TY - JOUR KW - calf KW - bone marrow depletion KW - haemorrhage KW - thrombocytopenia KW - circovirus AU - E Kappe AU - Y Halami AU - B Schade AU - M Alex AU - D Hoffmann AU - A Gangl AU - K Meyer AU - W Dekant AU - B-A Schwarz AU - R Johne AU - J Buitkamp AU - J Böttcher AU - H Müller AB - Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS). Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals. This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS. BT - Berliner und Münchener Tierärztliche Wochenschrift C1 - {"oldId":69757,"title":"Bone marrow depletion with haemorrhagic diathesis in calves in Germany: Characterization of the disease and preliminary investigations on its aetiology","topline":"","teaserText":"","content":"

Summary<\/span>
Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS).
Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals.
This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS.

Keywords:<\/span>
calf, bone marrow depletion, haemorrhage, thrombocytopenia, circovirus



Zusammenfassung<\/span>
Seit 2007 wird bei K\u00e4lbern in ganz Deutschland eine neue, meist t\u00f6dlich verlaufende h\u00e4morrhagische Diathese beobachtet. Die Erkrankung wurde anhand von 56 Sektionsf\u00e4llen charakterisiert. Die K\u00e4lber erkrankten durchweg im ersten Lebensmonat. Es handelte sich in der Regel um Einzeltiererkrankungen, wobei verschiedene Rassen und Tiere beiderlei Geschlechts betroffen waren. Hauptbefunde bei allen Tieren waren massive Blutungen, die vornehmlich in Haut, Unterhaut und im Gastrointestinaltrakt zu finden waren. Histologisch wurde immer eine hochgradige Hypo- bis Atrophie des Knochenmarks festgestellt. Zus\u00e4tzlich konnten eine Lymphozytendepletion (43 %) und entz\u00fcndliche Ver\u00e4nderungen (bei 46 % der Tiere) beobachtet werden. Blutanalysen von f\u00fcnf Tieren zeigten eine aplastische An\u00e4mie. Damit wird dieses H\u00e4morrhagische Diathese Syndrom (HDS) haupts\u00e4chlich durch eine Thrombozytopenie verursacht.
Abstammungsanalysen ergaben keinen Hinweis auf eine Erbkrankheit. Toxine wie z. B. S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), Furazolidon oder Mykotoxine, die Knochenmarkssch\u00e4den hervorrufen k\u00f6nnen, wurden nicht nachgewiesen. Auch Infektionen mit Bakterien oder mit dem Virus der Bovinen Virus Diarrhoe (BVDV) sowie der Blauzungenkrankheit (BTV) wurden als Ursache ausgeschlossen. HDS hat gewisse \u00c4hnlichkeit mit Circovirusinfektionen beim Gefl\u00fcgel (Infekti\u00f6se An\u00e4mie der K\u00fcken). Mit Hilfe einer Breitspektrum-PCR konnte Circovirus-DNS bei f\u00fcnf von 25 HDS-K\u00e4lbern und einem von acht Nicht-HDS-K\u00e4lbern nachgewiesen werden. Die vollst\u00e4ndige DNS-Sequenz zeigt eine starke \u00c4hnlichkeit (bis zu 99 %) zum Porzinen Circovirus Typ 2b (PCV 2b). In einer PCV2-spezifischen Immunhistologie f\u00e4rbten sich einzelne Knochenmarkszellen bei einem von acht HDS-K\u00e4lbern schwach positiv.
Es konnte erstmals ein Circovirus bei Rindern in Deutschland nachgewiesen werden. Die Ursache des HDS bleibt jedoch unklar. Ein multifaktorielles Geschehen, an dem Infektionen, Intoxikationen, Immunopathien oder genetische Pr\u00e4disposition beteiligt sein k\u00f6nnen, ist denkbar. Es sind weitere Untersuchungen notwendig, um die Pathogenese von HDS und eine m\u00f6glichen Beteiligung von PCV2 aufzukl\u00e4ren.

