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Hematologic values of thoroughbred foals from birth to six months of age

Valores hematológicos de potros puro sangue inglês do nascimento aos seis meses de idade


The common domestic equine species present various hematological differences within reference values as a result of age, breed, sex, physical activity, among others. Therefore, it is important that reference intervals should be established for these particularities. This work aimed to evaluate sequential changes in hematological parameters of healthy Thoroughbred foals from birth to six months of life. Blood samples were collected immediately after birth (before the intake of colostrum), at 24 h, 7 days, 1, 2, 3, 4, 5 and 6 months of age in order to measure packed cell volume (PCV), total plasma protein (TPP), fibrinogen and white blood cells (WBC). Descriptive statistics, analysis of one-way AOV and comparison between means by LSD test were accomplished. Hematological values were assessed in 1426 samples. The curve variations in PCV, total plasma protein, fibrinogen and WBC values observed in healthy Thoroughbred foals from birth to 6 months were similar to those described for other breeds. However, we verified higher TPP values than mean reference values at all ages. The ranges of fibrinogen and WBC showed small intervals and maximum values below the hematologic reference values for all ages. These changes in hematologic values provide useful information for clinical evaluation of Thoroughbred foals.

equine neonatal; fibrinogen; hematologic profile; total plasma protein

As espécies domésticas de equídeos apresentam diferença nos valores hematológicos de referencia devido à idade, raça, sexo, atividade física, entre outros.Tendo em vista estas particularidades, é importante o estabelecimento de parâmetros de referência. O objetivo deste trabalhado foi avaliar as mudanças sequenciais de parâmetros hematológicos de potros Puro Sangue Inglês, saudáveis, do nascimento aos seis meses de vida. Amostras sanguineas foram coletadas imediatamente após o parto (antes da ingestão de colostro), as 24h, 7 dias, 1, 2, 3, 4, 5 e 6 meses de idade para mensuração de hematócrito, proteínas plasmáticas totais (PPT), fibrinogênio e leucócitos totais. Foi realizada estatística descritiva, análise de variância simples (teste One-way AOV) e comparação entre as médias pelo teste de LSD. A avaliação hematológica foi realizada em 1426 amostras. A curva de variação do hematócrito, PPT, fibrinogênio e leucócitos totais observada nos potros do nascimento aos 6 meses de idade foram similares às descritas para outras raças. No entanto, valores médios de PPT foram mais elevados durante todo o período. As médias de fibrinogênio e leucócitos apresentaram pequenos intervalos e máximos valores abaixo dos valores de referencia em todos os momentos. As alterações em valores hematológicos têm importância na avaliação clínica de potros Puro Sangue Inglês.

fibrinogênio; neonatologia equina; perfil hematológico; proteína plasmática total

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Publication Dates

  • Publication in this collection
    15 Oct 2014
  • Date of issue
    Sept 2014


  • Received
    30 Apr 2013
  • Accepted
    06 June 2014
Universidade Federal de Goiás Universidade Federal de Goiás, Escola de Veterinária e Zootecnia, Campus II, Caixa Postal 131, CEP: 74001-970, Tel.: (55 62) 3521-1568, Fax: (55 62) 3521-1566 - Goiânia - GO - Brazil