Specific Pathogen Free physiological development of inbred mouse strain BALB/cA and C57BL/6J in Specific Pathogen Free System

The study on growth rate and some data involving in the growth of Specific Pathogen Free (SPF) BALB/cA and C57BL/6J inbred mouse strains maintained at National Laboratory Animal Centre, Mahidol University were conducted. The aims wanted to set up data base provide all researcher who used these animals in their works. Body weight was recorded daily from Day 0 to Day 84. The average body weight at birth of males and females from both strains were no significantly differences. The average birth weights of males and females of BALB/cA were 1.93 +/- 0.5 and 1.73 +/- 0.37 gram, respectively. Male body weight was slightly greater than those of female but there were not significantly different (P < 0.05). The average birth weights of males and females of C57BU6J were 1.77 +/- 0.45 and 1.70 +/- 0.35 gram, respectively and were not significantly different (P < 0.01).The majority age of eye opening was day 14 in BALB/cA and day 16 in C57BL/6J. No differences of weight between sex before 6 weeks but there were significantly different (P < 0.05) after 6 weeks old in BAL B/cA whereas C57BL/6J shown no differences of weight between sex before 5 weeks but there were significantly different (P < 0.01) after 5 weeks old.