PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Grecco F.B., Schild A.L., Soares M.P., Raffi M.B., Sallis E.S.V. & Damé M.C. 2009. [Organophosphate poisoning in buffaloes (Bubalus bubalis) in southern Brazil.] Intoxicação por organofosforados em búfalos (Bubalus bubalis) no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(3):211-214. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br This paper describes organophosphate (ORF) poisoning in a herd of water buffaloes (Bubalus bubalis) in southern Brazil, which were treated with a single dose of 12mg/kg body weight of Expertan® pour-on (chlorpyriphos) to control ectoparasites. Clinical signs, observed 7-45 days after exposure, were diarrhea, hypersalivation, ataxia, muscular tremors, weakness of pelvic limbs, paresis and flaccid paralysis and lateral recumbence. Out of 267 buffaloes 61 died. Necropsy of three animals that died 24-72 hours after onset of clinical signs, revealed congestion and serosal hemorrhages scattered along the bowel, emphysema and edema of the lungs. No significant histopathological changes were found. Residues of chlorpyriphos were detected in liver, kidneys and nervous system of the one necropsied buffalo. Despite the absence of histological lesions in the central and peripheral nervous system, the epidemiological, clinical, gross and toxicological findings suggest delayed neurotoxicity induced by organophosphates.

• Diseases of water buffaloes poisoning organophosphate toxicosis

Abstract in Portuguese:

ABSTRACT.- Grecco F.B., Schild A.L., Soares M.P., Raffi M.B., Sallis E.S.V. & Damé M.C. 2009. [Organophosphate poisoning in buffaloes (Bubalus bubalis) in southern Brazil.] Intoxicação por organofosforados em búfalos (Bubalus bubalis) no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(3):211-214. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br This paper describes organophosphate (ORF) poisoning in a herd of water buffaloes (Bubalus bubalis) in southern Brazil, which were treated with a single dose of 12mg/kg body weight of Expertan® pour-on (chlorpyriphos) to control ectoparasites. Clinical signs, observed 7-45 days after exposure, were diarrhea, hypersalivation, ataxia, muscular tremors, weakness of pelvic limbs, paresis and flaccid paralysis and lateral recumbence. Out of 267 buffaloes 61 died. Necropsy of three animals that died 24-72 hours after onset of clinical signs, revealed congestion and serosal hemorrhages scattered along the bowel, emphysema and edema of the lungs. No significant histopathological changes were found. Residues of chlorpyriphos were detected in liver, kidneys and nervous system of the one necropsied buffalo. Despite the absence of histological lesions in the central and peripheral nervous system, the epidemiological, clinical, gross and toxicological findings suggest delayed neurotoxicity induced by organophosphates.

Abstract in English:

ABSTRACT.- Almeida M.B., Priebe A.P.S., Riet-Correa B., Riet-Correa G., Fiss L., Raffi M.B. & Schild A.L. 2008. [Evolution and reversibility of neurologic and cardiac lesions in sheep caused by Ateleia glazioviana and Tetrapterys multiglandulosa.] Evolução e reversibiliade das lesões neurológicas e cardíacas em ovinos intoxicados experimentalmente por Ateleia glazioviana e Tetrapterys multiglandulosa. Pesquisa Veterinária Brasileira 28(3):129-134. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br To determine the reversibility of neurological and cardiac lesions in Ateleia glazioviana and Tetrapterys multiglandulosa poisoning, 3 groups of four sheep each were fed orally with the plants. In Group 1, 2 and 3, when sheep with nervous signs showed considerable increase of symptoms and risk of death, the plant administration was suspended. Group 4 with two sheep was used as control. Sheep from Group 1, fed 10g/kg during 6 days of fresh A. glazioviana collected in autumn were euthanized 8, 11, 16, and 21 days after the start of the experiment; they had shown regression of nervous signs, but had progressive cardiac lesions. Sheep from Group 2, fed during 8 days the same dose of fresh A. glazioviana collected in spring, were euthanized on days 9, 23, 38 and 68; they had shown regression of nervous signs and had no cardiac lesions. This suggests that the plant is less toxic in spring. Sheep from Group 3, fed 10g/kg during 11 days dry and ground T. multiglandulosa mixed with concentrated food, were euthanized on days 33, 33, 92 and 92; they had shown regression of nervous signs, and cardiac lesions were less severe on day 33 than on day 92. These results indicate that nervous lesions are reversible after the end of feeding, but cardiac lesions are progressive after discontinuation of the plant administration; these can be afterwards reversible if the animals do not anymore show clinical signs or die as a consequence of the poisoning. Results of those and previous experiments show that lesions of the nervous system are induced by lower doses than cardiac lesions and occur within a shorter period, what suggests that in spontaneous cases cardiac signs are always preceded by nervous signs, and that nervous signs can occur in the absence of cardiac lesions.

