University of Padova, Department of Animal Medicine, Production and Health, Legnaro, Padova, Italy.
J Feline Med Surg. 2024 Jul;26(7):1098612X241248351. doi: 10.1177/1098612X241248351.
The queen is recognised as an induced ovulator. Ovulation without male contact is generally regarded as spontaneous. The aim of this study was to provide an estimate of the incidence of spontaneous ovulation in a population of intact queens presented to a veterinary care facility for both reproductive and non-reproductive reasons. The secondary objective was to determine the roles of age, breed, body weight, presence of tom cats or other cycling queens, and physical contact with humans on triggering spontaneous ovulation, along with its implications.
Serum samples from post-pubertal intact queens presented between January 2020 and June 2023 to the Veterinary Teaching Hospital of the University of Padova, Italy, were retrieved and assayed for progesterone (P4) levels. Serum P4 above 2.0 ng/ml without a history of male contact was considered as proof of spontaneous ovulation.
In total, 31 serum samples from 29 intact post-pubertal queens were obtained. Of the 31 samples, 14 had a P4 concentration above 2.0 ng/ml and 9/29 (31.0%) queens ovulated spontaneously. The mean age and weight of the nine spontaneously ovulating queens were 4.3 ± 5.7 years and 3.7 ± 0.8 kg, respectively. One queen ovulated spontaneously at her first heat at 6 months of age, which makes it the earliest spontaneous ovulation reported.
As both our findings and previous publications indicate that the incidence of spontaneous ovulation in queens is consistently ⩾30%, cats should not be considered strictly induced ovulators, but as a species in which ovulation can be either spontaneous or induced. Since the risk of progesterone-dependent conditions (cystic endometrial hyperplasia - pyometra complex, feline mammary hypertrophy) is increased in these queens, veterinarians should be aware and advise breeders and clients accordingly.
女王被认为是诱导排卵者。没有雄性接触的排卵通常被认为是自发的。本研究的目的是提供一个关于在一个因生殖和非生殖原因而被兽医护理机构就诊的完整女王群体中自发排卵发生率的估计。次要目的是确定年龄、品种、体重、是否有公猫或其他发情母猫、与人类的身体接触对触发自发排卵的作用，以及其意义。
从 2020 年 1 月至 2023 年 6 月间，在意大利帕多瓦大学兽医教学医院就诊的已过青春期的完整女王的血清样本被检索出来，并进行孕激素（P4）水平检测。血清 P4 水平高于 2.0ng/ml 且没有雄性接触史被认为是自发排卵的证据。
共获得 29 只已过青春期完整女王的 31 个血清样本。在这 31 个样本中，有 14 个样本的 P4 浓度高于 2.0ng/ml，9/29（31.0%）只女王自发排卵。9 只自发排卵女王的平均年龄和体重分别为 4.3±5.7 岁和 3.7±0.8kg。其中一只女王在 6 个月大时第一次发情时就自发排卵，这是报告的最早的自发排卵。
由于我们的发现和以前的出版物都表明，女王自发排卵的发生率始终 ⩾30%，因此猫不应被视为严格的诱导排卵者，而是一种排卵可以是自发的或诱导的物种。由于这些女王患孕激素依赖性疾病（囊性子宫内膜增生-子宫积脓综合征、猫乳腺肥大）的风险增加，兽医应该意识到这一点，并相应地向饲养者和客户提供建议。
