Relationships among Estrous Behavior, Superovulatory Response and Grade 1 Embryo Sex Ratio in Superovulated Holstein Heifers

Relationships between the number of small follicles prior to superovulatory treatment and superovulatory response in Holstein cows.

In order to determine relationships between the number of small follicles prior to superovulatory treatment and superovulatory response, a total of 55 superovulations were induced in Holstein cows. The ovaries were examined ultrasonographically once 0-1.5 days before the initiation of superovulatory treatment. The number of small follicles 3-6 mm in diameter on both ovaries before superovulator...

Progesterone Production in Superovulated Holstein Heifers and in Crossbred Recipient of Embryo Supplemented with Betacarotene and Tocopherol

Two experiments were conducted to evaluate the effect of the intramuscular injection of betacarotene associated to tocopherol on the plasma concentration progesterone of superovulated Holstein heifers (experiment 1) and in crossbred (Bos taurus x Bos indicus) heifers submitted to fixed-time embryo transfer (FTET, experiment 2). In experiment 1, after estrus synchronization and superovulation an...

Fertilization rate and embryo quality in superovulated Holstein heifers artificially inseminated with X-sorted or unsorted sperm

Although studies have demonstrated reasonable pregnancy rates in single-ovulating heifers inseminated with sexed sperm, it is not yet clear if sexed sperm can be successfully used in superovulated females. Therefore, the objective of this trial was to determine fertilization rate and embryo quality in superovulated heifers inseminated with frozen-thawed Xchromosome bearing sperm at 2 different ...

Superovulation of Beef Heifers with Follicle Stimulating Hormone or Human Menopausal Gonadotropin: Acute Effects on Hormone Secretion

The effects of superovulatory treatment (follicle stimulating hormone [FSH] versus human menopausal gonadotropin [HMG]) and of route of administration (intramuscular versus intravenous) of prostaglandin F2a (PGF2a) on hormonal profiles were determined in 32 Angus x Hereford heifers for breeding and subsequent embryo collection and transfer. Heifers were superstimulated either with FSH (total of...

Superovulation 335 EFFECT OF PATERNAL LINE OF DONOR ON SUPEROVULATORY RESPONSE AND EMBRYO QUALITY IN JAPANESE BLACK HEIFERS