Embryo production and gene expression in superovulated goats supplemented with de-oiled castor cake before and after detoxification treatment

The use of alternative protein sources that do not impair animal performance is a feasible option to reduce costs associated with animal supplementation. Previous studies indicate that castor cake has a high protein value and good ruminal degradability, making it an attractive alternative dietary source for ruminants. Thus, the aim of this study was to evaluate the effects from ingestion of castor cake (treatment CC) or detoxified castor cake (treatment DCC) on serum IgG levels, in vivo production of goat embryos, and the expression profile of genes related to embryonic development, metabolism, and oxidative stress. The results showed the presence of IgG against ricin only in animals of the CC group. The ovulation rate and the production of transferable embryos in animals of the CC group were lower (P < 0.05) than in the animals fed without castor cake (WCC), but neither group differed significantly from the DCC group. There was no effect of type of diet on the expression of the IGF-IR, IGF-II, and GLUT-1 genes in goat embryos produced in vivo. However, the relative expression of mRNA for the HSP 70.1 gene was significantly higher (P < 0.05) in the CC group than in the WCC group, but did not differ from that of the DCC group. In conclusion, this study showed that supplementation with detoxified castor cake can be used for goat feeding, but caution is necessary when providing castor bean meal in the feed of superovulated breeding females, because ricin in the diet, even at low concentrations, altered IgG levels and the expression of mRNA for HSP 70.1, effects that were accompanied by a lower rate of transferable embryos.

Embryo production in superovulated goats treated with insulin before or after mating or by continuous propylene glycol supplementation

Seventeen adult and cyclic Moxoto goats were synchronized using 60 mg MPA vaginal sponge for 11 days and 50 mug cloprostenol, 48 h before sponge removal, and superovulated with 120 mg pFSH i.m. in decreasing doses at 12 h intervals for three consecutive days. In seven goats, 0.2 IU/kg BW/day of long acting insulin was subcutaneously injected at same time as pFSH, and in the other five goats, the same dose of insulin was injected for three consecutive days starting 24 h after mating. Finally, five goats were supplemented with an oral dose of 80 ml/goat/day of propylene glycol continuously during the experiment. The animals were flushed at 7 days after mating and the embryos were classified based on International Embryo Transfer Society criteria. Blood samples were collected every 3 days for insulin assay. Administration of insulin raised the insulin levels of the goats (p < 0.05), whereas in the group treated with propylene glycol, insulin rate was different only between FSH treatment and after mating (p < 0.05). Similar rates of recovery for total (80.05 +/- 9.78%) or transferable structures (61.03 +/- 15.13%) were obtained. Treatment was not influenced (p > 0.05) by responsiveness to superovulation, which averaged 64%. By contrast, insulin treatments were shown to increase the number of embryos considered excellent with respect to goats supplemented with propylene glycol (p < 0.05). When insulin was given before mating, a strong relationship (r = 0. 90) (p < 0.05) between number of transferable embryo and ovulations was observed in the animals. In conclusion, superovulated goats treated with low doses of exogenous insulin resulted in an enhancement in embryo quality, which was related to changes in circulating insulin concentrations.

Birth of normal kids after microinjection of pronuclear embryos in a transgenic goat (Capra hircus) production program in Brazil

This pilot project was designed to determine if normal kids could be produced after microinjection in pronuclear embryos and subsequent transfer to recipients in a transgenic goat program in Brazil. Twelve donors of the Saanen breed and 17 recipients of an undefined breed were used. The estrus of both donors and recipients was synchronized by a standard progestagen treatment and superovulation obtained by six pFSH injections. Donors in estrus were mated with fertile Saanen bucks. Zygotes were recovered surgically by flushing oviducts. The recovered zygotes with visible pronuclei were microinjected with 500 to 1000 copies of the human G-CSF gene. Two or four embryos were surgically transferred into the oviducts of recipients. One recipient became pregnant and two kids were born. No transgenic goat was identified after PCR analysis. Even though transgenic goats were not obtained, this experiment establishes the basis of a synchronization and superovulation regimen for use in goats raised in Brazil, for the purpose of collecting and manipulating the pronuclear embryos. This project also showed that microinjected one-cell goat embryos can survive to produce live young following surgical transfer.