Abstract :
In this study 71 head of conceiving ewe and their progeny (91 head) from the flock of Lori-Bakhtiari sheep (360 head), in Sholi Station were randomly selected to determine the relationship between the immu-noglobulin (IgG) concentration in the eweʹs serum and colostrum, and lambʹs serum. Ewe blood sample, colostrum of ewe and blood of the lamb was taken 2 weeks before parturition, 1 to 8 hours after parturition and 36 hours after birth of lamb, respectively. The serum of samples was extracted and then IgG (mg/mL) was measured in samples based on single radial immunodiffusion test and total serum protein (gr/L) based on quantitative zinc sulfate turbidity method. Results showed that the overall mean of IgG were 21.33, 48.48 and 7.86 mg/mL for blood serum of ewe, serum colostrum of ewe and blood serum of the lamb and total serum protein were 71.98, 114.48 and 65.77 g/L, respectively. The effects of age of ewe, type of partu-rition, gender of lamb, body condition score and body weight of ewe on considered immunity traits were not significant (P > 0.05). The correlation coefficients between IgG in serum of blood and serum of colos-trum in ewe and serum of blood in lamb were medium to high (0.35 to 0.75) and significant (P < 0.05). The regression coefficients of IgG concentration in lambʹs serum on values in eweʹs serum at 2 weeks before parturition was highly significant (P < 0.01) and shows that IgG content in lambʹs serum increase by 0.18 units per increasing one unit in IgG content in eweʹs serum. Therefore, the level of IgG in lambʹs serum could be affected by the IgG concentrations in ewe’s serum and colostrum. Also, the level of IgG in lambʹs serum could be enhanced by improving the level of IgG concentration in eweʹs serum at two weeks before lambing.