Schl\u00fcsselw\u00f6rter:<\/span>
Kalb, Panmyelophthise, Thrombozytopenie, Blutungsneigung, Circovirus <\/p>","categories":["Open Access","Tier\u00e4rztliche Wochenschrift","Abostufe BMTW","Fachartikel","Abostufe frei"],"fromDate":"Dec 8, 2009 12:00:00 AM","toDate":"Dec 31, 2050 12:00:00 AM","oldUrls":["http:\/\/vetline.de\/calf-bone-marrow-depletion-haemorrhage-thrombocytopenia\/150\/3130\/69757","http:\/\/vetline.de\/calf-bone-marrow-depletion-haemorrhage-thrombocytopenia\/150\/3216\/69757"],"doiLanguage":"englisch","doiProductFormat":"Online","doiPublisher":"Schl\u00fctersche Verlagsgesellschaft mbH & Co. KG","doiSerialWorkTitle":"Berl. M\u00fcnch. Tier\u00e4rztl. Wschr.","doiDocumentUri":"http:\/\/www.vetline.de\/calf-bone-marrow-depletion-haemorrhage-thrombocytopenia\/150\/3130\/69757","doiSource":"Berl. M\u00fcnch. Tier\u00e4rztl. Wschr. 123: 1-2, 31-41 (2010)","doiissn":"0005-9366","doiNr":"10.2376\/0005-9366-123-31","doiFirstPage":"31","doiLastPage":"41","doiTransmitted":true,"doiAuthor":"Kappe EC, Halami MY, Schade B, Alex M, Hoffmann D, Gangl A, Meyer K, Dekant W, Schwarz BA, Johne R, Buitkamp J, B\u00f6ttcher J, M\u00fcller H","pdf":{"path":"http:\/\/data\/bmtw_2010_01_0031.pdf","title":"Bone marrow depletion with haemorrhagic diathesis in calves in Germany: Characterization of the disease and preli","description":""},"authors":[{"firstName":"E","middleName":"C","lastName":"Kappe"},{"firstName":"M","middleName":"Y","lastName":"Halami"},{"firstName":"B","middleName":"","lastName":"Schade"},{"firstName":"M","middleName":"","lastName":"Alex"},{"firstName":"D","middleName":"","lastName":"Hoffmann"},{"firstName":"A","middleName":"","lastName":"Gangl"},{"firstName":"K","middleName":"","lastName":"Meyer"},{"firstName":"W","middleName":"","lastName":"Dekant"},{"firstName":"B","middleName":"A","lastName":"Schwarz"},{"firstName":"R","middleName":"","lastName":"Johne"},{"firstName":"J","middleName":"","lastName":"Buitkamp"},{"firstName":"J","middleName":"","lastName":"B\u00f6ttcher"},{"firstName":"H","middleName":"","lastName":"M\u00fcller"}],"contentOptimised":"

Summary<\/strong>
Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS).
Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals.
This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS.

Keywords:<\/strong>
calf, bone marrow depletion, haemorrhage, thrombocytopenia, circovirus



