Necropsied Sheep Research Articles

Pneumopatia tóxica por Trema micrantha em ovinos no Estado de Santa Catarina, Brasil

ABSTRACT: Poisoning by Trema micrantha commonly causes hepatocellular necrosis in cattle, sheep, and goats and edema and cerebral hemorrhage in horses. This plant can cause toxic pneumopathy in sheep, and there is only one report of the natural form and one of the experimental form in the State of Rio Grande do Sul. This study aimed to report an outbreak of the respiratory form of natural poisoning by T. micrantha in sheep. Six sheep developed clinical respiratory signs after consumption of the plant and four of them died and two recovered after treatment with dexamethasone. The sheep presented tachypnea, noisy breathing, edema of the face, eyelids, and vulva, and subcutaneous emphysema on the face and neck. Necropsy (Sheep 2, 3, and 4) showed uncollapsed, heavy, diffuse red lungs with evident costal impressions and a moderate amount of serosanguineous fluid flowed at section. The liver had a moderate diffuse evident lobular pattern. The histopathology of the lungs of the three necropsied sheep showed congestion and edema with the formation of hyaline membranes within accentuated diffuse alveoli, in addition to thickening of the alveolar septa due to mild to moderate diffuse type II pneumocyte hyperplasia and also mild to moderate diffuse infiltrate of macrophages, lymphocytes, plasma cells, and neutrophils in the lumen of alveoli, bronchi, and bronchioles. Sheep 3 also showed type II pneumocytes with enlarged and hyperchromatic nuclei, sometimes binucleated with evident nucleoli, and, in some regions, the pneumocytes were desquamated to the alveolar lumen forming small syncytia and mild multifocal hyperplasia in the bronchial epithelium. The anti-cytokeratin IHC evaluation showed marked diffuse intracytoplasmic staining in hyperplastic type II pneumocytes in the bronchiolar epithelium of the three evaluated sheep. The liver of the three sheep had mild multifocal centrilobular necrosis. It seems to be the second report of spontaneous poisoning by T. micrantha in sheep developing lung lesions described in Brazil and the first in the State of Santa Catarina.

Investigating peste des petits ruminants (PPR) in naturally infected goats and sheep in Anseba Region, Eritrea, by reverse transcription polymerase chain reaction (RT-PCR).

The impact of peste des petits ruminants (PPR) virus was investigated by reverse transcription polymerase chain reaction (RT-PCR) on different samples obtained from non-vaccinated diseased and necropsied sheep and goats showing PPR-like symptoms. The disease picture was typical and sheep were observed to be less susceptible. Nasal and rectal swabs, whole blood and pathological tissue samples from the lungs, intestine, and mesenteric lymph nodes were used for this study. The results of RT-PCR indicated that from a total of 32 samples collected, 12 (41%) were positive by this method. Out of those collected samples, 29 were from goats and 3 were from sheep. Nasal and rectal swabs and blood samples were superior in detection of the PPR virus compared to other tissue samples.

Experimental poisoning by Vernonia rubricaulis in sheep

In order to evaluate the susceptibility of sheep to V. rubricaulis and to establish the clinical signs, serum biochemistry, and pathological findings, eight sheep were fed varying doses of V. rubricaulis. The onset of clinical signs occurred 6–48 h after the ingestion of V. rubricaulis. Clinical courses lasted 6–56 h after the ingestion of the plant. Serum activities of aspartate aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase were highly elevated and glucose blood levels were low in affected sheep. Clinical signs consisted of apathy, anorexia, dry muzzle, respiratory distress, abdominal pain, and mushy feces with streaks of blood and mucus. Two sheep had neurological signs including muscle fasciculation, nystagmus, paddling movements, and blindness. Liver necrosis could be detected antemortem through liver biopsy. Five sheep died and three recovered. The liver was affected in all necropsied sheep; it increased in volume and had marked accentuation of the lobular pattern with red, depressed areas intercalated with a pale yellow network. Ascites and hydropericardium were consistent findings. Microscopically, centrilobular to massive coagulative necrosis was observed. Coagulative necrosis was also observed in a few proximal renal tubules. Microscopic lesions were not found in any other organs. The severity of liver lesions was proportional to the dose. Chemical analysis to detect carboxyatractyloside in V. rubricaulis plant material was negative. It is concluded that V. rubricaulis poisoning in sheep is clinically, biochemically, and pathologically characteristic of an acute hepatoxicosis.

