Beccaglia M, Luvoni G C
Department of Veterinary Clinical Sciences-Obstetrics and Gynaecology, University of Milan, Via Celoria 10, 20133 Milan, Italy.
J Small Anim Pract. 2006 Nov;47(11):670-3. doi: 10.1111/j.1748-5827.2006.00108.x.
To compare the accuracy of two ultrasonographic measurements, inner chorionic cavity diameter and biparietal diameter, for the prediction of parturition date in small and medium size bitches. The effects of litter size and fetal sex ratio on the accuracy of the prediction were also investigated.
Ultrasonographic examinations were performed on pregnant bitches and, depending on the stage of pregnancy, the inner chorionic cavity diameter and biparietal diameter were measured. The mean value of the data of each structure was calculated and the predicted day of parturition was obtained by the application of equations derived from growth curves we previously developed for different size bitches.
The parturition term was predicted with similar accuracy during early gestation, by the measurement of inner chorionic cavity diameter, as well as during late gestation, by the measurement of biparietal diameter. Litter size affected only biparietal diameter accuracy, whereas fetal sex ratio did not influence the estimation of the day of parturition.
Inner chorionic cavity diameter and biparietal diameter were equally reliable parameters in obtaining a reasonably accurate prediction of parturition date at any gestational period at which a bitch is examined.
比较两种超声测量方法（绒毛膜内腔直径和双顶径）预测中小型母犬分娩日期的准确性。还研究了窝产仔数和胎儿性别比例对预测准确性的影响。
对怀孕母犬进行超声检查，并根据怀孕阶段测量绒毛膜内腔直径和双顶径。计算每个结构数据的平均值，并通过应用我们之前为不同体型母犬绘制的生长曲线得出的方程来获得预测分娩日期。
在妊娠早期，通过测量绒毛膜内腔直径预测分娩期的准确性与妊娠晚期通过测量双顶径的准确性相似。窝产仔数仅影响双顶径测量的准确性，而胎儿性别比例不影响分娩日期的估计。
在检查母犬的任何妊娠期，绒毛膜内腔直径和双顶径都是获得合理准确分娩日期预测的同样可靠的参数。