Zusammenfassung<\/strong>
Seit 2007 wird bei K\u00e4lbern in ganz Deutschland eine neue, meist t\u00f6dlich verlaufende h\u00e4morrhagische Diathese beobachtet. Die Erkrankung wurde anhand von 56 Sektionsf\u00e4llen charakterisiert. Die K\u00e4lber erkrankten durchweg im ersten Lebensmonat. Es handelte sich in der Regel um Einzeltiererkrankungen, wobei verschiedene Rassen und Tiere beiderlei Geschlechts betroffen waren. Hauptbefunde bei allen Tieren waren massive Blutungen, die vornehmlich in Haut, Unterhaut und im Gastrointestinaltrakt zu finden waren. Histologisch wurde immer eine hochgradige Hypo- bis Atrophie des Knochenmarks festgestellt. Zus\u00e4tzlich konnten eine Lymphozytendepletion (43 %) und entz\u00fcndliche Ver\u00e4nderungen (bei 46 % der Tiere) beobachtet werden. Blutanalysen von f\u00fcnf Tieren zeigten eine aplastische An\u00e4mie. Damit wird dieses H\u00e4morrhagische Diathese Syndrom (HDS) haupts\u00e4chlich durch eine Thrombozytopenie verursacht.
Abstammungsanalysen ergaben keinen Hinweis auf eine Erbkrankheit. Toxine wie z. B. S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), Furazolidon oder Mykotoxine, die Knochenmarkssch\u00e4den hervorrufen k\u00f6nnen, wurden nicht nachgewiesen. Auch Infektionen mit Bakterien oder mit dem Virus der Bovinen Virus Diarrhoe (BVDV) sowie der Blauzungenkrankheit (BTV) wurden als Ursache ausgeschlossen. HDS hat gewisse \u00c4hnlichkeit mit Circovirusinfektionen beim Gefl\u00fcgel (Infekti\u00f6se An\u00e4mie der K\u00fcken). Mit Hilfe einer Breitspektrum-PCR konnte Circovirus-DNS bei f\u00fcnf von 25 HDS-K\u00e4lbern und einem von acht Nicht-HDS-K\u00e4lbern nachgewiesen werden. Die vollst\u00e4ndige DNS-Sequenz zeigt eine starke \u00c4hnlichkeit (bis zu 99 %) zum Porzinen Circovirus Typ 2b (PCV 2b). In einer PCV2-spezifischen Immunhistologie f\u00e4rbten sich einzelne Knochenmarkszellen bei einem von acht HDS-K\u00e4lbern schwach positiv.
Es konnte erstmals ein Circovirus bei Rindern in Deutschland nachgewiesen werden. Die Ursache des HDS bleibt jedoch unklar. Ein multifaktorielles Geschehen, an dem Infektionen, Intoxikationen, Immunopathien oder genetische Pr\u00e4disposition beteiligt sein k\u00f6nnen, ist denkbar. Es sind weitere Untersuchungen notwendig, um die Pathogenese von HDS und eine m\u00f6glichen Beteiligung von PCV2 aufzukl\u00e4ren.