Diagnoses of Ovine Infection by the Serotype-4 Bluetongue Virus on Minas Gerais, Brazil

Background: Bluetongue (BT) is a viral disease transmitted by hematophagous vectors of the genus Culicoides. In Brazil, the identifcation of antibodies against the virus has been held for over thirty years, however clinicopathological diagnosis of the disease are scarce. The frst reported case occurred in the state of Paraná in 2001, confrmed by isolation and identifcation of serotype 12 of BTV. In the state of Rio Grande do Sul, in 2009, two outbreaks confrmed and was identifed the serotype 12. Serotype 4 was isolated during an outbreak in the state of Rio de Janeiro in 2013. This study describes the Diagnoses of ovine infection by the serotype-4 bluetongue virus in Minas Gerais, Brazil. Case: In a farm in the Southern region of the state of Minas Gerais, a group of 28 male sheep, was sent for necropsy at the Setor de Patologia Veterinária of Universidade Federal de Lavras (SPV-UFLA). In a flock of 80 male sheep 28 died with clinical signs of respiratory distress, whereas other showed signs of anemia and hypoproteinemia, cough, sneezing, prostration, fever, mucopurulent nasal discharge, anemia and submandibular edema. At necropsy, the main changes observed were cranioventral pulmonary consolidation, hemorrhage at the base of the pulmonary artery and ulcerating lesions in the hard palate mucosa, rumen and reticulum. The histological changes consisted of bacterial bronchopneumonia, papillary necrosis associated with bacterial structures, multifocal vasculitis in the submucosa and thrombi in blood vessels of the serosa in the rumen and reticulum, hyaline and flocculate necrosis in esophageal muscle, skeletal and cardiac muscle fbers were also observed, associated with moderate mononuclear inflammatory infltrate between fbers and around blood vessels. Discussion: The diagnosis of BT was confrmed by the identifcation of nucleic acids of the virus in blood samples and from tissues of animals from the herd by RT-PCR and by the detection of antibodies against Bluetongue virus with the agar gel immunodiffusion (AGID) test using serum samples from the remaining herd animals. Serotype 4 was identifed in three of the samples inoculated into KC cells. The hemorrhage at the base of the pulmonary artery, one characteristic fndings, was found in three of the necropsied sheep. The pulmonary lesions observed in the present study strongly suggest the occurrence of pneumonia caused by opportunistic bacteria, especially Mannheimia haemolytica, which is commonly associated with pneumonia in sheep infected with BTV. This work is the frst in the state of Minas Gerais and the fourth in Brazil to report an outbreak of the disease with clinical signs. The economic impact of bluetongue results not only from the direct losses of animals to the disease, but also to the correlation among BTV infection and other problems including pneumonia, abortion and verminoses. In a study focused on the characteristics of ovine farming in Minas Gerais, farmers from the center-southwest reported that abortion and pneumonia were among their main problems. Thus, further epidemiological studies on BTV may improve the level of identifcation of infected herds and may help promote prophylactic measures. Necropsies and histopathology exams constitute crucial tools for diagnosis, because most cases present at a sub-clinical stage or in association with other, concomitant diseases. Keywords: BTV 4, viral diseases, sheep, RT-PCR e IDGA

Outbreak of Contagious Echtyma in Sheep in Rio Grande do Sul, Brazil.

