P.M. Schmidt

Superovulation of rabbits with FSH alters in vivo development of vitrified morulae.

Morulae were flushed from the oviducts and uteri of New Zealand White (NZW) rabbits superovulated with either 6 (3 d) or 8 (4 d) injections of FSH and from non-superovulated controls. The percentages of embryos recovered from 4 d (100%, n = 8) donors was significantly higher (P < 0.01) than that of 3 d (76%, n = 16) and control (87%, n = 22) donors. Overall, fertilization rates were significantly lower for the 3 d embryos (P < 0.01). Most (86 to 90%) morulae were morphologically suitable for vitrification in an ethylene glycol-based solution. Following storage in liquid nitrogen, morulae were rapidly thawed and transferred to the uteri of pseudopregnant recipients. The total number of kits born for the 3 d, 4 d, and control groups was 40, 61 and 48, respectively. The percentage of live kits from morulae transferred was significantly lower for the 3 d (20%, n = 201) than either the 4 d (36%, n = 169; P < 0.01) or the control (31%, n = 157; P < 0.05) group. The mean number of kits born/recipient for the 3 d (2.4 +/- 2.9), 4 d (4.7 +/- 3.5), and control (3.0 +/- 2.2) protocols did not differ (P > 0.05). The estimated overall efficiency of producing kits based on normal morulae collected for control and 4 d groups, however, was nearly two-fold that for females given 6 FSH treatments. We conclude that the 4 d FSH superovulation regimen enhances the efficiency of rabbit reproductive biotechnology after embryo cryopreservation. These findings have important implications for rabbit colony management using embryo cryopreservation.

Quality control measures in an embryo research program

Abstract The need to establish quality control measures in handling mammalian embryos has been illustrated by a number of recent studies demonstrating a relationship between “toxic laboratory supplies” and embryo mortality. Routine, coordinated testing of biological preparations (e.g., hormones, media, serum, water) and the maintenance of sanitary practices are critical for routine embryo production, handling and effective use. A quality control program that incorporates the principle that “an ounce of prevention is better than a pound of attempted cure” can reduce or eliminate most of the problems that consume valuable time and resources. In a multidisciplinary research program, a systematic approach to quality control relies on careful organization, accurate records, communication, routine testing/verification and common sense. The purpose of this discussion is to highlight basic quality control guidelines that will generate accurate and reproducible research data.

Feline Breeding Management

A comprehensive understanding of behavioral-gonadal-endocrine interrelationships is a prerequisite for the effective management of any feline breeding program. Some of the topics discussed in this article are seasonality of breeding behavior, problems associated with copulation, suggested mating schemes, and pharmacologic control of reproductive cyclicity.