Meloni Tea, Comin Antonella, Rota Alessandro, Peric Tanja, Contri Alberto, Veronesi Maria Cristina
Department of Health, Animal Science and Food Safety, Faculty of Veterinary Medicine, Università degli Studi di Milano, 20133 Milan, Italy.
Department of Food Science, University of Udine, Udine, Italy.
Theriogenology. 2014 Jun;81(9):1307-11. doi: 10.1016/j.theriogenology.2014.02.013. Epub 2014 Feb 22.
Insulin-like growth factor-I (IGF-I) and non-esterified fatty acids (NEFA) play an essential role in fetal growth and development. To date, fetal fluids IGF-I and NEFA levels at term canine pregnancy are unknown and could be related to the neonatal development and breed size. For these reasons, the aims of the present study were as follows: (1) to evaluate IGF-I and NEFA concentrations in fetal fluids collected from normally developed and viable newborn puppies born at term of normal pregnancies; (2) to assess possible differences between IGF-I and NEFA levels in amniotic compared with allantoic fluid; (3) to detect possible relationship between breed body size and IGF-I and NEFA amniotic and allantoic concentrations; (4) to evaluate possible differences in IGF-I fetal fluids levels between male and female puppies; and (5) to assess possible correlations between the two hormones in each type of fluid. The study enrolled 25 pure breed bitches submitted to elective Cesarean section at term because of the high risk of dystocia or previous troubles at parturition. At surgery, amniotic and allantoic fluids were collected and assayed for IGF-I and NEFA. IGF-I and NEFA amounts in both amniotic and allantoic fluids of different breed size bitches (small: ≤10 kg; medium: 11-25 kg; large: 26-40 kg) were detected, as well as the effect of gender on IGF-I levels. On a total of 73 amniotic and 76 allantoic samples collected by normal, viable, and mature newborns, the mean IGF-I concentration was significantly higher in amniotic than in allantoic fluid in all three groups, but the amniotic IGF-I levels were significantly lower in small and medium size bitches when compared with large ones. No significant differences were found in allantoic IGF-I concentrations among size groups. A significant effect of the puppy gender on IGF-I content in both fetal fluids was not reported. Regarding NEFA, in all the three groups, the mean NEFA concentration did not significantly differ between amnion and allantois, but in both fetal fluids, higher NEFA levels were detected in samples belonging to small breeds when compared with medium and large. These data strongly indicated that, also in the dog, a relation between fetal fluids IGF-I and NEFA concentrations and breed size exists. Further research is needed to elucidate the possible role of IGF-I and NEFA in the pathologic conditions related to canine fetal growth.
胰岛素样生长因子-I（IGF-I）和非酯化脂肪酸（NEFA）在胎儿生长发育中起着至关重要的作用。迄今为止，足月犬妊娠时胎儿体液中IGF-I和NEFA的水平尚不清楚，且可能与新生儿发育及品种大小有关。基于这些原因，本研究的目的如下：（1）评估从正常妊娠足月出生的发育正常且存活的新生幼犬收集的胎儿体液中IGF-I和NEFA的浓度；（2）评估羊水与尿囊液中IGF-I和NEFA水平的可能差异；（3）检测品种体型与羊水和尿囊液中IGF-I及NEFA浓度之间的可能关系；（4）评估雄性和雌性幼犬胎儿体液中IGF-I水平的可能差异；（5）评估每种类型体液中两种激素之间的可能相关性。该研究纳入了25只纯种母犬，由于难产风险高或既往分娩时有问题，在足月时接受了择期剖宫产。手术时，收集羊水和尿囊液并检测其中的IGF-I和NEFA。检测了不同品种体型母犬（小型：≤10千克；中型：11 - 25千克；大型：26 - 40千克）羊水和尿囊液中IGF-I和NEFA的含量，以及性别对IGF-I水平的影响。在正常、存活且成熟的新生儿收集的总共73份羊水和76份尿囊液样本中，三组中羊水中IGF-I的平均浓度均显著高于尿囊液，但与大型母犬相比，小型和中型母犬羊水IGF-I水平显著较低。各体型组尿囊液中IGF-I浓度未发现显著差异。未报告幼犬性别对两种胎儿体液中IGF-I含量有显著影响。关于NEFA，在所有三组中，羊膜和尿囊液中NEFA的平均浓度无显著差异，但在两种胎儿体液中，与中型和大型相比，小型品种样本中检测到的NEFA水平更高。这些数据有力地表明，在犬中，胎儿体液中IGF-I和NEFA浓度与品种大小之间也存在关联。需要进一步研究以阐明IGF-I和NEFA在与犬胎儿生长相关的病理状况中的可能作用。