Background: Contagious ecthyma is a viral disease caused by a Parapoxvirus, which affects primarily sheep and goats. The disease has a worldwide distribution and is characterized by cutaneous pustules and crusts mainly in the muzzle and lips. Although the disease has a worldwide distribution, there are few reports in the literature of contagious ecthyma outbreaks in Brazil. Moreover, this is an important disease, as well as causing huge economic losses due to high morbidity rates, is also a zoonosis occupational character. This report describes the epidemiological, clinical, and anatomopathological aspects of an outbreak of contagious echtyma in sheep in the State of Rio Grande do Sul, Brazil. Case: Cases were observed on January and February of 2016. Seventeen out of 45 Texel sheep were affected including fve 4-6-month-old lambs, three 7-12-month-old male sheep and nine 2-year-old ewes. Before the outbreak, a Texel ram was introduced in the herd as replacement. Clinically, affected sheep had pustules, ulcers, and crusts in the lips, labial commissures, muzzle, and nasal bridge. They also presented dyspnea, submandibular and facial subcutaneous edema. One of the affected sheep was euthanized due to the poor prognosis. At necropsy, the lesions observed clinically were confrmed. Histopathology of the skin in the lips and muzzles showed marked acanthosis of the epidermis, orthokeratotic and parakeratotic hyperkeratosis of the stratum corneum, intracorneal vesicles and pustules, as well as hydropic degeneration and apoptosis of keratinocytes. This lesions led to epidermal serocellular crusting. Histologically and ultrastructurally respectively, inclusion bodies or viral particles were not observed. Approximately 45 days after the diagnosis there were no new cases of echtyma in the herd. Discussion: The diagnosis of contagious ecthyma in these sheep was based on epidemiological, clinical, and pathological fndings. In sheep and goats the disease affects mainly lambs, kids, and lactating females, although sheep from both sexes, and all breeds and ages are susceptible. In this outbreak, sheep of different categories were affected with morbidity about 37%. Carrier sheep and contaminated fomites are the main forms of transmission. In this outbreak, it is presumed that the introduction in the herd of a male carrying the virus was the source of infection to the other sheep. Clinically, it was notice a variation in the clinical signs. Initial lesions were almost imperceptible, and latest lesions were more severe, with a predominance of proliferative crusted changes in the lips and muzzle. The facial and submandibular edema in some sheep was an unusual manifestation of the disease. Gross and microscopic fndings observed in these sheep contributed to the defnitive diagnosis of the disease. Histologically, despite inclusions were not observed, hyperkeratosis, acanthosis, pustules, and degenerative and necrotic changes in the epithelium are typical lesions of contagious ecthyma. It is suggested that the viral particles and the inclusion bodies were not detected by electron microscopy and histology because the necropsied sheep presented a chronic clinical course of the disease. The association of epidemiological, clinical, and pathological fndings allowed the defnitive diagnosis of contagious ecthyma, although inclusions and viral particles were not observed. The introduction of a virus carrier was the likely source of the disease in a non-immune herd. Keywords: diseases of sheep, viral diseases, Parapoxvirus, pustular dermatitis, orf

Occurrences of Oestrus ovis parasitism in necropsied sheep in the Umuarama microregion, Paraná, Brazil.

Between January 2007 and September 2013, 71 sheep belonging to 12 farms in the Umuarama microregion, State of Paraná, were evaluated regarding presence of Oestrus ovis larvae, during necropsies. The farms from which these animals originated were visited and the owners and employees were interviewed. Occurrences of O. ovis parasitism in sheep were diagnosed for the first time on this microregion. Of the 71 animals, 12 (16.9%) were parasitized by O. ovis, with mean intensity of 2.25 larvae per infested head (1 to 8 larvae/infested head). There was a high correlation (0.81, p=0.0346) between the number of larvae and the macroscopic lesions observed in these animals' nasal cavities, such that sheep with more than 3 larvae may contain mucupurulent secretions or epistaxis. From the interviews conducted, it was found that all the farm owners were applying chemical parasite control methods (helminths and/or O. ovis), administered to all animals in the herds every 30 days (91.6% of the producers), using derivatives of macrocyclic lactones and/or benzimidazoles/imidazothiazoles. Further studies need to be conducted in this particular region, in an attempt to elucidate the prevalence of O. ovis parasitism in herds.

