Procedures for measuring length of the pig uterus

A method for measuring uterine length in pigs was standardized following a series of experiments to determine the effect of period of storage, temperature, presence of ligaments and the nature of the surrounding fluid on the length of the uterus. Weight of the uterus did not change during storage. Measurements in vivo were compared with those in vitro. The uterus shortened immediately after its removal, then gradually lengthened over 8 h. Whereas there was change in absolute measured length during the storage period, the relationship of length in vivo was significantly correlated to length in vitro (r = .85, P less than .001). Measurement at one time during storage was highly correlated with measurement at other times (r = .93 to .96). The coefficient of variation for length of uteri among gilts was 30%. Measurement of length of the uterus must be done under uniform conditions of storage to give meaningful results.