Helping pigs get their jollies

As a supplement to their facility's existing enrichment program, Huntsberry et al. gave pigs hard plastic 'foraging balls', which they adapted from commercially available “Jolly Balls.” Holes were drilled into the balls and then filled with tasty food items such as jellybeans and unsalted peanuts. Animal caretakers suspended the balls from chains in pig enclosures, and pigs used their snouts to knock treats out of the holes. This enrichment device was a simple and effective way to encourage pigs to show species-typical foraging behavior. See page 411

An innovative feeder alternative

Toler and colleagues tested and validated designs for rodent meal-type feeder assemblies that used disposable plastic cups instead of industry standard glass or stainless steel feeders. Plastic cups were covered with stainless steel shields that gave rats and mice full access to feed but prevented them from chewing on the plastic. The plastic cups could be unstacked, filled and sealed by a machine. The use of disposable cups that are processed automatically can reduce labor associated with filling, emptying and sanitation and can limit employee contact with feed that may contain active pharmaceutical ingredients. See page 415

Rat caging for 'real life' conditions

Though the Guide provides clear recommendations for rodent housing density, logistical constraints may sometimes prevent facilities from giving rodents the 'ideal' amount of space. Bean et al. investigated whether housing Long Evans and Fischer 344 rats from birth through adulthood at higher densities than those recommended in the Guide would affect behavioral or physiological parameters related to stress. After rats reached puberty, the authors rehoused them with unfamiliar cagemates. Overall, housing density had little effect on the parameters measured. See page 421