Hashem Nesrein M, El-Hawy Ahmed S, El-Bassiony Moharram F, El-Hamid Ibrahim S Abd, Gonzalez-Bulnes Antonio, Martinez-Ros Paula
Department of Animal and Fish Production, Agriculture Faculty (El-Shatby), Alexandria University, Alexandria 21545, Egypt.
Animal and Poultry Physiology Department, Desert Research Center (DRC), Cairo 11753, Egypt.
Biology (Basel). 2023 Feb 22;12(3):351. doi: 10.3390/biology12030351.
This study is aimed at determining the reproductive performance of anestrous ewes treated with nanoencapsulated GnRH after a progesterone-based protocol for estrus induction was proposed as a way of replacing eCG. A total of sixty anestrous, multiparous, non-lactating Barki ewes were randomly allocated into three homogenous groups and subjected to a CIDR-based estrus induction protocol. The first group (eCG) received an intramuscular (i.m.) injection of 350 IU of eCG at CIDR removal. The second (LNGnRH) and third (HLNGnR) groups received either 25 µg or 50 µg of encapsulated GnRH nanoparticles by the i.m. route in the form of spherical GnRH-encapsulated chitosan-TPP nanoparticles (which were 490.8 nm and had a 13.6 mV positive charge) 48 h after CIDR removal. Follicular dynamics, estrous behavior, luteal activity, and pregnancy outcomes were evaluated. Three days after CIDR removal, the number of large follicles increased by similar amounts in the LNGnRH and eCG groups and were significantly higher in both groups than in the HNGnRH group. However, no differences were observed in the numbers and diameters of CLs among the experimental groups and, on the other hand, treatment with HNGnRH significantly increased blood serum progesterone levels compared with eCG and LNGnRH. Treatment with HNGnRH increased conception, lambing, and fecundity rates ( < 0.05), with the trend of a higher litter size ( = 0.081) compared with eCG, whereas LNGnRH resulted in intermediate values. In conclusion, a dose of 50 µg of GnRH encapsulated in chitosan-TPP nanoparticles can be used as an alternative to eCG in progesterone-based estrus induction protocols in sheep.
本研究旨在确定在基于孕酮的发情诱导方案被提议作为替代马绒毛膜促性腺激素（eCG）的方法后，用纳米包裹的促性腺激素释放激素（GnRH）处理乏情母羊的繁殖性能。总共60只乏情、经产、非泌乳的巴尔基母羊被随机分为三个同质组，并接受基于阴道海绵栓（CIDR）的发情诱导方案。第一组（eCG组）在取出CIDR时肌肉注射350国际单位的eCG。第二组（LNGnRH组）和第三组（HLNGnR组）在取出CIDR 48小时后，通过肌肉注射途径分别接受25微克或50微克的包裹型GnRH纳米颗粒，其形式为球形的GnRH包裹的壳聚糖-三聚磷酸钠纳米颗粒（直径为490.8纳米，带13.6毫伏的正电荷）。评估卵泡动态、发情行为、黄体活性和妊娠结局。取出CIDR三天后，LNGnRH组和eCG组的大卵泡数量增加量相似，且两组均显著高于HNGnRH组。然而，各实验组之间黄体（CL）的数量和直径没有差异，另一方面，与eCG组和LNGnRH组相比，HNGnRH处理显著提高了血清孕酮水平。HNGnRH处理提高了受胎率、产羔率和繁殖力（P<0.05），与eCG组相比，产仔数有更高的趋势（P=0.081），而LNGnRH组的各项指标处于中间值。总之，在基于孕酮的绵羊发情诱导方案中，50微克壳聚糖-三聚磷酸钠纳米颗粒包裹的GnRH可作为eCG的替代品。
