Synchronization of Estrus in Sheep in Different Seasons

[Objectives] The aim was to improve and stabilize the estrus synchronization of local sheep in Xinjiang during the breeding season and non-breeding season. [Methods]The data of estrus rate and estrus concentration time were analyzed by different hormone treatment programs. [Results]eding season,whether PMSC was used did not affect the estrus of sheep when sponge and PG were used（ P 〉 0. 05）. Estrus was concentrated in 36-48 h after sponge plugs were removed,and the estrus rate in this period accounted for 74. 19% of the total. In non-breeding season,the estrus rate in the sponge plug plus PGF treatment was only56. 12%,significantly lower than that（ 90. 43%） in the sponge plug plus PG plus PMSG treatment（ P 〈 0. 01）. The estrus was also concentrated in 36-48 h after sponge plugs were removed. The estrus rate at this stage was 67. 42%,accounting for 82. 8% of the total. In breeding season,the estrus rate in sheep injected with333 IU of PMSG（ 81. 96%） was significantly lower than those of sheep injected with 500（ 90. 25%） and 750 IU（ 95. 3%）（ P 〈 0. 05）. [Conclusions] This study provides a theoretical basis for the production enterprises to save a lot of manpower and material resources.

Application of cattle placental stem cells for treating ovarian follicular cyst

BACKGROUND High humidity and temperature in Taiwan have significant effects on the reproductivity of Holstein cattle,resulting in the occurrence of bovine ovarian follicular cyst(OFC).Because of economic loss from OFC,manual rupture and hormone injection have been advocated for the management of OFC.However,these incomplete treatments increase hormone resistance in cattle.Mesenchymal stem cells(MSCs)derived from placental stem cells(PSCs)demonstrate potential properties for the treatment of several diseases via promoting angiogenesis and immune modulation.AIM To establish the possibility of cattle placental stem cells(CPSCs)as a treatment modality for OFC of cows in Taiwan.METHODS The cows with OFC were divided into three groups:control(BC1 and BC2),hormone(H1 and H2),and CPSC(PS1 and PS2)treatment groups.In the hormone treatment group,the cows were given gonadotrophin-releasing hormone(GnRH)-prostaglandin-GnRH intramuscular injection with or without drainage of follicular fluid.In the CPSC treatment group,CPSCs were isolated from the placenta after labor.With the identification of surface antigen on stem cells,the cows were administered ovarian injection of 1×106 or 6×106 CPSCs with drainage.In all groups,OFC was scanned by ultrasound once a week for a total of seven times.The concentrations of estradiol and progesterone in serum were tested in the same period.The estrus cycle was analyzed by food intake and activity.If estrus was detected,artificial insemination was conducted.Then the cow was monitored by ultrasound for confirmation of pregnancy.RESULTS After 7 d of culture,CPSCs were successfully isolated from placental pieces.CPSCs significantly proliferated every 24 h and had high expression of MSC markers such as cluster of differentiation 44,as determined by flow cytometry.Ultrasound showed lower numbers of OFCs with drainage of follicular fluid.We achieved recovery rates of 0%,50%,50%,75%,75%and 75%in BC1,BC2,H1,H2,PS1,and PS2,respectively.Higher concentrations of progesterone were detected in the CPSC treatment groups.However,both hormone and CPSC treatment groups had no significant difference in the concentration of estradiol.The estrus rate was 0%,100%,25%,75%,75%and 75%in BC1,BC2,H1,H2,PS1,and PS2,respectively.The two fetuses were born in H2 and PS1.In brief,cows with CPSC injection achieved higher recovery,estrus,and inseminated conception rates.CONCLUSION CPSCs have efficacy in treating cows with OFC,and thus,may serve as an alternative treatment for reproductive disorders.

Effect of Different Treatments on Estrous Synchronization in Receptor Cows

[ Objective] To find an efficient and low-consumption estrus synchronization method and thus to provide the basis for embryo transfer. [Method] A total of 120 healthy multiparous yellow cattle were selected as receptor cows for embryo transfer and assigned into three groups ran- domly （ n = 40）. To induce estrous synchronization, the cattle in the group I were injected 4 mg prostaglandin （PG） ; those in the group II were first transplanted with vaginal embolism and then injected with 4 mg PG; and those in the group III were first transplanted with vaginal embolism and then injected with 0.4 mg PG and 2.0 ml follicle-stimulating hormone （FSH）. The rate of estrous synchronization, rate of embryo transfer and rejec- tion rate were compared between different treatments. [Result] The rates of estrous synchronization of the group I, II and III were 0%, 80% and 78%, respectively, and their rates of embryo transfer were 27.5%, 60.0% and 45.0%, respectively. [ Conclusion] Transplantation with vaginal embolism followed by injection with PG and FSH is the optimum method to induce estrus synchronization in yellow cattle.