Traitement ciblé de l'infertilité post-partum chez la vache laitière

奶牛盈利的头号问题是低生育率，这会导致延误、治疗和过早淘汰。低生育率是多种因素综合作用的结果，但似乎在产后第60天左右达到顶峰，恰好在产后开始授精的时候。对产后情况的分析指出了导致低生育率的潜在因素：子宫不完全复旧、感染、乳房炎和炎症状态，但最可能的可疑因素是高挤奶奶牛造成的能量负平衡、摄入量有限、食物质量不佳等。因此，我们通过使用强大的转录转录方法观察对环境的完全反应来分析卵巢前景。我们首先观察了奶牛产后30-60-90和120天不同时期的同步优势卵泡，并以120天为对照，说明在60天时，一些基因通路在这些卵泡中功能不正常，特别是视黄酸依赖通路。根据BHB(β-羟基丁酸)水平对动物进行代谢分析，发现这些动物表达的两条通路：维生素A和维生素D依赖通路。为了将基因组信息转化为实践，我们设计了一个简单的实验，作为缩小规模的初步干预，以证明更大规模的临床试验是合理的。产后动物将在产后50岁时根据没有明显影响生育能力的疾病进行选择。这些动物将被抽样进行血液中的BHb测量。其中一半的动物(24只)将在第50天和70天接受两次维生素A-D注射，另一半将作为对照(24只)。此外，还将比较开放天数、人工授精和获得怀孕的兽医费用的影响。其目标是在授精的关键期为高BHB奶牛提供简单的个体化治疗。这个概念可能看起来过于简单化了，但卵巢似乎可以感觉到季节背景，如鲜草(维生素A)和春天(维生素D)，作为未来能量供应和促进生育的代谢指标。

The number one problem in dairy cows profitability is low fertility which causes delays, treatments and premature culling. The low fertility is the product of a combination of several factors but seems to peak at around day 60 post-partum exactly at the time where producers are starting to inseminate. The analysis of the post-partum context indicates the potential factors involved in low fertility: incomplete uterine involution, infection, mastitis and inflammation status but the most likely suspect is the negative energy balance caused by high milking cows, limited intake capacity, suboptimal quality of food etc. Therefore, we have analysed the ovarian perspective by looking at the complete response to the environment using the powerful transcriptomic approach. We first looked at the synchronized dominant follicles of cows at different period post-partum 30-60-90 and 120, using 120 days as the control reference and illustrates that at 60 days a few gene pathways are not functioning correctly in these follicles, especially the retinoic acid dependant path.A metabolic analysis of the animals according to BHB (beta hydroxy butyrate) level has identified 2 pathways under expressed in these animals: vitamin A and vitamin D dependant pathways. To translate the genomic information into practice we have design a simple experiment that would serve as a preliminary intervention on a reduced scale to justify a larger clinical trial. Post-partum animals will be selected at 50 post-partum based on the absence of obvious diseases which would impact fertility. The animals will be sampled for blood BHB measurements. Half of the animals (24) will be treated with 2 injections of vitamins A-D at days 50 and 70 and the other half will serve as control (24). In addition, the impact on the number of open days, insemination and veterinary cost to obtain a pregnancy will be compared. The goal is to provide a simple individual treatment to high BHB cows in the critical period for insemination. This concept may seems too simplistic but it seems that the ovary can sense the seasonal context as fresh grass (vit A) and spring (vit D) as metabolic indicator of future energy supply and facilitate fertility.