Effect of CIDR-based protocols for timed-AI on the conception rate and ovarian functions of Japanese Black beef cows in the early postpartum period
Effect of CIDR-based protocols for timed-AI on the conception rate and ovarian functions of Japanese Black beef cows in the early postpartum period
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DOI：
10.1016/j.theriogenology.2005.02.008
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发表时间：
2005-09-15
期刊：
影响因子：
2.8
通讯作者：
Kawate, N
中科院分区：
文献类型：
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作者：
Sakase, A;Seo, Y;Kawate, N
我们的目的是比较：（1）Ovsynch和Ovsynch + CIDR方案与使用苯甲酸雌二醇（EB）代替Ovsynch + CIDR的第一个GnRH的方案之间定时人工授精（定时AI）的受胎率（产后早期日本黑肉牛）;（2）这些方案对卵巢类固醇血液浓度的影响。对照组（Ovsynch; n = 35）中的奶牛接受标准Ovsynch方案（第0天GnRH类似物，第7天PGF（2 α）类似物，第9天GnRH类似物），第10天（第二次GnRH处理后约20小时）接受定时AI。Ovsynch + CIDR组中的奶牛（n = 31）接受标准Ovsynch方案加CIDR 7天（从第0天开始）。第三处理组（EB + CIDR + GnRH; n = 41）中的奶牛在第0天接受2 mg EB代替首次GnRH处理，随后接受与Ovsynch + CIDR方案相同的处理。Ovsynch + CIDR组的受孕率（67.7%，P < 0.15）高于Ovsynch组（48.6%），EB + CIDR + GnRH组（73.2%，P < 0.05）和CIDR联合组（两个CIDR治疗组联合）（70.8%，P < 0.05）高于Ovsynch组（48.6%）。与Ovsynch组相比，CIDR联合组第7天血浆孕酮浓度升高（P < 0.01），第14、17和21天血浆孕酮浓度降低（P < 0.001）。第7天，Ovsynch组非妊娠奶牛的血浆雌二醇-17 β浓度高于CIDR合并组非妊娠奶牛和所有合并组（所有处理组合并）妊娠奶牛（P < 0.01）。此外，第9天，Ovsynch和CIDR联合组未妊娠奶牛的雌二醇-17 β浓度低于所有联合组妊娠奶牛（P < 0.05）。总之，这两个协议使用CIDR改善受孕率后，定时AI在产后早期哺乳日本黑肉牛相对于Ovsynch协议。CIDR处理可通过维持升高的血液孕酮浓度直至PGF（2 α）处理，防止在Ovsynch方案处理的非妊娠奶牛中观察到的卵泡过早成熟。(c)2005年爱思唯尔公司All rights reserved.
Our objectives were to compare: (1) conception rates (in early postpartum Japanese Black beef cows) to timed-artificial insemination (timed-AI) among Ovsynch and Ovsynch plus CIDR protocols, and a protocol that used estradiol benzoate (EB) in lieu of the first GnRH of the Ovsynch plus CIDR; and (2) the effects of these protocols on blood concentrations of ovarian steroids. Cows in the control group (Ovsynch; n = 35) underwent a standard Ovsynch protocol (GnRH analogue on Day 0, PGF(2 alpha) analogue on Day 7 and GnRH analogue on Day 9), with timed-AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the Ovsynch + CIDR group (n = 3 1) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Cows in the third treatment group (EB + CIDR + GnRH; n = 41) received 2 mg of EB on Day 0 in lieu of the first GnRH treatment, followed by the same treatment as in the Ovsynch + CIDR protocol. The conception rate tended to be greater in the Ovsynch + CIDR group (67.7%, P < 0.15) and was greater in the EB + CIDR + GnRH (73.2%, P < 0.05) and CIDR-combined (both CIDR-treated groups were combined) groups (70.8%, P < 0.05) than in the Ovsynch group (48.6%). Plasma progesterone concentrations were higher on Day 7(P < 0.01) and lower on Days 14,17 and 21 (P < 0.001) in the CIDR-combined group than in the Ovsynch group. Plasma estradiol-17 beta concentrations were higher on Day 7 in the Ovsynch group of non-pregnant cows than in the CIDR-combined group of non-pregnant cows and in an all-combined group (all treatment groups combined) of pregnant cows (P < 0.01). Furthermore, estradiol-17 beta concentrations were lower on Day 9 in the Ovsynch and CIDR-combined groups of non-pregnant cows than in the all-combined group of pregnant cows (P < 0.05). In conclusion, both protocols using CIDR improved conception rates following timed-AI in early postpartum suckled Japanese Black beef cows relative to the Ovsynch protocol. Treatment with a CIDR may prevent early maturation of follicles observed in non-pregnant cows treated with the Ovsynch protocol, by maintaining elevated blood progesterone concentrations until PGF(2 alpha) treatment. (c) 2005 Elsevier Inc. All rights reserved.