Schl\u00fcsselw\u00f6rter:<\/strong>
Kalb, Panmyelophthise, Thrombozytopenie, Blutungsneigung, Circovirus <\/p>","primaryLanguage":"englisch","summary":"Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS).
Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals.
This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS.","keywords":["calf","bone marrow depletion","haemorrhage","thrombocytopenia","circovirus"],"zusammenfassung":"Seit 2007 wird bei K\u00e4lbern in ganz Deutschland eine neue, meist t\u00f6dlich verlaufende h\u00e4morrhagische Diathese beobachtet. Die Erkrankung wurde anhand von 56 Sektionsf\u00e4llen charakterisiert. Die K\u00e4lber erkrankten durchweg im ersten Lebensmonat. Es handelte sich in der Regel um Einzeltiererkrankungen, wobei verschiedene Rassen und Tiere beiderlei Geschlechts betroffen waren. Hauptbefunde bei allen Tieren waren massive Blutungen, die vornehmlich in Haut, Unterhaut und im Gastrointestinaltrakt zu finden waren. Histologisch wurde immer eine hochgradige Hypo- bis Atrophie des Knochenmarks festgestellt. Zus\u00e4tzlich konnten eine Lymphozytendepletion (43 %) und entz\u00fcndliche Ver\u00e4nderungen (bei 46 % der Tiere) beobachtet werden. Blutanalysen von f\u00fcnf Tieren zeigten eine aplastische An\u00e4mie. Damit wird dieses H\u00e4morrhagische Diathese Syndrom (HDS) haupts\u00e4chlich durch eine Thrombozytopenie verursacht.
Abstammungsanalysen ergaben keinen Hinweis auf eine Erbkrankheit. Toxine wie z. B. S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), Furazolidon oder Mykotoxine, die Knochenmarkssch\u00e4den hervorrufen k\u00f6nnen, wurden nicht nachgewiesen. Auch Infektionen mit Bakterien oder mit dem Virus der Bovinen Virus Diarrhoe (BVDV) sowie der Blauzungenkrankheit (BTV) wurden als Ursache ausgeschlossen. HDS hat gewisse \u00c4hnlichkeit mit Circovirusinfektionen beim Gefl\u00fcgel (Infekti\u00f6se An\u00e4mie der K\u00fcken). Mit Hilfe einer Breitspektrum-PCR konnte Circovirus-DNS bei f\u00fcnf von 25 HDS-K\u00e4lbern und einem von acht Nicht-HDS-K\u00e4lbern nachgewiesen werden. Die vollst\u00e4ndige DNS-Sequenz zeigt eine starke \u00c4hnlichkeit (bis zu 99 %) zum Porzinen Circovirus Typ 2b (PCV 2b). In einer PCV2-spezifischen Immunhistologie f\u00e4rbten sich einzelne Knochenmarkszellen bei einem von acht HDS-K\u00e4lbern schwach positiv.
Es konnte erstmals ein Circovirus bei Rindern in Deutschland nachgewiesen werden. Die Ursache des HDS bleibt jedoch unklar. Ein multifaktorielles Geschehen, an dem Infektionen, Intoxikationen, Immunopathien oder genetische Pr\u00e4disposition beteiligt sein k\u00f6nnen, ist denkbar. Es sind weitere Untersuchungen notwendig, um die Pathogenese von HDS und eine m\u00f6glichen Beteiligung von PCV2 aufzukl\u00e4ren.","schluesselwoerter":["Kalb","Panmyelophthise","Thrombozytopenie","Blutungsneigung","Circovirus"],"translatedTitle":"","abstractE":"Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS). Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals. This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS.","date":{"year":2009,"date":"12\/2009","accepted":"2009-12-08"},"volume":"123","openAccess":true,"journal":"Berliner und M\u00fcnchener Tier\u00e4rztliche Wochenschrift","titleImageId":944,"pages":"31-41","redirects":["calf-bone-marrow-depletion-haemorrhage-thrombocytopenia\/150\/3130\/69757","calf-bone-marrow-depletion-haemorrhage-thrombocytopenia\/150\/3216\/69757"],"tierartCategories":[],"artikelartCategories":["Open Access","Tier\u00e4rztliche Wochenschrift","Abostufe BMTW","Fachartikel","Abostufe frei"]} CY - Hannover DA - 12/2009 DO - 10.2376/0005-9366-123-31 LA - English N2 - Since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of Germany. Analysis of 56 cases submitted for necropsy allowed its characterization. Calves fell ill within the first month of life independent of breed and sex. Only single or a few animals per herd were affected. Petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. Microscopically a severe depletion of bone marrow cells was always observed. Lymphocytic depletion (43%) and inflammatory lesions (46%) were less frequently observed. Blood analysis of five animals indicated an aplastic pancytopenia. The resulting thrombocytopenia is regarded as major pathomechanism of this Haemorrhagic Disease Syndrome (HDS). Pedigree analysis gave no indication of hereditary disease. Tests for specific toxins such as S-(1,2-Dichlorovinyl)-L-cysteine (DCVC), furazolidone, or mycotoxins resulting in bone marrow depletion were negative. Bacterial infections, Bovine Viral Diarrhoea Virus, and Bluetongue Virus were ruled out as cause of the disease. HDS shares similarities with a circoviral infection in chickens (chicken infectious anaemia). A broad-spectrum PCR allowed detection of circoviral DNA in 5 of 25 HDS cases and in 1 of 8 non-HDS cases submitted for necropsy. Sequencing of the whole viral genome revealed a high similarity (up to 99%) with Porcine Circovirus type 2b. Single bone marrow cells stained weakly positive for PCV2 antigen by immunohistochemistry in 1of 8 tested HDS animals. This is the first report of circovirus detection in cattle in Germany. The exact cause of HDS still remains unknown. A multifactorial aetiology involving infection, poisoning, immunopathy, or a genetic predisposition is conceivable. Additional research is necessary to clarify the pathogenesis and the potential role of PCV2 in HDS. PB - Schlütersche Verlagsgesellschaft mbH & Co. KG PP - Hannover PY - 2009 SP - 31 EP - 41 T1 - Bone marrow depletion with haemorrhagic diathesis in calves in Germany: Characterization of the disease and preliminary investigations on its aetiology T2 - Berliner und Münchener Tierärztliche Wochenschrift TI - Bone marrow depletion with haemorrhagic diathesis in calves in Germany: Characterization of the disease and preliminary investigations on its aetiology VL - 123 SN - 0005-9366 ER -