• Poisonous plants cardiomyopathy status spongiosus Ateleia glazioviana Tetrapterys multiglandulosa plant poisoning sheep

Abstract in Portuguese:

ABSTRACT.- Almeida M.B., Priebe A.P.S., Riet-Correa B., Riet-Correa G., Fiss L., Raffi M.B. & Schild A.L. 2008. [Evolution and reversibility of neurologic and cardiac lesions in sheep caused by Ateleia glazioviana and Tetrapterys multiglandulosa.] Evolução e reversibiliade das lesões neurológicas e cardíacas em ovinos intoxicados experimentalmente por Ateleia glazioviana e Tetrapterys multiglandulosa. Pesquisa Veterinária Brasileira 28(3):129-134. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br To determine the reversibility of neurological and cardiac lesions in Ateleia glazioviana and Tetrapterys multiglandulosa poisoning, 3 groups of four sheep each were fed orally with the plants. In Group 1, 2 and 3, when sheep with nervous signs showed considerable increase of symptoms and risk of death, the plant administration was suspended. Group 4 with two sheep was used as control. Sheep from Group 1, fed 10g/kg during 6 days of fresh A. glazioviana collected in autumn were euthanized 8, 11, 16, and 21 days after the start of the experiment; they had shown regression of nervous signs, but had progressive cardiac lesions. Sheep from Group 2, fed during 8 days the same dose of fresh A. glazioviana collected in spring, were euthanized on days 9, 23, 38 and 68; they had shown regression of nervous signs and had no cardiac lesions. This suggests that the plant is less toxic in spring. Sheep from Group 3, fed 10g/kg during 11 days dry and ground T. multiglandulosa mixed with concentrated food, were euthanized on days 33, 33, 92 and 92; they had shown regression of nervous signs, and cardiac lesions were less severe on day 33 than on day 92. These results indicate that nervous lesions are reversible after the end of feeding, but cardiac lesions are progressive after discontinuation of the plant administration; these can be afterwards reversible if the animals do not anymore show clinical signs or die as a consequence of the poisoning. Results of those and previous experiments show that lesions of the nervous system are induced by lower doses than cardiac lesions and occur within a shorter period, what suggests that in spontaneous cases cardiac signs are always preceded by nervous signs, and that nervous signs can occur in the absence of cardiac lesions.

Abstract in English:

ABSTRACT.- Soares M.P., Quevedo P.S. & Schild A.L. 2008. [Perreyia flavipes larvae poisoning in cattle in southern Rio Grande do Sul, Brazil.] Intoxicação por larvas de Perreyia flavipes em bovinos na região sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(3):169-173. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br Three outbreaks of poisoning by Perreyia flavipes Konow, 1899 (Hymenoptera: Pergidae) in cattle during July and August 2006 in southern Brazil are reported. The morbidity rate was 0.8%, 6.2% and 33% on the 3 farms, respectively. Fatality rate was 100%. Clinical signs were depression, jaundice, recumbence, pedaling movements and death in 24-48 hours. The liver was enlarged with increased lobular pattern, the mesenteric lymph nodes were edematous and Peyer patches of the small gut were depressed. Petechial hemorrhages and ecchymosis were observed in the mesentery and abomasum. On histologic examination the liver showed centrolobular or massive necrosis. Hemosiderosis and necrosis of the germinative centers of lymph nodes, white pulp of the spleen and Peyer patches were also observed. The poisoning occurred probably due to an intense drought in October-December 2005, when the insect stayed as a cocoon underground. The dry conditions probably avoided a higher number of adult sawflies to emerge from the cocoons, what resulted in greater egg production. The large amount of decaying grass due to almost normal rain fall during summer seemed to have provided favorable environmental conditions for the development of larvae in winter.

