Widener Caitlin Lark, Graves William M, Alward Kayla J, Bohlen Jillian F
Department of Animal and Dairy Science, University of Georgia, Athens, Georgia.
Reprod Domest Anim. 2019 Nov;54(11):1470-1476. doi: 10.1111/rda.13554. Epub 2019 Sep 20.
The objective of this study was to examine the impact of a bovine respiratory disease complex (BRDC) vaccine with a temperature-sensitive modified live vaccine (MLV) infectious bovine rhinotracheitis (IBR) component on oestrous cycle parameters and the follicular pool. Twenty-four Holstein heifers (12.4 ± 0.5 months) previously calfhood vaccinated with an IBR MLV component were enrolled in two replicates (Spring; n = 10 and Fall; n = 14) and were blocked by pre-vaccination bovine viral diarrhoea (BVD) serum neutralizing (SN) titres. Upon enrolment, heifers were oestrous synchronized with sampling beginning at detected oestrus. At their second heat, heifers were vaccinated with a BRDC calfhood vaccine with a MLV (MLV; n = 12) or killed (K; n = 12) IBR component and sampled for two additional cycles. Serum samples for oestrogen (E2) and progesterone (P4) as well as ultrasound data of ovarian structures were collected every other day. Serum samples for anti-Müllerian hormone (AMH) were collected at oestrus and mid-cycle for each cycle, and serum for titres was collected prior to and following vaccination. Data were analysed with the PROC MIXED and GLM procedures of SAS. There was no difference in pre- or post-vaccination titres between MLV and K heifers (p > .5). Vaccination had no impact on P4 concentrations, P4 area under the curve, luteal tissue area, peak E2 production or oestrous cycle length (p > .05). Cycle number did impact AMH concentration (p < .05). In MLV heifers, AMH concentration was highest in cycle 1 (p < .05) while cycles 2 and 3 did not differ (p > .05). This was also true for the K heifers in the Fall replicate (p < .05). Within cycle 2, AMH concentrations were numerically lower between vaccine types (K = 308.22 ± 33.3 pg/ml, MLV = 181.13 ± 32.9 pg/ml; p > .05). Although no differences were seen in overall cycle parameters, differences in AMH concentrations may indicate a reduction of the follicular pool following vaccination and requires further investigation.
本研究的目的是检验一种含有温度敏感型减毒活疫苗（MLV）传染性牛鼻气管炎（IBR）成分的牛呼吸道疾病综合征（BRDC）疫苗对发情周期参数和卵泡池的影响。24头荷斯坦小母牛（12.4±0.5月龄）此前在犊牛期接种过IBR MLV成分疫苗，被分为两个重复组（春季；n = 10头，秋季；n = 14头），并根据接种疫苗前的牛病毒性腹泻（BVD）血清中和（SN）滴度进行分组。入组时，小母牛进行发情同期化处理，从检测到发情开始采样。在第二次发情时，给小母牛接种含有MLV（MLV组；n = 12头）或灭活（K组；n = 12头）IBR成分的BRDC犊牛期疫苗，并在另外两个周期进行采样。每隔一天采集血清样本检测雌激素（E2）和孕酮（P4），以及卵巢结构的超声数据。在每个周期的发情期和周期中期采集抗苗勒管激素（AMH）的血清样本，在接种疫苗前后采集血清检测抗体滴度。数据采用SAS的PROC MIXED和GLM程序进行分析。MLV组和K组小母牛接种疫苗前或后的抗体滴度没有差异（p＞0.5）。接种疫苗对P4浓度、P4曲线下面积、黄体组织面积、E2峰值产量或发情周期长度没有影响（p＞0.05）。周期数确实会影响AMH浓度（p＜0.05）。在MLV组小母牛中，AMH浓度在第1周期最高（p＜