Doenças da cavidade nasal em pequenos ruminantes no Distrito Federal e no Estado de Goiás

Resumo As enfermidades que acometem a cavidade nasal de pequenos ruminantes podem causar prejuízos aos rebanhos de ovinos e caprinos na região central do Brasil. Foi realizado estudo retrospectivo dos laudos de necropsia do Laboratório de Patologia Veterinária da Universidade de Brasília (LPV-UnB) nos anos de 2003 a 2014 para verificar a ocorrência das doenças que acometeram a cavidade nasal de pequenos ruminantes. Foram analisados 463 protocolos de ovinos e 75 de caprinos totalizando 538 casos. Seis ovinos (6/463 1,29%) foram necropsiados com rinite granulomatosa micótica ou oomicótica e 22 animais do estudo (22/538; 4,08%) tiveram o diagnóstico de oestrose, sendo 86,36% ovinos e 13,64% caprinos. As rinites piogranulomatosas em ovinos ocorreram em áreas alagadas, com abundante material vegetal em decomposição. Os ovinos com pitiose rinofacial apresentaram como principais alterações aumento de volume na região nasal devido a extensas lesões granulomatosas associadas a necrose tecidual, caracterizadas por inúmeros macrófagos e polimorfonucleares circundando centros necróticos contendo o agente envolto por reação de Splendore-Hoeppli. Os ovinos com conidiobolomicose exibiram extensas áreas de necrose e inflamação piogranulomatosa, associadas à presença de hifas fúngicas na nasofaringe e também na região peribulbar e exoftalmia. A maioria dos animais com oestrose não apresentou alterações clínico-patológicas significativas, apesar de serem encontradas larvas principalmente nos seios e conchas nasais, traqueia e seio paranasal. A importância dessas enfermidades ainda é pouco conhecida na região, sendo de grande relevância que as condições clínico-patológicas e epidemiológicas sejam elucidadas para o diagnóstico, o controle e a prevenção, para evitar a expansão e prejuízos para os rebanhos.

Clinical and pathological aspects of chronic Senecio spp. poisoning in sheep

This paper describes an outbreak of chronic Senecio spp. poisoning in grazing sheep in Rio Grande do Sul, Brazil, causing the death of 10 out of 860 adult sheep. Eight sick ewes were euthanized and necropsied. Cattle from this farm were also affected. Clinical signs included progressive weight loss, apathy and photosensitization. Four out of seven tested sheep had increased gamma-glutamyl transferase serum activity and two of them presented serum elevation of alkaline phosphatase. At necropsy, three out of eight ewes presented slightly irregular toughened livers with multifocal nodules, two out of eight ewes had a whitish liver with thickened fibrotic Glisson's capsule partially adhered to the diaphragm, and three out of eight ewes had smooth and grossly normal livers. Necropsy findings attributed to liver failure included hydropericardium (7/8), ascites (5/8), icterus (2/8), hydrothorax (1/8), and edema of mesentery (1/8). The main hepatic histological findings that allowed the establishment of the diagnosis were megalocytosis, proliferation of bile ducts and fibrosis. Spongy degeneration was observed in the brains of all eight necropsied sheep and was more severe at the cerebellar peduncles, mesencephalon, thalamus, and pons. These are suggested as the portions of election to investigate microscopic lesions of hepatic encephalopathy in sheep with chronic seneciosis. The diagnosis of Senecio spp. poisoning was based on epidemiology, clinical signs, laboratory data, necropsy and histological findings.

Pigmentation of the viscera and carcasses (chromatosis) in sheep in the Brazilian northeastern region

We report exogenous pigmentation in sheep grazing in native pastures in northeastern Brazil. The sheep carcasses from a farm were condemned at the slaughterhouse due to pigmentation of the carcasses and viscera. In visits to the farm, bluish-purple pigmentation of the mucosa was observed in the sheep. In two necropsied sheep, a bluish-purple pigment was observed in the skin, subcutaneous tissue, fat, muscles, cartilage, bones, serous membranes of the forestomachs, kidneys, adrenal glands, and the mucosa of the uterus, urinary bladder, urethra, vagina, trachea, bronchi, and bronchioles. Some bone surfaces, the intima of large arteries, tendons, muscle insertions, and ligaments had a yellow-brown or light brown pigment. However, the pigment was not observed upon histologic examination of tissues, suggesting that the pigmentation is caused by a plant. Two plants, Rhamnidium molle and Pereskia bahiensis, were fed to experimental sheep and rabbits, but did not cause pigmentation.