• Perreyia flavipes sawfly epidemiology bovine hepatic necrosis

Abstract in Portuguese:

ABSTRACT.- Soares M.P., Quevedo P.S. & Schild A.L. 2008. [Perreyia flavipes larvae poisoning in cattle in southern Rio Grande do Sul, Brazil.] Intoxicação por larvas de Perreyia flavipes em bovinos na região sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(3):169-173. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br Three outbreaks of poisoning by Perreyia flavipes Konow, 1899 (Hymenoptera: Pergidae) in cattle during July and August 2006 in southern Brazil are reported. The morbidity rate was 0.8%, 6.2% and 33% on the 3 farms, respectively. Fatality rate was 100%. Clinical signs were depression, jaundice, recumbence, pedaling movements and death in 24-48 hours. The liver was enlarged with increased lobular pattern, the mesenteric lymph nodes were edematous and Peyer patches of the small gut were depressed. Petechial hemorrhages and ecchymosis were observed in the mesentery and abomasum. On histologic examination the liver showed centrolobular or massive necrosis. Hemosiderosis and necrosis of the germinative centers of lymph nodes, white pulp of the spleen and Peyer patches were also observed. The poisoning occurred probably due to an intense drought in October-December 2005, when the insect stayed as a cocoon underground. The dry conditions probably avoided a higher number of adult sawflies to emerge from the cocoons, what resulted in greater egg production. The large amount of decaying grass due to almost normal rain fall during summer seemed to have provided favorable environmental conditions for the development of larvae in winter.

Abstract in English:

ABSTRACT.- Rodrigues A., De La Corte F.D., Graça D.L., Rissi D.R., Schild A.L., Kommers G.D. & Barros C.S.L. 2008. [Stringhalt in horses from the state of Rio Grande do Sul, Brazil.] Harpejamento em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(1):23-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical, gross and histological findings of cases of stringhalt occurring in horses from eight farms in six counties in the State of Rio Grande do Sul, Brazil from 2000-2005 are reported. At least 10 horses were affected. Ages of affected horses were 1-13 years (average 6.2 years) and 1-2 horses were affected in each farm. Factors that might have influenced the appearance of the disease included dearth of forage due to insufficient rainfall. The presence of the plant Hypochaeris radicata, often implicated as a cause of stringhalt in horses, was observed in the pasture of three out of five evaluated farms and in six of these farms the pasture was poor due to scarse precipitation. Estimated morbidity was 17.3% and lethality was close to zero although two horses were euthanatized for necropsy. Characteristic clinical signs included excessive flexion of the stifle and hock joints, impaired ambulation and bunny hop-type of gait. Clinical disease was graded by number scores from 1-5, higher numbers indicating increasing severity. Three horses were graded as 1, one horse as 2, three horses as 3, one horse as 4 and two horses as 5. Treatment with phenytoin in two horses and with phenytoin and tenectomy in another one did not result in amelioration of the clinical signs. Four out of ten clinical examined horses with stringhalt recovered with no treatment within 2-4 months of clinical disease and four affected horses did not recover even after 9-17 months of clinical disease, when they were lastly examined. Necropsy findings included atrophy of skeletal muscle of the large muscular groups which was confirmed histologically. Histological evaluation of peripheral nerves of one of the euthanatized horses revealed reduction or absence of myelinated fibers. Ultrastructural findings included signs of demyelination, regeneration and remyelination of peripheral nerves.

• Neuropathy toxic neuropathy diseases of horses

Abstract in Portuguese:

