14, 24, 40 Although the hulls are used as bedding for pet rodents and in laboratory animal facilities in India (where they are called paddy husk), few published articles characterize this product. 14 Despite some industrial uses as biofuel and livestock litter, rice hulls are a relatively low-value side product of the rice industry. Rice hulls are the outer husk of rice that is removed during processing and comprise 20% of the weight of the rice crop. 21 In addition, the mycotoxin zearalenone has been found in commercial corncob and leads to delayed vaginal opening in mice. 22, 39 Corncob contains tetrahydrofurandiols, linoleic acid derivatives with estrogenic properties, which disrupt mating behavior in rats 26 and confound some neuroendocrine studies. 34 However, neither mice nor rats prefer corncob over aspen, 20 and corncob influences outcomes in certain types of research. Corncob bedding is economical and facilitates low intracage ammonia. Several types of mouse bedding are commercially available. Their relatively poor moisture control is a major disadvantage that might preclude their widespread use. This study provides information on the merits of rice hulls as laboratory mouse bedding. The expression of Cyp1a2 was 1.7 times higher in the livers of mice housed on rice hulls than on pine shavings, but other differences were not statistically significant. The relative expression of 3 cytochrome p450 genes was compared among mice housed on rice hulls, corncob, reclaimed wood pulp, or pine shavings. However, ammonia was negligible when cages contained 5 young adult female mice. The results of the absorbency tests coupled with the results of preliminary monitoring of intracage ammonia raised concern about the ability of rice hulls to control ammonia levels sufficiently in cages with high occupancy. Rice hulls had higher odds than did corncob or reclaimed wood pulp of having moisture present at the bedding surface. On a per-volume basis, rice hulls were less absorbent than was corncob bedding. In this pilot study, we compared various aspects of bedding performance of rice hulls and other materials. Rice hulls are an economical material that has not been well characterized as a bedding substrate. Corncob is economical and facilitates low intracage ammonia but has undesirable influences on some endocrine studies. Factors that are considered when selecting laboratory mouse bedding include animal health and comfort, cost, effects on personnel, and bioactive properties.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |