Blood and Colostrum/Milk Serum γ‐Glutamyltransferase Activity as a Predictor of Passive Transfer Status in Lambs

Abstract

The importance of blood and colostrum/milk serum gamma-glutamyl transferase (gamma-GT) enzyme activity was evaluated to assess passive transfer status in healthy lambs. Thirty Akkaraman sheep (3-6 years old) were used which had normal pregnancy period and the same conditions, and the age of the lambs ranged between 0 and 15 days. Blood and colostrum/milk samples were collected from sheep and lambs after birth, before suckling (0) and after on 1st, 3rd, 7th and 15th days. Serum immunoglobulin G (IgG) concentration was determined by the use of Single Radial Immunodiffusion method. Serum gamma-GT activity was measured, using a commercially available kit in blood and colostrum/milk samples. Correlations were carried out between immunoglobulin and gamma-GT levels. Regression models (simple and multiple) were calculated with significant data. Linear correlation was determined between colostrum/milk gamma-GT activity and IgG concentrations and between serum gamma-GT activity and IgG concentrations in lambs on the 0 day. (r: 0.607, P: 0.001), 1st (r: 0.768, P: 0.001) and the 3rd (r: 0.603, P: 0.001) days and on the 1st (r: 0.637, P: 0.001) and 3rd (r: 0.478, P: 0.012) days in the experiment, respectively. Multivariate regression models were developed to estimate sample IgG concentration. Serum and colostrum/milk IgG concentration could be predicted using the formula: lamb serum IgG = 825 + 0.688 (lamb gamma-GT) + 52 (days); colostrum/milk IgG = 832 + 0.505 (colostrum/milk gamma-GT) - 167 (days). The regression models were moderately accurate in predicting serum IgG concentration (R2 = 0.51) and colostrum/milk IgG concentration (R2 = 0.55). Test sensitivity and positive predictive values for serum gamma-GT enzyme activity were found to be 96 and 100% and for colostrum/milk gamma-GT enzyme activity were found to be 100 and 68% to prediction IgG concentration. Serum and colostrum/milk gamma-GT activity can be used to assess passive transfer status of lambs. Along with this, regression models used to calculate serum and colostrum/milk gamma-GT activities found to be useful to estimate sample IgG concentration. The use of serum and colostrum/milk gamma-GT enzyme activity was found useful especially after birth on the 0, 1st and 3rd days.

Risk Factors Associated with Passive Immunity, Health, Birth Weight and Growth Performance in Lambs: II. Effects of Passive Immunity and Some Risk Factors on Growth Performance During the First 12 Weeks of Life

“…Therefore, immunity during the neonatal period depends on the passive transfer of maternal IgG through the colostrum. This process is referred as passive transfer of immunity (PTI), determined by measuring serum IgG concentration (SIgGC) [10][11][12][13] . If neonatal lambs are unable to obtain and absorb a sufficient amount and quality of colostral IgG in the first 12 h of birth, secondary immunodeficiency disorder in other words Failure of Passive Transfer (FPT) develops.…”

Período de absorção intestinal de macromoléculas em cabritos recém-nascidos após a ingestão de colostro bovino

“…A eϐicácia da utilização da atividade da GGT como mé-todo auxiliar para diagnóstico de falha de transferência de imunidade passiva já foi comprovada por outros autores na espécie bovina (Perino et al 1993, caprina (Silva et al 2007) e ovina (Maden et al 2003, Britti et al 2005.…”

“…Na literatura nacional e internacional existem trabalhos que demonstraram correlação positiva entre a atividade da GGT e os valores de imunoglobulina G no soro de ovinos (Maden et al 2003, Britti et al 2005, de bovinos (Perino et al 1993, Fagliari et al 1996, búfalos (Lombardi et al 2001) e caprinos (Silva et al 2007).…”

Avaliação da transferência de imunidade passiva em cordeiros com até 30 dias de idade

“…Muitos são os métodos utilizados para se determinar as concentrações séricas de imunoglobulinas em animais neonatos, e dentre estes, inclui-se a quantificação direta de imunoglobulina G (IgG) por imunodifusão radial 5 . Os valores limítrofes entre hipogamaglobulinemia e concentrações normais de IgG em cordeiros ainda não foram completamente definidos.…”

“…A mensuração da proteína total (PT) no soro sanguíneo pode ser utilizada como método de avaliação indireta de IgG, associando-a à concentração total de globulinas 5 , sendo o seu valor, antes da ingestão de colostro, ao redor de 6,6 g/dL, e de 8,8 g/ dL, após a ingestão ter ocorrido 7 , decrescendo para 7,6 g/dL, às 48 h de vida 8 .…”