Prevalence of gastrointestinal helminths, lungworms and liver fluke in sheep and goats in Norway

The present study describes the occurrence of various gastrointestinal helminths, lungworms and liver flukes in Norwegian sheep and goats as assessed from faecal samples and post mortem examinations performed between 2007 and 2010. Faecal samples for gastrointestinal nematode egg counts were collected from 77 sheep flocks and 30 dairy goat flocks from three geographical regions in Norway. Additionally, thirty-two lambs and 16 adult goats were euthanized for necropsy examination and for identification of adult gastrointestinal nematodes and tapeworms, lungworms and liver flukes. The survey showed that there was a higher mean excretion of trichostrongyle eggs in sheep than in goats at the individual level (392 EPG vs. 154 EPG, p<0.001). For both host species, the mean prevalence and intensity of excreted trichostrongyle eggs were significantly higher in the southern coastal region compared with the inland and northern regions (p<0.001). Third stage larvae of Trichostrongylus/Teladorsagia, Haemonchus and Nematodirus type were the most prevalent ones in the coprocultures from sheep, whereas larvae of Trichostrongylus/Teladorsagia and Nematodirus type dominated in goats. The most prevalent gastrointestinal nematode species found at necropsy was Teladorsagia circumcincta (75.0 and 81.2% respectively in sheep and goats), while the largest mean worm burdens were recorded for Haemonchus contortus in sheep (724±623) and T. circumcincta in goats (377±529). Other gastrointestinal nematode species were present at low prevalence or in low numbers.Fasciola hepatica was only found in necropsied sheep from the coastal region with a prevalence of 18.8%. The lungworm Mullerius capillaris was found from all regions in necropsied goats (31.2%) and from coastal area in sheep (3.1%). The present study indicates that H. contortus and Nematodirus battus have a wider geographical distribution to the north than expected, and describes to our knowledge the northernmost occurrence of H. contortus in the Nordic countries.

Seneciose crônica em ovinos no sul do Rio Grande do Sul

Descrevem-se dois surtos de intoxicação por Senecio spp. em ovinos a campo no sul do Rio Grande do Sul. A enfermidade ocorreu no ano 2006 em duas propriedades que estavam severamente invadidas pela planta e com acentuada escassez de forragem. A morbidade nos dois surtos variou de 10% a 9,5% nas duas propriedades, respectivamente. Na primeira propriedade os animais eram nascidos e criados na área e na outra os ovinos haviam sido adquiridos alguns meses antes do surto. Os sinais clínicos caracterizaram-se por emagrecimento progressivo, apatia, fraqueza, icterícia e fotossensibilização. Macroscopicamente, o fígado dos ovinos necropsiados estava aumentado de tamanho, amarelado, com superfície capsular irregular e vesícula biliar aumentada de tamanho e com edema da parede. Ao corte no fígado havia nódulos bem delimitados, esbranquiçados com 1-3mm de diâmetro. Havia, ainda, ascite e discreto edema de mesentério. Microscopicamente, as lesões hepáticas eram semelhantes em todos os fígados e caracterizadas por megalocitose, fibrose periportal, presença de hepatócitos tumefeitos, vacuolizados e de hepatócitos necróticos distribuídos aleatoriamente pelo parênquima hepático, hiperplasia das células dos ductos biliares e presença de pseudo-inclusões nos núcleos de hepatócitos. Encefalopatia hepática (status spongiosus) foi observada em todos os ovinos necropsiados. O diagnóstico foi baseado na epidemiologia, sinais clínicos, lesões macroscópicas e histológicas observadas. Concluiu-se que, apesar de a intoxicação por Senecio spp. ser pouco frequente em ovinos e essa espécie animal controlar eficientemente a planta, isso, aparentemente, depende da lotação utilizada e surtos da intoxicação podem ocorrer quando esta lotação é menor que 0,2 ovinos por hectare e há carência de forragem acentuada.

