RELATIONSHIP OF RESIDUAL FEED INTAKE WITH BLOOD METABOLITES AND HORMONES IN SAHIWAL FEMALE CALVES
KULDEEP DUDI* AND CHANDER DATT
Livestock Research Centre,
(Reveived: 21 April 2015; Accepted: 1June 2015)
The study was conducted to find relationship of residual feed intake (feed efficiency parameter) with various blood metabolites in growing Sahiwal female calves. Healthy Sahiwal female calves (n=18) were selected and fed total mixed rations consisting of wheat straw, berseem (Trifolium alexandrinum) and concentrate mixture (mesh, BIS type-I) according to their body requirements. Net feed intake and body weights were recorded at regular intervals. Residual feed intake (RFI) values were calculated for individual calves and they were designated low RFI group with negative (n= 9; RFI= -0.14 kg/ d) and high RFI group with positive (n= 9; RFI= +0.14 kg/d) RFI values. Low RFI consumed less (P<0.05) dietary DM compared to high RFI group (2.56 vs 3.02kg/100 kg B.wt.) while gaining similar body weights (0.48 and 0.47 kg/d) indicating higher efficiency of feed utilisation in the former group. Low RFI group showed better feed conversion ratio (20.29% lower), compared to high RFI group (5.52 and 6.64 kg DM consumed/kg gain). The values of blood glucose (56.71 and 59.14 mg/dl); total plasma protein (7.32 and 7.54 g/dl) and growth hormone (4.37 and 4.29 ng/ml) were similar in both groups. Low RFI group possessed higher (P<0.05) values for creatinine (1.52 vs 1.26 mg/dl) and IGF-1 (140.40 vs 122.49 ng/ml). On the contrary, the levels of aspartate aminotransferase (118.74 vs 97.51 IU/L) and BUN (22.03 vs 18.14 mg/dl) were higher in high RFI group compared to low RFI group.
Key words:RFI, Residual feed intake, blood biomarkers, feed efficiency