Siena Giulia, di Nardo Francesca, Contiero Barbara, Milani Chiara
Department of Animal Medicine, Production and Health, University of Padova, Via dell'Università, 16, Legnaro, PD, 35020, Italy.
Vet Res Commun. 2023 Sep;47(3):1653-1663. doi: 10.1007/s11259-023-10120-2. Epub 2023 Apr 24.
Data concerning the use of the canine foetal kidney length (L) formula in the prediction of parturition timing are still lacking. In our study, we aimed to evaluate the accuracy of the L formula in predicting the parturition date during the last 10 days of pregnancy. Twenty-five clinically healthy pregnant bitches, aged 2-9 years and weighing 3.5-52.2 kg, were ultrasonographically monitored from -11 to 0 days before parturition (dbp). Kidney L was measured for the three most caudal foetuses, and the parturition day was estimated using the kidney formula, whose accuracy was calculated as the percentage of cases estimated (ranges of ± 1 or ± 2 days) on the actual parturition date. A K-proportions test was performed to identify differences in the accuracy among maternal sizes and the sex ratio of pups, and a two-proportions z-test was performed to identify differences between litter size classes (≤ 7 vs. > 7 pups) and time ranges (-11/-5 and -4/0 dbp). An accuracy of 35% within ± 2 days was found in the range of -11/-5 dbp and an accuracy of 30% within ± 2 days was found in the range of -4/0 dbp. The accuracy differed between small (53% ±1 day and 60% ±2 days) and large (10% within ± 1 and ± 2 days) bitches (P = 0.019 within ± 1 day, and P = 0.007 within ± 2 days). For small litter sizes, the accuracy was 38% within ± 1 day and 44% within ± 2 days, and for large litter sizes, it was 14% within ± 1 and ± 2 days. A threshold value was found between litter size classes within ± 2 days. The use of the L formula during the last ten days of pregnancy did not seem to warrant good accuracy in the prediction of parturition date. Further studies on different maternal sizes should be performed.
关于犬胎儿肾长（L）公式在预测分娩时间方面的应用数据仍然匮乏。在我们的研究中，我们旨在评估L公式在预测妊娠最后10天分娩日期时的准确性。对25只临床健康的怀孕母犬进行了超声监测，这些母犬年龄在2至9岁之间，体重在3.5至52.2千克之间，监测时间为分娩前（dbp）的-11天至0天。测量了最尾端的三只胎儿的肾长，并使用肾长公式估计分娩日期，其准确性通过估计日期（±1天或±2天范围）与实际分娩日期相符的病例百分比来计算。进行了K比例检验以确定母体大小和幼犬性别比例之间准确性的差异，并进行了双比例z检验以确定窝仔数类别（≤7只与>7只幼犬）和时间范围（-11/-5和-4/0 dbp）之间的差异。在-11/-5 dbp范围内，±2天内的准确性为35%，在-4/0 dbp范围内，±2天内的准确性为30%。小型（±1天内为53%，±2天内为60%）和大型（±1天和±2天内均为10%）母犬之间的准确性存在差异（±1天内P = 0.019，±2天内P = 0.007）。对于小窝仔数，±1天内的准确性为38%，±2天内为44%，对于大窝仔数，±1天和±2天内均为14%。在±2天内发现了窝仔数类别之间的阈值。在妊娠最后十天使用L公式似乎无法保证在预测分娩日期方面有良好的准确性。应针对不同母体大小开展进一步研究。
