Plasma IGF-I and lactoferrin as biomarkers of post-weaning stress and the effect of feeding probiotic to low body weight calves for the improvement of growth performance in crossbred KF calves

Abstract

Management practices as well as environmental and pathological stresses have an impact on growth performances and health status of calves. Lactoferrin is a glycoprotein and is a prominent component of host-defense against infection. Insulin like growth factor I (IGF-I) has been established as a biochemical indicator for different production traits. The present study was under taken to evaluate the role of IGF-I and lactoferrin as biomarkers for growth performances and health status in female crossbred KF calves and the effect of probiotic (Saccharomyces cerevisiae) supplementation on growth performance in post-weaned calves. Plasma concentration of these factors were correlated with growth performances in terms of body weight gain, dry matter intake, feed conversion efficiency, metabolic body weight gain in post-weaned calves. Calves exhibiting normal body weight (HBW) and the ones exhibiting lesser body weight (LBW) with respect to age (P<0.01) were divided into 2 groups. The body weight of LBW group was significantly less (P<0.001) during the pre-supplementation period (122 days). At 60d post-supplementation period, the significant difference between the body weight decreased (P<0.01). The circulatory level of IGF-I was significantly high (P<0.01) in HBW group when compared with LBW. During the post-supplementation period, the concentration of lactoferrin was not significantly different in both the groups and had decreased to the basal level (500–420 vs.150–250ng/ml) in comparison to pre-supplementation period, suggesting normal immune status and reduced stress/ inflammation. Supplementation of probiotic improved growth performance to a lesser extent in LBW group. IGF-I can act as a marker for growth performance in crossbred calves.