiltração de linfócitos, macrófagos, células epitelioides, células gigantes multinucleadas, eosinófilos e plasmócitos. Linfonodos, rins, adrenal, baço e fígado de todos os bovinos apresentaram infiltrado granulomatoso, porém de intensidade variável. Nos testes imuno-histoquímicos dos órgãos com infiltrado inflamatório, as principais células visualizadas foram os linfócitos T, seguidos de macrófagos/células epitelioides/células gigantes multi-nucleadas e os linfócitos B foram raramente detectados nos locais de inflamação granulomatosa. O número reduzido de células marcadas por Ki-67 nas lesões granulomatosas, tende a indicar que a proliferação celular não foi responsável pela hipercelularidade das lesões e que o recrutamento de macrófagos e linfócitos para o local da inflamação provavelmente tenha sido o responsável pelo acúmulo de células no infiltrado inflamatório.

The systemic granulomatous disease associated with consumption of Vicia villosa (Leg. Papilionoideae family) has been diagnosed in 5 cattle from 2005 to 2008. Affected cattle showed alopecia, crusted lesions on the skin, had itching, fever, decreased milk yield, anorexia and wasting. Average clinical course was 2 weeks. Three cattle died and two were euthanized in extremis. The main gross changes are alopecic and crusts in the skin, mainly on the face and neck. There also were multifocal to coalescent whitish nodules that infiltrated several organs, but especially lymph nodes, kidneys and hearth. Microscopic changes consisted of infiltration with lymphocytes, macrophages, epithelioid cells, giant multinucleated cells, eosinophils, and plasmocytes. Lymph nodes, kidneys, adrenal gland, spleen and liver from affected cattle showed varying degrees of granulomatous infiltration. Immunohistochemical procedures on samples from affected organs revealed that T-lymphocytes and macrophages/epithelioid cells/giant multinucleated cells were the main components of the inflammatory infiltrates, B-lymphocytes were only rarely seen within. The reduced numbers of cells marked by Ki-67 in the granulomatous lesions would indicate that cell proliferation was not responsible for the hypercellularity in the lesions and that rather the recruitment of macrophages and lymphocytes to the site inflammation probably accounted for the building up of the local cellular inflammatory infiltrate.

Intoxicação aguda com sementes de Crotalaria spectabilis (Leg. Papilionoideae) em suínos / Acute poisoning with Crotalaria spectabilis (Leg. Papilionoideae) seeds in pigs

Relata-se necrose hepatocelular em suínos após consumo de ração que continha grãos de sorgo-granífero (Sorghum bicolor) acidentalmente contaminado com sementes de Crotalaria spectabilis. Morreram 76 suínos em quatro propriedades no município de Juscimeira, MT. Os sinais clínicos iniciaram-se 24-48 horas após o consumo da ração contaminada e foram caracterizados por depressão, letargia, apatia, inapetência, vômito, mucosas ictéricas ou pálidas, ascite, decúbito esternal, decúbito lateral com movimentos de pedalagem e convulsões, a evolução clínica foi de 48-60 horas seguida de morte. As Principais alterações macroscópicas foram fígado aumentado de tamanho com evidenciação do padrão lobular, ascite e hidrotórax com líquido de coloração amarelo avermelhado contendo filamentos com aspecto de fibrina, linfonodos aumentados e edema pulmonar interlobular. A doença foi reproduzida utilizando-se 16 suínos divididos em seis grupos que receberam sementes de C. spectabilis em diferentes doses. Necrose hepatocelular ocorreu em sete suínos, sendo dois que receberam doses diárias 2,5g/kg e cinco que receberam doses únicas de 5,0 e 9,5g/kg. Dez doses diárias de 0,5 e 1,25g/kg causaram fibrose hepática.

Hepatocellular necrosis are reported in swine after consumption of diets containing grains of "sorgo-granífero" (Sorghum bicolor) accidentally contaminated with Crotalaria spectabilis seeds in the municipality of Juscimeira, MT. Clinical signs began 24-48 hours after consumption of contaminated ration and were characterized by depression, lethargy, apathy, loss of appetite, vomiting, pale or jaundiced mucous membranes, ascites, lateral recumbency, the lateral position with paddling and convulsions, clinical outcome was 48-60 hours followed by death. 76 pigs died in four properties. The main gross lesions were liver increased in size and lobular illustration with red-brown central areas interspersed with yellowish areas, ascites and hydrothorax with reddish-yellow liquid containing filaments with aspect of fibrin, enlarged lymph nodes and interlobular pulmonary edema. The disease was experimentally reproduced with 16 pigs divided into six groups that received seeds of C. spectabilis in different doses. Hepatocellular necrosis occurred in seven pigs, two of which received daily doses of 2.5g/kg and five who received single doses of 5 and 9.5g/ kg. Ten daily doses of 0.5 and 1.25g/kg caused liver fibrosis.

Combined TUNEL and TRAP methods suggest that apoptotic bone cells are inside vacuoles of alveolar bone osteoclasts in young rats.

Although it is generally accepted that osteoclasts breakdown and resorb bone matrix, the possibility that they may also be able to engulf apoptotic osteoblasts/lining cells and/or osteocytes remains controversial. Apoptosis of osteoblasts/ lining cells and/or osteocytes and interactions between these cells and osteoclasts are extremely rapid events that are difficult to observe in vivo. A suitable in vivo model for studying these events is the alveolar bone of young rats because it is continuously undergoing intense resorption/remodeling. Thus, sections of aldehyde fixed alveolar bone of young rats were stained by the combined terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method and the tartrate-resistant acid phosphatase (TRAP) method for the simultaneous visualization of apoptotic cells and osteoclasts in the same section. The combined TUNEL and TRAP reactions, in the same section, greatly facilitated visualization of relationship between osteoclasts and apoptotic bone cells during alveolar bone remodeling. Our results showed that several TRAP-positive osteoclasts exhibited large vacuoles containing TUNEL positive apoptotic structures, probably derived from osteoblasts/lining cells and/or osteocytes. These results support the idea that alveolar bone osteoclasts are able to internalize dying apoptotic bone cells.