Redden Reid R, Neville Tammi L, Black Danielle N, Crosswhite Mellissa R, Dahlen Crosswhite Carl R
Center for Nutrition and Pregnancy and Department of Animal Sciences, North Dakota State University, Fargo, USA.
Texas A&M AgriLife Research & Extension Center and Department of Animal Science, Texas A&M University, San Angelo, TX, USA.
Transl Anim Sci. 2023 Jul 19;7(1):txad081. doi: 10.1093/tas/txad081. eCollection 2023 Jan.
Objectives of this study were to determine effects of exogenous progesterone (via controlled internal drug releasing devices; CIDR) in combination with exogenous gonadotropins (PMSG/hCG) use either at CIDR removal or 1 d before CIDR removal to induce estrus and cyclicity and subsequently enhance the proportion of ewes lambing, lambing rate, prolificacy, and days to lambing in ewes bred out of season. Multiparous ewes ( = 414) were randomly assigned to one of four treatments: untreated (, = 122), 7 d CIDR (, = 97), 7 d CIDR plus P.G. 600 (240 IU pregnant mare serum gonadotropin [PMSG] and 120 IU human chorionic gonadotropin [hCG]) at CIDR removal (, = 97), and 7 d CIDR plus P.G. 600 (240 IU PMSG and 120 IU hCG) 1 d before CIDR removal (, = 98). Rams ( = 15) were joined with ewes immediately after CIDR removal and remained with ewes for a 21 d breeding period. Lambing data were summarized for the first 10 days of the lambing season and overall. Categorical data were analyzed using the GLIMMIX procedure of SAS whereas non-categorical data were analyzed using the mixed procedure. Proportion of ewes lambing in the first 10 d was greater ( < 0.05) for CPG0 and CPG-1 ewes compared with C ewes, which was greater ( < 0.0001) compared with U ewes. Overall proportion of ewes lambing was greater ( ≤ 0.0001) in all treatments utilizing CIDR compared with U ewes, but no differences ( ≥ 0.84) due to P.G. 600 were detected compared with C. Lambing rate in the first 10 d was greater ( < 0.05) for CPG-1 than C, with CPGO being intermediate, and all CIDR-treated ewes being greater than U ( < 0.0001). Overall lambing rate increased ( ≤ 0.0001) in all treatments utilizing CIDR compared with U ewes, but no differences ( ≥ 0.76) due to P.G. 600 were detected compared with C. Prolificacy was similar among all treatments both for the first 10 d of the lambing season ( = 0.86) and overall ( = 0.80). Day of lambing in the lambing season was reduced ( ≤ 0.03) for CPG0 and CPG-1 compared with CIDR-treated ewes, which was reduced ( < 0.0001) compared with U ewes (days 10.6, 9.0, 13.4, and 24.4 ± 0.9 for CPG0, CPG-1, CON, and U, respectively). Though timing of P.G. 600 did not influence results, the combination of CIDR and P.G. 600 enhanced the proportion of lambs born earlier in the lambing season, and incorporating a CIDR with or without P.G. 600 enhanced the overall proportion of ewes lambing and lambing rate in out-of-season breeding scenarios.
本研究的目的是确定外源性孕酮（通过控制内部药物释放装置；CIDR）与外源性促性腺激素（孕马血清促性腺激素/人绒毛膜促性腺激素）联合使用，在去除CIDR时或去除CIDR前1天使用，以诱导发情和周期性，随后提高季节性繁殖母羊的产羔比例、产羔率、多产性和产羔天数。经产母羊（n = 414）被随机分配到四种处理之一：未处理（n = 122）、7天CIDR（n = 97）、在去除CIDR时使用7天CIDR加P.G. 600（240国际单位孕马血清促性腺激素[PMSG]和120国际单位人绒毛膜促性腺激素[hCG]）（n = 97），以及在去除CIDR前1天使用7天CIDR加P.G. 600（240国际单位PMSG和120国际单位hCG）（n = 98）。去除CIDR后立即将公羊（n = 15）与母羊合群，并在21天的繁殖期内一直与母羊在一起。汇总了产羔季节前10天和整个产羔季节的产羔数据。分类数据使用SAS的GLIMMIX程序进行分析，而非分类数据使用混合程序进行分析。与未处理母羊相比，在产羔前10天，CPG0和CPG - 1组母羊的产羔比例更高（P < 0.05），与未处理母羊相比差异极显著（P < 0.0001）。与未处理母羊相比，所有使用CIDR的处理中，母羊的总产羔比例更高（P ≤ 0.0001），但与仅使用CIDR的组相比，P.G. 600处理组未检测到差异（P ≥ 0.84）。在产羔前10天，CPG - 1组的产羔率高于仅使用CIDR的组（P < 0.05），CPG0组居中，所有使用CIDR处理的母羊产羔率均高于未处理母羊（P < 0.0001）。与未处理母羊相比，所有使用CIDR的处理中，总产羔率均有所提高（P ≤ 0.0001），但与仅使用CIDR的组相比，P.G. 600处理组未检测到差异（P ≥ 0.76）。在产羔季节的前10天（P = 0.86）和整个产羔季节（P = 0.80），所有处理的多产性相似。与仅使用CIDR的母羊相比，CPG0和CPG - 1组产羔季节的产羔日期提前（P ≤ 0.03），与未处理母羊相比提前极显著（P < 0.0001）（CPG0、CPG - 1、仅使用CIDR和未处理组的产羔日期分别为10.6、9.0、13.4和24.4 ± 0.9天）。虽然P.G. 600的使用时间不影响结果，但CIDR与P.G. 600的联合使用提高了产羔季节早期出生羔羊的比例，并且在季节性繁殖情况下，无论是否使用P.G. 600，使用CIDR都提高了母羊的总产羔比例和产羔率。
