Akkhaphan Tip-Apa, Taechamaeteekul Preechaphon, Grahofer Alexander, Tummaruk Padet
Center of Excellence in Swine Reproduction, Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Clinic for Swine, Department for Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
Porcine Health Manag. 2025 Jun 11;11(1):33. doi: 10.1186/s40813-025-00448-3.
Prolonged farrowing duration is currently one of the challenges in the swine industry, which leads to postpartum complications by increasing uterine inflammation, and interference with physiological processes after parturition. The aim of the present study was to assess the relationship between uterine involution and uterine vessel size with farrowing duration in temporarily confined sows (during the day of farrowing and for the following 3 days) under tropical climates.
Fourteen Landrace × Yorkshire sows were included in the study. Uterine diameter and uterine vessel size were measured from 2 to 15 days postpartum using B-mode ultrasonography, a non-invasive technique that enables continuous monitoring of uterine involution and detection of reproductive problems in the same sows throughout the 15-day postpartum period. To determine the relationship between farrowing duration and uterine diameter, sows were categorized into two groups: sows with a farrowing duration of ≤ 300 min (normal) and sows with a farrowing duration > 300 min (prolonged). The mean farrowing duration was 200 ± 128 min, with 28.6% of sows experiencing prolonged farrowing. In the prolonged farrowing group, the diameter decreased from 43.5 ± 9.4 mm to 12.4 ± 0.5 mm, while in the normal group, it decreased from 30.7 ± 1.4 mm to 13.6 ± 0.4 mm. On day 2, sows in the prolonged farrowing group exhibited a higher uterine diameter than the normal group (P = 0.042). There was no significant difference in the size of the uterine blood vessels between the two groups (prolonged farrowing: 7.3 ± 1.3 mm to 2.5 ± 0.1 mm; normal farrowing 6.1 ± 0.7 mm to 2.7 ± 0.1 mm) (P = 0.397). However, the uterine diameter was correlated with the size of the uterine blood vessels in sows with either a normal farrowing duration (r = 0.705, P < 0.001) or a prolonged farrowing duration (r = 0.749, P < 0.001).
This is the first study to evaluate and provide initial data on uterine vessel size and its correlation with the uterine diameter in postpartum sows. Although no significant differences between uterine vessel size and farrowing duration were detected, a notable increase in uterine size during the initial 2 days postpartum in temporarily confined sows under tropical climates with prolonged farrowing duration was identified.
产程延长是当前养猪业面临的挑战之一，它会通过增加子宫炎症以及干扰产后生理过程而导致产后并发症。本研究的目的是评估热带气候下临时圈养母猪（分娩当天及随后3天）子宫复旧和子宫血管大小与产程之间的关系。
本研究纳入了14头长白×大白母猪。在产后2至15天使用B超超声测量子宫直径和子宫血管大小，这是一种非侵入性技术，能够在整个产后15天期间持续监测同一母猪的子宫复旧情况并检测生殖问题。为了确定产程与子宫直径之间的关系，将母猪分为两组：产程≤300分钟的母猪（正常）和产程>300分钟的母猪（延长）。平均产程为200±128分钟，28.6%的母猪产程延长。在产程延长组中，子宫直径从43.5±9.4毫米降至12.4±0.5毫米，而在正常组中，子宫直径从30.7±1.4毫米降至13.6±0.4毫米。在产后第2天，产程延长组母猪的子宫直径高于正常组（P = 0.042）。两组之间子宫血管大小无显著差异（产程延长组：7.3±1.3毫米至2.5±0.1毫米；正常产程组6.1±0.7毫米至2.7±0.1毫米）（P = 0.397）。然而，无论产程正常（r = 0.705，P < 0.001）还是产程延长（r = 0.749，P < 0.001），母猪的子宫直径与子宫血管大小均呈正相关。
这是第一项评估产后母猪子宫血管大小及其与子宫直径相关性并提供初步数据的研究。虽然未检测到子宫血管大小与产程之间存在显著差异，但发现在热带气候下临时圈养且产程延长的母猪产后最初2天子宫大小显著增加。