ABSTRACT.- Rodrigues A., De La Corte F.D., Graça D.L., Rissi D.R., Schild A.L., Kommers G.D. & Barros C.S.L. 2008. [Stringhalt in horses from the state of Rio Grande do Sul, Brazil.] Harpejamento em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(1):23-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical, gross and histological findings of cases of stringhalt occurring in horses from eight farms in six counties in the State of Rio Grande do Sul, Brazil from 2000-2005 are reported. At least 10 horses were affected. Ages of affected horses were 1-13 years (average 6.2 years) and 1-2 horses were affected in each farm. Factors that might have influenced the appearance of the disease included dearth of forage due to insufficient rainfall. The presence of the plant Hypochaeris radicata, often implicated as a cause of stringhalt in horses, was observed in the pasture of three out of five evaluated farms and in six of these farms the pasture was poor due to scarse precipitation. Estimated morbidity was 17.3% and lethality was close to zero although two horses were euthanatized for necropsy. Characteristic clinical signs included excessive flexion of the stifle and hock joints, impaired ambulation and bunny hop-type of gait. Clinical disease was graded by number scores from 1-5, higher numbers indicating increasing severity. Three horses were graded as 1, one horse as 2, three horses as 3, one horse as 4 and two horses as 5. Treatment with phenytoin in two horses and with phenytoin and tenectomy in another one did not result in amelioration of the clinical signs. Four out of ten clinical examined horses with stringhalt recovered with no treatment within 2-4 months of clinical disease and four affected horses did not recover even after 9-17 months of clinical disease, when they were lastly examined. Necropsy findings included atrophy of skeletal muscle of the large muscular groups which was confirmed histologically. Histological evaluation of peripheral nerves of one of the euthanatized horses revealed reduction or absence of myelinated fibers. Ultrastructural findings included signs of demyelination, regeneration and remyelination of peripheral nerves.

Abstract in English:

ABSTRACT.- Schons S.V., Kommers G.D., Pereira G.M., Raffi M.B. & Schild A.L. 2007. [Microscopic, immunohistochemical, and ultra-structural study of the lesions experimentaly induced by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Estudo histológico, imuno-histoquímico e ultra-estrutural das lesões induzidas experimentalmente por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 27(7):269-276. Laboratório Regional de Diagnóstico, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The objective of this study was to investigate the pathogenesis of the lesions observed in cattle experimentally poisoned by Ramaria flavo-brunnescens. The mushroom was given to three 9 to10-month-old Jersey calves immediately after harvesting. Daily doses were around 20g/kg of body weight during 7 (Calf 1) or 13 days (Calves 2-3), and the total doses of mushroom given were 140, 268, and 261g/kg of body weight, respectively. One calf (Calf 4) with same age and breed was used as control. Clinical signs were characterized by prostration, anorexia, hyperemia of oral mucosa, and loosening of long hairs of the tail tip under mild traction. The calves were submitted to euthanasia and necropsied on days 8 (Calf 1) and 15 (Calves 2-4) after the beginning of the experiment. Microscopically, there was smoothness of dorsal epithelium of tongue with absence of filiform papillae, vacuolation of keratinocytes, and loosening of the keratin layer. In the hooves, there was vacuolation and irregular keratinization of the laminar epidermis and hyperplasia of keratinocytes. Hyperkeratosis, vacuolation of the external root sheath, thickening of tricholemal keratin, and inflammatory infiltration around hair follicles were observed on the skin of the tail tip. Immunohistochemical results with anti-pancytoceratin and anti-Ki67 (cell proliferation marker) antibodies showed no differences between the tongue dorsal epithelium of the control and experimental calves. Ultrastructural study demonstrated decrease in tonofilaments and increased intercellular spaces of the spinous layer of the tongue dorsal epithelium. The results of this study favor the hypothesis of an interference with the epithelial keratinization mechanisms by the toxic principles of Ramaria flavo-brunnescens.

• Ramaria flavo-brunnecens mushroom poisoning cattle diseases pathology

Abstract in Portuguese:

ABSTRACT.- Schons S.V., Kommers G.D., Pereira G.M., Raffi M.B. & Schild A.L. 2007. [Microscopic, immunohistochemical, and ultra-structural study of the lesions experimentaly induced by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Estudo histológico, imuno-histoquímico e ultra-estrutural das lesões induzidas experimentalmente por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 27(7):269-276. Laboratório Regional de Diagnóstico, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The objective of this study was to investigate the pathogenesis of the lesions observed in cattle experimentally poisoned by Ramaria flavo-brunnescens. The mushroom was given to three 9 to10-month-old Jersey calves immediately after harvesting. Daily doses were around 20g/kg of body weight during 7 (Calf 1) or 13 days (Calves 2-3), and the total doses of mushroom given were 140, 268, and 261g/kg of body weight, respectively. One calf (Calf 4) with same age and breed was used as control. Clinical signs were characterized by prostration, anorexia, hyperemia of oral mucosa, and loosening of long hairs of the tail tip under mild traction. The calves were submitted to euthanasia and necropsied on days 8 (Calf 1) and 15 (Calves 2-4) after the beginning of the experiment. Microscopically, there was smoothness of dorsal epithelium of tongue with absence of filiform papillae, vacuolation of keratinocytes, and loosening of the keratin layer. In the hooves, there was vacuolation and irregular keratinization of the laminar epidermis and hyperplasia of keratinocytes. Hyperkeratosis, vacuolation of the external root sheath, thickening of tricholemal keratin, and inflammatory infiltration around hair follicles were observed on the skin of the tail tip. Immunohistochemical results with anti-pancytoceratin and anti-Ki67 (cell proliferation marker) antibodies showed no differences between the tongue dorsal epithelium of the control and experimental calves. Ultrastructural study demonstrated decrease in tonofilaments and increased intercellular spaces of the spinous layer of the tongue dorsal epithelium. The results of this study favor the hypothesis of an interference with the epithelial keratinization mechanisms by the toxic principles of Ramaria flavo-brunnescens.

