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Differences in productive robustness in rabbits selected for reproductive longevity or litter size
P Theilgaard1, M Baselga, E Blas
11Instituto de Ciencia y Tecnología Animal, Universidad Politécnica de Valencia, Camino de Vera s/n. 46022 Valencia, Spain.
Animal : an International Journal of Animal Bioscience
|March 27, 2012
Summary
Rabbit does selected for reproductive longevity (LP) better handle productive challenges than those selected for litter size (V). LP rabbits show greater robustness and adaptability during demanding reproductive cycles.
Area of Science:
- Animal Science
- Reproductive Biology
- Animal Genetics
Background:
- Selective breeding impacts animal physiology and performance.
- Understanding trade-offs between reproductive traits is crucial for livestock management.
- Rabbit production systems require efficient reproductive efficiency and maternal care.
Purpose of the Study:
- To compare the productive performance and physiological resilience of a rabbit line selected for reproductive longevity (LP) against a line selected for litter size (V).
- To evaluate how different reproductive challenges (parity, litter size) affect body condition, energy reserves, and milk production in these two rabbit lines.
Main Methods:
- Utilized 133 rabbit does from LP and V lines, subjected to varying reproductive efforts (insemination timing, litter size).
- Monitored reproductive performance, body condition (perirenal fat thickness), estimated body energy, dry matter intake, and milk yield.
- Assessed physiological responses during different lactation stages and parities.
Main Results:
- LP does exhibited higher initial live weight, perirenal fat thickness, and estimated body energy compared to V does.
- During high-demand lactation (nine kits), LP does showed greater milk yield but reduced fat recovery, while V does maintained better body condition.
- Under lower demand (five kits), LP does maintained higher live weight and body condition, indicating better adaptability to varying challenges.
Conclusions:
- The rabbit line selected for reproductive longevity (LP) demonstrates superior robustness in managing productive challenges compared to the line selected for reproductive intensity (V).
- LP rabbits show a more adaptable physiological response to varying reproductive demands, suggesting a broader genetic basis for resilience.
- These findings have implications for breeding strategies aimed at improving overall rabbit productivity and welfare by balancing reproductive traits.
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