Heart block: Failure of the heart's normal rhythm controls leading to arrhythmia. Heart block: Impairment of conduction in heart excitation. It is often applied specifically to atrioventricular heart block. Heart block: recurrent sudden attacks of unconsciousness caused by impaired conduction of the impulse that regulates the heartbeat.
For pet rabbits and show rabbits, pine is completely safe for rabbit litter, especially kiln-dried pine. Kiln-dried pine is also the cheapest rabbit litter on the market. And since it does a comparable job to all the other litters, pine shavings as rabbit litter and rabbit bedding gets our top vote. See Rabbit Bedding for comparisons with several other rabbit bedding materials, and more recommendations.
In answer to the question, Is it safe to sleep with your baby?, under most circumstances, co-sleeping is likely to be very safe and beneficial; but it depends on how it is done. If the parent(s) smoke or take drugs, co-sleeping is risky. Sleeping with an infant on a waterbed, couch, soft bed, or any bed that has gaps or ledges into which the infant can fall, can be risky for the infant. It is more ideal to sleep on a firm mattress, and to limit the use of pillows and blankets.