Abstract in English:

ABSTRACT.- Sant’Ana F.J.F., Garcia E.C., Rabelo R.E., Costa Y.L., Schild A.L. & Riet-Correa F. 2007. [Oropharyngeal and neurologic lesions in sheep associated with the use of drenching guns.] Lesões orofaríngeas e neurológicas em ovinos associadas ao uso de pistolas dosificadoras. Pesquisa Veterinária Brasileira 27(7):282-286. Laboratório de Patologia Veterinária, Universidade Federal de Goiás, Campus Jataí, 75800-000 Jataí, GO, Brazil. E-mail: santanafjf@yahoo.com Six outbreaks of oropharyngeal lesions caused by drenching guns in sheep are reported. In 2 outbreaks in Rio Grande do Sul the morbidity was 6.25% and 15%, and the lesions observed after antihelmintic treatment in adult sheep were characterized by a fistula extending from mouth to skin of the face. All sheep died or were euthanatized after continuous weight loss for up to 8 months. Another outbreak in the same State affected 26 out of 360 adult sheep after being dosed with molasses, causing lesions in the oral mucosa followed by malignant edema of the oral and subcutaneous tissues. All sheep died within 10 days after treatment. Another case observed in Rio Grande do Sul affected one out of 88 adult ewes. The animal died with hemorrhages from the nose and mouth 8 days after antihelmintic treatment. At necropsy an ulcerated lesion covered by a clot of fibrine was found in the oral mucosa. The lesion had a fistulated tract with purulent exudate extending through the soft tissues in direction to the right eye. Two outbreaks occurred in the State of Goiás 16-20 days after antihelmintic treatment in 5-9 months old lambs. Morbidity was 11.43% and 15.62% and fatality rate was 7.14% and 9.38%. Main clinical signs were nervous signs caused by abscesses with a diameter of 0.5-3cm, containing purulent exudates in the oropharynx, soft palate and adjacent muscles extending to the meninges through the atlantoaxial joint. Not-purulent meningitis was observed histologically. The need to use proper drenching guns and pay attention during dosing to avoid lesions of the oropharynx is pointed out.

• Oropharyngeal abscess neurologic alterations drenching guns sheep

Abstract in Portuguese:

ABSTRACT.- Sant’Ana F.J.F., Garcia E.C., Rabelo R.E., Costa Y.L., Schild A.L. & Riet-Correa F. 2007. [Oropharyngeal and neurologic lesions in sheep associated with the use of drenching guns.] Lesões orofaríngeas e neurológicas em ovinos associadas ao uso de pistolas dosificadoras. Pesquisa Veterinária Brasileira 27(7):282-286. Laboratório de Patologia Veterinária, Universidade Federal de Goiás, Campus Jataí, 75800-000 Jataí, GO, Brazil. E-mail: santanafjf@yahoo.com Six outbreaks of oropharyngeal lesions caused by drenching guns in sheep are reported. In 2 outbreaks in Rio Grande do Sul the morbidity was 6.25% and 15%, and the lesions observed after antihelmintic treatment in adult sheep were characterized by a fistula extending from mouth to skin of the face. All sheep died or were euthanatized after continuous weight loss for up to 8 months. Another outbreak in the same State affected 26 out of 360 adult sheep after being dosed with molasses, causing lesions in the oral mucosa followed by malignant edema of the oral and subcutaneous tissues. All sheep died within 10 days after treatment. Another case observed in Rio Grande do Sul affected one out of 88 adult ewes. The animal died with hemorrhages from the nose and mouth 8 days after antihelmintic treatment. At necropsy an ulcerated lesion covered by a clot of fibrine was found in the oral mucosa. The lesion had a fistulated tract with purulent exudate extending through the soft tissues in direction to the right eye. Two outbreaks occurred in the State of Goiás 16-20 days after antihelmintic treatment in 5-9 months old lambs. Morbidity was 11.43% and 15.62% and fatality rate was 7.14% and 9.38%. Main clinical signs were nervous signs caused by abscesses with a diameter of 0.5-3cm, containing purulent exudates in the oropharynx, soft palate and adjacent muscles extending to the meninges through the atlantoaxial joint. Not-purulent meningitis was observed histologically. The need to use proper drenching guns and pay attention during dosing to avoid lesions of the oropharynx is pointed out.

