them. Boiled egg whites and small pieces of clean, cooked chicken are also sources of extra protein. They can also eat wheat grain, sunflower seeds, and locusts. The teeth of Campbell's dwarf hamster never stop growing. Like all rodents, they must, therefore, gnaw regularly to keep their incisors from growing into the skin of the mouth and causing pain and irritation. Smooth, young wood from nontoxic trees, such as apple and willow, is readily used by most species in the genus. Most pet stores sell nontoxic wooden chews designed for rodents in captivity. Certain food items commonly consumed by humans are toxic to hamsters and should be avoided completely in captivity. Grapes and raisins may contribute to acute renal failure, due to their high level of acidity. Chocolate and other sticky foods such peanut butter may solidify in a hamster's cheek pouches and lead to infections, which can lead to death. In the wild, the diets of Campbell's dwarf hamsters vary across the population range. A total of 51 different species of plants were identified to be consumed by the Transbaikalia population, the most common being Stipa capillata and species of Allium. However, in Tuva, only 10 species of plant were identified to be consumed by the population, the most common being Potentilla. Campbell's dwarf hamster is a natural predator of burrowing worms and grubs. Breeding In Tuva, the breeding season of Campbell's dwarf hamster begins in April, and in Mongolia, it begins in at the end of April or the beginning of May. However, in all distribution ranges, it ends in late September or early October. In captivity, Campbell's dwarf hamsters breed throughout the year, with no fixed breeding season, but a large number are born in the summer months. In the wild, three to four litters are produced each year, with an average of eight offspring per litter. In captivity, females can have between one and 18 litters per year, with one to nine offspring per litter. In captivity, the gestation period for Campbell's dwarf hamster is between 18 and 20 days, and the shortest gestation period recorded for a captive female was 13 days. The male hamster is likely to assist the female during birth. The male may pull the offspring from the birth canal, clean them, or collect food for the mother and offspring. When the offspring are born, they are hairless and have a body