Related Experiment Videos
Reproductive performance of multiparous rabbit lactating does: effect of lighting programs and PMSG use
1Department of Animal Pathology, Faculty of Veterinary Medicine, University of Santiago de Compostela, Lugo, Spain. laquiari@correo.lugo.usc.es
Reproduction, Nutrition, Development
|October 11, 2001
Summary
Replacing Pregnant Mare Serum Gonadotrophin (PMSG) with specific lighting schedules in does showed mixed results. While 12-h light/12-h dark improved estrus synchronization without PMSG, overall productivity was best when PMSG was used.
Area of Science:
- Animal Science
- Reproductive Biology
- Photoperiodism
Background:
- Oestrous synchronization in multiparous lactating does is crucial for efficient breeding.
- Pregnant Mare Serum Gonadotrophin (PMSG) is commonly used for this purpose.
- Alternative methods, such as controlled lighting schedules, are being explored to replace hormonal treatments.
Purpose of the Study:
- To evaluate if specific lighting schedules can replace PMSG for oestrous synchronization in lactating does.
- To assess the impact of different photoperiods on reproductive performance without PMSG.
- To compare the efficacy of two lighting programs (12-h L/12-h D vs. 8-h L/16-h D) with and without PMSG.
Main Methods:
- Two groups of 20 does were subjected to either a 12-h L/12-h D or an 8-h L/16-h D lighting schedule until 6 days before artificial insemination (AI).
- Photoperiod was then shifted to 16-h L/8-h D until AI, followed by a reduction to initial schedules.
- PMSG was administered in alternating AI cycles (1st, 3rd, 5th), while others received no hormonal treatment.
- Oestrous synchronization was assessed by vulva color; reproductive performance included fertility, prolificity, mortality, litter weight, and weaning rates.
Main Results:
- Oestrous synchronization was superior when PMSG was used with either lighting program.
- Without PMSG, the 12-h L/12-h D schedule resulted in better sexual receptivity than the 8-h L/16-h D schedule.
- Fertility, prolificity, and litter performance at 21 days were not significantly affected by lighting programs or PMSG.
- Mortality at birth was higher under the 12-h L/12-h D program.
- Global productivity was better with PMSG, but the reduction without PMSG was minimal for the 12-h L/12-h D schedule, whereas it was considerable for the 8-h L/16-h D schedule.
Conclusions:
- PMSG improves oestrous synchronization and global productivity in lactating does, regardless of the lighting schedule.
- The 12-h L/12-h D lighting program offers a viable alternative to PMSG for oestrous synchronization with minimal impact on global productivity.
- The 8-h L/16-h D lighting program is less effective for oestrous synchronization and significantly reduces productivity when PMSG is omitted.