Abstract in English:

ABSTRACT.- Almeida M.B., Tortelli F.P., Riet-Correa B., Ferreira J.L.M., Soares M.P., Farias N.A.R., Riet-Correa F. & Schild A.L. 2006. [Tick fever in southern Brazil: a retrospective study of 1978-2005.] Tristeza parasitária bovina na região sul do Rio Grande do Sul: estudo retrospectivo de 1978-2005. Pesquisa Veterinária Brasileira 26(4):236-242. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br A retrospective study of tick fever was made, which occurred from 1978-2005 in southern Rio Grande do Sul in the influence area of the Regional Diagnostic Laboratory of the Federal University of Pelotas. From 4,884 cattle specimens, sent by practitioners or which were from necropsies performed at the Diagnostic Laboratory, 231 (4.7%) were diagnosed as tick fever. Data from 221 of those outbreaks were analyzed. Ninety one (41.1%) outbreaks were caused by Babesia bovis, 11 (4.9%) by Babesia bigemina, and 65 (29.41%) by Anaplasma marginale. In other 33 (14.93%) outbreaks of babesiosis there is no information if the disease was caused by B. bovis or B. bigemina, and 21 (9.5%) outbreaks were caused by mixed infection of A. marginale and B. bovis or B. bigemina. Mean morbidity, mortality, and letality rates in 149 outbreaks were 11.17%, 6.81%, and 70.04%, respectively. Most outbreaks occurred during summer (January-March) and autumn (April-June), mainly in 1 to 3-year-old cattle. Clinical signs were depression, weakness, fallen ears, fever, and weight loss. Low packed cell volume values were always found. Hemoglobinury was observed in babesiosis. Neurological signs characterized by gait alterations, muscular tremors, aggressiveness and falling down with tonic and clonic convulsions were observed in babesiosis by B. bovis. The main gross lesions were anemia, jaundice, splenomegaly, hepatomegaly, yellow liver and cardiac hemorrhages. Hemoglobinury was observed in babesiosis, and congestion of the cerebral cortex in babesiosis by B. bovis. It is concluded that B. bovis is the main agent causing thick fever in southern Rio Grande do Sul. In that region with a cattle population of 2,630,000 heads the annual losses due to tick fever can be estimated in 6,220 cattle or US$ 1,623,000.00. Preventive measures to diminish tick fever losses in the region are necessary.

• Parasitic diseases tick fever epidemiology Babesia bovis Babesia bigemina Anaplasma marginale

Abstract in Portuguese:

