Publications by authors named "Robb W Bender"

Article Synopsis
  • The study involved 17 nonlactating Holstein cows to assess how increased levels of propylene glycol (PROP) and luteinizing hormone (LH) influence ovarian function and embryo quality during follicle development.
  • PROP administration raised glucose and insulin levels but did not significantly increase the number of large follicles that ovulated, though it did reduce the fertilization rate.
  • The results suggest that an acute rise in insulin before ovulation negatively affects the ovulation rate of large follicles, especially when paired with high LH levels, without impacting embryo quality.
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Our objective was to compare several experimental preparations of a single injection of long-acting recombinant bovine FSH (rbFSH; types A and B) to a porcine pituitary-derived FSH (Folltropin) to superovulate Holstein dairy heifers. Nonlactating, nonpregnant virgin Holstein heifers (n = 56) aged 12 to 15 months were randomly assigned to one of four superstimulatory treatments. Beginning at a random stage of the estrous cycle, all follicles greater than 5 mm were aspirated.

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This manuscript reviews the effect of progesterone (P4) during timed AI protocols in lactating dairy cows. Circulating P4 is determined by a balance between P4 production, primarily by the corpus luteum (CL), and P4 metabolism, primarily by the liver. In dairy cattle, the volume of luteal tissue is a primary determinant of P4 production; however, inadequate circulating P4 is generally due to high P4 metabolism resulting from extremely elevated liver blood flow.

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Natural luteolysis involves multiple pulses of prostaglandin F2alpha (PGF) released by the nonpregnant uterus. This study investigated expression of 18 genes from five distinct pathways, following multiple low-dose pulses of PGF. Cows on Day 9 of the estrous cycle received four intrauterine infusions of 0.

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