Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, via dell'Università, 6 - 26900 Lodi, Italy.
Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, via dell'Università, 6 - 26900 Lodi, Italy.
Anim Reprod Sci. 2023 Jan;248:107184. doi: 10.1016/j.anireprosci.2022.107184. Epub 2022 Dec 28.
The definition of new reliable markers for neonatal maturity evaluation is crucial in canine clinical practice. Concerns about the safety of amniotic sampling in pregnant dogs have prevented its collection for diagnostic purposes. Moreover, amniotic fluid had been considered waste material until the latest studies reported amniocentesis as a reliable and safe procedure, even in the canine species. In our study, amniotic fluid (n = 63) collected at birth from ten dogs undergoing elective Caesarean sections at term was analysed to discover new potential indices of canine neonatal maturity. Based on gestational age, mothers and puppies were divided into two groups: the early group (≤65 days from luteinizing hormone (LH) surge, n = 5) and the late group (>65 days from LH surge, n = 5). Amniotic parameters of the lightest and heaviest puppy in individual/each litter, with a birth weight difference of at least 20% among littermates, were also compared. In particular, the content of lecithin, sphingomyelin, surfactant protein A (SP-A), cortisol, and pentraxin 3 (PTX3) in amniotic fluid, which is considered predictive of foetal development in humans, were investigated. Maternal serum SP-A and cortisol were also measured simultaneously. All amniotic parameters were detectable in canine amniotic fluid. Interestingly, the concentrations of different amniotic parameters correlated with each other. Lecithin was positively correlated with sphingomyelin (p < 0.0001), maternal SP-A (p < 0.0005), and the ratio of amniotic and maternal cortisol (p < 0.004). Amniotic SP-A was inversely correlated to maternal SP-A (p < 0.05), lecithin (p < 0.005), and lecithin-sphingomyelin ratio (p < 0.05). A positive correlation was also recorded between amniotic and maternal cortisol (p < 0.008). Considering that all puppies were born alive and mature, these data could provide a potential range of expected amniotic values in full-term new-born dogs. Furthermore, since gestational age was positively correlated with both maternal and amniotic cortisol (p < 0.0001) and amniotic PTX3 (p < 0.05), amniotic fluid seems to be an attractive, innovative, and minimally invasive matrix with potential diagnostic and prognostic utility for the investigation of canine maturity.
评估犬类新生儿成熟度的新可靠标志物的定义在犬科临床实践中至关重要。由于担心对怀孕犬进行羊膜采样的安全性，因此禁止出于诊断目的采集羊水。此外，直到最近的研究报告称，即使在犬科动物中，羊膜穿刺术也是一种可靠且安全的程序，人们才开始将羊水视为废物。在我们的研究中，从 10 只在足月时接受选择性剖宫产的犬的出生时采集的羊水（n=63）被分析，以发现犬类新生儿成熟度的新潜在指标。根据胎龄，将母亲和幼犬分为两组：早期组（从黄体生成素（LH）激增后≤65 天，n=5）和晚期组（从 LH 激增后>65 天，n=5）。还比较了个体/每窝中最轻和最重幼犬的羊水参数，这些幼犬的出生体重差异至少为同窝仔犬的 20%。特别是，研究了羊水中的卵磷脂、神经鞘磷脂、表面活性剂蛋白 A（SP-A）、皮质醇和五聚素 3（PTX3）等物质的含量，这些物质被认为可以预测人类胎儿的发育情况。同时还测量了母体血清中的 SP-A 和皮质醇。犬类羊水可检测到所有的羊水参数。有趣的是，不同羊水参数之间存在相关性。卵磷脂与神经鞘磷脂呈正相关（p<0.0001），与母体 SP-A（p<0.0005）和羊水与母体皮质醇的比值（p<0.004）呈正相关。羊水中的 SP-A 与母体 SP-A（p<0.05）、卵磷脂（p<0.005）和卵磷脂-神经鞘磷脂比值（p<0.05）呈负相关。羊水和母体皮质醇之间也存在正相关（p<0.008）。鉴于所有幼犬均存活且成熟，这些数据可为足月新生犬提供潜在的羊水值范围。此外，由于胎龄与母体和羊水皮质醇（p<0.0001）和羊水 PTX3（p<0.05）呈正相关，羊水似乎是一种有吸引力的、创新的、微创基质，具有用于研究犬类成熟度的潜在诊断和预后价值。