ABSTRACT.- Almeida M.B., Tortelli F.P., Riet-Correa B., Ferreira J.L.M., Soares M.P., Farias N.A.R., Riet-Correa F. & Schild A.L. 2006. [Tick fever in southern Brazil: a retrospective study of 1978-2005.] Tristeza parasitária bovina na região sul do Rio Grande do Sul: estudo retrospectivo de 1978-2005. Pesquisa Veterinária Brasileira 26(4):236-242. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br A retrospective study of tick fever was made, which occurred from 1978-2005 in southern Rio Grande do Sul in the influence area of the Regional Diagnostic Laboratory of the Federal University of Pelotas. From 4,884 cattle specimens, sent by practitioners or which were from necropsies performed at the Diagnostic Laboratory, 231 (4.7%) were diagnosed as tick fever. Data from 221 of those outbreaks were analyzed. Ninety one (41.1%) outbreaks were caused by Babesia bovis, 11 (4.9%) by Babesia bigemina, and 65 (29.41%) by Anaplasma marginale. In other 33 (14.93%) outbreaks of babesiosis there is no information if the disease was caused by B. bovis or B. bigemina, and 21 (9.5%) outbreaks were caused by mixed infection of A. marginale and B. bovis or B. bigemina. Mean morbidity, mortality, and letality rates in 149 outbreaks were 11.17%, 6.81%, and 70.04%, respectively. Most outbreaks occurred during summer (January-March) and autumn (April-June), mainly in 1 to 3-year-old cattle. Clinical signs were depression, weakness, fallen ears, fever, and weight loss. Low packed cell volume values were always found. Hemoglobinury was observed in babesiosis. Neurological signs characterized by gait alterations, muscular tremors, aggressiveness and falling down with tonic and clonic convulsions were observed in babesiosis by B. bovis. The main gross lesions were anemia, jaundice, splenomegaly, hepatomegaly, yellow liver and cardiac hemorrhages. Hemoglobinury was observed in babesiosis, and congestion of the cerebral cortex in babesiosis by B. bovis. It is concluded that B. bovis is the main agent causing thick fever in southern Rio Grande do Sul. In that region with a cattle population of 2,630,000 heads the annual losses due to tick fever can be estimated in 6,220 cattle or US$ 1,623,000.00. Preventive measures to diminish tick fever losses in the region are necessary.

Abstract in English:

ABSTRACT.- Schild A.L., Sallis E.S.V., Priebe A.P., Soares M.P., Almeida M.B., Ladeira S.R.L., Schramm R. & Riet-Correa F. 2006. Anthrax in cattle in southern Brazil: 1978-2006. Pesquisa Veterinária Brasileira 26(4):243-248. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Univer-sidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br Ten outbreaks of anthrax occurred in cattle from 1978 to 2006 in southern Brazil, in 5 municipalities on the border with Uruguay, a country where the disease is frequent. The 10 outbreaks represented 0.2% of all bovine specimens received during the period by the Regional Diagnostic Laboratory of the Federal University of Pelotas, causing 267 deaths in a risk population of 6,605 head. The disease affected young and adult cattle mainly during summer. Only one farmer reported that sheep and horses were also affected. Clinically the peracute form was more frequent, but in some outbreaks the acute form with a clinical manifestation period of 6-48 hours was also observed. The source of infection was not established; but the reduced rainfall, associated with low, flat, flooded lands used for agriculture followed by animal grazing after harvest was probably related to the disease occurrence. Annual vaccination is an efficient way to prevent the disease.

• Anthrax Bacillus anthracis infectious disease disease of cattle

Abstract in Portuguese:

ABSTRACT.- Schild A.L., Sallis E.S.V., Priebe A.P., Soares M.P., Almeida M.B., Ladeira S.R.L., Schramm R. & Riet-Correa F. 2006. Anthrax in cattle in southern Brazil: 1978-2006. Pesquisa Veterinária Brasileira 26(4):243-248. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Univer-sidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br Ten outbreaks of anthrax occurred in cattle from 1978 to 2006 in southern Brazil, in 5 municipalities on the border with Uruguay, a country where the disease is frequent. The 10 outbreaks represented 0.2% of all bovine specimens received during the period by the Regional Diagnostic Laboratory of the Federal University of Pelotas, causing 267 deaths in a risk population of 6,605 head. The disease affected young and adult cattle mainly during summer. Only one farmer reported that sheep and horses were also affected. Clinically the peracute form was more frequent, but in some outbreaks the acute form with a clinical manifestation period of 6-48 hours was also observed. The source of infection was not established; but the reduced rainfall, associated with low, flat, flooded lands used for agriculture followed by animal grazing after harvest was probably related to the disease occurrence. Annual vaccination is an efficient way to prevent the disease.

