PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Hypotrichosis congenita is a significant disease in Hereford cattle in Uruguay and has been reported worldwide. However, the causal mutation KRT71 has only been recently identified. This communication describes the clinical, histopathological, trichographic, and genetic findings of KRT71-hypotrichosis congenita observed in Hereford calves from two commercial farms. Five affected newborn calves, born in a herd of 15 purebred Polled HF cows, were examined in Farm 1, and one weaned calf in Farm 2. Skin biopsies for histopathology, hair samples for trichogram, and blood samples for genotyping were obtained from affected and control calves and the sire bull and mother cows. Affected animals exhibited a light brown coat with sparse, thin, curly or woolly haircoat. Hypotrichotic skin was dry, erythematous, and scaly. Trichogram analysis revealed thin, fragmented, curly hairs with irregular macro-melanosome groups. The main histopathological findings included marked follicular dysplasia with vacuolation, abnormally large trichohyaline granules in Huxley’s layer, and multiple melanin aggregates in hair fragments, matrix cells, and dysplastic follicles. There were no histological lesions of dermatitis. DNA analysis confirmed that hypotrichotic calves were homozygous for the KRT71 mutation, while one control calf, the bull, and cows in Farm 2 were heterozygous carriers. In conclusion, hypotrichosis congenita in Hereford cattle due to the KRT71 mutation is a color dilution follicular dysplasia.

• Hypotrichosis congenita coat-color dilution Hereford cattle semi-hairlessness KRT71 mutation

Abstract in Portuguese:

A hipotricose congênita é uma doença significativa em bovinos Hereford no Uruguai e tem sido relatada em todo o mundo. No entanto, a mutação causal KRT71 foi identificada apenas recentemente. Esta comunicação descreve os achados clínicos, histopatológicos, tricográficos e genéticos da KRT71-hipotricose congênita observada em bezerros Hereford de duas fazendas comerciais diferentes. Cinco bezerros recém-nascidos afetados, nascidos em um rebanho de 15 vacas puras Polled HF, foram examinados na Fazenda 1, e um bezerro desmamado na Fazenda 2. Biópsias de pele para histopatologia, amostras de pelo para tricograma e amostras de sangue para genotipagem foram obtidas de bezerros afetados e controle, bem como do touro e das vacas. Animais afetados apresentaram uma pelagem marrom clara com pelos esparsos, finos, crespos ou lanosos. A pele hipotricótica era seca, eritematosa e escamosa. A análise do tricograma revelou pelos finos, fragmentados e crespos, com grupos irregulares de macro-melanossomas. Os principais achados histopatológicos incluíram displasia folicular acentuada com vacuolização e grânulos tricohialinos anormalmente grandes na camada de Huxley e múltiplos agregados de melanina em fragmentos de cabelo, células da matriz e folículos displásicos. Não foram observadas lesões histológicas de dermatite. A análise de DNA confirmou que os bezerros hipotricóticos eram homozigotos para a mutação KRT71, enquanto um bezerro controle, o touro e as vacas da Fazenda 2 eram portadores heterozigotos. Em conclusão, a hipotricose congênita em bovinos Hereford devido à mutação KRT71 é uma displasia folicular de diluição de cor.

• Hipotricose congênita diluição de cor da pelagem gado Hereford semipelagem mutação KRT71

Abstract in English:

ABSTRACT.- Mancini M., Rodriguez C., Prosperi C., Salinas V. & Bucco C. 2006. Main diseases of pejerrey (Odontesthes bonariensis) in central Argentina. Pesquisa Veterinária Brasileira 26(4):205-210. Facultad de Agronomía y Veterinaria. Universidad Nacional de Río Cuarto, Ruta Nac. 36 Km 601, Río Cuarto (5800) Córdoba, Argentina. E-mail: mmancini@ayv.unrc.edu.ar Argentina’s central region includes an important area covered by shallow pampean lakes and dams. In these environments, fishing of pejerrey Odontesthes bonariensis Valenciennes, 1835 (Pisces, Atherinopsidae), the most important fresh-water fish of the country, is a relevant social activity and also a considerable economic resource. The main diseases found in this species were studied from 1992 to 2003 in the provinces of Córdoba, La Rioja and Santa Fe (30° and 35° S, 61° and 67° W). Most cases were registered in high temperature months. Lernaea sp and Aeromonas hydrophila were the etiological agents most frequently found. The trophic characteristics of the aquatic environments enhanced disease processes and caused massive death of O. bonariensis, due to complex hydrochemical interactions.

• Odontesthes bonariensis fish diseases pathological agents water quality

Abstract in Portuguese:

ABSTRACT.- Mancini M., Rodriguez C., Prosperi C., Salinas V. & Bucco C. 2006. Main diseases of pejerrey (Odontesthes bonariensis) in central Argentina. Pesquisa Veterinária Brasileira 26(4):205-210. Facultad de Agronomía y Veterinaria. Universidad Nacional de Río Cuarto, Ruta Nac. 36 Km 601, Río Cuarto (5800) Córdoba, Argentina. E-mail: mmancini@ayv.unrc.edu.ar Argentina’s central region includes an important area covered by shallow pampean lakes and dams. In these environments, fishing of pejerrey Odontesthes bonariensis Valenciennes, 1835 (Pisces, Atherinopsidae), the most important fresh-water fish of the country, is a relevant social activity and also a considerable economic resource. The main diseases found in this species were studied from 1992 to 2003 in the provinces of Córdoba, La Rioja and Santa Fe (30° and 35° S, 61° and 67° W). Most cases were registered in high temperature months. Lernaea sp and Aeromonas hydrophila were the etiological agents most frequently found. The trophic characteristics of the aquatic environments enhanced disease processes and caused massive death of O. bonariensis, due to complex hydrochemical interactions.