Losses of adult sheep due to ovine Johne's disease in 12 infected flocks over a 3‐year period

To measure the biological and financial impact of ovine Johne's disease (OJD) mortalities on 12 infected flocks within the endemic area of southern New South Wales over a 3-year period. An observational study was conducted over a 3-year period from 2002 to 2004 on sheep from 12 OJD-infected flocks from southern NSW. Flocks ranged from between 3,500 and 20,000 sheep. At the start of the study owner estimates of OJD mortality were 5% or greater. Annual mortality rates were estimated from farm records provided by owners. The proportion of OJD mortalities was assessed after histological examination of tissues collected from dead and moribund sheep during 5-day necropsy inspections conducted in autumn, winter, spring and summer in 2002. The financial impact was estimated using a gross margin analysis for each of the three study years and by placing a financial value on the necropsied sheep. On the 12 farms, the average OJD mortality rate was 6.2% (range 2.1% to 17.5%) in 2002, 7.8% (range 1.8% to 14.6%) in 2003 and 6.4% (range 2% to 11.9%) in 2004. The average decrease in gross margin due to OJD infection on a farm in 2002 was 6.4% (range 2.2% to 15.4%), 8.5% (range 3.1% to 15.8%) in 2003 and 7.4% (range 1.5% to 15.4%) in 2004. This equates to an average reduction in annual income of $13,715 per farm per year. OJD losses accounted on average for two thirds of the total estimated financial loss associated with sheep deaths. This study demonstrates the significant biological and financial impact of OJD on sheep flocks. These findings are of relevance to all Australian sheep flocks infected or at risk of OJD infection.

INTOXICAÇÃO EXPERIMENTAL POR Phytolacca decandra EM OVINOS

Doses únicas de 10 a 25g/kg das folhas verdes de Phytolacca decandra foram administradas oralmente a 11 ovinos. Dois desses ovinos (20 e 25g/kg) morreram 6 horas após a ingestão da planta e os outros nove adoeceram levemente e se recuperaram. Um outro ovino recebeu 4 doses diárias de 5g/kg da mesma planta. Esse ovino e outros dois usados como controles não adoeceram. Os principais sinais clínicos nos ovinos afetados foram dor abdominal, inquietação, manoteio, distúrbios respiratórios, tremores e hiperestesia. As alterações macroscópicas mais importantes em dois ovinos necropsiados estavam restritas ao sistema digestivo e consistiam de avermelhamento difuso da mucosa do rúmen, retículo, abomaso e intestino delgado. Microscopicamente, as alterações eram necrose de coagulação e microabscessos na mucosa dos pré-estômagos e presença de numerosos cristais birrefringentes na luz dos túbulos renais.

Endoparasite prevalences of the highland sheep in Ethiopia

The status of gastrointestinal parasites of sheep in the Ethiopian highlands was studied in 1988 and 1989 at five sites about 300 km apart. Nematode log eggs per gram (epg) counts varied from 0.7 to 0.8 and 0.3 to 0.5 for natural and stubble-grazed sheep, respectively. The worm counts from the abomasum and intestines of 122 necropsied sheep at Debre Berhan and Tulu Meko were low to moderate with Trichostrongylus colubriformis dominating in the count. The worm counts were highest at Tulu Meko. Few Haemonchus contortus worms were recovered from the abomasum and low counts of Fasciola hepatica were obtained from the liver of necropsied sheep. Monthly prevalences of positive nematode eggs varied from 12.6 to 49.3% and 7.1 to 50.7% for pasture-grazing and stubble-grazing sheep, respectively, with significant ( P<0.05) differences between groups within the month. While age prevalences of positive nematode eggs were significantly ( P<0.05) different in most months, sex prevalences differed only in 4 months. The least-squares means (±SE) of positive nematode log epg varied from 1.87 (±0.02) to 2.35 (±0.03) and 1.77 (±0.05) to 2.25 (±0.02) for natural and stubble-grazing groups, respectively. Naturally-grazed sheep had significantly ( P<0.05) higher positive nematode log epg than stubble-grazed sheep in most months. Monthly prevalences of positive trematode epg varied from 1.0 to 60.8% and 0.2 to 43.5% for the natural and stubble-grazing sheep, respectively, with significant ( P<0.05) differences between the two groups within the month. Certain monthly age and sex prevalences were also significantly ( P<0.05) different within months in both natural and stubble-grazing sheep. In the necropsied sheep, the seasonal prevalences of Dictyocaulus filaria and Trichostrongylus colubriformis were 66.7–100.0% and 64.0–100.0%, respectively. Trichostrongylus axei, H. contortus, Oesophagostomum columbianum, Bunostomum trigonocephalum and Trichuris skrjabini had low prevalences.