Abstract in English:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

• Status spongiosus astrocytic edema congenital diseases cattle

Abstract in Portuguese:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

Abstract in English:

ABSTRACT.- Moreira Souto M.A., Kommers G.D., Barros C.S.L., Piazer J.V.M., Rech R.R., Riet-Correa F. & Schild A.L. 2006. [Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum).] Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum). Pesquisa Veterinária Brasileira 26(2):112-122. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com Thirty bovine with neoplasms of the upper digestive tract (UDT) associated with spontaneous ingestion of bracken fern (Pteridium aquilinum) were studied. They were from 27 farms, located in the municipalities of Jaguari (23) and Nova Esperança do Sul (4), Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%). Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage of disease and necropsied. The main gross and microscopic alterations were found in identical areas of the UDT. They consisted of papillomas, transforming papillomas, and squamous cell carcinomas (SCCs). Metastases of SCCs to regional lymph nodes and other organs, such as liver and lungs, were also observed (18/30). Twenty-nine bovine had papillomas of various sizes in several areas of the UDT. The digestive papillomatosis ranged from mild (45%), to moderate (38%), to severe (17%). Three developing phases were observed microscopically in the examined papillomas: an early growing phase, a developing phase, and a regressing phase. In 16 cases, there was malignant transformation of papillomas into SCCs. The SCCs were solitary (12/30) or multiple (18/30) and were histologically well, moderately, or poorly differentiated. Grouping the distribution of SCCs of larger extension in the UDT into cranial region (base of the tongue, pharynx/oropharynx, and epiglottis), medial region (esophagus), and caudal region (cardia and rumen), the distribution was cranial in 39%, middle in 16%, and caudal in 45% of the cases. By the same grouping criteria, but considering the total number of times SCCs of varied extensions were diagnosed in the cranial, middle, and caudal regions, the percentages changed to 34%, 26%, and 40%, respectively. The epidemiological and histomorphological evidences found in this study are in agreement with the observations that point out the co-carcinogenesis between bovine papillomavirus type 4 infection and chemicals of bracken fern in the pathogenesis of the SCCs in the UDT of cattle. However, the presence of pre-neoplastic changes and SCCs in situ or in early stages of development, independently of the presence of papillomas, clearly indicates the possibility of development of SCCs from normal epithelium, probably due to the direct action of the chemical carcinogens contained in bracken fern.

• Poisonous plants Pteridium aquilinum plant poisoning bovine papillomavirus type 4 squamous cell carcinoma diseases of cattle pathology.

Abstract in Portuguese:

ABSTRACT.- Moreira Souto M.A., Kommers G.D., Barros C.S.L., Piazer J.V.M., Rech R.R., Riet-Correa F. & Schild A.L. 2006. [Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum).] Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum). Pesquisa Veterinária Brasileira 26(2):112-122. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com Thirty bovine with neoplasms of the upper digestive tract (UDT) associated with spontaneous ingestion of bracken fern (Pteridium aquilinum) were studied. They were from 27 farms, located in the municipalities of Jaguari (23) and Nova Esperança do Sul (4), Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%). Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage of disease and necropsied. The main gross and microscopic alterations were found in identical areas of the UDT. They consisted of papillomas, transforming papillomas, and squamous cell carcinomas (SCCs). Metastases of SCCs to regional lymph nodes and other organs, such as liver and lungs, were also observed (18/30). Twenty-nine bovine had papillomas of various sizes in several areas of the UDT. The digestive papillomatosis ranged from mild (45%), to moderate (38%), to severe (17%). Three developing phases were observed microscopically in the examined papillomas: an early growing phase, a developing phase, and a regressing phase. In 16 cases, there was malignant transformation of papillomas into SCCs. The SCCs were solitary (12/30) or multiple (18/30) and were histologically well, moderately, or poorly differentiated. Grouping the distribution of SCCs of larger extension in the UDT into cranial region (base of the tongue, pharynx/oropharynx, and epiglottis), medial region (esophagus), and caudal region (cardia and rumen), the distribution was cranial in 39%, middle in 16%, and caudal in 45% of the cases. By the same grouping criteria, but considering the total number of times SCCs of varied extensions were diagnosed in the cranial, middle, and caudal regions, the percentages changed to 34%, 26%, and 40%, respectively. The epidemiological and histomorphological evidences found in this study are in agreement with the observations that point out the co-carcinogenesis between bovine papillomavirus type 4 infection and chemicals of bracken fern in the pathogenesis of the SCCs in the UDT of cattle. However, the presence of pre-neoplastic changes and SCCs in situ or in early stages of development, independently of the presence of papillomas, clearly indicates the possibility of development of SCCs from normal epithelium, probably due to the direct action of the chemical carcinogens contained in bracken fern.