1. Infertility: The rabbit or the male rabbit (buck) may have fertility issues preventing successful mating or fertilization.
2. Litter Resorption: During pregnancy, a rabbit may reabsorb some or all of the developing fetuses. This natural process can occur due to various factors such as stress, poor nutrition, uterine infections, or hormonal imbalances.
3. Pregnancy Complication: Health issues or complications during pregnancy may lead to the loss of some or all fetuses. For example, uterine infections, trauma, or certain medications can affect the viability of the litter.
4. Stillbirth: Sometimes, one or more kits may be stillborn, meaning they are born dead. This can happen for various reasons, including genetic defects, birth complications, or infections.
If you are concerned about your rabbit's litter size or reproductive health, it is essential to consult with a veterinarian who specializes in rabbits for proper evaluation and care.