Evaluation of data from mitogen studies in CBA mice: comparison of counts per minute, stimulation index and relative proliferation index.

Lymphocyte proliferation assays were conducted on splenic lymphocytes collected from CBA mice that had been exposed to lead acetate or cadmium chloride for 10 weeks. The ability of mitogens concanavalin A and lipopolysaccharide, as well as purified protein derivative, to induce proliferation in vitro in the presence or absence of macrophages was assessed. Data were compared by using counts per minute (cpm), stimulation index, and relative proliferative index. Data varied considerably within treatment groups performed on different days, which is a typical characteristic of mitogen proliferation investigations. According to cpm data, only 3 of 21 treatments were significantly (P less than 0.05) altered when compared with controls. The stimulation indices were highly influenced by background counts and frequently did not correlate with cpm. The relative proliferative index, on the other hand, calculates net cpm, closely corresponds to cpm, compensates for background counts and is affected less by variation than is the stimulation index, and selected cutoff values give a more sensitive measure for determination of altered proliferative responses when statistical procedures are not applicable. Effects of macrophages, carbon dioxide, and bovine fetal serum on lymphocyte transformation are discussed.     

Carcase Composition of Taiwan Simulated Native Chickens

This study investigated the carcase composition of Taiwan simulated native chickens at different stages of growth. The results indicated that the carcases of male chickens exhibited significantly larger protein mass and water mass than those of females during weeks 7 to 20; as was the ash mass during weeks 8 to 20. However, the fat mass of the carcases of female chickens was larger than that of males during weeks 14 to 20. Separate regression equations were derived for the relationship between protein mass, fat mass, ash mass and water mass and both carcase weight and age of both male and female chickens.