Department of Animal Science, North Carolina State University, Raleigh, NC.
Department of Animal Science, North Carolina State University, Raleigh, NC.
Domest Anim Endocrinol. 2019 Apr;67:54-62. doi: 10.1016/j.domaniend.2018.11.002. Epub 2018 Nov 30.
The efficacy of several protocols for ovulation synchronization and timed artificial insemination (TAI) in goats was examined. In addition, the relationship between levels of pregnancy specific protein B (PSPB) during gestation assessed with a commercially available ELISA and the number of offspring at birth was determined. In Experiment 1, 70 does were randomized into four treatments: (1) breed by estrus [BBE], (2) 6-d treatment with a new [C6N], (3) once-used [C61], or (4) twice-used Controled Internal Drug Release (CIDR) device [C62)]. BBE does received two 15 mg doses of prostaglandin-F2α (PGF) at a 10-d interval and were bred 12 h after estrus onset. CIDR groups received a CIDR for 6 d with 15 mg PGF given at CIDR removal. TAI was performed 48 h after CIDR removal and does were given 50 μg GnRH. All does were inseminated with a single dose of frozen semen using a non-surgical, transcervical technique. Pregnancy rates for the BBE, C6N, C61 and C62 treatment groups were 39% ± 12%, 64% ± 12%, 77% ± 12% and 57% ± 12%, respectively, and did not differ. Reuse of CIDRs, even with reuse extending for a total of 21 d, was as effective as new CIDRs for synchronization of ovulation. In Experiment 2, 68 does were randomized into four treatments: (1) BBE, (2) C6N, (3) NC.Synch [NCS], (4) modified NCS [NCSM]. The BBE and C6N groups were as described for Experiment 1. The NCS and NCSM groups received 15 mg PGF on Day 1, 50 μg GnRH on Day 8 and 15 mg PGF on Day 15 (NCS) or Day 15.5 (NCSM). Does were bred by TAI at 72 h (NCS) or 60 h (NCSM) after the second PGF injection. All does in the NCS and NCSM groups received 50 μg GnRH at TAI. Pregnancy rates were 53% ± 12%, 30% ± 11%, 50% ± 11% and 41% ± 12% for does in the BBE, C6N, NCS and NCSM group, respectively, and did not differ. In Experiment 3, 62 does pregnant to TAI were bled at Days 48 and 85 post-insemination for PSPB. Data on kid numbers and birth weights were subsequently recorded. At Day 48 of gestation, PSPB levels for does birthing singletons were lower than for does birthing twins or triplets (25.0 ± 0.1, 28.8 ± 0.1 and 30.7 ± 0 ng/mL, respectively, P<0.05). At Day 85 of gestation, PSPB levels were progressively greater for does birthing singletons versus twins versus triplets (27.0 ± 0.1, 28.5 ± 0.1 and 31.6 ± 0 ng/mL, P<0.05). In conclusion, PSPB concentrations detected using a commercially available ELISA at Day 48 or 85 of gestation could distinguish does carrying single versus multiple fetuses.
本研究旨在检验几种排卵同步和定时人工授精（TAI）方案在山羊中的效果，并确定在妊娠期间使用商业上可用的 ELISA 检测到的妊娠特异性蛋白 B（PSPB）水平与出生时的后代数量之间的关系。在实验 1 中，将 70 只母羊随机分为四组处理：（1）发情期配种[BBE]，（2）新[C6N]的 6 天处理，（3）一次性使用[C61]，或（4）二次使用的控释内部药物释放（CIDR）装置[C62]）。BBE 母羊在 10 天的间隔内接受两次 15mg 剂量的前列腺素 F2α（PGF），并在发情开始后 12 小时配种。CIDR 组接受 6 天的 CIDR 处理，在 CIDR 去除时给予 15mg PGF。TAI 在 CIDR 去除后 48 小时进行，母羊给予 50μg GnRH。所有母羊均采用非手术经宫颈技术用冷冻精液进行单次授精。BBE、C6N、C61 和 C62 处理组的妊娠率分别为 39%±12%、64%±12%、77%±12%和 57%±12%，差异不显著。CIDR 的重复使用，即使重复使用总时长达到 21 天，对于排卵同步化与新 CIDR 一样有效。在实验 2 中，将 68 只母羊随机分为四组处理：（1）BBE，（2）C6N，（3）NC.Synch[NCS]，（4）改良 NCS[NCSM]。BBE 和 C6N 组的处理方式与实验 1 相同。NCS 和 NCSM 组在第 1 天、第 8 天和第 15 天（NCS）或第 15.5 天（NCSM）分别给予 15mg PGF 和 50μg GnRH。在第二次 PGF 注射后 72 小时（NCS）或 60 小时（NCSM）进行 TAI 配种。NCS 和 NCSM 组的所有母羊在 TAI 时给予 50μg GnRH。BBE、C6N、NCS 和 NCSM 组的妊娠率分别为 53%±12%、30%±11%、50%±11%和 41%±12%，差异不显著。在实验 3 中，在人工授精后第 48 天和第 85 天对妊娠的母羊进行采血，以检测妊娠特异性蛋白 B（PSPB）。随后记录幼仔数量和出生体重的数据。在妊娠第 48 天，产单胎的母羊的 PSPB 水平低于产双胞胎或三胞胎的母羊（25.0±0.1、28.8±0.1 和 30.7±0ng/mL，分别为 P<0.05）。在妊娠第 85 天，产单胎的母羊的 PSPB 水平与产双胞胎和三胞胎的母羊相比逐渐增加（27.0±0.1、28.5±0.1 和 31.6±0ng/mL，分别为 P<0.05）。总之，在妊娠第 48 天或第 85 天使用商业上可用的 ELISA 检测到的 PSPB 浓度可以区分携带单胎或多胎的母羊。
