Praxitelous Anastasia, Katsoulos Panagiotis D, Tsaousioti Angeliki, Brozos Christos, Theodosiadou Ekaterini K, Boscos Constantin M, Tsousis Georgios
Clinic of Farm Animals, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece.
Department of Physiology, Faculty of Veterinary Science, School of Health Sciences, University of Thessaly, 43100 Karditsa, Greece.
Animals (Basel). 2023 May 4;13(9):1537. doi: 10.3390/ani13091537.
The purpose of this study was to assess the ovarian and energy status of multiparous lame dairy cows at the end of puerperium and investigate their responsiveness to estrous synchronization treatment regimens. Initial lameness scoring was performed at 28 ± 5 and 37 ± 5 d post partum, followed by lesion documentation and treatment. Cows were blocked by lameness severity and were randomly allocated to an estrous synchronization treatment regimen with seven days of progesterone supplementation (group LP, = 26) or with an administration of PGF twice, 14 d apart (group LC, = 26). Non-lame cows served as controls (group C, = 27) and the same treatment regimen was imposed as that for group LC. Twelve days after estrous presynchronization, an Ovsynch treatment regimen and timed AI were imposed. Ultrasonography of the ovaries and blood sampling for progesterone were used to assess cyclicity status, whereas β-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA) were used to assess energy status. Lame cows were to a greater proportion non-cycling (36.5% vs. 11.1%; = 0.02), had greater overall NEFA concentrations (0.32 ± 0.02 vs. 0.26 ± 0.02 mEq/L; = 0.02) and a greater incidence of elevated NEFA concentrations (53.9% vs. 29.6%, = 0.04) compared to control cows. However, no interaction between energy and lameness status was evident regarding non-cycling cows. The percentage of cows responding to the presynchronization, synchronization and ovulating did not differ between groups LP, LC, and C. The first-service conception rate (FSCR) tended to be greater for group C (37.0%) compared to group LP (16.0%; = 0.08). Long-term reproductive performance did not differ between lame and control cows, although culling rates did (21.2% vs. 0%, respectivly; = 0.01). The severity of lameness had an effect on culling rates (30.6% vs. 0% for cows with marked vs. moderate lameness; = 0.01), whereas the type of lesion largely explained poor reproductive performance (FSCR 13.9% vs. 40.0% for cows with claw horn disruptions vs. infectious lesions; = 0.04). Conclusively, cows that were lame during puerperium are at a greater risk of not cycling irrespective of energy status. Treatment regimens for the synchronization of ovulation seem to be efficient at resuming ovarian cyclicity. Marked lameness was detrimental to survivability, whereas cows with claw horn lesions had compromised reproductive capacity.
本研究的目的是评估经产跛行奶牛在产褥期末的卵巢和能量状态，并调查它们对发情同步化处理方案的反应。在产后28±5天和37±5天进行初始跛行评分，随后记录病变并进行治疗。奶牛按跛行严重程度进行分组，并随机分配到发情同步化处理方案中，一组补充7天孕酮（LP组，n = 26），另一组间隔14天注射两次PGF（LC组，n = 26）。非跛行奶牛作为对照组（C组，n = 27），采用与LC组相同的处理方案。在发情预同步化12天后，实施Ovsynch处理方案和定时人工授精。通过卵巢超声检查和孕酮血样检测来评估发情周期状态，而β-羟丁酸（BHBA）和非酯化脂肪酸（NEFA）则用于评估能量状态。与对照奶牛相比，跛行奶牛非发情周期的比例更高（36.5%对11.1%；P = 0.02），总体NEFA浓度更高（0.32±0.02对0.26±0.02 mEq/L；P = 0.02），NEFA浓度升高的发生率也更高（53.9%对29.6%，P = 0.04）。然而，在非发情周期奶牛中，能量和跛行状态之间没有明显的相互作用。LP组、LC组和C组奶牛对预同步化、同步化和排卵的反应百分比没有差异。C组的首次输精受胎率（FSCR）倾向于高于LP组（37.0%对16.0%；P = 0.08）。跛行奶牛和对照奶牛的长期繁殖性能没有差异，尽管淘汰率有所不同（分别为21.2%对0%；P = 0.01）。跛行严重程度对淘汰率有影响（明显跛行奶牛与中度跛行奶牛的淘汰率分别为30.6%对0%；P = 0.01），而病变类型在很大程度上解释了繁殖性能不佳的原因（蹄角破坏奶牛与感染性病变奶牛的FSCR分别为13.9%对40.0%；P = 0.04）。总之，产褥期跛行的奶牛无论能量状态如何，不发情的风险都更高。排卵同步化的处理方案似乎能有效地恢复卵巢周期。明显跛行对生存能力有害，而患有蹄角病变的奶牛繁殖能力受损。
